1
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Patel PA, LaConte LEW, Liang C, Cecere T, Rajan D, Srivastava S, Mukherjee K. Genetic evidence for splicing-dependent structural and functional plasticity in CASK protein. J Med Genet 2024; 61:759-768. [PMID: 38670634 PMCID: PMC11290809 DOI: 10.1136/jmg-2023-109747] [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: 11/10/2023] [Accepted: 04/14/2024] [Indexed: 04/28/2024]
Abstract
BACKGROUND Pontocerebellar hypoplasia (PCH) may present with supratentorial phenotypes and is often accompanied by microcephaly. Damaging mutations in the X-linked gene CASK produce self-limiting microcephaly with PCH in females but are often lethal in males. CASK deficiency leads to early degeneration of cerebellar granule cells but its role in other regions of the brain remains uncertain. METHOD We generated a conditional Cask knockout mice and deleted Cask ubiquitously after birth at different times. We examined the clinical features in several subjects with damaging mutations clustered in the central part of the CASK protein. We have performed phylogenetic analysis and RT-PCR to assess the splicing pattern within the same protein region and performed in silico structural analysis to examine the effect of splicing on the CASK's structure. RESULT We demonstrate that deletion of murine Cask after adulthood does not affect survival but leads to cerebellar degeneration and ataxia over time. Intriguingly, damaging hemizygous CASK mutations in boys who display microcephaly and cerebral dysfunction but without PCH are known. These mutations are present in two vertebrate-specific CASK exons. These exons are subject to alternative splicing both in forebrain and hindbrain. Inclusion of these exons differentially affects the molecular structure and hence possibly the function/s of the CASK C-terminus. CONCLUSION Loss of CASK function disproportionately affects the cerebellum. Clinical data, however, suggest that CASK may have additional vertebrate-specific function/s that play a role in the mammalian forebrain. Thus, CASK has an ancient function shared between invertebrates and vertebrates as well as novel vertebrate-specific function/s.
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Affiliation(s)
- Paras A Patel
- Fralin Biomedical Research Institute at VTC, Roanoke, Virginia, USA
| | - Leslie E W LaConte
- Fralin Biomedical Research Institute at VTC, Roanoke, Virginia, USA
- Basic Science Education, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| | - Chen Liang
- Fralin Biomedical Research Institute at VTC, Roanoke, Virginia, USA
| | - Thomas Cecere
- Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - Deepa Rajan
- University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarika Srivastava
- Fralin Biomedical Research Institute at VTC, Roanoke, Virginia, USA
- Department of Genetics, The University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Konark Mukherjee
- Fralin Biomedical Research Institute at VTC, Roanoke, Virginia, USA
- Department of Genetics, The University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
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2
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Mori T, Zhou M, Tabuchi K. Diverse Clinical Phenotypes of CASK-Related Disorders and Multiple Functional Domains of CASK Protein. Genes (Basel) 2023; 14:1656. [PMID: 37628707 PMCID: PMC10454856 DOI: 10.3390/genes14081656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 08/17/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
CASK-related disorders are a form of rare X-linked neurological diseases and most of the patients are females. They are characterized by several symptoms, including microcephaly with pontine and cerebellar hypoplasia (MICPCH), epilepsy, congenital nystagmus, and neurodevelopmental disorders. Whole-genome sequencing has identified various mutations, including nonsense and missense mutations, from patients with CASK-related disorders, revealing correlations between specific mutations and clinical phenotypes. Notably, missense mutations associated with epilepsy and intellectual disability were found throughout the whole region of the CASK protein, while missense mutations related to microcephaly and MICPCH were restricted in certain domains. To investigate the pathophysiology of CASK-related disorders, research groups have employed diverse methods, including the generation of CASK knockout mice and the supplementation of CASK to rescue the phenotypes. These approaches have yielded valuable insights into the identification of functional domains of the CASK protein associated with a specific phenotype. Additionally, recent advancements in the AI-based prediction of protein structure, such as AlphaFold2, and the application of genome-editing techniques to generate CASK mutant mice carrying missense mutations from patients with CASK-related disorders, allow us to understand the pathophysiology of CASK-related disorders in more depth and to develop novel therapeutic methods for the fundamental treatment of CASK-related disorders.
