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Kanmaz S, Yılmaz S, Olculu CB, Toprak DE, Ince T, Yılmaz Ö, Atas Y, Sen G, Şimşek E, Serin HM, Durmuşalioğlu EA, Işık E, Atik T, Aktan G, Cogulu O, Gokben S, Ozkınay F, Tekgul H. The Utility of Genetic Testing in Infantile Epileptic Spasms Syndrome: A Step-Based Approach in the Next-Generation Sequencing Era. Pediatr Neurol 2024; 157:100-107. [PMID: 38905742 DOI: 10.1016/j.pediatrneurol.2024.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 04/29/2024] [Accepted: 05/27/2024] [Indexed: 06/23/2024]
Abstract
BACKGROUND To evaluate the utility of genetic testing for etiology-specific diagnosis (ESD) in infantile epileptic spasms syndrome (IESS) with a step-based diagnostic approach in the next-generation sequencing (NGS) era. METHODS The study cohort consisted of 314 patients with IESS, followed by the Pediatric Neurology Division of Ege University Hospital between 2005 and 2021. The ESD was evaluated using a step-based approach: step I (clinical phenomenology), step II (neuroimaging), step III (metabolic screening), and step IV (genetic testing). The diagnostic utility of genetic testing was evaluated to compare the early-NGS period (2005 to 2013, n = 183) and the NGS era (2014 to 2021, n = 131). RESULTS An ESD was established in 221 of 314 (70.4%) infants with IESS: structural, 40.8%; genetic, 17.2%; metabolic, 8.3%; immune-infectious, 4.1%. The diagnostic yield of genetic testing increased from 8.9% to 41.7% in the cohort during the four follow-up periods. The rate of unknown etiology decreased from 34.9% to 22.1% during the follow-up periods. The genetic ESD was established as 27.4% with genetic testing in the NGS era. The genetic testing in the NGS era increased dramatically in subgroups with unknown and structural etiologies. The diagnostic yields of the epilepsy panels increased from 7.6% to 19.2%. However, the diagnostic yield of whole exome sequencing remained at similar levels during the early-NGS period at 54.5% and in the NGS era at 59%. CONCLUSIONS The more genetic ESD (27.4%) was defined for IESS in the NGS era with the implication of precision therapy (37.7%).
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Affiliation(s)
- Seda Kanmaz
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Sanem Yılmaz
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye.
| | - Cemile Büşra Olculu
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Dilara Ece Toprak
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Tuğçe Ince
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Özlem Yılmaz
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Yavuz Atas
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Gursel Sen
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Erdem Şimşek
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Hepsen Mine Serin
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Enise Avcı Durmuşalioğlu
- Division of Pediatric Genetics, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Esra Işık
- Division of Pediatric Genetics, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Tahir Atik
- Division of Pediatric Genetics, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Gul Aktan
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Ozgur Cogulu
- Division of Pediatric Genetics, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Sarenur Gokben
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Ferda Ozkınay
- Division of Pediatric Genetics, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
| | - Hasan Tekgul
- Division of Child Neurology, Department of Pediatrics, Ege University Medical Faculty, Izmir, Turkiye
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Kleinendorst L, Abawi O, Vos N, van der Valk ES, Maas SM, Morgan AT, Hildebrand MS, Da Silva JD, Florijn RJ, Lauffer P, Visser JA, van Rossum EFC, van den Akker ELT, van Haelst MM. GNB1 and obesity: Evidence for a correlation between haploinsufficiency and syndromic obesity. Clin Obes 2024; 14:e12661. [PMID: 38596856 DOI: 10.1111/cob.12661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 03/26/2024] [Indexed: 04/11/2024]
Abstract
Most patients with GNB1 encephalopathy have developmental delay and/or intellectual disability, brain anomalies and seizures. Recently, two cases with GNB1 encephalopathy caused by haploinsufficiency have been reported that also show a Prader-Willi-like phenotype of childhood hypotonia and severe obesity. Here we present three new cases from our expert centre for genetic obesity in which GNB1 truncating and splice variants, probably leading to haploinsufficiency, were identified. They all have obesity, hyperphagia and intellectual deficit. The clinical cases and their weight courses are presented, together with a review of all 68 published cases with GNB1 encephalopathy. Information on weight was not mentioned in most of these articles, so we contacted authors for additional clinical information on weight status and hyperphagia. Of the 42 patients whose weight status we could determine, obesity was present in 8 patients (19%). Obesity is significantly over-represented in the group with truncating and splicing variants. In this group, we see an obesity prevalence of 75%. Since GNB1 has been linked to several key genes in the hypothalamic leptin-melanocortin pathway, which regulates satiety and energy expenditure, our data support the potential association between GNB1 haploinsufficiency and genetic obesity. We also suggest GNB1 is a candidate gene for the known obesity phenotype of the 1p36 microdeletion syndrome given this chromosomal region includes the GNB1 gene. Knowledge of an additional obesity phenotype is important for prognosis, early interventions against obesity and awareness when prescribing weight-inducing medication.
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Affiliation(s)
- Lotte Kleinendorst
- Department of Human Genetics, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
- Emma Center for Personalized Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Ozair Abawi
- Department of Pediatrics, Division of Endocrinology, Erasmus MC-Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, the Netherlands
- Obesity Center CGG, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Niels Vos
- Department of Human Genetics, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Eline S van der Valk
- Obesity Center CGG, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Saskia M Maas
- Department of Human Genetics, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Michael S Hildebrand
- Murdoch Children's Research Institute, Melbourne, Australia
- Department of Medicine, Austin Health, University of Melbourne, Melbourne, Australia
| | - Jorge D Da Silva
- Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar Universitário do Porto & Unit for Multidisciplinary Research in Biomedicine, Abel Salazar Biomedical Sciences Institute, Porto University, Porto, Portugal
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Ralph J Florijn
- Department of Human Genetics, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Peter Lauffer
- Department of Human Genetics, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Jenny A Visser
- Obesity Center CGG, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Elisabeth F C van Rossum
- Obesity Center CGG, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
- Department of Internal Medicine, Division of Endocrinology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Erica L T van den Akker
- Department of Pediatrics, Division of Endocrinology, Erasmus MC-Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, the Netherlands
- Obesity Center CGG, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Mieke M van Haelst
- Department of Human Genetics, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
- Emma Center for Personalized Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
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3
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Cheng M, Bai L, Yang Y, Liu W, Niu X, Chen Y, Tan Q, Yang X, Wu Q, Zhao HQ, Zhang Y. Novel copy number variations and phenotypes of infantile epileptic spasms syndrome. Clin Genet 2024; 106:161-179. [PMID: 38544467 DOI: 10.1111/cge.14520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 07/02/2024]
Abstract
We summarize the copy number variations (CNVs) and phenotype spectrum of infantile epileptic spasms syndrome (IESS) in a Chinese cohort. The CNVs were identified by genomic copy number variation sequencing. The CNVs and clinical data were analyzed. 74 IESS children with CNVs were enrolled. 35 kinds of CNVs were identified. There were 11 deletions and 5 duplications not reported previously in IESS, including 2 CNVs not reported in epilepsy. 87.8% were de novo, 9.5% were inherited from mother and 2.7% from father. Mosaicism occurred in one patient with Xq21.31q25 duplication. 16.2% (12/74) were 1p36 deletion, and 20.3% (15/74) were 15q11-q13 duplication. The age of seizure onset ranged from 17 days to 24 months. Seizure types included epileptic spasms, focal seizures, tonic seizures, and myoclonic seizures. All patients displayed developmental delay. Additional features included craniofacial anomaly, microcephaly, congenital heart defects, and hemangioma. 29.7% of patients were seizure-free for more than 12 months, and 70.3% still had seizures after trying 2 or more anti-seizure medications. In conclusion, CNVs is a prominent etiology of IESS. 1p36 deletion and 15q duplication occurred most frequently. CNV detection should be performed in patients with IESS of unknown causes, especially in children with craniofacial anomalies and microcephaly.
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Affiliation(s)
- Miaomiao Cheng
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Ling Bai
- Research and Development Center, Beijing USCI Medical Laboratory Co., Ltd, Beijing, China
| | - Ying Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Wenwei Liu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xueyang Niu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yi Chen
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Quanzhen Tan
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xiaoling Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Qixi Wu
- Research and Development Center, Beijing USCI Medical Laboratory Co., Ltd, Beijing, China
| | - Han-Qing Zhao
- Research and Development Center, Beijing USCI Medical Laboratory Co., Ltd, Beijing, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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4
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He H, Cao X, He F, Zhang W, Wang X, Peng P, Xie C, Yin F, Li D, Li J, Wang M, Klüssendorf M, Jentsch TJ, Stauber T, Peng J. Mutations in CLCN6 as a Novel Genetic Cause of Neuronal Ceroid Lipofuscinosis. Ann Neurol 2024. [PMID: 38877824 DOI: 10.1002/ana.27002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 06/16/2024]
Abstract
OBJECTIVE The aim of this study was to explore the pathogenesis of CLCN6-related disease and to assess whether its Cl-/H+-exchange activity is crucial for the biological role of ClC-6. METHODS We performed whole-exome sequencing on a girl with development delay, intractable epilepsy, behavioral abnormities, retinal dysfunction, progressive brain atrophy, suggestive of neuronal ceroid lipofuscinoses (NCLs). We generated and analyzed the first knock-in mouse model of a patient variant (p.E200A) and compared it with a Clcn6-/- mouse model. Additional functional tests were performed with heterologous expression of mutant ClC-6. RESULTS We identified a de novo heterozygous p.E200A variant in the proband. Expression of disease-causing ClC-6E200A or ClC-6Y553C mutants blocked autophagic flux and activated transcription factors EB (TFEB) and E3 (TFE3), leading to autophagic vesicle and cholesterol accumulation. Such alterations were absent with a transport-deficient ClC-6E267A mutant. Clcn6E200A/+ mice developed severe neurodegeneration with typical features of NCLs. Mutant ClC-6E200A, but not loss of ClC-6 in Clcn6-/- mice, increased lysosomal biogenesis by suppressing mTORC1-TFEB signaling, blocked autophagic flux through impairing lysosomal function, and increased apoptosis. Carbohydrate and lipid deposits accumulated in Clcn6E200A/+ brain, while only lipid storage was found in Clcn6-/- brain. Lysosome dysfunction, autophagy defects, and gliosis were early pathogenic events preceding neuron loss. INTERPRETATION CLCN6 is a novel genetic cause of NCLs, highlighting the importance of considering CLCN6 mutations in the diagnostic workup for molecularly undefined forms of NCLs. Uncoupling of Cl- transport from H+ countertransport in the E200A mutant has a dominant effect on the autophagic/lysosomal pathway. ANN NEUROL 2024.
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Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Xiaoshuang Cao
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Wen Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Xiaole Wang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Pan Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Changning Xie
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Dengfeng Li
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, China
- Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, China
| | - Jiada Li
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, China
- Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, China
| | - Minghui Wang
- The First People's Hospital of Changde, Changde, China
| | - Malte Klüssendorf
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
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Yang Y, Luo H, Pan L, Feng C, Guo Z, Zou Y, Zeng B, Huang S, Yuan H, Wu P, Liu D, Dan Y, Xiao J, Li X, Chen Z, Zeng XN, Jiang X, Yang B, Liu Y, Liu Y. Reevaluating the splice-altering variant in TECTA as a cause of nonsyndromic hearing loss DFNA8/12 by functional analysis of RNA. Hum Mol Genet 2024:ddae071. [PMID: 38676628 DOI: 10.1093/hmg/ddae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/25/2024] [Accepted: 04/19/2024] [Indexed: 04/29/2024] Open
Abstract
PURPOSE The aim of this study was to determine the genetic cause of early onset autosomal dominant hearing loss segregating in five-generation kindred of Chinese descent and provide preimplantation genetic testing (PGT)for them. METHODS Clinical examination, pedigree analysis and exome sequencing were carried out on the family. Minigene-based splicing analysis, in vivo RNA analysis and protein structure prediction by molecular modeling were conducted on the candidate variant. PGT for the causative variation and chromosome aneuploidis based on SNP analysis has been used for avoidance of hearing loss in this family. RESULTS All the affected individuals presented with moderate down-sloping hearing loss and whole-exome sequencing identified a novel splice-site variant c.5383+6T>A in the tested subjects within the TECTA locus. Genotyping of all the 32 family members confirmed segregation of this variant and the hearing loss phenotype in the extended family. Functional analysis of RNA and molecular modeling indicates that c.5383+6T>A is a pathogenic splice-site variant and should be considered as genetic cause of the hearing loss. Furthermore, a successful singleton pregnancy with no variation in TECTA c.5383+6 was established and a healthy male child was born by PGT. CONCLUSION We have identified a novel variant c.5383+6T>A in TECTA ZA-ZP inter-domain, which could be attributable to the early-onset autosomal dominant hearing loss. The implications of our study are valuable in elucidating the disrupted RNA splicing and uncovering the genetic cause of hearing loss with TECTA pathogenic variants, as well as providing reproductive approaches to healthy offspring.
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Affiliation(s)
- Yan Yang
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Haiyan Luo
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Lijuan Pan
- Department of Obstetrics, Xiangya Hospital, Central South University, No. 87, Xiangya Road, Kaifu District, Changsha City, Hunan Province, 410083, China
| | - Chuanxin Feng
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Zhen Guo
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Yongyi Zou
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Baitao Zeng
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Shuhui Huang
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Huizhen Yuan
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Ping Wu
- Department of Otolaryngology, Head and Neck Surgery, The Second Affiliated Hospital of Nanchang University, No. 566, University Avenue Road, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Danping Liu
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Yi Dan
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Junfang Xiao
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - XinYu Li
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - ZhongFa Chen
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Xiao Ni Zeng
- Department of Neurology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zhengjie Road, Donghu District, Nanchang City, Jiangxi Province, 330006, China
| | - XiangLong Jiang
- Nan Chang Reproductive Hospital, No. 198, Jinggangshan Avenue Road, Qingyun Pu District, Nanchang City, Jiangxi Province Nanchang, 330006, China
| | - Bicheng Yang
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
| | - Yuhe Liu
- Department of Otolaryngology, Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, No. 95 Yongan Road, Xicheng District, Beijing, 100050, China
| | - Yanqiu Liu
- Jiangxi Key Laboratory of Birth Defect Prevention and Control, Jiangxi Maternal and Child Health Hospital, No. 508, Xizhan Street, Honggutan District, Nanchang City, Jiangxi Province, 330006, China
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Wang X, Huang Y, Chen L, Mai J, Fang D, Mo T, Qi X, Zeng H. A Potential Mechanism of Neurological Impairment in Children With Infantile Spasm: Based on Microanatomic Structure Analysis Employing Voxel-Based Morphometry and Surface-Based Morphometry. Pediatr Neurol 2024; 153:116-124. [PMID: 38367486 DOI: 10.1016/j.pediatrneurol.2023.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 10/09/2023] [Accepted: 12/11/2023] [Indexed: 02/19/2024]
Abstract
BACKGROUND Infantile epileptic spasms syndrome (IESS) would accompany with severe neurological impairment. Our study aimed to explore the potential mechanism by employing voxel-based and surface-based morphometry to detect brain microwould accompany with severe neurological impairment. Our study aimed to explore the potential mechanism by employing voxel-based and surface-based morphometry to detect brain microanatomic structure alteration. METHODS The IESS group had 21 males and 13 females (mean age: 17.7 ± 15.6 months), whereas the healthy controls group had 22 males and 10 females (mean age: 29.4 ± 18.7 months). High-resolution 3D T1WI was performed. Computational Anatomy Toolbox implemented in Statistical Parametric Mapping 12 was used to measure the gray matter and white matter volume, and the cortical thickness separately. Independent sample t test was used to assess between-group differences. IESS group was assessed using the Bayley Scales of Infant Development. RESULTS The IESS group showed a significantly decreased volume of gray matter in right middle temporal gyrus, inferior temporal gyrus, superior temporal gyrus, right fusiform, and bilateral precuneus (P < 0.001). There were no significant between-group differences with respect to white matter volume or cortical thickness (P > 0.001). The results of Bayley Scales of Infant Development showed that the Mental Development Index (MDI) and Psychomotor Development Index scores of children with IESS were almost concentrated in the range of <70. MDI score showed a positive correlation with gray matter reduction area in IESS group. CONCLUSION Children with IESS had impaired cognitive and delayed motor development. And the decreased gray matter in the right temporal lobe, fusiform, and bilateral precuneus could be the potential anatomic basis for impaired function, such as hearing, visual, and language.
