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Yu K, Liu X, Yang B. The correlation between deafness progression and SLC26A4 mutations in enlarged vestibular aqueduct patients. Eur Arch Otorhinolaryngol 2024; 281:649-654. [PMID: 37477685 DOI: 10.1007/s00405-023-08123-5] [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: 05/02/2023] [Accepted: 07/04/2023] [Indexed: 07/22/2023]
Abstract
BACKGROUND The relationship between the hearing phenotype and the SLC26A4 mutation in enlarged vestibular aqueduct cases has not been fully elucidated. OBJECTIVES To detect SLC26A4 mutation in a group of cases with enlarged vestibular aqueduct who received cochlear implantation and to analyze the correlation between the SLC26A4 genotype and the progression of deafness. MATERIALS AND METHODS Twenty-nine enlarged vestibular aqueduct patients were selected. Using the Sanger sequence to analyze SLC26A4 gene mutations. The 29 cases were divided into group A (carrying the c.919-2A > G mutation) and group B (not carrying the c.919-2A > G mutation). The difference in the duration of deafness was analyzed between the two groups. RESULTS The detection rate of the c.1174A > T mutation in the postlingual deafness group was 37.5%, higher than that in the prelingual deafness group (0%). The difference in the duration of deafness between groups A and B was not statistically significant by the Mann-Whitney U test (p > 0.05). CONCLUSIONS The correlation between the SLC26A4 genotype and the duration of deafness in cases with enlarged vestibular aqueduct is not yet clear. However, the c.1174A > T mutation may be linked to delayed hearing loss and the progression of deafness may be relatively slow in some cases of c.919-2A > G mutation.
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Affiliation(s)
- Kejia Yu
- The Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, China
| | - Xiao Liu
- Department of Otorhinolaryngology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Beibei Yang
- Department of Otorhinolaryngology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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2
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Li L, Shen T, Liu S, Qi J, Zhao Y. Advancements and future prospects of adeno-associated virus-mediated gene therapy for sensorineural hearing loss. Front Neurosci 2024; 18:1272786. [PMID: 38327848 PMCID: PMC10847333 DOI: 10.3389/fnins.2024.1272786] [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] [Received: 08/04/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024] Open
Abstract
Sensorineural hearing loss (SNHL), a highly prevalent sensory impairment, results from a multifaceted interaction of genetic and environmental factors. As we continually gain insights into the molecular basis of auditory development and the growing compendium of deafness genes identified, research on gene therapy for SNHL has significantly deepened. Adeno-associated virus (AAV), considered a relatively secure vector for gene therapy in clinical trials, can deliver various transgenes based on gene therapy strategies such as gene replacement, gene silencing, gene editing, or gene addition to alleviate diverse types of SNHL. This review delved into the preclinical advances in AAV-based gene therapy for SNHL, spanning hereditary and acquired types. Particular focus is placed on the dual-AAV construction method and its application, the vector delivery route of mouse inner ear models (local, systemic, fetal, and cerebrospinal fluid administration), and the significant considerations in transforming from AAV-based animal model inner ear gene therapy to clinical implementation.
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Affiliation(s)
- Linke Li
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Tian Shen
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Shixi Liu
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Jieyu Qi
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Yu Zhao
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
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3
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Geertsma ER, Oliver D. SLC26 Anion Transporters. Handb Exp Pharmacol 2024; 283:319-360. [PMID: 37947907 DOI: 10.1007/164_2023_698] [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] [Indexed: 11/12/2023]
Abstract
Solute carrier family 26 (SLC26) is a family of functionally diverse anion transporters found in all kingdoms of life. Anions transported by SLC26 proteins include chloride, bicarbonate, and sulfate, but also small organic dicarboxylates such as fumarate and oxalate. The human genome encodes ten functional homologs, several of which are causally associated with severe human diseases, highlighting their physiological importance. Here, we review novel insights into the structure and function of SLC26 proteins and summarize the physiological relevance of human members.
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Affiliation(s)
- Eric R Geertsma
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
| | - Dominik Oliver
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, Marburg, Germany.
- Center for Mind, Brain and Behavior (CMBB), Universities of Marburg and Giessen, Marburg, Giessen, Germany.