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Affiliation(s)
- Takuma Mori
- Department of Neuroinnovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Matsumoto 390-8621, Japan;
- Department of Molecular and Cellular Physiology, Shinshu University School of Medicine, Matsumoto 390-8621, Japan;
| | - Mengyun Zhou
- Department of Molecular and Cellular Physiology, Shinshu University School of Medicine, Matsumoto 390-8621, Japan;
| | - Katsuhiko Tabuchi
- Department of Neuroinnovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Matsumoto 390-8621, Japan;
- Department of Molecular and Cellular Physiology, Shinshu University School of Medicine, Matsumoto 390-8621, Japan;
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3
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Dubbs H, Ortiz-Gonzalez X, Marsh ED. Pathogenic variants in CASK: Expanding the genotype-phenotype correlations. Am J Med Genet A 2022; 188:2617-2626. [PMID: 35670295 DOI: 10.1002/ajmg.a.62863] [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: 12/27/2021] [Revised: 05/04/2022] [Accepted: 05/16/2022] [Indexed: 01/24/2023]
Abstract
Pathogenic variants in CASK, an X-linked gene that plays a role in brain development and synaptic function, are the cause of both microcephaly with pontine and cerebellar hypoplasia (MICPCH), and X-linked intellectual disability (XLID) with or without nystagmus. MICPCH is caused by loss of function variants in CASK, typically affects females, and is associated with moderate-to-severe intellectual disability (ID). Additional findings, present in about one-third of individuals, include feeding difficulties, ophthalmologic issues, hypertonicity, epilepsy, and sensorineural hearing loss. Only a few affected males with MICPCH phenotype have been reported and most have had profound developmental disability and intractable epilepsy. The XLID phenotype is typically caused by missense variants and most often manifests in males; carrier females are mildly affected or unaffected. Nystagmus is often present. In total, over 175 patients have been reported in the literature. We now report an additional 11 patients with pathogenic variants in CASK that expand these phenotypes and reported genotype-phenotype correlations.
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Affiliation(s)
- Holly Dubbs
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Xilma Ortiz-Gonzalez
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Neurology and Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Eric D Marsh
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Neurology and Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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4
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Zhang R, Jia P, Yao Y, Zhu F. Case Report: Identification of a novel CASK missense variant in a Chinese family with MICPCH. Front Genet 2022; 13:933785. [PMID: 36092876 PMCID: PMC9452731 DOI: 10.3389/fgene.2022.933785] [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: 05/01/2022] [Accepted: 07/25/2022] [Indexed: 11/13/2022] Open
Abstract
Mental retardation and microcephaly with pontine and cerebellar hypoplasia (MICPCH) is a rare genetic disorder that results in varying levels of pontocerebellar hypoplasia, microcephaly, and severe intellectual disabilities. Prior genetic analyses have identified the CASK gene as a driver of MICPCH. Herein, we analyzed a Chinese family with MICPCH. The index patient was an 8-year-old male. He and his 3-year-old brother suffered from microcephaly, pontocerebellar hypoplasia, serious mental retardation, ataxia, gait disorder, and inability to speak. Through a combination of whole-exome sequencing and subsequent Sanger sequencing, a novel X-linked missense mutation, c.1882G>C (p.D628H) in the CASK gene, was identified in two siblings, as well as their mother and grandmother, who exhibited mild mental retardation. Other family members with negative genetic testing were normal. In silico analyses indicated that this missense mutation was predicted to reduce CASK protein stability, disrupt the SRC homology 3 (SH3) domain, and abolish its function. In summary, we identified a novel missense variate in CASK associated with MICPCH. Our work facilitates the diagnosis of the disease in this family and broadens the gene variant spectrum of the CASK in MICPCH patients.
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Affiliation(s)
- Runfeng Zhang
- College of Life Sciences, Hubei Normal University, Huangshi, China
| | - Peng Jia
- Department of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yanyi Yao
- Medical Genetic Center, Maternal and Child Health Hospital of Hubei Province, Wuhan, China
- *Correspondence: Feng Zhu, ; Yanyi Yao,
| | - Feng Zhu
- Department of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Clinic Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Feng Zhu, ; Yanyi Yao,
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5
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Zhang Y, Nie Y, Mu Y, Zheng J, Xu X, Zhang F, Shu J, Liu Y. A de novo variant in CASK gene causing intellectual disability and brain hypoplasia: a case report and literature review. Ital J Pediatr 2022; 48:73. [PMID: 35550617 PMCID: PMC9097383 DOI: 10.1186/s13052-022-01248-z] [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: 03/10/2021] [Accepted: 03/17/2022] [Indexed: 12/02/2022] Open
Abstract
Background The pathogenic variation of CASK gene can cause CASK related mental disorders. The main clinical manifestations are microcephaly with pontine and cerebellar hypoplasia, X-linked mental disorders with or without nystagmus and FG syndrome. The main pathogenic mechanism is the loss of function of related protein caused by variant. We reported a Chinese male newborn with a de novo variant in CASK gene. Case presentation We present an 18-day-old baby with growth retardation and brain hypoplasia. Whole-exome sequencing was performed, which detected a hemizygous missense variant c.764G > A of CASK gene. The variant changed the 255th amino acid from Arg to His. Software based bioinformatics analyses were conducted to infer its functional effect. Conclusions In this paper, a de novo variant of CASK gene was reported. Moreover, a detailed description of all the cases described in the literature is reported. CASK variants cause a variety of clinical phenotypes. Its diagnosis is difficult due to the lack of typical clinical symptoms. Genetic testing should be performed as early as possible if this disease is suspected. This case provides an important reference for the diagnosis and treatment of future cases.
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Affiliation(s)
- Ying Zhang
- Department of Neonatology, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China.,Graduate College of Tianjin Medical University, Tianjin, China
| | - Yanyan Nie
- Department of Neonatology, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China
| | - Yu Mu
- Department of Neonatology, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China
| | - Jie Zheng
- Graduate College of Tianjin Medical University, Tianjin, China
| | - Xiaowei Xu
- Tianjin Key Laboratory of Birth Defects for Prevention and Treatment, Tianjin, China.,Tianjin Pediatric Research Institute, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China
| | - Fang Zhang
- Department of Neonatology, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China
| | - Jianbo Shu
- Tianjin Key Laboratory of Birth Defects for Prevention and Treatment, Tianjin, China. .,Tianjin Pediatric Research Institute, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China.
| | - Yang Liu
- Department of Neonatology, Tianjin Children's Hospital (Tianjin University Children's Hospital), No. 238 Longyan Road, Beichen District, Tianjin, 300134, China.