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Affiliation(s)
- Xiaoyu Wang
- Department of Radiology, Shenzhen Children's Hospital, Shenzhen, China
| | - Yuchun Huang
- Department of Radiology, Longhua District Shenzhen People's Hospital, Shenzhen, China
| | - Li Chen
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, China
| | - Jiahui Mai
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, China
| | - Diangang Fang
- Department of Radiology, Shenzhen Children's Hospital, Shenzhen, China
| | - Tong Mo
- Department of Radiology, Shenzhen Children's Hospital, Shenzhen, China
| | - Xinxin Qi
- China Medical University, Shenyang, China
| | - Hongwu Zeng
- Department of Radiology, Shenzhen Children's Hospital, Shenzhen, China.
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7
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Yang Q, Liu H, Zhong D, Li Z, Li J, Xiao K, Liu W. Tanc1/2 TPR domain interacts with Myo18a C-terminus and undergoes liquid-liquid phase separation. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119650. [PMID: 38092135 DOI: 10.1016/j.bbamcr.2023.119650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 11/07/2023] [Accepted: 12/01/2023] [Indexed: 12/17/2023]
Abstract
Tanc1 and its homologous protein Tanc2 are critical synaptic scaffold proteins which regulate synaptic spine densities and excitatory synapse strength. Recent studies indicated TANC1 and TANC2 are candidate genes of several neurodevelopmental disorders (NDDs). In this study, we identified and characterized a novel interaction between Tanc1/2 and Myo18a, mediated by the Tanc1/2 TPR domains and Myo18a coiled-coil domain and C-extension (CCex). Sequence analysis and size exclusion chromatography experiments reveal that high salt disrupts the interaction between Myo18a and Tanc1/2, indicating that the interaction is primarily driven by charge-charge interactions. More importantly, we found that the Tanc1-TPR/Myo18a CCex interaction could undergo liquid-liquid phase separation (LLPS) in both cultured cells and test tubes, which provides the biochemical basis and potential molecular mechanisms for the LLPS-mediated interactions between Myo18a and Tanc1/2.
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Affiliation(s)
- Qingqing Yang
- Shenzhen Key Laboratory for Neuronal Structural Biology, Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China
| | - Haiyang Liu
- Shenzhen Key Laboratory for Neuronal Structural Biology, Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China; State Key Laboratory of Molecular Neuroscience, Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Greater Bay Biomedical Innocenter, Shenzhen Bay Laboratory, Shenzhen 518055, China
| | - Dengqin Zhong
- Shenzhen Key Laboratory for Neuronal Structural Biology, Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China
| | - Zhiwei Li
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Jianchao Li
- State Key Laboratory of Molecular Neuroscience, Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Kang Xiao
- Shenzhen Key Laboratory for Neuronal Structural Biology, Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China; HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute, Futian, Shenzhen, China.
| | - Wei Liu
- Shenzhen Key Laboratory for Neuronal Structural Biology, Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China; Institute of Geriatric Medicine, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China.
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8
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Mariano V, Kanellopoulos AK, Ricci C, Di Marino D, Borrie SC, Dupraz S, Bradke F, Achsel T, Legius E, Odent S, Billuart P, Bienvenu T, Bagni C. Intellectual Disability and Behavioral Deficits Linked to CYFIP1 Missense Variants Disrupting Actin Polymerization. Biol Psychiatry 2024; 95:161-174. [PMID: 37704042 DOI: 10.1016/j.biopsych.2023.08.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/27/2023] [Accepted: 08/31/2023] [Indexed: 09/15/2023]
Abstract
BACKGROUND 15q11.2 deletions and duplications have been linked to autism spectrum disorder, schizophrenia, and intellectual disability. Recent evidence suggests that dysfunctional CYFIP1 (cytoplasmic FMR1 interacting protein 1) contributes to the clinical phenotypes observed in individuals with 15q11.2 deletion/duplication syndrome. CYFIP1 plays crucial roles in neuronal development and brain connectivity, promoting actin polymerization and regulating local protein synthesis. However, information about the impact of single nucleotide variants in CYFIP1 on neurodevelopmental disorders is limited. METHODS Here, we report a family with 2 probands exhibiting intellectual disability, autism spectrum disorder, spastic tetraparesis, and brain morphology defects and who carry biallelic missense point mutations in the CYFIP1 gene. We used skin fibroblasts from one of the probands, the parents, and typically developing individuals to investigate the effect of the variants on the functionality of CYFIP1. In addition, we generated Drosophila knockin mutants to address the effect of the variants in vivo and gain insight into the molecular mechanism that underlies the clinical phenotype. RESULTS Our study revealed that the 2 missense variants are in protein domains responsible for maintaining the interaction within the wave regulatory complex. Molecular and cellular analyses in skin fibroblasts from one proband showed deficits in actin polymerization. The fly model for these mutations exhibited abnormal brain morphology and F-actin loss and recapitulated the core behavioral symptoms, such as deficits in social interaction and motor coordination. CONCLUSIONS Our findings suggest that the 2 CYFIP1 variants contribute to the clinical phenotype in the probands that reflects deficits in actin-mediated brain development processes.
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Affiliation(s)
- Vittoria Mariano
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland; Department of Human Genetics, KU Leuven, Belgium
| | | | - Carlotta Ricci
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Daniele Di Marino
- Department of Life and Environmental Sciences, New York-Marche Structural Biology Center, Polytechnic University of Marche, Ancona, Italy; Department of Neuroscience, Neuronal Death and Neuroprotection Unit, Mario Negri Institute for Pharmacological Research-IRCCS, Milan, Italy
| | | | - Sebastian Dupraz
- Axonal Growth and Regeneration Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Frank Bradke
- Axonal Growth and Regeneration Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Tilmann Achsel
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Eric Legius
- Department of Human Genetics, KU Leuven, Belgium
| | - Sylvie Odent
- Service de Génétique Clinique, Centre Labellisé pour les Anomalies du Développement Ouest, Centre Hospitalier Universitaire de Rennes, Rennes, France; Institut de Génétique et Développement de Rennes, CNRS, UMR 6290, Université de Rennes, ERN-ITHACA, France
| | - Pierre Billuart
- Institut de Psychiatrie et de Neurosciences de Paris, Institut National de la Santé et de la Recherche Médicale U1266, Université de Paris Cité (UPC), Paris, France
| | - Thierry Bienvenu
- Institut de Psychiatrie et de Neurosciences de Paris, Institut National de la Santé et de la Recherche Médicale U1266, Université de Paris Cité (UPC), Paris, France
| | - Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
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9
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He H, Zhang H, Chen H, He F, Yin F, Stauber T, Zou X, Peng J. Functional analysis of two SLC9A6 frameshift variants in lymphoblastoid cells from patients with Christianson syndrome. CNS Neurosci Ther 2023; 29:4059-4069. [PMID: 37381736 PMCID: PMC10651982 DOI: 10.1111/cns.14329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/30/2023] [Accepted: 06/17/2023] [Indexed: 06/30/2023] Open
Abstract
BACKGROUND Christianson syndrome (CS) is caused by mutations in SLC9A6 and is characterized by global developmental delay, epilepsy, hyperkinesis, ataxia, microcephaly, and behavioral disorder. However, the molecular mechanism by which these SLC9A6 mutations cause CS in humans is not entirely understood, and there is no objective method to determine the pathogenicity of single SLC9A6 variants. METHODS Trio-based whole exome sequencing (WES) was carried out on two individuals with suspicion of CS. qRT-PCR, western blot analysis, filipin staining, lysosomal enzymatic assays, and electron microscopy examination, using EBV-LCLs established from the two patients, were performed. RESULTS Trio-based WES identified a hemizygous SLC9A6 c.1560dupT, p.T521Yfs*23 variant in proband 1 and a hemizygous SLC9A6 c.608delA, p.H203Lfs*10 variant in proband 2. Both children exhibited typical phenotypes associated with CS. Expression analysis in EBV-LCLs derived from the two patients showed a significant decrease in mRNA levels and no detectable normal NHE6 protein. EBV-LCLs showed a statistically significant increase in unesterified cholesterol in patient 1, but only non-significant increase in patient 2 when stained with filipin. Activities of lysosomal enzymes (β-hexosaminidase A, β-hexosaminidase A + B, β-galactosidase, galactocerebrosidase, arylsulfatase A) of EBV-LCLs did not significantly differ between the two patients and six controls. Importantly, by electron microscopy we detected an accumulation of lamellated membrane structures, deformed mitochondria, and lipid droplets in the patients' EBV-LCLs. CONCLUSIONS The SLC9A6 p.T521Yfs*23 and p.H203Lfs*10 variants in our patients result in loss of NHE6. Alterations of mitochondria and lipid metabolism may play a role in the pathogenesis of CS. Moreover, the combination of filipin staining with electron microscopy examination of patient lymphoblastoid cells can serve as a useful complementary diagnostic method for CS.
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Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya HospitalCentral South UniversityChangshaChina
- Hunan Intellectual and Developmental Disabilities Research CenterChangshaChina
| | - Huiwen Zhang
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, Shanghai Institute for Pediatric ResearchShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Hui Chen
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangChina
| | - Fang He
- Department of Pediatrics, Xiangya HospitalCentral South UniversityChangshaChina
- Hunan Intellectual and Developmental Disabilities Research CenterChangshaChina
| | - Fei Yin
- Department of Pediatrics, Xiangya HospitalCentral South UniversityChangshaChina
- Hunan Intellectual and Developmental Disabilities Research CenterChangshaChina
| | - Tobias Stauber
- Department of Human Medicine and Institute for Molecular MedicineMSH Medical School HamburgHamburgGermany
| | - Xiaomin Zou
- Department of Pediatrics, Xiangya HospitalCentral South UniversityChangshaChina
- Hunan Intellectual and Developmental Disabilities Research CenterChangshaChina
| | - Jing Peng
- Department of Pediatrics, Xiangya HospitalCentral South UniversityChangshaChina
- Hunan Intellectual and Developmental Disabilities Research CenterChangshaChina
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Tian Y, Shi Z, Cai J, Hou C, Wang X, Zhu H, Peng B, Shi K, Li X, Gong S, Chen WX. Levetiracetam may be an unsuitable choice for patients with PRRT2-associated self-limited infantile epilepsy. BMC Pediatr 2023; 23:529. [PMID: 37880614 PMCID: PMC10601096 DOI: 10.1186/s12887-023-04212-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Accepted: 07/26/2023] [Indexed: 10/27/2023] Open
Abstract
INTRODUCTION Self-limited infantile epilepsy (SeLIE) is a benign epilepsy. Previous studies have shown that monotherapy with most antiseizure medications can effectively relieve seizures in patients with SeLIE, but the efficacy of levetiracetam has not been investigated. OBJECTIVE This study aimed to investigate the efficacy of levetiracetam in the treatment of SeLIE patients with PRRT2 mutations. METHODS The clinical data of 39 SeLIE patients (21 males and 18 females, aged 4.79 ± 1.60 months) with pathogenic variants in PRRT2 or 16p11.2 microdeletion were retrospectively analyzed. Based on the use of initial antiseizure medication (ASM), the patients were classified into two groups: Levetiracetam group (LEG) and Other ASMs group (OAG). The difference of efficacy between the two groups was compared. RESULTS Among the 39 SeLIE patients, 16 were LEG (10 males and 6 females, aged 5.25 ± 2.07 months), with whom two obtained a seizure-free status (12.50%) and 14 ineffective or even deteriorated (87.50%). Among the 14 ineffective or deteriorated cases, 13 were seizure-controlled after replacing levetiracetam with other ASMs including topiramate, oxcarbazepine, lamotrigine, and valproate, and the remaining one finally achieved remission at age 3. Of the 39 patients, 23 were OAG (11 males and 12 females; aged 4.48 ± 1.12 months), of whom 22 achieved seizure remission, except for one patient who was ineffective with topiramate initially and relieved by oxcarbazepine instead. Although there were no significant differences in gender and age of onset between the two groups, the effective rate was significantly different (12.50% in LEG vs. 95.65% in OAG) (P < 0.01). CONCLUSION The findings showed that patients with SeLIE caused by the PRRT2 mutations did not benefit from the use of levetiracetam, but could benefit from other ASMs.
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Affiliation(s)
- Yang Tian
- The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Zhen Shi
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Jiahao Cai
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Chi Hou
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Xiuying Wang
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Haixia Zhu
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Binwei Peng
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Kaili Shi
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Xiaojing Li
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Sitang Gong
- The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China.
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China.
- Department of Pediartic, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 9# Jin Sui Road, Guangzhou, 510623, China.
| | - Wen-Xiong Chen
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China.
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 9# Jin Sui Road, Guangzhou, 510623, China.
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11
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Da Silva Cardoso J, Gomes R, Abreu M, Parente Freixo J, Falcão Reis C, Garrido C. Clinical Role of Codon 87 of the CYFIP2 Gene in Early Infantile Epileptic Encephalopathy: A Clinical Case Description. Cureus 2023; 15:e35323. [PMID: 36968925 PMCID: PMC10038648 DOI: 10.7759/cureus.35323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2023] [Indexed: 02/24/2023] Open
Abstract
The diagnosis of early infantile epileptic encephalopathy (EIEE) remains challenging, and next-generation sequencing (NGS) techniques have played a key role in identifying genetic causes. Recent studies have shown an association between mutations in the CYFIP2 gene and EIEE, with 20 deleterious variants reported so far and a de novo mutational hotspot at codon 87. A male infant presented with seizures since the age of four months as well as significant developmental delay and microcephaly. The seizures were of different types, frequent and refractory to treatment, including different anticonvulsant drugs. Metabolic studies showed no significant changes. The initial electroencephalogram revealed bilateral paroxysmal activity with hemispherical diffusion. Brain MRI showed no pathological changes. Analysis of a whole exome sequencing (WES) based multigene panel for epilepsy disclosed a heterozygous CYFIP2 gene variant [c.258_266del; p.(Trp86_Ser88del)] established as de novo. We describe the case of an infant with EIEE due to a de novo heterozygous in-frame deletion of three amino acids in CYFIP2: c.258_266del; p.(Trp86_Ser88del). This in-frame deletion eliminates codon 87, a mutational hotspot associated with a particularly severe EIEE phenotype. All previous reports had missense variants with a presumably gain-of-function mechanism. The clinical picture of our patient is very similar to the ones with deleterious variants affecting codon 87 reported in the literature. Our case report is the first to describe a disease-causing in-frame deletion in CYFIP2 and reiterates a consistent genotype-phenotype correlation.
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12
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Kang M, Zhang Y, Kang HR, Kim S, Ma R, Yi Y, Lee S, Kim Y, Li H, Jin C, Lee D, Kim E, Han K. CYFIP2 p.Arg87Cys Causes Neurological Defects and Degradation of CYFIP2. Ann Neurol 2023; 93:155-163. [PMID: 36251395 DOI: 10.1002/ana.26535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 10/05/2022] [Accepted: 10/11/2022] [Indexed: 02/05/2023]
Abstract
Here, we report the generation and comprehensive characterization of a knockin mouse model for the hotspot p.Arg87Cys variant of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) gene, which was recently identified in individuals diagnosed with West syndrome, a developmental and epileptic encephalopathy. The Cyfip2+/R87C mice recapitulated many neurological and neurobehavioral phenotypes of the patients, including spasmlike movements, microcephaly, and impaired social communication. Age-progressive cytoarchitectural disorganization and gliosis were also identified in the hippocampus of Cyfip2+/R87C mice. Beyond identifying a decrease in CYFIP2 protein levels in the Cyfip2+/R87C brains, we demonstrated that the p.Arg87Cys variant enhances ubiquitination and proteasomal degradation of CYFIP2. ANN NEUROL 2023;93:155-163.