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4
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Jung J, Noh SH, Jo S, Song D, Kang MJ, Shin MH, Lee HJ, Pyun JC, Namkung W, Han G, Lee MG, Choi JY. Novel small molecule-mediated restoration of the surface expression and anion exchange activity of mutated pendrin causing Pendred syndrome and DFNB4. Biomed Pharmacother 2023; 167:115445. [PMID: 37690388 DOI: 10.1016/j.biopha.2023.115445] [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: 07/07/2023] [Revised: 08/28/2023] [Accepted: 09/04/2023] [Indexed: 09/12/2023] Open
Abstract
Variants in SLC26A4 (pendrin) are the most common reasons for genetic hearing loss and vestibular dysfunction in East Asians. In patients with Pendred syndrome and DFNB4 (autosomal recessive type of genetic hearing loss 4), caused by variants in SLC26A4, the hearing function is residual at birth and deteriorates over several years, with no curative treatment for these disorders. In the present study, we revealed that a novel small molecule restores the expression and function of mutant pendrin. High-throughput screening of 54,000 small molecules was performed. We observed that pendrin corrector (PC2-1) increased the surface expression and anion exchange activity of p.H723R pendrin (H723R-PDS), the most prevalent genetic variant that causes Pendred syndrome and DFNB4. Furthermore, in endogenous H723R-PDS-expressing human nasal epithelial cells, PC2-1 significantly increased the surface expression of pendrin. PC2-1 exhibited high membrane permeability in vitro and high micromolar concentrations in the cochlear perilymph in vivo. In addition, neither inhibition of Kv11.1 activity in the human ether-a-go-go-related gene assay nor cell toxicity in the cell proliferation assay was observed at a high PC2-1 concentration (30 μM). These preclinical data support the hypothesis of the druggability of mutant pendrin using the novel corrector molecule PC2-1. In conclusion, PC2-1 may be a new therapeutic molecule for ameliorating hearing loss and treating vestibular disorders in patients with Pendred syndrome or DFNB4.
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Affiliation(s)
- Jinsei Jung
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul 03722, Republic of Korea; Won-Sang Lee Institute for Hearing Loss, Seoul 03722, Republic of Korea
| | - Shin Hye Noh
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Sungwoo Jo
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea
| | - Doona Song
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea; Department of Integrated OMICS for Biomedical Science, Yonsei University, Seoul 03722, Republic of Korea; Translational Research Center for Protein Function Control, Department of Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Min Jin Kang
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul 03722, Republic of Korea; Won-Sang Lee Institute for Hearing Loss, Seoul 03722, Republic of Korea
| | - Mi Hwa Shin
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul 03722, Republic of Korea; Won-Sang Lee Institute for Hearing Loss, Seoul 03722, Republic of Korea
| | - Hyun Jae Lee
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, USA
| | - Jae-Chul Pyun
- Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Wan Namkung
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea.
| | - Gyoonhee Han
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea; Department of Integrated OMICS for Biomedical Science, Yonsei University, Seoul 03722, Republic of Korea; Translational Research Center for Protein Function Control, Department of Biotechnology, Yonsei University, Seoul 03722, Republic of Korea.
| | - Min Goo Lee
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 03722, Republic of Korea; Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Republic of Korea, Seoul 03722, Republic of Korea.
| | - Jae Young Choi
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul 03722, Republic of Korea; Won-Sang Lee Institute for Hearing Loss, Seoul 03722, Republic of Korea.
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5
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Petit C, Bonnet C, Safieddine S. Deafness: from genetic architecture to gene therapy. Nat Rev Genet 2023; 24:665-686. [PMID: 37173518 DOI: 10.1038/s41576-023-00597-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2023] [Indexed: 05/15/2023]
Abstract
Progress in deciphering the genetic architecture of human sensorineural hearing impairment (SNHI) or loss, and multidisciplinary studies of mouse models, have led to the elucidation of the molecular mechanisms underlying auditory system function, primarily in the cochlea, the mammalian hearing organ. These studies have provided unparalleled insights into the pathophysiological processes involved in SNHI, paving the way for the development of inner-ear gene therapy based on gene replacement, gene augmentation or gene editing. The application of these approaches in preclinical studies over the past decade has highlighted key translational opportunities and challenges for achieving effective, safe and sustained inner-ear gene therapy to prevent or cure monogenic forms of SNHI and associated balance disorders.
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Affiliation(s)
- Christine Petit
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012, Paris, France.