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6
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Mukherjee K, LaConte LEW, Srivastava S. The Non-Linear Path from Gene Dysfunction to Genetic Disease: Lessons from the MICPCH Mouse Model. Cells 2022; 11:1131. [PMID: 35406695 PMCID: PMC8997851 DOI: 10.3390/cells11071131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/09/2022] [Accepted: 03/24/2022] [Indexed: 11/17/2022] Open
Abstract
Most human disease manifests as a result of tissue pathology, due to an underlying disease process (pathogenesis), rather than the acute loss of specific molecular function(s). Successful therapeutic strategies thus may either target the correction of a specific molecular function or halt the disease process. For the vast majority of brain diseases, clear etiologic and pathogenic mechanisms are still elusive, impeding the discovery or design of effective disease-modifying drugs. The development of valid animal models and their proper characterization is thus critical for uncovering the molecular basis of the underlying pathobiological processes of brain disorders. MICPCH (microcephaly and pontocerebellar hypoplasia) is a monogenic condition that results from variants of an X-linked gene, CASK (calcium/calmodulin-dependent serine protein kinase). CASK variants are associated with a wide range of clinical presentations, from lethality and epileptic encephalopathies to intellectual disabilities, microcephaly, and autistic traits. We have examined CASK loss-of-function mutations in model organisms to simultaneously understand the pathogenesis of MICPCH and the molecular function/s of CASK. Our studies point to a highly complex relationship between the potential molecular function/s of CASK and the phenotypes observed in model organisms and humans. Here we discuss the implications of our observations from the pathogenesis of MICPCH as a cautionary narrative against oversimplifying molecular interpretations of data obtained from genetically modified animal models of human diseases.
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Affiliation(s)
- Konark Mukherjee
- Fralin Biomedical Research Institute at VTC, Roanoke, VA 24016, USA; (L.E.W.L.); (S.S.)
- Department of Psychiatry, Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
| | - Leslie E. W. LaConte
- Fralin Biomedical Research Institute at VTC, Roanoke, VA 24016, USA; (L.E.W.L.); (S.S.)
- Department of Basic Science Education, Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
| | - Sarika Srivastava
- Fralin Biomedical Research Institute at VTC, Roanoke, VA 24016, USA; (L.E.W.L.); (S.S.)
- Department of Internal Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
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7
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Catino G, Genovese S, Di Tommaso S, Orlando V, Petti MT, De Bernardi ML, Dallapiccola B, Novelli A, Ulgheri L, Piscopo C, Alesi V. Reciprocal Xp11.4p11.3 microdeletion/microduplication spanning USP9X, DDX3X, and CASK genes in two patients with syndromic intellectual disability. Am J Med Genet A 2022; 188:1836-1847. [PMID: 35238482 DOI: 10.1002/ajmg.a.62694] [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: 09/17/2021] [Revised: 02/02/2022] [Accepted: 02/05/2022] [Indexed: 12/13/2022]
Abstract
Only a few patients with deletions or duplications at Xp11.4, bridging USP9X, DDX3X, and CASK genes, have been described so far. Here, we report on a female harboring a de novo Xp11.4p11.3 deletion and a male with an overlapping duplication inherited from an unaffected mother, presenting with syndromic intellectual disability. We discuss the role of USP9X, DDX3X, and CASK genes in human development and describe the effects of Xp11.4 deletion and duplications in female and male patients, respectively.