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Affiliation(s)
- Muwon Kang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, Republic of Korea
| | - Yinhua Zhang
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyae Rim Kang
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea.,Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Seoyeong Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, Republic of Korea
| | - Ruiying Ma
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea.,Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Yunho Yi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Seungjoon Lee
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, Republic of Korea
| | - Yoonhee Kim
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
| | - Huiling Li
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea.,Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Chunmei Jin
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea.,Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Dongmin Lee
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea.,Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
| | - Eunjoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, Republic of Korea
| | - Kihoon Han
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea.,Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
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13
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Ma R, Zhang Y, Li H, Kang HR, Kim Y, Han K. Cell-autonomous reduction of CYFIP2 is insufficient to induce Alzheimer's disease-like pathologies in the hippocampal CA1 pyramidal neurons of aged mice. Anim Cells Syst (Seoul) 2023; 27:93-101. [PMID: 36999135 PMCID: PMC10044167 DOI: 10.1080/19768354.2023.2192263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/01/2023] Open
Abstract
Cytoplasmic FMR1-interacting protein 2 (CYFIP2) is an evolutionarily conserved multifunctional protein that regulates the neuronal actin cytoskeleton, mRNA translation and transport, and mitochondrial morphology and function. Supporting its critical roles in proper neuronal development and function, human genetic studies have repeatedly identified variants of the CYFIP2 gene in individuals diagnosed with neurodevelopmental disorders. Notably, a few recent studies have also suggested a mechanistic link between reduced CYFIP2 level and Alzheimer's disease (AD). Specifically, in the hippocampus of 12-month-old Cyfip2 heterozygous mice, several AD-like pathologies were identified, including increased levels of Tau phosphorylation and gliosis, and loss of dendritic spines in CA1 pyramidal neurons. However, detailed pathogenic mechanisms, such as cell types and their circuits where the pathologies originate, remain unknown for AD-like pathologies caused by CYFIP2 reduction. In this study, we aimed to address this issue by examining whether the cell-autonomous reduction of CYFIP2 in CA1 excitatory pyramidal neurons is sufficient to induce AD-like phenotypes in the hippocampus. We performed immunohistochemical, morphological, and biochemical analyses in 12-month-old Cyfip2 conditional knock-out mice, which have postnatally reduced CYFIP2 expression level in CA1, but not in CA3, excitatory pyramidal neurons of the hippocampus. Unexpectedly, we could not find any significant AD-like phenotype, suggesting that the CA1 excitatory neuron-specific reduction of CYFIP2 level is insufficient to lead to AD-like pathologies in the hippocampus. Therefore, we propose that CYFIP2 reduction in other neurons and/or their synaptic connections with CA1 pyramidal neurons may be critically involved in the hippocampal AD-like phenotypes of Cyfip2 heterozygous mice.
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Affiliation(s)
- Ruiying Ma
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Yinhua Zhang
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
| | - Huiling Li
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyae Rim Kang
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Yoonhee Kim
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
| | - Kihoon Han
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
- Kihoon Han
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14
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Galosi S, Pollini L, Novelli M, Bernardi K, Di Rocco M, Martinelli S, Leuzzi V. Motor, epileptic, and developmental phenotypes in genetic disorders affecting G protein coupled receptors-cAMP signaling. Front Neurol 2022; 13:886751. [PMID: 36003298 PMCID: PMC9393484 DOI: 10.3389/fneur.2022.886751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/13/2022] [Indexed: 11/13/2022] Open
Abstract
Over the last years, a constantly increasing number of genetic diseases associated with epilepsy and movement disorders have been recognized. An emerging group of conditions in this field is represented by genetic disorders affecting G-protein-coupled receptors (GPCRs)–cAMP signaling. This group of postsynaptic disorders includes genes encoding for proteins highly expressed in the central nervous system and involved in GPCR signal transduction and cAMP production (e.g., GNAO1, GNB1, ADCY5, GNAL, PDE2A, PDE10A, and HPCA genes). While the clinical phenotype associated with ADCY5 and GNAL is characterized by movement disorder in the absence of epilepsy, GNAO1, GNB1, PDE2A, PDE10A, and HPCA have a broader clinical phenotype, encompassing movement disorder, epilepsy, and neurodevelopmental disorders. We aimed to provide a comprehensive phenotypical characterization of genetic disorders affecting the cAMP signaling pathway, presenting with both movement disorders and epilepsy. Thus, we reviewed clinical features and genetic data of 203 patients from the literature with GNAO1, GNB1, PDE2A, PDE10A, and HPCA deficiencies. Furthermore, we delineated genotype–phenotype correlation in GNAO1 and GNB1 deficiency. This group of disorders presents with a highly recognizable clinical phenotype combining distinctive motor, epileptic, and neurodevelopmental features. A severe hyperkinetic movement disorder with potential life-threatening exacerbations and high susceptibility to a wide range of triggers is the clinical signature of the whole group of disorders. The existence of a distinctive clinical phenotype prompting diagnostic suspicion and early detection has relevant implications for clinical and therapeutic management. Studies are ongoing to clarify the pathophysiology of these rare postsynaptic disorders and start to design disease-specific treatments.
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Affiliation(s)
- Serena Galosi
- Department Human Neuroscience, Sapienza University, Rome, Italy
- *Correspondence: Serena Galosi
| | - Luca Pollini
- Department Human Neuroscience, Sapienza University, Rome, Italy
| | - Maria Novelli
- Department Human Neuroscience, Sapienza University, Rome, Italy
| | | | - Martina Di Rocco
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Simone Martinelli
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Vincenzo Leuzzi
- Department Human Neuroscience, Sapienza University, Rome, Italy
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15
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Biembengut ÍV, Shigunov P, Frota NF, Lourenzoni MR, de Souza TACB. Molecular Dynamics of CYFIP2 Protein and Its R87C Variant Related to Early Infantile Epileptic Encephalopathy. Int J Mol Sci 2022; 23:ijms23158708. [PMID: 35955843 PMCID: PMC9368851 DOI: 10.3390/ijms23158708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/29/2022] [Accepted: 07/30/2022] [Indexed: 12/05/2022] Open
Abstract
The CYFIP2 protein (cytoplasmic FMR1-interacting protein 2) is part of the WAVE regulatory complex (WRC). CYFIP2 was recently correlated to neurological disorders by the association of the R87C variant with early infantile epileptic encephalopathy (EIEE) patients. In this set of syndromes, the epileptic spasms and seizures since early childhood lead to impaired neurological development in children. Inside the WRC, the variant residue is at the CYFIP2 and WAVE1 protein interface. Thus, the hypothesis is that the R87C modification weakens this interaction, allowing the WRC complex’s constant activation. This work aimed to investigate the impacts of the mutation on the structure of the WRC complex through molecular dynamics simulation. For that, we constructed WRC models containing WAVE1-NCKAP1 proteins complexed with WT or R87C CYFIP2. Our simulations showed a flexibilization of the loop comprising residues 80–110 due to the loss of contacts between internal residues in the R87C CYFIP2 as well as the key role of residues R/C87, E624, and E689 in structural modification. These data could explain the mechanism by which the mutation impairs the stability and proper regulation of the WRC.
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Affiliation(s)
- Ísis V. Biembengut
- Laboratory for Structural and Computational Proteomics, Carlos Chagas Institute, Fundação Oswaldo Cruz Paraná (Fiocruz-PR), Curitiba 80320-290, Brazil
| | - Patrícia Shigunov
- Laboratory of Basic Biology of Stem Cells, Carlos Chagas Institute, Fundação Oswaldo Cruz Paraná (Fiocruz-PR), Curitiba 80320-290, Brazil
| | - Natalia F. Frota
- Campus do Pici (Bloco 873), Federal University of Ceara (UFC), Fortaleza 60440-970, Brazil
- Research Group on Protein Engineering and Health Solutions (GEPeSS), Fundação Oswaldo Cruz Ceará (Fiocruz-CE), São José, Precabura, Eusébio 61773-270, Brazil
| | - Marcos R. Lourenzoni
- Research Group on Protein Engineering and Health Solutions (GEPeSS), Fundação Oswaldo Cruz Ceará (Fiocruz-CE), São José, Precabura, Eusébio 61773-270, Brazil
| | - Tatiana A. C. B. de Souza
- Laboratory for Structural and Computational Proteomics, Carlos Chagas Institute, Fundação Oswaldo Cruz Paraná (Fiocruz-PR), Curitiba 80320-290, Brazil
- Correspondence:
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16
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Liu J, Chen B, Liu Y, Kong J, Zhang B, Han L, Mei D, Ma CY, Shang Q, Xie Z, Xiao M, Mei S, Zhang Y, Gao C, Li D. Paternal uniparental disomy of chromosome 16 resulting in homozygosity of a GPT2 mutation causes intellectual and developmental disability. Eur J Med Genet 2022; 65:104554. [DOI: 10.1016/j.ejmg.2022.104554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 06/16/2022] [Accepted: 06/27/2022] [Indexed: 11/16/2022]
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17
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Zhang W, Ye F, Chen S, Peng J, Pang N, Yin F. Splicing Interruption by Intron Variants in CSNK2B Causes Poirier–Bienvenu Neurodevelopmental Syndrome: A Focus on Genotype–Phenotype Correlations. Front Neurosci 2022; 16:892768. [PMID: 35774559 PMCID: PMC9237577 DOI: 10.3389/fnins.2022.892768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
CSNK2B has recently been identified as the causative gene for Poirier–Bienvenu neurodevelopmental syndrome (POBINDS). POBINDS is a rare neurodevelopmental disorder characterized by early-onset epilepsy, developmental delay, hypotonia, and dysmorphism. Limited by the scarcity of patients, the genotype–phenotype correlations in POBINDS are still unclear. In the present study, we describe the clinical and genetic characteristics of eight individuals with POBINDS, most of whom suffered developmental delay, generalized epilepsy, and hypotonia. Minigene experiments confirmed that two intron variants (c.367+5G>A and c.367+6T>C) resulted in the skipping of exon 5, leading to a premature termination of mRNA transcription. Combining our data with the available literature, the types of POBINDS-causing variants included missense, nonsense, frameshift, and splicing, but the variant types do not reflect the clinical severity. Reduced casein kinase 2 holoenzyme activity may represent a unifying pathogenesis. We also found that individuals with missense variants in the zinc finger domain had manageable seizures (p = 0.009) and milder intellectual disability (p = 0.003) than those with missense variants in other domains of CSNK2B. This is the first study of genotype–phenotype correlations in POBINDS, drawing attention to the pathogenicity of intron variants and expanding the understanding of neurodevelopmental disorders.
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Affiliation(s)
- Wen Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Fanghua Ye
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Shimeng Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- *Correspondence: Nan Pang,
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Fei Yin,
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18
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Malone TJ, Kaczmarek LK. The role of altered translation in intellectual disability and epilepsy. Prog Neurobiol 2022; 213:102267. [PMID: 35364140 PMCID: PMC10583652 DOI: 10.1016/j.pneurobio.2022.102267] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 02/18/2022] [Accepted: 03/24/2022] [Indexed: 11/29/2022]
Abstract
A very high proportion of cases of intellectual disability are genetic in origin and are associated with the occurrence of epileptic seizures during childhood. These two disorders together effect more than 5% of the world's population. One feature linking the two diseases is that learning and memory require the synthesis of new synaptic components and ion channels, while maintenance of overall excitability also requires synthesis of similar proteins in response to altered neuronal stimulation. Many of these disorders result from mutations in proteins that regulate mRNA processing, translation initiation, translation elongation, mRNA stability or upstream translation modulators. One theme that emerges on reviewing this field is that mutations in proteins that regulate changes in translation following neuronal stimulation are more likely to result in epilepsy with intellectual disability than general translation regulators with no known role in activity-dependent changes. This is consistent with the notion that activity-dependent translation in neurons differs from that in other cells types in that the changes in local cellular composition, morphology and connectivity that occur generally in response to stimuli are directly coupled to local synaptic activity and persist for months or years after the original stimulus.
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Affiliation(s)
- Taylor J Malone
- Departments of Pharmacology, and of Cellular & Molecular Physiology, Yale University, 333 Cedar Street B-309, New Haven, CT 06520, USA
| | - Leonard K Kaczmarek
- Departments of Pharmacology, and of Cellular & Molecular Physiology, Yale University, 333 Cedar Street B-309, New Haven, CT 06520, USA.
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19
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Ma R, Pang K, Kang H, Zhang Y, Bang G, Park S, Hwang E, Ryu JR, Kwon Y, Kang HR, Jin C, Kim Y, Kim SY, Kwon SK, Kim D, Sun W, Kim JY, Han K. Protein interactome and cell-type expression analyses reveal that cytoplasmic FMR1-interacting protein 1 (CYFIP1), but not CYFIP2, associates with astrocytic focal adhesion. J Neurochem 2022; 162:190-206. [PMID: 35567753 DOI: 10.1111/jnc.15622] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 02/24/2022] [Accepted: 05/11/2022] [Indexed: 11/28/2022]
Abstract
The two members of the cytoplasmic FMR1-interacting protein family, CYFIP1 and CYFIP2, are evolutionarily conserved multifunctional proteins whose defects are associated with distinct types of brain disorders. Even with high sequence homology between CYFIP1 and CYFIP2, several lines of evidence indicate their different functions in the brain; however, the underlying mechanisms remain largely unknown. Here, we performed reciprocal immunoprecipitation experiments using CYFIP1-2×Myc and CYFIP2-3×Flag knock-in mice and found that CYFIP1 and CYFIP2 are not significantly co-immunoprecipitated with each other in the knock-in brains compared to negative control wild-type brains. Moreover, CYFIP1 and CYFIP2 showed different size distributions by size-exclusion chromatography of wild-type mouse brains. Specifically, mass spectrometry-based analysis of CYFIP1-2×Myc knock-in brains identified 131 proteins in the CYFIP1 interactome. Comparison of the CYFIP1 interactome with the previously identified brain region- and age-matched CYFIP2 interactome, consisting of 140 proteins, revealed only eight common proteins. Investigations using single-cell RNA-sequencing databases suggested non-neuronal cell- and neuron-enriched expression of Cyfip1 and Cyfip2, respectively. At the protein level, CYFIP1 was detected in both neurons and astrocytes, while CYFIP2 was detected only in neurons, suggesting the predominant expression of CYFIP1 in astrocytes. Bioinformatic characterization of the CYFIP1 interactome, and co-expression analysis of Cyfip1 with astrocytic genes, commonly linked CYFIP1 with focal adhesion proteins. Immunocytochemical analysis and proximity ligation assay suggested partial co-localization of CYFIP1 and focal adhesion proteins in cultured astrocytes. Together, these results suggest a CYFIP1-specific association with astrocytic focal adhesion, which may contribute to the different brain functions and dysfunctions of CYFIP1 and CYFIP2.