- Collège de France, F-75005, Paris, France.
| | - Crystel Bonnet
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012, Paris, France
| | - Saaïd Safieddine
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012, Paris, France
- Centre National de la Recherche Scientifique, F-75016, Paris, France
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6
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Danilchenko VY, Zytsar MV, Maslova EA, Orishchenko KE, Posukh OL. Insight into the Natural History of Pathogenic Variant c.919-2A>G in the SLC26A4 Gene Involved in Hearing Loss: The Evidence for Its Common Origin in Southern Siberia (Russia). Genes (Basel) 2023; 14:genes14040928. [PMID: 37107686 PMCID: PMC10137394 DOI: 10.3390/genes14040928] [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: 03/19/2023] [Revised: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Pathogenic variants in the SLC26A4 gene leading to nonsyndromic recessive deafness (DFNB4), or Pendred syndrome, are some of the most common causes of hearing loss worldwide. Earlier, we found a high proportion of SLC26A4-related hearing loss with prevailing pathogenic variant c.919-2A>G (69.3% among all mutated SLC26A4 alleles that have been identified) in Tuvinian patients belonging to the indigenous Turkic-speaking Siberian people living in the Tyva Republic (Southern Siberia, Russia), which implies a founder effect in the accumulation of c.919-2A>G in Tuvinians. To evaluate a possible common origin of c.919-2A>G, we genotyped polymorphic STR and SNP markers, intragenic and flanking SLC26A4, in patients homozygous for c.919-2A>G and in healthy controls. The common STR and SNP haplotypes carrying c.919-2A>G were revealed, which convincingly indicates the origin of c.919-2A>G from a single ancestor, supporting a crucial role of the founder effect in the c.919-2A>G prevalence in Tuvinians. Comparison analysis with previously published data revealed the identity of the small SNP haplotype (~4.5 kb) in Tuvinian and Han Chinese carriers of c.919-2A>G, which suggests their common origin from founder chromosomes. We assume that c.919-2A>G could have originated in the geographically close territories of China or Tuva and subsequently spread to other regions of Asia. In addition, the time intervals of the c.919-2A>G occurrence in Tuvinians were roughly estimated.
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Affiliation(s)
- Valeriia Yu Danilchenko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Marina V Zytsar
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Ekaterina A Maslova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Konstantin E Orishchenko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Olga L Posukh
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
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7
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Bałdyga N, Oziębło D, Gan N, Furmanek M, Leja ML, Skarżyński H, Ołdak M. The Genetic Background of Hearing Loss in Patients with EVA and Cochlear Malformation. Genes (Basel) 2023; 14:genes14020335. [PMID: 36833263 PMCID: PMC9957411 DOI: 10.3390/genes14020335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 01/31/2023] Open
Abstract
The most frequently observed congenital inner ear malformation is enlarged vestibular aqueduct (EVA). It is often accompanied with incomplete partition type 2 (IP2) of the cochlea and a dilated vestibule, which together constitute Mondini malformation. Pathogenic SLC26A4 variants are considered the major cause of inner ear malformation but the genetics still needs clarification. The aim of this study was to identify the cause of EVA in patients with hearing loss (HL). Genomic DNA was isolated from HL patients with radiologically confirmed bilateral EVA (n = 23) and analyzed by next generation sequencing using a custom HL gene panel encompassing 237 HL-related genes or a clinical exome. The presence and segregation of selected variants and the CEVA haplotype (in the 5' region of SLC26A4) was verified by Sanger sequencing. Minigene assay was used to evaluate the impact of novel synonymous variant on splicing. Genetic testing identified the cause of EVA in 17/23 individuals (74%). Two pathogenic variants in the SLC26A4 gene were identified as the cause of EVA in 8 of them (35%), and a CEVA haplotype was regarded as the cause of EVA in 6 of 7 patients (86%) who carried only one SLC26A4 genetic variant. In two individuals with a phenotype matching branchio-oto-renal (BOR) spectrum disorder, cochlear hypoplasia resulted from EYA1 pathogenic variants. In one patient, a novel variant in CHD7 was detected. Our study shows that SLC26A4, together with the CEVA haplotype, accounts for more than half of EVA cases. Syndromic forms of HL should also be considered in patients with EVA. We conclude that to better understand inner ear development and the pathogenesis of its malformations, there is a need to look for pathogenic variants in noncoding regions of known HL genes or to link them with novel candidate HL genes.