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Affiliation(s)
- Giorgia Catino
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Silvia Genovese
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Silvia Di Tommaso
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Valeria Orlando
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Maria Teresa Petti
- Department of Molecular Medicine and Medical Biotechnology, University Federico II, Naples, Italy
| | | | - Bruno Dallapiccola
- Genetics and Rare Disease Research Division, Bambino Gesu Children Hospital, IRCCS, Rome, Italy
| | - Antonio Novelli
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Lucia Ulgheri
- Department of Biomedical Sciences, Clinical Genetics Service, Azienda Ospedaliero-Universitaria, Sassari, Italy
| | - Carmelo Piscopo
- Department of Molecular Medicine and Medical Biotechnology, University Federico II, Naples, Italy
| | - Viola Alesi
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
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8
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Nuovo S, Micalizzi A, Romaniello R, Arrigoni F, Ginevrino M, Casella A, Serpieri V, D'Arrigo S, Briguglio M, Salerno GG, Rossato S, Sartori S, Leuzzi V, Battini R, Ben-Zeev B, Graziano C, Mirabelli Badenier M, Brankovic V, Nardocci N, Spiegel R, Petković Ramadža D, Vento G, Marti I, Simonati A, Dipresa S, Freri E, Mazza T, Bassi MT, Bosco L, Travaglini L, Zanni G, Bertini ES, Vanacore N, Borgatti R, Valente EM. Refining the mutational spectrum and gene-phenotype correlates in pontocerebellar hypoplasia: results of a multicentric study. J Med Genet 2021; 59:399-409. [PMID: 34085948 DOI: 10.1136/jmedgenet-2020-107497] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/27/2021] [Accepted: 02/09/2021] [Indexed: 12/26/2022]
Abstract
BACKGROUND Pontocerebellar hypoplasias (PCH) comprise a group of genetically heterogeneous disorders characterised by concurrent hypoplasia of the pons and the cerebellum and variable clinical and imaging features. The current classification includes 13 subtypes, with ~20 known causative genes. Attempts have been made to delineate the phenotypic spectrum associated to specific PCH genes, yet clinical and neuroradiological features are not consistent across studies, making it difficult to define gene-specific outcomes. METHODS We performed deep clinical and imaging phenotyping in 56 probands with a neuroradiological diagnosis of PCH, who underwent NGS-based panel sequencing of PCH genes and MLPA for CASK rearrangements. Next, we conducted a phenotype-based unsupervised hierarchical cluster analysis to investigate associations between genes and specific phenotypic clusters. RESULTS A genetic diagnosis was obtained in 43 probands (77%). The most common causative gene was CASK, which accounted for nearly half cases (45%) and was mutated in females and occasionally in males. The European founder mutation p.Ala307Ser in TSEN54 and pathogenic variants in EXOSC3 accounted for 18% and 9% of cases, respectively. VLDLR, TOE1 and RARS2 were mutated in single patients. We were able to confirm only few previously reported associations, including jitteriness and clonus with TSEN54 and lower motor neuron signs with EXOSC3. When considering multiple features simultaneously, a clear association with a phenotypic cluster only emerged for EXOSC3. CONCLUSION CASK represents the major PCH causative gene in Italy. Phenotypic variability associated with the most common genetic causes of PCH is wider than previously thought, with marked overlap between CASK and TSEN54-associated disorders.
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Affiliation(s)
- Sara Nuovo
- Department of Human Neuroscience, Sapienza University of Rome, Roma, Italy
| | - Alessia Micalizzi
- Laboratory of Medical Genetics, IRCCS Bambino Gesù Children's Hospital, Roma, Italy
| | - Romina Romaniello
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Filippo Arrigoni
- Neuroimaging Lab, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Monia Ginevrino
- Laboratory of Medical Genetics, IRCCS Bambino Gesù Children's Hospital, Roma, Italy.,Istituto di Medicina Genomica, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Roma, Italy
| | - Antonella Casella
- IRCCS Mondino Foundation, Pavia, Italy.,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | | | - Stefano D'Arrigo
- Department of Developmental Neurology, Fondazione IRCCS, Istituto Neurologico Carlo Besta, Milano, Italy
| | - Marilena Briguglio
- Interdepartmental Program "Autism 0-90", "G. Martino" University Hospital of Messina, Messina, Italy
| | - Grazia Gabriella Salerno
- Child Neurology Unit, Department of Paediatrics, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
| | - Sara Rossato
- U.O.C. Pediatria, Ospedale San Bortolo, Vicenza, Italy
| | - Stefano Sartori
- Paediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University Hospital of Padova, Padova, Italy
| | - Vincenzo Leuzzi
- Department of Human Neuroscience, Sapienza University of Rome, Roma, Italy
| | - Roberta Battini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.,Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy
| | - Bruria Ben-Zeev
- Pediatric Neurology Department, The Edmond and Lilly Safra Pediatric Hospital, Sheba Medical Center, Tel Hashomer, Israel.,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Claudio Graziano
- Medical Genetics Unit, AOU Policlinico di S. Orsola, Bologna, Italy
| | - Marisol Mirabelli Badenier
- Fondazione Istituto David Chiossone Onlus, Genova, Italy.,Child Neuropsychiatry Unit, Department of Neurosciences and Rehabilitation, Istituto G. Gaslini, Genova, Italy
| | - Vesna Brankovic
- Clinic for Child Neurology and Psychiatry, University of Belgrade, Belgrade, Serbia
| | - Nardo Nardocci
- Department of Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Ronen Spiegel
- Department of Pediatrics B, Emek Medical Center, Afula, Israel.,Rappaport School of Medicine, Technion, Haifa, Israel
| | | | - Giovanni Vento
- Division of Neonatology, Department of Woman and Child Health and Public Health, Child Health Area, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Roma, Italy