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Affiliation(s)
- Ruiying Ma
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Kaifang Pang
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, 77030, USA.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, 77030, USA
| | - Hyojin Kang
- Division of National Supercomputing, Korea Institute of Science and Technology Information (KISTI), Daejeon, 34141, Republic of Korea
| | - Yinhua Zhang
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Geul Bang
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Ochang 28119, Republic of Korea.,Korea University College of Pharmacy, Sejong, 30019, Republic of Korea
| | - Sangwoo Park
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Ochang 28119, Republic of Korea
| | - Eunha Hwang
- Center for Research Equipment, Korea Basic Science Institute (KBSI), Ochang 28119, Republic of Korea
| | - Jae Ryun Ryu
- Department of Anatomy, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Yujin Kwon
- Therapeutics & Biotechnology Division, Drug discovery platform research center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114, Republic of Korea
| | - Hyae Rim Kang
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Chunmei Jin
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Yoonhee Kim
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Su Yeon Kim
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,Korea Institute of Science and Technology (KIST), Brain Science Institute, Seoul, 02792, Republic of Korea
| | - Seok-Kyu Kwon
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Seoul, 02792, Republic of Korea
| | - Doyoun Kim
- Therapeutics & Biotechnology Division, Drug discovery platform research center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114, Republic of Korea.,Medicinal Chemistry and Pharmacology, Korea University of Science and Technology (UST), Daejeon, 34113, Republic of Korea
| | - Woong Sun
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,Department of Anatomy, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Jin Young Kim
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Ochang 28119, Republic of Korea
| | - Kihoon Han
- Department of Neuroscience, Korea University College of Medicine, Seoul, 02841, Republic of Korea.,BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, 02841, Republic of Korea
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20
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Zhang W, Ye F, Pang N, Kessi M, Xiong J, Chen S, Peng J, Yang L, Yin F. Restoration of Sarco/Endoplasmic Reticulum Ca 2+-ATPase Activity Functions as a Pivotal Therapeutic Target of Anti-Glutamate-Induced Excitotoxicity to Attenuate Endoplasmic Reticulum Ca 2+ Depletion. Front Pharmacol 2022; 13:877175. [PMID: 35517826 PMCID: PMC9065279 DOI: 10.3389/fphar.2022.877175] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
Glutamate-induced excitotoxicity is a pathological basis of many acute/chronic neurodegenerative diseases. Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA2b) is a membrane-embedded P-type ATPase pump that manages the translocation of calcium ions (Ca2+) from cytosol into the lumen of the endoplasmic reticulum (ER) calcium stores. It participates in a wide range of biological functions in the central nervous system (CNS). However, the role of SERCA2b in glutamate-induced excitotoxicity and its mechanism must be elucidated. Herein, we demonstrate that SERCA2b mutants exacerbate the excitotoxicity of hypo-glutamate stimulation on HT22 cells. In this study, SERCA2b mutants accelerated Ca2+ depletion through loss-of-function (reduced pumping capacity) or gain-of-function (acquired leakage), resulting in ER stress. In addition, the occurrence of ER Ca2+ depletion increased mitochondria-associated membrane formation, which led to mitochondrial Ca2+ overload and dysfunction. Moreover, the enhancement of SERCA2b pumping capacity or inhibition of Ca2+ leakage attenuated Ca2+ depletion and impeded excitotoxicity in response to hypo-glutamate stimulation. In conclusion, SERCA2b mutants exacerbate ER Ca2+-depletion-mediated excitotoxicity in glutamate-sensitive HT22 cells. The mechanism of disruption is mainly related to the heterogeneity of SERCA2b mutation sites. Stabilization of SRECA2b function is a critical therapeutic approach against glutamate-induced excitotoxicity. These data will expand understanding of organelle regulatory networks and facilitate the discovery and creation of drugs against excitatory/inhibitory imbalance in the CNS.
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Affiliation(s)
- Wen Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Fanghua Ye
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China.,Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Juan Xiong
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Shimeng Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Li Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
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21
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Öztürk Ö, Çavdartepe BE, Bağış H. X-Linked Spinal Muscular Atrophy 2 due to a Synonymous Variant in the UBA1 Gene in a Family with Novel Findings from Turkey. Mol Syndromol 2022; 13:246-253. [PMID: 35707597 PMCID: PMC9149478 DOI: 10.1159/000519640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/14/2021] [Indexed: 11/16/2023] Open
Abstract
Spinal muscular atrophy, X-linked 2 (SMAX2) is a rare type of spinal muscular atrophy characterized by muscle weakness, hypotonia, areflexia, myopathic face, tongue fibrillations, contractures, bone fractures, and cryptorchidism. Variants of the UBA1 gene lead to SMAX2. The UBA1 gene encodes a protein that activates the ubiquitin pathway which is responsible for protein degradation. Here, we describe a family presenting with hypotonia, muscle weakness, areflexia, contractures, weak cry, in association with other anomalies including myopathic face, scoliosis, tongue fibrillations, and cryptorchidism. Molecular analysis in 2 patients revealed a hemizygous pathogenic variant in the UBA1 gene (NM_153280.3, NP_695012.1: c.1731C>T [p.Asn577Asn]) inherited from their carrier mothers. Our study presents the first patients from Turkey, widening the phenotypic spectrum of SMAX2 by pectus carinatum, medullary sponge kidney, and frontal cyst.
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Affiliation(s)
- Özden Öztürk
- Department of Medical Genetics, Medical Faculty, Adiyaman University, Adiyaman, Turkey
| | - Büşra Eser Çavdartepe
- Department of Medical Genetics, Adiyaman University Training and Research Hospital, Adiyaman, Turkey
| | - Haydar Bağış
- Department of Medical Genetics, Medical Faculty, Adiyaman University, Adiyaman, Turkey
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22
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Xiong J, Liu Z, Chen S, Kessi M, Chen B, Duan H, Deng X, Yang L, Peng J, Yin F. Correlation Analyses of Clinical Manifestations and Variant Effects in KCNB1-Related Neurodevelopmental Disorder. Front Pediatr 2022; 9:755344. [PMID: 35071126 PMCID: PMC8767024 DOI: 10.3389/fped.2021.755344] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 12/14/2021] [Indexed: 12/24/2022] Open
Abstract
Objective: Vitro functional analyses of KCNB1 variants have been done to disclose possible pathogenic mechanisms in KCNB1-related neurodevelopmental disorder. "Complete or partial loss of function (LoF)," "dominant-negative (DN) effect" are applied to describe KCNB1 variant's molecular phenotypes. The study here aimed to investigate clinical presentations and variant effects associations in the disorder. Methods: We reported 10 Chinese pediatric patients with KCNB1-related neurodevelopmental disorder here. Functional experiments on newly reported variants, including electrophysiology and protein expression, were performed in vitro. Phenotypic, functional, and genetic data in the cohort and published literature were collected. According to their variants' molecular phenotypes, patients were grouped into complete or partial LoF, and DN effect or non-dominant-negative (non-DN) effect to compare their clinical features. Results: Nine causative KCNB1 variants in 10 patients were identified in the cohort, including eight novel and one reported. Epilepsy (9/10), global developmental delay (10/10), and behavior issues (7/10) were common clinical features in our patients. Functional analyses of 8 novel variants indicated three partial and five complete LoF variants, five DN and three non-DN effect variants. Patient 1 in our series with truncated variants, whose functional results supported haploinsufficiency, had the best prognosis. Cases in complete LoF group had earlier seizure onset age (64.3 vs. 16.7%, p = 0.01) and worse seizure outcomes (18.8 vs. 66.7%, p = 0.03), and patients in DN effect subgroup had multiple seizure types compared to those in non-DN effect subgroup (65.5 vs. 30.8%, p = 0.039). Conclusion: Patients with KCNB1 variants in the Asian cohort have similar clinical manifestations to those of other races. Truncated KCNB1 variants exhibiting with haploinsufficiency molecular phenotype are linked to milder phenotypes. Individuals with complete LoF and DN effect KCNB1 variants have more severe seizure attacks than the other two subgroups.
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Affiliation(s)
- Juan Xiong
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Zhonghua Liu
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Shimeng Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Baiyu Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Haolin Duan
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Xiaolu Deng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
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23
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Hu J, Gao X, Chen L, Zhou T, Du Z, Jiang J, Wei L, Zhang Z. A novel mutation in ryanodine receptor 2 ( RYR2) genes at c.12670G>T associated with focal epilepsy in a 3-year-old child. Front Pediatr 2022; 10:1022268. [PMID: 36340715 PMCID: PMC9627620 DOI: 10.3389/fped.2022.1022268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 09/27/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Ryanodine receptor 2 (RYR2) encodes a component of a calcium channel. RYR2 variants were well-reported to be associated with catecholaminergic polymorphic ventricular tachycardia (CPVT), but rarely reported in epilepsy cases. Here, we present a novel heterozygous mutation of RYR2 in a child with focal epilepsy. METHODS At the age of 2 years and 7 months, the patient experienced seizures, such as eye closure, tooth clenching, clonic jerking and hemifacial spasm, as well as abnormal electroencephalogram (EEG). Then, he was analyzed by whole-exome sequencing (WES). The mutations of both the proband and his parents were further confirmed by Sanger sequencing. The pathogenicity of the variant was further assessed by population-based variant frequency screening, evolutionary conservation comparison, and American Association for Medical Genetics and Genomics (ACMG) scoring. RESULTS WES sequencing revealed a novel heterozygous truncating mutation [c.12670G > T, p.(Glu4224*), NM_001035.3] in RYR2 gene of the proband. Sanger sequencing confirmed that this mutation was inherited from his mother. This novel variant was predicted to be damaging by different bioinformatics methods. Cardiac investigation showed that the proband had no structural abnormalities, but sinus tachycardia. CONCLUSION We proposed that RYR2 is a potential candidate gene for focal epilepsy, and epilepsy patients carried with RYR2 variants should be given more attention, even if they do not show cardiac abnormalities.
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Affiliation(s)
- Junji Hu
- Department of Neurology, Zibo Changguo Hospital, Zibo, China
| | - Xueping Gao
- Yinfeng Gene Technology Co., Ltd., Jinan, China
| | - Longchang Chen
- Department of Neurology, Zibo Changguo Hospital, Zibo, China
| | - Tianshu Zhou
- The First Clinical College, Hubei University of Medicine, Shiyan, China
| | - Zhaoli Du
- Yinfeng Gene Technology Co., Ltd., Jinan, China
| | | | - Lei Wei
- Department of Center for Reproductive Medicine, TaiHe Hospital, Hubei University of Medicine, Shiyan, China
| | - Zhijun Zhang
- Department of Center for Reproductive Medicine, TaiHe Hospital, Hubei University of Medicine, Shiyan, China
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24
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Peng P, Kessi M, Mao L, He F, Zhang C, Chen C, Pang N, Yin F, Pan Z, Peng J. Etiologic Classification of 541 Infantile Spasms Cases: A Cohort Study. Front Pediatr 2022; 10:774828. [PMID: 35330882 PMCID: PMC8940518 DOI: 10.3389/fped.2022.774828] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To explore the etiology of infantile spasms (IS) in a large Chinese cohort based on the United States National Infantile Spasms Consortium (NISC) classification. METHODS In the present study, we recruited IS patients diagnosed at a single center (Xiangya Hospital, Central South University) between Jan 2010 and Aug 2019. Thereafter, we collected their clinical and genetic information retrospectively. Their underlying etiologies were classified according to the NISC classification and then compared in different scenarios to understand their distribution. RESULTS A total of 541 patients with IS from 18 provinces were included in this study. The underlying etiology was identified in 53.2% of the cases: structural-acquired, 25.3%; genetic, 12.9%; genetic-structural, 7.2%; structural-congenital, 5.0%; metabolic, 2.4%; infections, 0.4% and immune, 0%. Whole-exome sequencing (WES) provided the highest diagnostic yield (26.9%). In structural-acquired IS, the proportion of hypoglycemic brain injuries was significant, second only to hypoxic-ischemic encephalopathy. There was no patient discovered to have Down syndrome. STXBP1, CDKL5, TSC2, KCNQ2, IRF2BPL, and TSC1 were the most frequently implicated genes. Genetic causes were found to be the most common cause of IS in the early onset group, while structural-acquired etiologies were common in males and preterm babies. Patients with pre-spasm seizures were associated with a higher proportion of identified causes than those without. Non-acquired structural etiologies were more common in patients without hypsarrhythmia than in those with hypsarrhythmia. SIGNIFICANCE The most prevalent cause of IS was structural acquired followed by genetic causes. When brain MRI fails to detect the etiology, we propose WES as the next step. Structural-acquired IS and cases with genetic disorders are characteristic of the Chinese cohort, however, the etiology differs with the patient's age of onset, gestation age at birth, sex, and the presence/absence of both pre-spasm seizures, and hypsarrhythmia.
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Affiliation(s)
- Pan Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Leilei Mao
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Ciliu Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Chen Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Zou Pan
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
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25
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De Nittis P, Efthymiou S, Sarre A, Guex N, Chrast J, Putoux A, Sultan T, Raza Alvi J, Ur Rahman Z, Zafar F, Rana N, Rahman F, Anwar N, Maqbool S, Zaki MS, Gleeson JG, Murphy D, Galehdari H, Shariati G, Mazaheri N, Sedaghat A, Lesca G, Chatron N, Salpietro V, Christoforou M, Houlden H, Simonds WF, Pedrazzini T, Maroofian R, Reymond A. Inhibition of G-protein signalling in cardiac dysfunction of intellectual developmental disorder with cardiac arrhythmia (IDDCA) syndrome. J Med Genet 2021; 58:815-831. [PMID: 33172956 PMCID: PMC8639930 DOI: 10.1136/jmedgenet-2020-107015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 08/30/2020] [Accepted: 09/04/2020] [Indexed: 11/16/2022]
Abstract
BACKGROUND Pathogenic variants of GNB5 encoding the β5 subunit of the guanine nucleotide-binding protein cause IDDCA syndrome, an autosomal recessive neurodevelopmental disorder associated with cognitive disability and cardiac arrhythmia, particularly severe bradycardia. METHODS We used echocardiography and telemetric ECG recordings to investigate consequences of Gnb5 loss in mouse. RESULTS We delineated a key role of Gnb5 in heart sinus conduction and showed that Gnb5-inhibitory signalling is essential for parasympathetic control of heart rate (HR) and maintenance of the sympathovagal balance. Gnb5-/- mice were smaller and had a smaller heart than Gnb5+/+ and Gnb5+/- , but exhibited better cardiac function. Lower autonomic nervous system modulation through diminished parasympathetic control and greater sympathetic regulation resulted in a higher baseline HR in Gnb5-/- mice. In contrast, Gnb5-/- mice exhibited profound bradycardia on treatment with carbachol, while sympathetic modulation of the cardiac stimulation was not altered. Concordantly, transcriptome study pinpointed altered expression of genes involved in cardiac muscle contractility in atria and ventricles of knocked-out mice. Homozygous Gnb5 loss resulted in significantly higher frequencies of sinus arrhythmias. Moreover, we described 13 affected individuals, increasing the IDDCA cohort to 44 patients. CONCLUSIONS Our data demonstrate that loss of negative regulation of the inhibitory G-protein signalling causes HR perturbations in Gnb5-/- mice, an effect mainly driven by impaired parasympathetic activity. We anticipate that unravelling the mechanism of Gnb5 signalling in the autonomic control of the heart will pave the way for future drug screening.
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Affiliation(s)
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Alexandre Sarre
- Cardiovascular Assessment Facility, University of Lausanne, Lausanne, Switzerland
| | - Nicolas Guex
- Bioinformatics Competence Center, University of Lausanne, Lausanne, Switzerland
| | - Jacqueline Chrast
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Audrey Putoux
- Service de Génétique, Hopital Femme Mere Enfant, Bron, France
| | - Tipu Sultan
- Department of Pediatric Neurology, The Children's Hospital and Institute of Child Health, Lahore, Pakistan
| | - Javeria Raza Alvi
- Department of Pediatric Neurology, The Children's Hospital and Institute of Child Health, Lahore, Pakistan
| | - Zia Ur Rahman
- Department of Pediatric Neurology, The Children's Hospital and Institute of Child Health, Lahore, Pakistan
| | - Faisal Zafar
- Department of Paediatric Neurology, Children's Hospital and Institute of Child Health, Multan, Pakistan
| | - Nuzhat Rana
- Department of Paediatric Neurology, Children's Hospital and Institute of Child Health, Multan, Pakistan
| | - Fatima Rahman
- Department of Developmental-Behavioural Paediatrics, The Children's Hospital and Institute of Child Health, Lahore, Pakistan
| | - Najwa Anwar
- Department of Developmental-Behavioural Paediatrics, The Children's Hospital and Institute of Child Health, Lahore, Pakistan
| | - Shazia Maqbool
- Department of Developmental-Behavioural Paediatrics, The Children's Hospital and Institute of Child Health, Lahore, Pakistan
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Joseph G Gleeson
- Department of Neuroscience and Pediatrics, Howard Hughes Medical Institute, La Jolla, California, USA
| | - David Murphy
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Hamid Galehdari
- Department of Genetics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahwaz, Iran (the Islamic Republic of)
| | - Gholamreza Shariati
- Department of Medical Genetics, Faculty of Medicine, Ahvaz Jondishapour University of Medical Sciences, Ahvaz, Iran (the Islamic Republic of)
| | - Neda Mazaheri
- Department of Genetics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahwaz, Iran (the Islamic Republic of)
| | - Alireza Sedaghat
- Health Research Institute, Diabetes Research Center, Ahvaz Jundishapur University of medical Sciences, Ahvaz, Iran (the Islamic Republic of)
| | - Gaetan Lesca
- Service de Genetique, Hospices Civils de Lyon, Lyon, France
| | - Nicolas Chatron
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
- Service de Genetique, Hospices Civils de Lyon, Lyon, France
| | - Vincenzo Salpietro
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Marilena Christoforou
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Henry Houlden
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - William F Simonds
- Metabolic Diseases Branch/NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Thierry Pedrazzini
- Experimental Cardiology Unit, Department of Cardiovascular Medicine, University of Lausanne, Lausanne, Switzerland
| | - Reza Maroofian
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Alexandre Reymond
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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Da Silva JD, Costa MD, Almeida B, Lopes F, Maciel P, Teixeira-Castro A. Case Report: A Novel GNB1 Mutation Causes Global Developmental Delay With Intellectual Disability and Behavioral Disorders. Front Neurol 2021; 12:735549. [PMID: 34646230 PMCID: PMC8504539 DOI: 10.3389/fneur.2021.735549] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/27/2021] [Indexed: 01/26/2023] Open
Abstract
Diseases of neurodevelopment mostly exhibit neurological and psychiatric symptoms that go from very mild to extremely severe. While the etiology of most cases of neurodevelopmental disease is still unknown, the discovery of underlying genetic causes is rapidly increasing, with hundreds of genes being currently implicated as disease-causing. Here, we report a clinical case of a patient with a previously undiagnosed syndrome comprising severe global developmental delay, intellectual disability, and behavioral disorders (such as attention-deficit/hyperactivity disorder, autism spectrum disorder and recurrent bouts of aggressive behavior). After genetic testing, a pathogenic variant was detected in the GNB1 gene, which codes for the G-protein subunit β1. The detected variant (c.217G>A, p.A73T) has not been previously reported in any of the 58 published cases of GNB1 encephalopathy. However, it localizes to the mutational hotspot in exons 6 and 7 in which 88% of all missense mutations occur. An in silico model predicts that this mutation is likely to disrupt the WD40 domain of the GNB1 protein, which is required for its interaction with other G-proteins and, consequently, for downstream signal transduction. In conclusion, we reported an additional GNB1 encephalopathy patient, bearing a novel mutation, taking another step toward a better understanding of its clinical presentation and prospective development of treatments for the disease.
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Affiliation(s)
- Jorge Diogo Da Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-Portuguese Government Associate Laboratory, Braga, Guimarães, Portugal.,Pediatrics Department, Hospital of Santa Maria Maior, Barcelos, Portugal
| | - Marta Daniela Costa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-Portuguese Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Bruno Almeida
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-Portuguese Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Fátima Lopes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-Portuguese Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Patrícia Maciel
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-Portuguese Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Andreia Teixeira-Castro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-Portuguese Government Associate Laboratory, Braga, Guimarães, Portugal
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27
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Zhao A, Zhou R, Gu Q, Liu M, Zhang B, Huang J, Yang B, Yao R, Wang J, Lv H, Wang J, Shen Y, Wang H, Chen X. Trio exome sequencing identified a novel de novo WASF1 missense variant leading to recurrent site substitution in a Chinese patient with developmental delay, microcephaly, and early-onset seizures: A mutational hotspot p.Trp161 and literature review. Clin Chim Acta 2021; 523:10-18. [PMID: 34478686 DOI: 10.1016/j.cca.2021.08.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 08/28/2021] [Accepted: 08/28/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Neurodevelopmental disorder with absent language and variable seizures (NEDALVS, OMIM # 618707) is a newly described autosomal dominant condition caused by heterozygous de novo mutation in WASF1 gene. WASF1 is a key component of the WAVE regulatory complex (WRC) required for actin polymerization. So far, only 3 distinct truncating variants clustering at the WCA domain, 3 missense variants localized to the meander region and a copy number variant (CNV) of WASF1 have been identified among 11 NEDALVS cases previously reported. CASE REPORT We report a pediatric patient carrying novel de novo heterozygous missense variant (NM_003931.2: c.481T > C, p.Trp161Arg) in WASF1 gene. During the first hospitalization at age of 5.5 months, the patient was initially diagnosed with infantile spasms, developmental delay (DD) and microcephaly due to nodding-like epileptic spasms in clusters and hypsarrhythmia on video-electroencephalography, lacking head control and body rollover, and abnormal head circumference 39 cm (<-2SD). The genetic diagnosis with a causal WASF1 variant detected by trio exome sequencing indicated the rare NEDALVS. LITERATURE REVIEW All the reported NEDALVS cases published in the PubMed English literature were reviewed to summarize the genetic and phenotypic spectrum of this novel disorder. CONCLUSION We describe the third patient with a recurrently mutated amino acid site at p.Trp161 in WASF1, currently the 12th patient with NEDALVS. This hotspot missense variant and the truncating variants in WASF1 lead to similar phenotypic patterns with core features of severe DD/ID, and seizures, hypotonia, and microcephaly frequently observed. Our finding expands the WASF1 mutation spectrum and confirms the de novo hotspot missense variant at p.Trp161, further supporting the association of the novel NEDALVS with WASF1 gene and the actin regulatory pathway.
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Affiliation(s)
- Arman Zhao
- Department of Clinical Laboratory, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Rui Zhou
- Department of Neurology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Qin Gu
- Department of Rehabilitation Medicine, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Min Liu
- Department of Neurology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Bingbing Zhang
- Department of Neurology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Jing Huang
- Department of Neurology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Bin Yang
- Department of Clinical Laboratory, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Ruen Yao
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, 1678 Dongfang Road, Pudong New District, Shanghai 200127, China
| | - Jian Wang
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, 1678 Dongfang Road, Pudong New District, Shanghai 200127, China.
| | - Haitao Lv
- Department of Cardiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Jian Wang
- Department of Pediatric Surgery, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China
| | - Yiping Shen
- Department of Genetics and Metabolism, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning 530003, Guangxi, China; Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, United States.
| | - Hongying Wang
- Department of Clinical Laboratory, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China; Department of Clinical Laboratory, Children's Hospital of Wujiang District, Suzhou, 169 Park Road, Wujiang District, Suzhou 215234, Jiangsu, China.
| | - Xuqin Chen
- Department of Neurology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
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28
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Biembengut ÍV, Silva ILZ, Souza TDACBD, Shigunov P. Cytoplasmic FMR1 interacting protein (CYFIP) family members and their function in neural development and disorders. Mol Biol Rep 2021; 48:6131-6143. [PMID: 34327661 DOI: 10.1007/s11033-021-06585-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/20/2021] [Indexed: 11/25/2022]
Abstract
In humans, the cytoplasmic FMR1 interacting protein (CYFIP) family is composed of CYFIP1 and CYFIP2. Despite their high similarity and shared interaction with many partners, CYFIP1 and CYFIP2 act at different points in cellular processes. CYFIP1 and CYFIP2 have different expression levels in human tissues, and knockout animals die at different time points of development. CYFIP1, similar to CYFIP2, acts in the WAVE regulatory complex (WRC) and plays a role in actin dynamics through the activation of the Arp2/3 complex and in a posttranscriptional regulatory complex with the fragile X mental retardation protein (FMRP). Previous reports have shown that CYFIP1 and CYFIP2 may play roles in posttranscriptional regulation in different ways. While CYFIP1 is involved in translation initiation via the 5'UTR, CYFIP2 may regulate mRNA expression via the 3'UTR. In addition, this CYFIP protein family is involved in neural development and maturation as well as in different neural disorders, such as intellectual disabilities, autistic spectrum disorders, and Alzheimer's disease. In this review, we map diverse studies regarding the functions, regulation, and implications of CYFIP proteins in a series of molecular pathways. We also highlight mutations and their structural effects both in functional studies and in neural diseases.
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Affiliation(s)
- Ísis Venturi Biembengut
- Carlos Chagas Institute-FIOCRUZ-PR, Rua Prof. Algacyr Munhoz Mader, 3775, CIC, Curitiba, Paraná, 81830-010, Brazil
| | | | | | - Patrícia Shigunov
- Carlos Chagas Institute-FIOCRUZ-PR, Rua Prof. Algacyr Munhoz Mader, 3775, CIC, Curitiba, Paraná, 81830-010, Brazil.
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29
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Saini AG, Sankhyan N, Vyas S. PLEKHG2-associated neurological disorder. BMJ Case Rep 2021; 14:14/7/e244206. [PMID: 34326120 PMCID: PMC8323387 DOI: 10.1136/bcr-2021-244206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Arushi Gahlot Saini
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Naveen Sankhyan
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Sameer Vyas
- Department of Radiodiagnosis, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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30
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Xiong J, Duan H, Chen S, Kessi M, He F, Deng X, Zhang C, Yang L, Peng J, Yin F. Familial SYN1 variants related neurodevelopmental disorders in Asian pediatric patients. BMC Med Genomics 2021; 14:182. [PMID: 34243774 PMCID: PMC8272254 DOI: 10.1186/s12920-021-01028-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 06/22/2021] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND SYN1 encodes synapsin I, which is a neuronal phosphoprotein involving in regulating axonogenesis and synaptogenesis. Variants in the gene have been associated with X-linked neurodevelopmental disorders in recent years. METHODS In the study, we reported two male patients with familial SYN1 variants related neurodevelopmental disorders from Asian population. Previously published cases with significant SYN1 variants from the literature were also included to analyze the phenotype and genotype of the disorder. RESULTS Two maternally inherited SYN1 variants, including c.C1076A, p.T359K in proband A and c.C1444T, p. Q482X in proband B (NM_133499) were found, which have never been described in detail. Combining with our research, all reported probands were male in the condition, whose significant SYN1 variants were inherited from their asymptomatic or mild affected mother. Although the disorder encompasses three main clinical presentations: mental deficiency, easily controlled reflex seizure and behavior problems, patients' clinical manifestations vary in genders and individuals, even in the same pedigree. CONCLUSION We firstly reported two familial SYN1-related neurodevelopmental disorders in Asian pediatric patients. Gender and phenotype differences should be highly valued in the disorder.
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Affiliation(s)
- Juan Xiong
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Haolin Duan
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Shimeng Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Xiaolu Deng
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Ciliu Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Li Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, No. 86, Xiangya Road, Kaifu District, Changsha, 410008, China.
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China.
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31
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Lansdon LA, Fleming EA, Viso FD, Sullivan BR, Saunders CJ. Second patient with GNB2-related neurodevelopmental disease: Further evidence for a gene-disease association. Eur J Med Genet 2021; 64:104243. [PMID: 33971351 DOI: 10.1016/j.ejmg.2021.104243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 04/28/2021] [Accepted: 05/02/2021] [Indexed: 11/30/2022]
Abstract
G-proteins are ubiquitously expressed heterotrimeric proteins consisting of α, β and γ subunits and mediate G-protein coupled receptor signalling cascades. The β subunit is encoded by one of five highly similar paralogs (GNB1-GNB5, accordingly). The developmental importance of G-proteins is highlighted by the clinical relevance of variants in genes such as GNB1, which cause severe neurodevelopmental disease (NDD). Recently the candidacy of GNB2 was raised in association with NDD in an individual with a de novo variant affecting a codon conserved across paralogs and recurrently mutated in GNB1-related disease, c.229G>A p.(Gly77Arg), in association with global developmental delay, intellectual disability and dysmorphic features. Here, we report a patient with strikingly similar facial features and NDD in association with a de novo GNB2 variant affecting the same codon, c.229G>T p.(Gly77Trp). In addition, this individual has epilepsy and overgrowth. Our report is the second to implicate a de novo GNB2 variant with a severe yet variable NDD.
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Affiliation(s)
- Lisa A Lansdon
- Department of Pathology and Laboratory Medicine, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA; Genomic Medicine Center, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA
| | - Emily A Fleming
- Division of Clinical Genetics, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA
| | - Florencia Del Viso
- Department of Pathology and Laboratory Medicine, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA; Genomic Medicine Center, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA
| | - Bonnie R Sullivan
- Division of Clinical Genetics, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA; University of Missouri-Kansas City, School of Medicine, 2411 Holmes Street, Kansas City, MO, USA
| | - Carol J Saunders
- Department of Pathology and Laboratory Medicine, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA; Genomic Medicine Center, Children's Mercy-Kansas City, 2401 Gillham Road, Kansas City, MO, USA; University of Missouri-Kansas City, School of Medicine, 2411 Holmes Street, Kansas City, MO, USA.
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32
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Ma MG, Liu XR, Wu Y, Wang J, Li BM, Shi YW, Su T, Li B, Liu DT, Yi YH, Liao WP. RYR2 Mutations Are Associated With Benign Epilepsy of Childhood With Centrotemporal Spikes With or Without Arrhythmia. Front Neurosci 2021; 15:629610. [PMID: 33897349 PMCID: PMC8058200 DOI: 10.3389/fnins.2021.629610] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 02/19/2021] [Indexed: 11/13/2022] Open
Abstract
RYR2 encodes ryanodine receptor 2 protein (RYR-2) that is mainly located on endoplasmic reticulum membrane and regulates intracellular calcium concentration. The RYR-2 protein is ubiquitously distributed and highly expressed in the heart and brain. Previous studies have identified the RYR2 mutations in the etiology of arrhythmogenic right ventricular dysplasia 2 and catecholaminergic polymorphic ventricular tachycardia. However, the relationship between RYR2 gene and epilepsy is not determined. In this study, we screened for novel genetic variants in a group of 292 cases (families) with benign epilepsy of childhood with centrotemporal spikes (BECTS) by trio-based whole-exome sequencing. RYR2 mutations were identified in five cases with BECTS, including one heterozygous frameshift mutation (c.14361dup/p.Arg4790Pro fs∗6), two heterozygous missense mutations (c.2353G > A/p.Asp785Asn and c.8574G > A/p.Met2858Ile), and two pairs of compound heterozygous mutations (c.4652A > G/p.Asn1551Ser and c.11693T > C/p.Ile3898Thr, c.7469T > C/p.Val2490Ala and c.12770G > A/p.Arg4257Gln, respectively). Asp785Asn was a de novo missense mutation. All the missense mutations were suggested to be damaging by at least three web-based prediction tools. These mutations do not present or at low minor allele frequency in gnomAD database and present statistically higher frequency in the cohort of BECTS than in the control populations of gnomAD. Asp785Asn, Asn1551Ser, and Ile3898Thr were predicted to affect hydrogen bonds with surrounding amino acids. Three affected individuals had arrhythmia (sinus arrhythmia and occasional atrial premature). The two probands with compound heterozygous missense mutations presented mild cardiac structural abnormalities. Strong evidence from ClinGen Clinical Validity Framework suggested an association between RYR2 variants and epilepsy. This study suggests that RYR2 gene is potentially a candidate pathogenic gene of BECTS. More attention should be paid to epilepsy patients with RYR2 mutations, which were associated with arrhythmia and sudden unexpected death in previous reports.