| | - Itxaso Marti
- Pediatric Neurology, Hospital Universitario Donostia, Biodonostia, Universidad del País Vasco UPV-EHU, San Sebastian, Spain
| | - Alessandro Simonati
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona School of Medicine and Department of Clinical Neuroscience AOUI Verona, Verona, Italy
| | - Savina Dipresa
- Department of Medicine, Unit of Andrology and Reproductive Medicine, University of Padova, Padova, Italy
| | - Elena Freri
- Department of Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Tommaso Mazza
- Bioinformatics Unit, IRCCS Casa Sollievo della Sofferenza, S. Giovanni Rotondo, Italy
| | - Maria Teresa Bassi
- Laboratory of Molecular Biology, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Luca Bosco
- Unit of Neuromuscular and Neurodegenerative Diseases, Department of Neuroscience and Neurorehabilitation, IRCCS Bambino Gesù Children's Hospital, Roma, Italy
| | - Lorena Travaglini
- Unit of Neuromuscular and Neurodegenerative Diseases, Department of Neuroscience and Neurorehabilitation, IRCCS Bambino Gesù Children's Hospital, Roma, Italy
| | - Ginevra Zanni
- Unit of Neuromuscular and Neurodegenerative Diseases, Department of Neuroscience and Neurorehabilitation, IRCCS Bambino Gesù Children's Hospital, Roma, Italy
| | - Enrico Silvio Bertini
- Unit of Neuromuscular and Neurodegenerative Diseases, Department of Neuroscience and Neurorehabilitation, IRCCS Bambino Gesù Children's Hospital, Roma, Italy
| | - Nicola Vanacore
- National Center for Disease Prevention and Health Promotion, Italian National Institute of Health, Roma, Italy
| | - Renato Borgatti
- Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, Pavia, Italy.,Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Enza Maria Valente
- IRCCS Mondino Foundation, Pavia, Italy .,Department of Molecular Medicine, University of Pavia, Pavia, Italy
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9
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CASK related disorder: Epilepsy and developmental outcome. Eur J Paediatr Neurol 2021; 31:61-69. [PMID: 33640666 DOI: 10.1016/j.ejpn.2021.02.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 02/09/2021] [Accepted: 02/15/2021] [Indexed: 11/24/2022]
Abstract
OBJECTIVE CASK pathogenic variants are associated with variable features, as intellectual disability, optic atrophy, brainstem/cerebellar hypoplasia, and epileptic encephalopathy. Few studies describe the electroclinical features of epilepsy in patients with CASK pathogenic variants and their relationship with developmental delay. METHODS this national multicentre cohort included genetically confirmed patients with different CASK pathogenic variants. Our findings were compared with cohorts reported in the literature. RESULTS we collected 34 patients (29 females) showing from moderate (4 patients) to severe (22) and profound (8) developmental delay; all showed pontine and cerebellar hypoplasia, all except three with microcephaly. Seventeen out of 34 patients (50%) suffered from epileptic seizures, including spasms (11 patients, 32.3%), generalized (5) or focal seizures (1). In 8/17 individuals (47.1%), epilepsy started at or beyond the age of 24 months. Seven (3 males) out of the 11 children with spasms showed EEG features and a course supporting the diagnosis of a developmental and epileptic encephalopathy (DEE). Drug resistance was frequent in our cohort (52.9% of patients with epilepsy). EEG abnormalities included poorly organized background activity with diffuse or multifocal epileptiform abnormalities and sleep-activation, with possible appearance over the follow-up period. Developmental delay degree was not statistically different among patients with or without seizures but feeding difficulties were more frequent in patients with epilepsy. CONCLUSIONS epilepsy is a frequent comorbidity with a high incidence of spasms and drug resistance. Overall developmental disability does not seem to be more severe in the group of patients with epilepsy nor to be linked to specific epilepsy/EEG characteristics. A childhood onset of epilepsy is frequent, with possible worsening over time, so that serial and systematic monitoring is mandatory.
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10
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Seto T, Hamazaki T, Nishigaki S, Kudo S, Shintaku H, Ondo Y, Shimojima K, Yamamoto T. A novel CASK mutation identified in siblings exhibiting developmental disorders with/without microcephaly. Intractable Rare Dis Res 2017; 6:177-182. [PMID: 28944139 PMCID: PMC5608927 DOI: 10.5582/irdr.2017.01031] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The calcium/calmodulin-dependent serine protein kinase gene (CASK) mutations are associated with various neurological disorders; a syndrome of intellectual disability (ID) and microcephaly with pontine and cerebellar hypoplasia (MICPCH), FG syndrome, X-linked ID with/without nystagmus, epileptic encephalopathy, and autistic spectrum disorder (ASD). Next generation sequencing was performed to elucidate genetic causes in siblings exhibiting developmental disorders, and a novel CASK mutation, c.1424G>T (p.Ser475Ile), was detected in a male patient with ID, ASD, and microcephaly. Radiological examination of his brain showed no structural abnormality. The identified mutation was shared with the healthy mother and a younger sister exhibiting ASD. Although the mother showed a skewed X-chromosome inactivation (XCI) pattern, the sister showed a paradoxical XCI pattern. This would explain why this sister possessed a normal intellectual level, but showed the same ASD symptoms as the affected brother. A novel CASK mutation was identified in two siblings with ID and/or ASD, suggesting a relationship between the CASK mutation and ASD. Recently performed large molecular cohorts for patients with developmental disorders suggest that CASK is one of the genes related to developmental disorders. For better understanding of genotype-phenotype correlation in ASD cases with CASK mutations, more information should be accumulated.