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Affiliation(s)
- Mei-Gang Ma
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China.,Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Xiao-Rong Liu
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Yuan Wu
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Jie Wang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Bing-Mei Li
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Yi-Wu Shi
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Tao Su
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Bin Li
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - De-Tian Liu
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Yong-Hong Yi
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Wei-Ping Liao
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
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33
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Bose S, He H, Stauber T. Neurodegeneration Upon Dysfunction of Endosomal/Lysosomal CLC Chloride Transporters. Front Cell Dev Biol 2021; 9:639231. [PMID: 33708769 PMCID: PMC7940362 DOI: 10.3389/fcell.2021.639231] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 02/03/2021] [Indexed: 12/15/2022] Open
Abstract
The regulation of luminal ion concentrations is critical for the function of, and transport between intracellular organelles. The importance of the acidic pH in the compartments of the endosomal-lysosomal pathway has been well-known for decades. Besides the V-ATPase, which pumps protons into their lumen, a variety of ion transporters and channels is involved in the regulation of the organelles' complex ion homeostasis. Amongst these are the intracellular members of the CLC family, ClC-3 through ClC-7. They localize to distinct but overlapping compartments of the endosomal-lysosomal pathway, partially with tissue-specific expression. Functioning as 2Cl−/H+ exchangers, they can support the vesicular acidification and accumulate luminal Cl−. Mutations in the encoding genes in patients and mouse models underlie severe phenotypes including kidney stones with CLCN5 and osteopetrosis or hypopigmentation with CLCN7. Dysfunction of those intracellular CLCs that are expressed in neurons lead to neuronal defects. Loss of endosomal ClC-3, which heteromerizes with ClC-4, results in neurodegeneration. Mutations in ClC-4 are associated with epileptic encephalopathy and intellectual disability. Mice lacking the late endosomal ClC-6 develop a lysosomal storage disease with reduced pain sensitivity. Human gene variants have been associated with epilepsy, and a gain-of-function mutation causes early-onset neurodegeneration. Dysfunction of the lysosomal ClC-7 leads to a lysosomal storage disease and neurodegeneration in mice and humans. Reduced luminal chloride, as well as altered calcium regulation, has been associated with lysosomal storage diseases in general. This review discusses the properties of endosomal and lysosomal Cl−/H+ exchange by CLCs and how various alterations of ion transport by CLCs impact organellar ion homeostasis and function in neurodegenerative disorders.
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Affiliation(s)
- Shroddha Bose
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Hailan He
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.,Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Tobias Stauber
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.,Department of Human Medicine and Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
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He H, Cao X, Yin F, Wu T, Stauber T, Peng J. West Syndrome Caused By a Chloride/Proton Exchange-Uncoupling CLCN6 Mutation Related to Autophagic-Lysosomal Dysfunction. Mol Neurobiol 2021; 58:2990-2999. [PMID: 33590434 DOI: 10.1007/s12035-021-02291-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 01/12/2021] [Indexed: 12/25/2022]
Abstract
Vesicular chloride/proton exchangers of the CLC family are critically involved in the function of the endosomal-lysosomal pathway. Their dysfunction leads to severe disorders including intellectual disability and epilepsy for ClC-4, Dent's disease for ClC-5, and lysosomal storage disease and osteopetrosis for ClC-7. Here, we report a de novo variant p.Glu200Ala (p.E200A; c.599A>C) of the late endosomal ClC-6, encoded by CLCN6, in a patient with West syndrome (WS), severe developmental delay, autism, movement disorder, microcephaly, facial dysmorphism, and visual impairment. Mutation of this conserved glutamate uncouples chloride transport from proton antiport by ClC-6. This affects organellar ion homeostasis and was shown to be deleterious for other CLCs. In this study, we found that upon heterologous expression, the ClC-6 E200A variant caused autophagosome accumulation and impaired the clearance of autophagosomes by blocking autophagosome-lysosome fusion. Our study provides clinical and functional support for an association between CLCN6 variants and WS. Our findings also provide novel insights into the molecular mechanisms underlying the pathogenesis of WS, suggesting an involvement of autophagic-lysosomal dysfunction.
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Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Xiaoshuang Cao
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China.,Hunan Intellectual and Developmental Disabilities Research Center, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Tenghui Wu
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany.,Institute for Molecular Medicine and Department of Human Medicine, MSH Medical School Hamburg, Am Kaiserkai 1, 20457, Hamburg, Germany
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China. .,Hunan Intellectual and Developmental Disabilities Research Center, Xiangya Road 87, Changsha, 410008, Hunan, China.
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35
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Badawi S, Ali BR. ACE2 Nascence, trafficking, and SARS-CoV-2 pathogenesis: the saga continues. Hum Genomics 2021; 15:8. [PMID: 33514423 PMCID: PMC7844112 DOI: 10.1186/s40246-021-00304-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 01/13/2021] [Indexed: 02/08/2023] Open
Abstract
With the emergence of the novel coronavirus SARS-CoV-2 since December 2019, more than 65 million cases have been reported worldwide. This virus has shown high infectivity and severe symptoms in some cases, leading to over 1.5 million deaths globally. Despite the collaborative and concerted research efforts that have been made, no effective medication for COVID-19 (coronavirus disease-2019) is currently available. SARS-CoV-2 uses the angiotensin-converting enzyme 2 (ACE2) as an initial mediator for viral attachment and host cell invasion. ACE2 is widely distributed in the human tissues including the cell surface of lung cells which represent the primary site of the infection. Inhibiting or reducing cell surface availability of ACE2 represents a promising therapy for tackling COVID-19. In this context, most ACE2-based therapeutic strategies have aimed to tackle the virus through the use of angiotensin-converting enzyme (ACE) inhibitors or neutralizing the virus by exogenous administration of ACE2, which does not directly aim to reduce its membrane availability. However, through this review, we present a different perspective focusing on the subcellular localization and trafficking of ACE2. Membrane targeting of ACE2, and shedding and cellular trafficking pathways including the internalization are not well elucidated in literature. Therefore, we hereby present an overview of the fate of newly synthesized ACE2, its post translational modifications, and what is known of its trafficking pathways. In addition, we highlight the possibility that some of the identified ACE2 missense variants might affect its trafficking efficiency and localization and hence may explain some of the observed variable severity of SARS-CoV-2 infections. Moreover, an extensive understanding of these processes is necessarily required to evaluate the potential use of ACE2 as a credible therapeutic target.
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Affiliation(s)
- Sally Badawi
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.
- Zayed Centre for Health sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.
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36
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Lansdon LA, Saunders CJ. Genotype-phenotype correlation in GNB1-related neurodevelopmental disorder: Potential association of p.Leu95Pro with cleft palate. Am J Med Genet A 2021; 185:1341-1343. [PMID: 33427398 DOI: 10.1002/ajmg.a.62080] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/28/2020] [Accepted: 12/30/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Lisa A Lansdon
- Department of Pathology and Laboratory Medicine, Children's Mercy-Kansas City, Kansas City, Missouri, USA.,Center for Pediatric Genomic Medicine, Children's Mercy-Kansas City, Kansas City, Missouri, USA
| | - Carol J Saunders
- Department of Pathology and Laboratory Medicine, Children's Mercy-Kansas City, Kansas City, Missouri, USA.,Center for Pediatric Genomic Medicine, Children's Mercy-Kansas City, Kansas City, Missouri, USA.,School of Medicine, University of Missouri-Kansas City, Kansas City, Missouri, USA
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37
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Polovitskaya MM, Barbini C, Martinelli D, Harms FL, Cole FS, Calligari P, Bocchinfuso G, Stella L, Ciolfi A, Niceta M, Rizza T, Shinawi M, Sisco K, Johannsen J, Denecke J, Carrozzo R, Wegner DJ, Kutsche K, Tartaglia M, Jentsch TJ. A Recurrent Gain-of-Function Mutation in CLCN6, Encoding the ClC-6 Cl -/H +-Exchanger, Causes Early-Onset Neurodegeneration. Am J Hum Genet 2020; 107:1062-1077. [PMID: 33217309 PMCID: PMC7820737 DOI: 10.1016/j.ajhg.2020.11.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/02/2020] [Indexed: 12/16/2022] Open
Abstract
Dysfunction of the endolysosomal system is often associated with neurodegenerative disease because postmitotic neurons are particularly reliant on the elimination of intracellular aggregates. Adequate function of endosomes and lysosomes requires finely tuned luminal ion homeostasis and transmembrane ion fluxes. Endolysosomal CLC Cl-/H+ exchangers function as electric shunts for proton pumping and in luminal Cl- accumulation. We now report three unrelated children with severe neurodegenerative disease, who carry the same de novo c.1658A>G (p.Tyr553Cys) mutation in CLCN6, encoding the late endosomal Cl-/H+-exchanger ClC-6. Whereas Clcn6-/- mice have only mild neuronal lysosomal storage abnormalities, the affected individuals displayed severe developmental delay with pronounced generalized hypotonia, respiratory insufficiency, and variable neurodegeneration and diffusion restriction in cerebral peduncles, midbrain, and/or brainstem in MRI scans. The p.Tyr553Cys amino acid substitution strongly slowed ClC-6 gating and increased current amplitudes, particularly at the acidic pH of late endosomes. Transfection of ClC-6Tyr553Cys, but not ClC-6WT, generated giant LAMP1-positive vacuoles that were poorly acidified. Their generation strictly required ClC-6 ion transport, as shown by transport-deficient double mutants, and depended on Cl-/H+ exchange, as revealed by combination with the uncoupling p.Glu200Ala substitution. Transfection of either ClC-6Tyr553Cys/Glu200Ala or ClC-6Glu200Ala generated slightly enlarged vesicles, suggesting that p.Glu200Ala, previously associated with infantile spasms and microcephaly, is also pathogenic. Bafilomycin treatment abrogated vacuole generation, indicating that H+-driven Cl- accumulation osmotically drives vesicle enlargement. Our work establishes mutations in CLCN6 associated with neurological diseases, whose spectrum of clinical features depends on the differential impact of the allele on ClC-6 function.
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Affiliation(s)
- Maya M Polovitskaya
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
| | - Carlo Barbini
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
| | - Diego Martinelli
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Frederike L Harms
- Institute for Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - F Sessions Cole
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Paolo Calligari
- Department of Chemical Science and Technologies, University "Tor Vergata," 00133 Rome, Italy
| | - Gianfranco Bocchinfuso
- Department of Chemical Science and Technologies, University "Tor Vergata," 00133 Rome, Italy
| | - Lorenzo Stella
- Department of Chemical Science and Technologies, University "Tor Vergata," 00133 Rome, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Teresa Rizza
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Marwan Shinawi
- Division of Genetics and Genomic Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Kathleen Sisco
- Division of Genetics and Genomic Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Jessika Johannsen
- Children's Hospital, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Jonas Denecke
- Children's Hospital, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Rosalba Carrozzo
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Daniel J Wegner
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Kerstin Kutsche
- Institute for Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy.
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany; NeuroCure Cluster of Excellence, Charité Universitätsmedizin, 10117 Berlin, Germany.
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38
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Zhang Y, Kang Hyae R, Lee SH, Kim Y, Ma R, Jin C, Lim JE, Kim S, Kang Y, Kang H, Kim SY, Kwon SK, Choi SY, Han K. Enhanced Prefrontal Neuronal Activity and Social Dominance Behavior in Postnatal Forebrain Excitatory Neuron-Specific Cyfip2 Knock-Out Mice. Front Mol Neurosci 2020; 13:574947. [PMID: 33192297 PMCID: PMC7658541 DOI: 10.3389/fnmol.2020.574947] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/29/2020] [Indexed: 02/03/2023] Open
Abstract
The cytoplasmic fragile X mental retardation 1 (FMR1)-interacting protein 2 (CYFIP2) gene is associated with epilepsy, intellectual disability (ID), and developmental delay, suggesting its critical role in proper neuronal development and function. CYFIP2 is involved in regulating cellular actin dynamics and also interacts with RNA-binding proteins. However, the adult brain function of CYFIP2 remains unclear because investigations thus far are limited to Cyfip2 heterozygous (Cyfip2+/- ) mice owing to the perinatal lethality of Cyfip2-null mice. Therefore, we generated Cyfip2 conditional knock-out (cKO) mice with reduced CYFIP2 expression in postnatal forebrain excitatory neurons (CaMKIIα-Cre). We found that in the medial prefrontal cortex (mPFC) of adult Cyfip2 cKO mice, CYFIP2 expression was decreased in both layer 2/3 (L2/3) and layer 5 (L5) neurons, unlike the L5-specific CYFIP2 reduction observed in adult Cyfip2+/- mice. Nevertheless, filamentous actin (F-actin) levels were increased only in L5 of Cyfip2 cKO mPFC possibly because of a compensatory increase in CYFIP1, the other member of CYFIP family, in L2/3 neurons. Abnormal dendritic spines on basal, but not on apical, dendrites were consistently observed in L5 neurons of Cyfip2 cKO mPFC. Meanwhile, neuronal excitability and activity were enhanced in both L2/3 and L5 neurons of Cyfip2 cKO mPFC, suggesting that CYFIP2 functions of regulating F-actin and excitability/activity may be mediated through independent mechanisms. Unexpectedly, adult Cyfip2 cKO mice did not display locomotor hyperactivity or reduced anxiety observed in Cyfip2+/- mice. Instead, both exhibited enhanced social dominance accessed by the tube test. Together, these results provide additional insights into the functions of CYFIP2 in the adult brain.
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Affiliation(s)
- Yinhua Zhang
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
| | - Rim Kang Hyae
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
| | - Seung-Hyun Lee
- Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, South Korea
| | - Yoonhee Kim
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea
| | - Ruiying Ma
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
| | - Chunmei Jin
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
| | - Ji-Eun Lim
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea
| | - Seoyeon Kim
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea
| | - Yeju Kang
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea
| | - Hyojin Kang
- Division of National Supercomputing, Korea Institute of Science and Technology Information, Daejeon, South Korea
| | - Su Yeon Kim
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Center for Functional Connectomics, Korea Institute of Science and Technology, Brain Science Institute, Seoul, South Korea
| | - Seok-Kyu Kwon
- Center for Functional Connectomics, Korea Institute of Science and Technology, Brain Science Institute, Seoul, South Korea
| | - Se-Young Choi
- Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, South Korea
| | - Kihoon Han
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
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Pavone P, Polizzi A, Marino SD, Corsello G, Falsaperla R, Marino S, Ruggieri M. West syndrome: a comprehensive review. Neurol Sci 2020; 41:3547-3562. [PMID: 32827285 PMCID: PMC7655587 DOI: 10.1007/s10072-020-04600-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 07/14/2020] [Indexed: 12/20/2022]
Abstract
Since its first clinical description (on his son) by William James West (1793–1848) in 1841, and the definition of the classical triad of (1) infantile spasms; (2) hypsarrhythmia, and (3) developmental arrest or regression as “West syndrome”, new and relevant advances have been recorded in this uncommon disorder. New approaches include terminology of clinical spasms (e.g., infantile (IS) vs. epileptic spasms (ES)), variety of clinical and electroencephalographic (EEG) features (e.g., typical ictal phenomena without EEG abnormalities), burden of developmental delay, spectrum of associated genetic abnormalities, pathogenesis, treatment options, and related outcome and prognosis. Aside the classical manifestations, IS or ES may present with atypical electroclinical phenotypes (e.g., subtle spasms; modified hypsarrhythmia) and may have their onset outside infancy. An increasing number of genes, proteins, and signaling pathways play crucial roles in the pathogenesis. This condition is currently regarded as a spectrum of disorders: the so-called infantile spasm syndrome (ISs), in association with other causal factors, including structural, infectious, metabolic, syndromic, and immunologic events, all acting on a genetic predisposing background. Hormonal therapy and ketogenic diet are widely used also in combination with (classical and recent) pharmacological drugs. Biologically targeted and gene therapies are increasingly studied. The present narrative review searched in seven electronic databases (primary MeSH terms/keywords included West syndrome, infantile spasms and infantile spasms syndrome and were coupled to 25 secondary clinical, EEG, therapeutic, outcomes, and associated conditions terms) including MEDLINE, Embase, Cochrane Central, Web of Sciences, Pubmed, Scopus, and OMIM to highlight the past knowledge and more recent advances.
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Affiliation(s)
- Piero Pavone
- Unit of Clinical Pediatrics, AOU "Policlinico", PO "G. Rodolico", University of Catania, Catania, Italy
| | - Agata Polizzi
- Chair of Pediatrics, Department of Educational Sciences, University of Catania, Catania, Italy
| | - Simona Domenica Marino
- Unit of Pediatrics, Neonatology and Neonatal Intensive Care, and Pediatric Emergency, AOU "Policlinico", PO "San Marco", University of Catania, Catania, Italy
| | - Giovanni Corsello
- Unit of Pediatrics and Neonatal Intensive Therapy, Department of Promotion of Maternal and Infantile and Internal Medicine Health, and Specialist Excellence "G. D'Alessandro", University of Palermo, Palermo, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics and Neonatal Intensive Therapy, Department of Promotion of Maternal and Infantile and Internal Medicine Health, and Specialist Excellence "G. D'Alessandro", University of Palermo, Palermo, Italy
| | - Silvia Marino
- Unit of Pediatrics, Neonatology and Neonatal Intensive Care, and Pediatric Emergency, AOU "Policlinico", PO "San Marco", University of Catania, Catania, Italy
| | - Martino Ruggieri
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, AOU "Policlinico", PO "G. Rodolico", Via S. Sofia, 87, 95128, Catania, Italy.
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40
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Lee SH, Zhang Y, Park J, Kim B, Kim Y, Lee SH, Kim GH, Huh YH, Lee B, Kim Y, Lee Y, Kim JY, Kang H, Choi SY, Jang S, Li Y, Kim S, Jin C, Pang K, Kim E, Lee Y, Kim H, Kim E, Choi JH, Kim J, Lee KJ, Choi SY, Han K. Haploinsufficiency of Cyfip2 Causes Lithium-Responsive Prefrontal Dysfunction. Ann Neurol 2020; 88:526-543. [PMID: 32562430 DOI: 10.1002/ana.25827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 05/22/2020] [Accepted: 06/14/2020] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Genetic variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) encoding an actin-regulatory protein are associated with brain disorders, including intellectual disability and epilepsy. However, specific in vivo neuronal defects and potential treatments for CYFIP2-associated brain disorders remain largely unknown. Here, we characterized Cyfip2 heterozygous (Cyfip2+/- ) mice to understand their neurobehavioral phenotypes and the underlying pathological mechanisms. Furthermore, we examined a potential treatment for such phenotypes of the Cyfip2+/- mice and specified a neuronal function mediating its efficacy. METHODS We performed behavioral analyses of Cyfip2+/- mice. We combined molecular, ultrastructural, and in vitro and in vivo electrophysiological analyses of Cyfip2+/- prefrontal neurons. We also selectively reduced CYFIP2 in the prefrontal cortex (PFC) of mice with virus injections. RESULTS Adult Cyfip2+/- mice exhibited lithium-responsive abnormal behaviors. We found increased filamentous actin, enlarged dendritic spines, and enhanced excitatory synaptic transmission and excitability in the adult Cyfip2+/- PFC that was restricted to layer 5 (L5) neurons. Consistently, adult Cyfip2+/- mice showed increased seizure susceptibility and auditory steady-state responses from the cortical electroencephalographic recordings. Among the identified prefrontal defects, lithium selectively normalized the hyperexcitability of Cyfip2+/- L5 neurons. RNA sequencing revealed reduced expression of potassium channel genes in the adult Cyfip2+/- PFC. Virus-mediated reduction of CYFIP2 in the PFC was sufficient to induce L5 hyperexcitability and lithium-responsive abnormal behavior. INTERPRETATION These results suggest that L5-specific prefrontal dysfunction, especially hyperexcitability, underlies both the pathophysiology and the lithium-mediated amelioration of neurobehavioral phenotypes in adult Cyfip2+/- mice, which can be implicated in CYFIP2-associated brain disorders. ANN NEUROL 2020;88:526-543.
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Affiliation(s)
- Seung-Hyun Lee
- Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry
| | - Yinhua Zhang
- Department of Neuroscience, College of Medicine, Korea University.,Department of Biomedical Sciences, College of Medicine, Korea University
| | - Jina Park
- Center for Neuroscience, Korea Institute of Science and Technology, Seoul
| | - Bowon Kim
- Center for Neuroscience, Korea Institute of Science and Technology, Seoul
| | - Yangsik Kim
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon.,Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon
| | - Sang Hoon Lee
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu
| | - Gyu Hyun Kim
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu
| | - Yang Hoon Huh
- Center for Electron Microscopy Research, Korea Basic Science Institute, Chungcheongbuk-do
| | - Bokyoung Lee
- Department of Neuroscience, College of Medicine, Korea University
| | - Yoonhee Kim
- Department of Neuroscience, College of Medicine, Korea University.,Department of Biomedical Sciences, College of Medicine, Korea University
| | - Yeunkum Lee
- Department of Neuroscience, College of Medicine, Korea University.,Department of Biomedical Sciences, College of Medicine, Korea University
| | - Jin Yong Kim
- Department of Biomedical Sciences, College of Medicine, Korea University.,Department of Anatomy, College of Medicine, Korea University, Seoul
| | - Hyojin Kang
- Division of National Supercomputing, Korea Institute of Science and Technology Information, Daejeon, South Korea
| | - Su-Yeon Choi
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon.,Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon
| | - Seil Jang
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon.,Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon
| | - Yan Li
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon.,Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon
| | - Shinhyun Kim
- Department of Neuroscience, College of Medicine, Korea University.,Department of Biomedical Sciences, College of Medicine, Korea University
| | - Chunmei Jin
- Department of Neuroscience, College of Medicine, Korea University.,Department of Biomedical Sciences, College of Medicine, Korea University
| | - Kaifang Pang
- Department of Pediatrics, Baylor College of Medicine.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX
| | - Eunjeong Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang
| | - Yoontae Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang
| | - Hyun Kim
- Department of Biomedical Sciences, College of Medicine, Korea University.,Department of Anatomy, College of Medicine, Korea University, Seoul
| | - Eunjoon Kim
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon.,Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon
| | - Jee Hyun Choi
- Center for Neuroscience, Korea Institute of Science and Technology, Seoul
| | - Jeongjin Kim
- Center for Neuroscience, Korea Institute of Science and Technology, Seoul
| | - Kea Joo Lee
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology, Daegu, South Korea
| | - Se-Young Choi
- Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry
| | - Kihoon Han
- Department of Neuroscience, College of Medicine, Korea University.,Department of Biomedical Sciences, College of Medicine, Korea University
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41
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Mao L, Kessi M, Peng P, He F, Zhang C, Yang L, Wu L, Yin F, Peng J. The patterns of response of 11 regimens for infantile spasms. Sci Rep 2020; 10:11509. [PMID: 32661290 PMCID: PMC7359312 DOI: 10.1038/s41598-020-68403-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 06/21/2020] [Indexed: 12/04/2022] Open
Abstract
Infantile spasms (ISs) is a devastating form of an early infantile epileptic encephalopathy. The patterns of response of multiple regimens, and the difference in response rates for the cases who receive first-line therapies on time versus those who receive them after non-first-line therapies are unknown. We performed a study involving 314 ISs cases aiming to investigate the patterns of response of 11 regimens, and the difference in response rates for the cases received first-line therapies as first two regimens versus those who received other drugs prior to first-line options. As a result, the efficacy of each regimen was: the foremost two regimens; 36.99%, third; 10.27%, fourth; 6.16%, fifth; 5.48%, and from the sixth regimen onwards, each additional regimen added ≤ 2% probability of seizure freedom. There was a statistically significant difference in seizure freedom rates between cases received first-line therapies as first or second regimen versus those who received them later. Our study revealed for the first time that in ISs cases, seizure freedom is likely to be observed within the first five regimens, and an early administration of first-line therapies is superior to non-first-line options. These results will aid in management of ISs cases.
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Affiliation(s)
- Leilei Mao
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Pan Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Ciliu Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Liwen Wu
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China. .,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China.
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42
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Lee Y, Zhang Y, Kang H, Bang G, Kim Y, Kang HR, Ma R, Jin C, Kim JY, Han K. Epilepsy- and intellectual disability-associated CYFIP2 interacts with both actin regulators and RNA-binding proteins in the neonatal mouse forebrain. Biochem Biophys Res Commun 2020; 529:1-6. [PMID: 32560809 DOI: 10.1016/j.bbrc.2020.05.221] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 05/31/2020] [Indexed: 12/29/2022]
Abstract
Variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) gene are associated with early-onset epileptic encephalopathy, intellectual disability, and developmental delay. However, the current understanding of the molecular functions of CYFIP2 is limited to those related to actin dynamics, and thus, the detailed mechanisms of CYFIP2-associated brain disorders remain largely unknown. Here, we isolated the neonatal forebrain CYFIP2 complex using newly generated Cyfip2-3×Flag knock-in mice, and performed mass spectrometry-based analyses to identify proteins in the complex. The CYFIP2 interactome, consisting of 140 proteins, contained not only the expected actin regulators but also 25 RNA-binding proteins (RBPs) including Argonaute proteins. Functionally, overexpression of brain disorder-associated CYFIP2 R87 variants, but not wild-type, inhibited stress granule formation in HeLa cells. Mechanistically, the CYFIP2 R87 variants formed intracellular clusters with Argonaute proteins under both basal and stress conditions, and thereby possibly preventing their assembly into stress granules. Beyond identifying CYFIP2 interactors in vivo, these results may provide novel insights for better understanding the molecular mechanisms of CYFIP2-associated brain disorders.
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Affiliation(s)
- Yeunkum Lee
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, 02841, South Korea
| | - Yinhua Zhang
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, 02841, South Korea
| | - Hyojin Kang
- Division of National Supercomputing, KISTI, Daejeon, 34141, South Korea
| | - Geul Bang
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang, 28119, South Korea; College of Pharmacy, Korea University, Sejong, 30019, South Korea
| | - Yoonhee Kim
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea
| | - Hyae Rim Kang
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, 02841, South Korea
| | - Ruiying Ma
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea
| | - Chunmei Jin
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, 02841, South Korea
| | - Jin Young Kim
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang, 28119, South Korea.
| | - Kihoon Han
- Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, 02841, South Korea.
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43
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Giles AC, Grill B. Roles of the HUWE1 ubiquitin ligase in nervous system development, function and disease. Neural Dev 2020; 15:6. [PMID: 32336296 PMCID: PMC7184716 DOI: 10.1186/s13064-020-00143-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 04/07/2020] [Indexed: 02/07/2023] Open
Abstract
Huwe1 is a highly conserved member of the HECT E3 ubiquitin ligase family. Here, we explore the growing importance of Huwe1 in nervous system development, function and disease. We discuss extensive progress made in deciphering how Huwe1 regulates neural progenitor proliferation and differentiation, cell migration, and axon development. We highlight recent evidence indicating that Huwe1 regulates inhibitory neurotransmission. In covering these topics, we focus on findings made using both vertebrate and invertebrate in vivo model systems. Finally, we discuss extensive human genetic studies that strongly implicate HUWE1 in intellectual disability, and heighten the importance of continuing to unravel how Huwe1 affects the nervous system.
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Affiliation(s)
- Andrew C Giles
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida, 33458, USA
| | - Brock Grill
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida, 33458, USA.
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44
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Endo W, Ikemoto S, Togashi N, Miyabayashi T, Nakajima E, Hamano SI, Shibuya M, Sato R, Takezawa Y, Okubo Y, Inui T, Kato M, Sengoku T, Ogata K, Hamanaka K, Mizuguchi T, Miyatake S, Nakashima M, Matsumoto N, Haginoya K. Phenotype-genotype correlations in patients with GNB1 gene variants, including the first three reported Japanese patients to exhibit spastic diplegia, dyskinetic quadriplegia, and infantile spasms. Brain Dev 2020; 42:199-204. [PMID: 31735425 DOI: 10.1016/j.braindev.2019.10.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 08/19/2019] [Accepted: 10/21/2019] [Indexed: 10/25/2022]
Abstract
We report the first three Japanese patients with missense variants in the GNB1 gene. Patients exhibited severe dyskinetic quadriplegia with cortical blindness and epileptic spasms, West syndrome (but with good outcomes), and hypotonic quadriplegia that later developed into spastic diplegia. Whole-exome sequencing revealed two recurrent GNB1 variants (p.Leu95Pro and p.Ile80Thr) and one novel variant (p.Ser74Leu). A recent investigation revealed large numbers of patients with GNB1 variants. Functional studies of such variants and genotype-phenotype correlation are required to enable future precision medicine.
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Affiliation(s)
- Wakaba Endo
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Satoru Ikemoto
- Division of Neurology, Saitama Children's Medical Center, Saitama 330-8777, Japan
| | - Noriko Togashi
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Takuya Miyabayashi
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Erika Nakajima
- Division of Neurology, Saitama Children's Medical Center, Saitama 330-8777, Japan
| | - Shin-Ichiro Hamano
- Division of Neurology, Saitama Children's Medical Center, Saitama 330-8777, Japan
| | - Moriei Shibuya
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Ryo Sato
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Yusuke Takezawa
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Yukimune Okubo
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Takehiko Inui
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan
| | - Mitsuhiro Kato
- Department of Pediatrics, Showa University School of Medicine, Tokyo 152-8555, Japan
| | - Toru Sengoku
- Department of Biochemistry, Graduate School of Medicine, Yokohama City University, Yokohama, Japan
| | - Kazuhiro Ogata
- Department of Biochemistry, Graduate School of Medicine, Yokohama City University, Yokohama, Japan
| | - Kohei Hamanaka
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan
| | - Takeshi Mizuguchi
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan
| | - Satoko Miyatake
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan
| | - Mitsuko Nakashima
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan; Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan
| | - Kazuhiro Haginoya
- Department of Pediatric Neurology, Miyagi Children's Hospital Hospital, Sendai 989-3126, Japan.
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45
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Zhang Y, Kang HR, Han K. Differential cell-type-expression of CYFIP1 and CYFIP2 in the adult mouse hippocampus. Anim Cells Syst (Seoul) 2019; 23:380-383. [PMID: 31853374 PMCID: PMC6913624 DOI: 10.1080/19768354.2019.1696406] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 01/04/2023] Open
Abstract
Recent molecular genetic studies have suggested that two members of the cytoplasmic FMR1-interacting protein (CYFIP) gene family, CYFIP1 and CYFIP2, are causally associated with several brain disorders. However, the clinical features of individuals with CYFIP1 and CYFIP2 variants are quite different. In addition, null mice for either Cyfip1 or Cyfip2 are lethal, indicating that these two genes cannot compensate for each other in vivo. Although these results strongly suggest that CYFIP1 and CYFIP2 have distinct functions in vivo, the detailed mechanisms underlying their differences remain enigmatic and unexplored, especially considering their high sequence homology. To address this, we analyzed a recently established mouse brain single-cell RNA sequencing (scRNAseq) database and found that Cyfip1 and Cyfip2 are dominantly expressed in non-neurons and neurons, respectively, in all tested brain regions. To validate these observations, we performed fluorescent immunohistochemistry in the adult mouse hippocampus with either a CYFIP1 or CYFIP2 antibody combined with antibodies for various cell-type-specific markers. Consistent with our analysis of the scRNAseq database, CYFIP1 signals were detected in both neurons and astrocytes, while CYFIP2 signals were mainly detected in neurons. These results suggest differential cell-type-expression of CYFIP1 and CYFIP2 in vivo, which provides novel insights into our understanding of the pathophysiology of and potential treatments for CYFIP-associated brain disorders.