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Affiliation(s)
- Toshiyuki Seto
- Department of Pediatrics, Osaka City University, Osaka, Japan
| | | | | | - Satoshi Kudo
- Department of Pediatrics, Osaka City University, Osaka, Japan
| | - Haruo Shintaku
- Department of Pediatrics, Osaka City University, Osaka, Japan
| | - Yumiko Ondo
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Keiko Shimojima
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Toshiyuki Yamamoto
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
- Address correspondence to: Dr. Toshiyuki Yamamoto, Institute of Medical Genetics, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ward, Tokyo 162-8666, Japan. E-mail:
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Leto K, Arancillo M, Becker EBE, Buffo A, Chiang C, Ding B, Dobyns WB, Dusart I, Haldipur P, Hatten ME, Hoshino M, Joyner AL, Kano M, Kilpatrick DL, Koibuchi N, Marino S, Martinez S, Millen KJ, Millner TO, Miyata T, Parmigiani E, Schilling K, Sekerková G, Sillitoe RV, Sotelo C, Uesaka N, Wefers A, Wingate RJT, Hawkes R. Consensus Paper: Cerebellar Development. CEREBELLUM (LONDON, ENGLAND) 2016; 15:789-828. [PMID: 26439486 PMCID: PMC4846577 DOI: 10.1007/s12311-015-0724-2] [Citation(s) in RCA: 256] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The development of the mammalian cerebellum is orchestrated by both cell-autonomous programs and inductive environmental influences. Here, we describe the main processes of cerebellar ontogenesis, highlighting the neurogenic strategies used by developing progenitors, the genetic programs involved in cell fate specification, the progressive changes of structural organization, and some of the better-known abnormalities associated with developmental disorders of the cerebellum.
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Affiliation(s)
- Ketty Leto
- Department of Neuroscience Rita Levi Montalcini, University of Turin, via Cherasco 15, 10026, Turin, Italy.
- Neuroscience Institute Cavalieri-Ottolenghi, University of Turin, Regione Gonzole 10, 10043, Orbassano, Torino, Italy.
| | - Marife Arancillo
- Departments of Pathology & Immunology and Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Esther B E Becker
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK
| | - Annalisa Buffo
- Department of Neuroscience Rita Levi Montalcini, University of Turin, via Cherasco 15, 10026, Turin, Italy
- Neuroscience Institute Cavalieri-Ottolenghi, University of Turin, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
| | - Chin Chiang
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN, 37232, USA
| | - Baojin Ding
- Department of Microbiology and Physiological Systems and Program in Neuroscience, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-2324, USA
| | - William B Dobyns
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA, USA
- Department of Pediatrics, Genetics Division, University of Washington, Seattle, WA, USA
| | - Isabelle Dusart
- Sorbonne Universités, Université Pierre et Marie Curie Univ Paris 06, Institut de Biologie Paris Seine, France, 75005, Paris, France
- Centre National de la Recherche Scientifique, CNRS, UMR8246, INSERM U1130, Neuroscience Paris Seine, France, 75005, Paris, France
| | - Parthiv Haldipur
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA, USA
| | - Mary E Hatten
- Laboratory of Developmental Neurobiology, The Rockefeller University, New York, NY, 10065, USA
| | - Mikio Hoshino
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo, 187-8502, Japan
| | - Alexandra L Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Daniel L Kilpatrick
- Department of Microbiology and Physiological Systems and Program in Neuroscience, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-2324, USA
| | - Noriyuki Koibuchi
- Department of Integrative Physiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Silvia Marino
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London, E1 2AT, UK
| | - Salvador Martinez
- Department Human Anatomy, IMIB-Arrixaca, University of Murcia, Murcia, Spain
| | - Kathleen J Millen
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA, USA
| | - Thomas O Millner
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London, E1 2AT, UK
| | - Takaki Miyata
- Department of Anatomy and Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Elena Parmigiani
- Department of Neuroscience Rita Levi Montalcini, University of Turin, via Cherasco 15, 10026, Turin, Italy
- Neuroscience Institute Cavalieri-Ottolenghi, University of Turin, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
| | - Karl Schilling
- Anatomie und Zellbiologie, Anatomisches Institut, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany
| | - Gabriella Sekerková
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Roy V Sillitoe
- Departments of Pathology & Immunology and Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Constantino Sotelo
- Institut de la Vision, UPMC Université de Paris 06, Paris, 75012, France
| | - Naofumi Uesaka
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Annika Wefers
- Center for Neuropathology, Ludwig-Maximilians-University, Munich, Germany
| | - Richard J T Wingate
- MRC Centre for Developmental Neurobiology, King's College London, London, UK
| | - Richard Hawkes
- Department of Cell Biology & Anatomy and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4NI, AB, Canada
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12
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X-linked intellectual disability gene CASK regulates postnatal brain growth in a non-cell autonomous manner. Acta Neuropathol Commun 2016; 4:30. [PMID: 27036546 PMCID: PMC4818453 DOI: 10.1186/s40478-016-0295-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 03/07/2016] [Indexed: 01/07/2023] Open
Abstract
The phenotypic spectrum among girls with heterozygous mutations in the X-linked intellectual disability (XLID) gene CASK (calcium/calmodulin-dependent serine protein kinase) includes postnatal microcephaly, ponto-cerebellar hypoplasia, seizures, optic nerve hypoplasia, growth retardation and hypotonia. Although CASK knockout mice were previously reported to exhibit perinatal lethality and a 3-fold increased apoptotic rate in the brain, CASK deletion was not found to affect neuronal physiology and their electrical properties. The pathogenesis of CASK associated disorders and the potential function of CASK therefore remains unknown. Here, using Cre-LoxP mediated gene excision experiments; we demonstrate that deleting CASK specifically from mouse cerebellar neurons does not alter the cerebellar architecture or function. We demonstrate that the neuron-specific deletion of CASK in mice does not cause perinatal lethality but induces severe recurrent epileptic seizures and growth retardation before the onset of adulthood. Furthermore, we demonstrate that although neuron-specific haploinsufficiency of CASK is inconsequential, the CASK mutation associated human phenotypes are replicated with high fidelity in CASK heterozygous knockout female mice (CASK(+/-)). These data suggest that CASK-related phenotypes are not purely neuronal in origin. Surprisingly, the observed microcephaly in CASK(+/-) animals is not associated with a specific loss of CASK null brain cells indicating that CASK regulates postnatal brain growth in a non-cell autonomous manner. Using biochemical assay, we also demonstrate that CASK can interact with metabolic proteins. CASK knockdown in human cell lines cause reduced cellular respiration and CASK(+/-) mice display abnormalities in muscle and brain oxidative metabolism, suggesting a novel function of CASK in metabolism. Our data implies that some phenotypic components of CASK heterozygous deletion mutation associated disorders represent systemic manifestation of metabolic stress and therefore amenable to therapeutic intervention.
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13
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Moog U, Bierhals T, Brand K, Bautsch J, Biskup S, Brune T, Denecke J, de Die-Smulders CE, Evers C, Hempel M, Henneke M, Yntema H, Menten B, Pietz J, Pfundt R, Schmidtke J, Steinemann D, Stumpel CT, Van Maldergem L, Kutsche K. Phenotypic and molecular insights into CASK-related disorders in males. Orphanet J Rare Dis 2015; 10:44. [PMID: 25886057 PMCID: PMC4449965 DOI: 10.1186/s13023-015-0256-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 03/20/2015] [Indexed: 12/05/2022] Open
Abstract
Background Heterozygous loss-of-function mutations in the X-linked CASK gene cause progressive microcephaly with pontine and cerebellar hypoplasia (MICPCH) and severe intellectual disability (ID) in females. Different CASK mutations have also been reported in males. The associated phenotypes range from nonsyndromic ID to Ohtahara syndrome with cerebellar hypoplasia. However, the phenotypic spectrum in males has not been systematically evaluated to date. Methods We identified a CASK alteration in 8 novel unrelated male patients by targeted Sanger sequencing, copy number analysis (MLPA and/or FISH) and array CGH. CASK transcripts were investigated by RT-PCR followed by sequencing. Immunoblotting was used to detect CASK protein in patient-derived cells. The clinical phenotype and natural history of the 8 patients and 28 CASK-mutation positive males reported previously were reviewed and correlated with available molecular data. Results CASK alterations include one nonsense mutation, one 5-bp deletion, one mutation of the start codon, and five partial gene deletions and duplications; seven were de novo, including three somatic mosaicisms, and one was familial. In three subjects, specific mRNA junction fragments indicated in tandem duplication of CASK exons disrupting the integrity of the gene. The 5-bp deletion resulted in multiple aberrant CASK mRNAs. In fibroblasts from patients with a CASK loss-of-function mutation, no CASK protein could be detected. Individuals who are mosaic for a severe CASK mutation or carry a hypomorphic mutation still showed detectable amount of protein. Conclusions Based on eight novel patients and all CASK-mutation positive males reported previously three phenotypic groups can be distinguished that represent a clinical continuum: (i) MICPCH with severe epileptic encephalopathy caused by hemizygous loss-of-function mutations, (ii) MICPCH associated with inactivating alterations in the mosaic state or a partly penetrant mutation, and (iii) syndromic/nonsyndromic mild to severe ID with or without nystagmus caused by CASK missense and splice mutations that leave the CASK protein intact but likely alter its function or reduce the amount of normal protein. Our findings facilitate focused testing of the CASK gene and interpreting sequence variants identified by next-generation sequencing in cases with a phenotype resembling either of the three groups. Electronic supplementary material The online version of this article (doi:10.1186/s13023-015-0256-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ute Moog
- Institute of Human Genetics, Heidelberg University, Heidelberg, Germany.
| | - Tatjana Bierhals
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Kristina Brand
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Jan Bautsch
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | | | - Thomas Brune
- Universitätskinderklinik, Universitätsklinikum Magdeburg, Magdeburg, Germany.
| | - Jonas Denecke
- Klinik und Poliklinik für Kinder- und Jugendmedizin, Neuropädiatrie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany.
| | - Christine E de Die-Smulders
- Department of Clinical Genetics and School for Oncology & Developmental Biology (GROW), Maastricht UMC+, Maastricht, The Netherlands.
| | - Christina Evers
- Institute of Human Genetics, Heidelberg University, Heidelberg, Germany.
| | - Maja Hempel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Marco Henneke
- Klinik für Kinder- und Jugendmedizin, Universitätsmedizin Göttingen, Göttingen, Germany.
| | - Helger Yntema
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Björn Menten
- Center for Medical Genetics, Ghent University, Ghent, Belgium.