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Affiliation(s)
- Yinhua Zhang
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
| | - Hyae Rim Kang
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
| | - Kihoon Han
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.,Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea
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46
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Zhang Y, Lee Y, Han K. Neuronal function and dysfunction of CYFIP2: from actin dynamics to early infantile epileptic encephalopathy. BMB Rep 2019. [PMID: 30982501 PMCID: PMC6549915 DOI: 10.5483/bmbrep.2019.52.5.097] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The cytoplasmic FMR1-interacting protein family (CYFIP1 and CYFIP2) are evolutionarily conserved proteins originally identified as binding partners of the fragile X mental retardation protein (FMRP), a messenger RNA (mRNA)-binding protein whose loss causes the fragile X syndrome. Moreover, CYFIP is a key component of the heteropentameric WAVE regulatory complex (WRC), a critical regulator of neuronal actin dynamics. Therefore, CYFIP may play key roles in regulating both mRNA translation and actin polymerization, which are critically involved in proper neuronal development and function. Nevertheless, compared to CYFIP1, neuronal function and dysfunction of CYFIP2 remain largely unknown, possibly due to the relatively less well established association between CYFIP2 and brain disorders. Despite high amino acid sequence homology between CYFIP1 and CYFIP2, several in vitro and animal model studies have suggested that CYFIP2 has some unique neuronal functions distinct from those of CYFIP1. Furthermore, recent whole-exome sequencing studies identified de novo hot spot variants of CYFIP2 in patients with early infantile epileptic encephalopathy (EIEE), clearly implicating CYFIP2 dysfunction in neurological disorders. In this review, we highlight these recent investigations into the neuronal function and dysfunction of CYFIP2, and also discuss several key questions remaining about this intriguing neuronal protein.
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Affiliation(s)
- Yinhua Zhang
- Departments of Neuroscience, and Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Korea
| | - Yeunkum Lee
- Departments of Neuroscience, and Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Korea
| | - Kihoon Han
- Departments of Neuroscience, and Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Korea
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47
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Zhong M, Liao S, Li T, Wu P, Wang Y, Wu F, Li X, Hong S, Yan L, Jiang L. Early diagnosis improving the outcome of an infant with epileptic encephalopathy with cytoplasmic FMRP interacting protein 2 mutation: Case report and literature review. Medicine (Baltimore) 2019; 98:e17749. [PMID: 31689829 PMCID: PMC7017979 DOI: 10.1097/md.0000000000017749] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
RATIONALE Early infantile epileptic encephalopathy (EIEE) 65 was recently shown to be caused by the cytoplasmic FMRP interacting protein 2 (CYFIP2) mutation. To date, only 5 cases have been reported in two articles, and all the outcomes in all cases were poor. PATIENT CONCERNS In this study, we reported an 8-month-old girl with a 1 month-long history of seizures and developmental delay. Over 1 month later, she developed epileptic spasms in clusters with hypsarrhythmia on electroencephalography. DIAGNOSIS The patient was diagnosed with EIEE 65 and trio-based whole-exome sequencing revealed a causative de novo CYFIP2 mutation c.260G >T (p.Arg87Leu). INTERVENTIONS The proband was successively treated with multiple antiepileptic drugs, including levetiracetam, phenobarbital, VitB6, topiramate, methylprednisolone, prednisone, valproic acid and vigabatrin. OUTCOMES After resistance to multiple anti-epileptic drugs over 2 months of treatment, she finally achieved seizure-free several days after vigabatrin administration and her developmental delay steadily improved. LESSONS OUR: case confirmed that CYFIP2 was the pathogenic gene of EIEE 65. We also first demonstrated vigabatrin might be effective for control of seizures and helpful for the improved outcomes of these patients.
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Affiliation(s)
- Min Zhong
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
- Qianjiang Central Hospital of Chongqing, Chongqing, China
| | - Shuang Liao
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Tingsong Li
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Peng Wu
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Yanqin Wang
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Fangrui Wu
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Xiujuan Li
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Siqi Hong
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Lisi Yan
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
| | - Li Jiang
- Department of Neurology, Children's Hospital of Chongqing Medical University
- China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Ministry of Education Key Laboratory of Child Development and Disorders
- National Clinical Research Center for Child Health and Disorders
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48
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Cheng H, Capponi S, Wakeling E, Marchi E, Li Q, Zhao M, Weng C, Piatek SG, Ahlfors H, Kleyner R, Rope A, Lumaka A, Lukusa P, Devriendt K, Vermeesch J, Posey JE, Palmer EE, Murray L, Leon E, Diaz J, Worgan L, Mallawaarachchi A, Vogt J, de Munnik SA, Dreyer L, Baynam G, Ewans L, Stark Z, Lunke S, Gonçalves AR, Soares G, Oliveira J, Fassi E, Willing M, Waugh JL, Faivre L, Riviere JB, Moutton S, Mohammed S, Payne K, Walsh L, Begtrup A, Sacoto MJG, Douglas G, Alexander N, Buckley MF, Mark PR, Adès LC, Sandaradura SA, Lupski JR, Roscioli T, Agrawal PB, Kline AD, Wang K, Timmers HTM, Lyon GJ. Missense variants in TAF1 and developmental phenotypes: challenges of determining pathogenicity. Hum Mutat 2019; 41:10.1002/humu.23936. [PMID: 31646703 PMCID: PMC7187541 DOI: 10.1002/humu.23936] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/16/2019] [Indexed: 12/26/2022]
Abstract
We recently described a new neurodevelopmental syndrome (TAF1/MRXS33 intellectual disability syndrome) (MIM# 300966) caused by pathogenic variants involving the X-linked gene TAF1, which participates in RNA polymerase II transcription. The initial study reported eleven families, and the syndrome was defined as presenting early in life with hypotonia, facial dysmorphia, and developmental delay that evolved into intellectual disability (ID) and/or autism spectrum disorder (ASD). We have now identified an additional 27 families through a genotype-first approach. Familial segregation analysis, clinical phenotyping, and bioinformatics were capitalized on to assess potential variant pathogenicity, and molecular modelling was performed for those variants falling within structurally characterized domains of TAF1. A novel phenotypic clustering approach was also applied, in which the phenotypes of affected individuals were classified using 51 standardized Human Phenotype Ontology (HPO) terms. Phenotypes associated with TAF1 variants show considerable pleiotropy and clinical variability, but prominent among previously unreported effects were brain morphological abnormalities, seizures, hearing loss, and heart malformations. Our allelic series broadens the phenotypic spectrum of TAF1/MRXS33 intellectual disability syndrome and the range of TAF1 molecular defects in humans. It also illustrates the challenges for determining the pathogenicity of inherited missense variants, particularly for genes mapping to chromosome X. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Hanyin Cheng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Simona Capponi
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Urology, Medical Faculty-University of Freiburg, Freiburg, Germany
| | - Emma Wakeling
- North West Thames Regional Genetics Service, London North West University Healthcare NHS Trust, Harrow, UK
| | - Elaine Marchi
- Institute for Basic Research in Developmental Disabilities (IBR), Staten Island, New York
| | - Quan Li
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Mengge Zhao
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Chunhua Weng
- Department of Biomedical Informatics, Columbia University Medical Center, New York, New York
| | - Stefan G. Piatek
- North East Thames Regional Genetics Laboratory, Great Ormond Street Hospital, London, UK
| | - Helena Ahlfors
- North East Thames Regional Genetics Laboratory, Great Ormond Street Hospital, London, UK
| | - Robert Kleyner
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
| | - Alan Rope
- Kaiser Permanente Center for Health Research, Portland, Oregon
- Genome Medical, South San Francisco, California
| | - Aimé Lumaka
- Department of Biomedical and Preclinical Sciences, GIGA-R, Laboratory of Human Genetics, University of Liège, Liège, Belgium
- Institut National de Recherche Biomédicale, Kinshasa, DR Congo
- Centre for Human Genetics, Faculty of Medicine, University of Kinshasa, Kinshasa, DR Congo
| | - Prosper Lukusa
- Institut National de Recherche Biomédicale, Kinshasa, DR Congo
- Centre for Human Genetics, Faculty of Medicine, University of Kinshasa, Kinshasa, DR Congo
- Centre for Human Genetics, University Hospital, University of Leuven, Leuven, Belgium
| | - Koenraad Devriendt
- Centre for Human Genetics, University Hospital, University of Leuven, Leuven, Belgium
| | - Joris Vermeesch
- Centre for Human Genetics, University Hospital, University of Leuven, Leuven, Belgium
| | - Jennifer E. Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Elizabeth E. Palmer
- Genetics of Learning Disability Service, Newcastle, New South Wales, Australia
- School of Women’s and Children’s Health, University of New South Wales, Randwick, New South Wales, Australia
| | - Lucinda Murray
- Genetics of Learning Disability Service, Newcastle, New South Wales, Australia
| | - Eyby Leon
- Rare Disease Institute, Children’s National Health System, Washington, District of Columbia
| | - Jullianne Diaz
- Rare Disease Institute, Children’s National Health System, Washington, District of Columbia
| | - Lisa Worgan
- Department of Clinical Genetics, Liverpool Hospital, Sydney, New South Wales, Australia
| | - Amali Mallawaarachchi
- Department of Clinical Genetics, Liverpool Hospital, Sydney, New South Wales, Australia
| | - Julie Vogt
- West Midlands Regional Clinical Genetics Service and Birmingham Health Partners, Birmingham Women’s and Children’s Hospitals NHS Foundation Trust, Birmingham, UK
| | - Sonja A. de Munnik
- Department of Human Genetics, Institute for Genetic and Metabolic Disease, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Lauren Dreyer
- Genetic Services of Western Australia, Undiagnosed Diseases Program, Perth, Western Australia, Australia
| | - Gareth Baynam
- Genetic Services of Western Australia, Undiagnosed Diseases Program, Perth, Western Australia, Australia
- Western Australian Register of Developmental Anomalies, Perth, Western Australia, Australia
- Institute for Immunology and Infectious Diseases, Murdoch University, Perth, Western Australia, Australia
- Telethon Kids Institute, Perth, Western Australia, Australia
- Division of Paediatrics, School of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Lisa Ewans
- Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Zornitza Stark
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
- Australian Genomics Health Alliance, Melbourne, Victoria, Australia
| | - Sebastian Lunke
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
- Australian Genomics Health Alliance, Melbourne, Victoria, Australia
| | - Ana R. Gonçalves
- Center for Medical Genetics Dr. Jacinto de Magalhāes, Hospital and University Center of Porto, Porto, Portugal
| | - Gabriela Soares
- Center for Medical Genetics Dr. Jacinto de Magalhāes, Hospital and University Center of Porto, Porto, Portugal
| | - Jorge Oliveira
- Center for Medical Genetics Dr. Jacinto de Magalhāes, Hospital and University Center of Porto, Porto, Portugal
- unIGENe, and Center for Predictive and Preventive Genetics (CGPP), Institute for Molecular and Cell Biology (IBMC), Institute of Health Research and Innovation (i3S), University of Porto, Porto, Portugal
| | - Emily Fassi
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University School of Medicine, St. Louis, Michigan
| | - Marcia Willing
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University School of Medicine, St. Louis, Michigan
| | - Jeff L. Waugh
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts
- Department of Pediatrics, Division of Pediatric Neurology, University of Texas Southwestern, Dallas, Texas
| | - Laurence Faivre
- INSERM U1231, LNC UMR1231 GAD, Burgundy University, Dijon, France
| | | | - Sebastien Moutton
- INSERM U1231, LNC UMR1231 GAD, Burgundy University, Dijon, France
- Department of Medical Genetics, Reference Center for Developmental Anomalies, Bordeaux University Hospital, Bordeaux, France
| | | | - Katelyn Payne
- Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Laurence Walsh
- Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana
| | | | | | | | | | - Michael F. Buckley
- New South Wales Health Pathology Genomic Laboratory, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Paul R. Mark
- Spectrum Health Division of Medical and Molecular Genetics, Grand Rapids, Michigan
| | - Lesley C. Adès
- Department of Paediatrics and Child Health, University of Sydney, Sydney, New South Wales, Australia
- Department of Genetics, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
| | - Sarah A. Sandaradura
- Department of Paediatrics and Child Health, University of Sydney, Sydney, New South Wales, Australia
- Department of Genetics, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
| | - James R. Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Department of Pediatrics, Texas Children’s Hospital, Houston, Texas
| | - Tony Roscioli
- New South Wales Health Pathology Genomic Laboratory, Prince of Wales Hospital, Randwick, New South Wales, Australia
- Centre for Clinical Genetics, Sydney Children’s Hospital, Randwick, New South Wales, Australia
- Neuroscience Research Australia, University of New South Wales, Sydney, New South Wales, Australia
| | - Pankaj B. Agrawal
- Divisions of Newborn Medicine and Genetics and Genomics, Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, Maryland
| | - Antonie D. Kline
- Harvey Institute for Human Genetics, Greater Baltimore Medical Center, Baltimore, Maryland
| | | | - Kai Wang
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania
| | - H. T. Marc Timmers
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Urology, Medical Faculty-University of Freiburg, Freiburg, Germany
| | - Gholson J. Lyon
- Institute for Basic Research in Developmental Disabilities (IBR), Staten Island, New York
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
- The Graduate Center, The City University of New York, New York, New York
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Lee Y, Zhang Y, Ryu JR, Kang HR, Kim D, Jin C, Kim Y, Sun W, Han K. Reduced CYFIP2 Stability by Arg87 Variants Causing Human Neurological Disorders. Ann Neurol 2019; 86:803-805. [DOI: 10.1002/ana.25598] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 07/29/2019] [Indexed: 12/23/2022]
Affiliation(s)
- Yeunkum Lee
- Department of Neuroscience, College of MedicineKorea University Seoul
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
| | - Yinhua Zhang
- Department of Neuroscience, College of MedicineKorea University Seoul
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
| | - Jae Ryun Ryu
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
- Department of Anatomy, College of MedicineKorea University Seoul
| | - Hyae Rim Kang
- Department of Neuroscience, College of MedicineKorea University Seoul
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
| | - Doyoun Kim
- Korea Research Institute of Chemical Technology Daejeon South Korea
| | - Chunmei Jin
- Department of Neuroscience, College of MedicineKorea University Seoul
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
| | - Yoonhee Kim
- Department of Neuroscience, College of MedicineKorea University Seoul
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
| | - Woong Sun
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
- Department of Anatomy, College of MedicineKorea University Seoul
| | - Kihoon Han
- Department of Neuroscience, College of MedicineKorea University Seoul
- Department of Biomedical Sciences, College of MedicineKorea University Seoul
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Yap SM, Smyth S. Ryanodine receptor 2 (RYR2) mutation: A potentially novel neurocardiac calcium channelopathy manifesting as primary generalised epilepsy. Seizure 2019; 67:11-14. [PMID: 30849713 DOI: 10.1016/j.seizure.2019.02.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 02/18/2019] [Accepted: 02/21/2019] [Indexed: 10/27/2022] Open
Abstract
PURPOSE Ryanodine receptor 2 (RYR2) mutation is well-established in the aetiology of an inherited cardiac disorder known as catecholaminergic polymorphic ventricular tachycardia (CPVT). The RYR2 receptor is expressed in cardiomyocytes, and also in the hippocampus. The RYR2 mutation has not been reported as a potential cause of adult-onset genetic generalised epilepsy (GGE). METHOD Case report. RESULTS A 32-year-old right-handed female presented with three unprovoked generalised seizures over twelve years. Electroencephalogram showed epileptiform activity which coincided with normal electrocardiogram recording. Her brother survived a cardiac arrest in his 20's and was diagnosed with CPVT and found to be heterozygous for a novel mutation in the RYR2 gene at chromosome 1q43, c.229 G > A p.(Ala77Thr). The patient inherited the same missense variant, predicted to be damaging by numerous in silico analytic tools. This mutation affects the N-terminal domain of the RYR2 receptor which plays a role in channel activation. However, the patient had repeatedly normal cardiac investigations including normal exercise stress tests. CONCLUSION We propose that the RYR2 mutation is a potentially novel neurocardiac calcium channelopathy that may manifest with either CPVT or GGE depending on selective involvement of RYR2 receptors expressed in the heart or in the brain. RYR2 mutant mice have demonstrated spontaneous EEG-positive seizures independent of cardiac arrhythmia. Whole exome sequencing analyses have identified RYR2 as a candidate gene in GGE. This case is a reminder for careful assessment of episodes of transient loss of consciousness in an individual with CPVT, so as to not mistake possible neurogenic seizure for cardiogenic syncope, carrying obvious implications for treatment.
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Affiliation(s)
- Siew Mei Yap
- Department of Neurology, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland.
| | - Shane Smyth
- Department of Neurology, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland
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