| | - Joachim Pietz
- Section of Neuropediatrics, Center for Child and Adolescent Medicine, Heidelberg, Germany.
| | - Rolph Pfundt
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Jörg Schmidtke
- Institut für Humangenetik, Medizinische Hochschule Hannover, Hannover, Germany.
| | - Doris Steinemann
- Institut für Zell- und Molekularpathologie, Medizinische Hochschule Hannover, Hannover, Germany.
| | - Constance T Stumpel
- Department of Clinical Genetics and School for Oncology & Developmental Biology (GROW), Maastricht UMC+, Maastricht, The Netherlands.
| | | | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
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14
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Li Z, Schonberg R, Guidugli L, Johnson AK, Arnovitz S, Yang S, Scafidi J, Summar ML, Vezina G, Das S, Chapman K, del Gaudio D. A novel mutation in the promoter of RARS2 causes pontocerebellar hypoplasia in two siblings. J Hum Genet 2015; 60:363-9. [PMID: 25809939 DOI: 10.1038/jhg.2015.31] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 02/09/2015] [Accepted: 02/26/2015] [Indexed: 02/04/2023]
Abstract
Pontocerebellar hypoplasia (PCH) is characterized by hypoplasia and atrophy of the cerebellum, variable pontine atrophy, microcephaly, severe mental and motor impairments and seizures. Mutations in 11 genes have been reported in 8 out of 10 forms of PCH. Recessive mutations in the mitochondrial arginyl-transfer RNA synthetase gene (RARS2) have been recently associated with PCH type 6, which is characterized by early-onset encephalopathy with signs of oxidative phosphorylation defect. Here we describe the clinical presentation, neuroimaging findings and molecular characterizations of two siblings with a clinical diagnosis of PCH who displayed a novel variant (c.-2A>G) in the 5'-UTR of the RARS2 gene in the homozygous state. This variant was identified through next-generation sequencing testing of a panel of nine genes known to be involved in PCH. Gene expression and functional studies demonstrated that the c.-2A>G sequence change directly leads to a reduced RARS2 messenger RNA expression in the patients by decreasing RARS2 promoter activity, thus providing evidence that mutations in the RARS2 promoter are likely to represent a new causal mechanism of PCH6.
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Affiliation(s)
- Zejuan Li
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Rhonda Schonberg
- 1] Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA [2] The George Washington University Medical Center, Washington, DC, USA
| | - Lucia Guidugli
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | | | - Stephen Arnovitz
- Section of Hematology/Oncology, Department of Medicine, University of Chicago, Chicago, IL, USA
| | - Sandra Yang
- Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA
| | - Joseph Scafidi
- 1] The George Washington University Medical Center, Washington, DC, USA [2] Division of Neurology, Children's National Health System, Washington, DC, USA
| | - Marshall L Summar
- 1] Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA [2] The George Washington University Medical Center, Washington, DC, USA
| | - Gilbert Vezina
- 1] The George Washington University Medical Center, Washington, DC, USA [2] Department of Radiology, Children's National Health System, Washington, DC, USA
| | - Soma Das
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Kimberly Chapman
- 1] Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA [2] The George Washington University Medical Center, Washington, DC, USA
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LaConte LEW, Chavan V, Mukherjee K. Identification and glycerol-induced correction of misfolding mutations in the X-linked mental retardation gene CASK. PLoS One 2014; 9:e88276. [PMID: 24505460 PMCID: PMC3914952 DOI: 10.1371/journal.pone.0088276] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 01/09/2014] [Indexed: 11/21/2022] Open
Abstract
The overwhelming amount of available genomic sequence variation information demands a streamlined approach to examine known pathogenic mutations of any given protein. Here we seek to outline a strategy to easily classify pathogenic missense mutations that cause protein misfolding and are thus good candidates for chaperone-based therapeutic strategies, using previously identified mutations in the gene CASK. We applied a battery of bioinformatics algorithms designed to predict potential impact on protein structure to five pathogenic missense mutations in the protein CASK that have been shown to underlie pathologies ranging from X-linked mental retardation to autism spectrum disorder. A successful classification of the mutations as damaging was not consistently achieved despite the known pathogenicity. In addition to the bioinformatics analyses, we performed molecular modeling and phylogenetic comparisons. Finally, we developed a simple high-throughput imaging assay to measure the misfolding propensity of the CASK mutants in situ. Our data suggests that a phylogenetic analysis may be a robust method for predicting structurally damaging mutations in CASK. Mutations in two evolutionarily invariant residues (Y728C and W919R) exhibited a strong propensity to misfold and form visible aggregates in the cytosolic milieu. The remaining mutations (R28L, Y268H, and P396S) showed no evidence of aggregation and maintained their interactions with known CASK binding partners liprin-α3 Mint-1, and Veli, indicating an intact structure. Intriguingly, the protein aggregation caused by the Y728C and W919R mutations was reversed by treating the cells with a chemical chaperone (glycerol), providing a possible therapeutic strategy for treating structural mutations in CASK in the future.
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Affiliation(s)
- Leslie E. W. LaConte
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia, United States of America
| | - Vrushali Chavan
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia, United States of America
| | - Konark Mukherjee
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia, United States of America
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
- * E-mail:
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