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Affiliation(s)
- Natalia Bałdyga
- Department of Genetics, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
- Doctoral School of Translational Medicine, Medical Centre of Postgraduate Education, 01-813 Warsaw, Poland
| | - Dominika Oziębło
- Department of Genetics, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
| | - Nina Gan
- Department of Genetics, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
- Doctoral School of Translational Medicine, Medical Centre of Postgraduate Education, 01-813 Warsaw, Poland
| | - Mariusz Furmanek
- Bioimaging Research Center, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
| | - Marcin L. Leja
- Department of Genetics, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
| | - Henryk Skarżyński
- Oto-Rhino-Laryngology Surgery Clinic, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
| | - Monika Ołdak
- Department of Genetics, Institute of Physiology and Pathology of Hearing, 02-042 Warsaw, Poland
- Correspondence: ; Tel.: +48-22-356-03-66
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8
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The Frequency of Common Deafness-Associated Variants Among 3,555,336 Newborns in China and 141,456 Individuals Across Seven Populations Worldwide. Ear Hear 2023; 44:232-241. [PMID: 36149380 DOI: 10.1097/aud.0000000000001274] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Genetic screening can benefit early detection and intervention for hearing loss. The frequency of common deafness-associated variants in general populations is highly important for genetic screening and genetic counseling tailored to different ethnic backgrounds. We aimed to analyze the frequency of common deafness-associated variants in a large population-based Chinese newborn cohort and to explore the population-specific features in diverse populations worldwide. DESIGN This population-based cohort study analyzed the frequency of common deafness-associated variants in 3,555,336 newborns in the Chinese Newborn Concurrent Hearing and Genetic Screening cohort. Participants were newborn infants born between January 2007 and September 2020. Limited genetic screening for 20 variants in 4 common deafness-associated genes and newborn hearing screening were offered concurrently to all newborns in the Chinese Newborn Concurrent Hearing and Genetic Screening cohort. Sequence information of 141,456 individuals was also analyzed from seven ethnic populations from the Genome Aggregation Database for 20 common deafness-related variants. Statistical analysis was performed using R. RESULTS A total of 3,555,326 Chinese neonates completed the Newborn Concurrent Hearing and Genetic Screening were included for analysis. We reported the distinct landscape of common deafness-associated variants in this large population-based cohort. We found that the carrier frequencies of GJB2 , SLC26A4 , GJB3 , and MT-RNR were 2.53%, 2.05%, 0.37%, and 0.25%, respectively. Furthermore, GJB2 c.235delC was the most common variant with an allele frequency of 0.99% in the Chinese newborn population. We also demonstrated nine East-Asia-enriched variants, one Ashkenazi Jewish-enriched variant, and one European/American-enriched variant for hearing loss. CONCLUSIONS We showed the distinct landscape of common deafness-associated variants in the Chinese newborn population and provided insights into population-specific features in diverse populations. These data can serve as a powerful resource for otolaryngologists and clinical geneticists to inform population-adjusted genetic screening programs for hearing loss.
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Tawalbeh M, Aburizeg D, Abu Alragheb BO, Alaqrabawi WS, Dardas Z, Srour L, Altarayra BH, Zayed AA, El Omari Z, Azab B. SLC26A4 Phenotypic Variability Influences Intra- and Inter-Familial Diagnosis and Management. Genes (Basel) 2022; 13:genes13122192. [PMID: 36553459 PMCID: PMC9778369 DOI: 10.3390/genes13122192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/01/2022] [Accepted: 11/17/2022] [Indexed: 11/25/2022] Open
Abstract
SLC26A4 is one of the most common genes causing autosomal recessive non-syndromic sensorineural hearing loss (SNHL). It has been reported to cause Pendred Syndrome (PDS) and DFNB4 which is deafness with enlarged vestibular aqueduct (EVA). However, mutated SLC26A4 is not conclusive for having either DFNB4 or PDS. Three unrelated Jordanian families consisting of eight affected individuals with congenital bilateral hearing loss (HL) participated in this study. Whole-exome and Sanger sequencing were performed to investigate the underlying molecular etiology of HL. Further clinical investigations, including laboratory blood workup for the thyroid gland, CT scan for the temporal bone, and thyroid ultrasound were performed. Three disease-causing variants were identified in SLC26A4 in the three families, two of which were novel. Two families had a novel pathogenic homozygous splice-site accepter variant (c.165-1G>C), while the third family had compound heterozygous pathogenic variants (c.1446G>A; p.Trp482* and c.304G>A; p.Gly102Arg). Our approach helped in redirecting the diagnosis of several affected members of three different families from non-syndromic HL to syndromic HL. Two of the affected individuals had typical PDS, one had DFNB4, while the rest had atypical PDS. Our work emphasized the intra- and inter-familial variability of SLC26A4-related phenotypes. In addition, we highlighted the variable phenotypic impact of SLC26A4 on tailoring a personalized healthcare management.
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Affiliation(s)
- Mohamed Tawalbeh
- Department of Special Surgery, Jordan University Hospital, Amman 11942, Jordan
- Correspondence: (M.T.); (B.A.)
| | - Dunia Aburizeg
- Department of Pathology and Microbiology and Forensic Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Bayan O. Abu Alragheb
- Department of Pathology and Microbiology and Forensic Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Wala Sami Alaqrabawi
- Hearing and Speech Department, School of Rehabilitation Sciences, The University of Jordan, Amman 11942, Jordan
- Audiology Department, Faculty of Medical Sciences, Hacettepe University, Ankara 06100, Turkey
| | - Zain Dardas
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Luma Srour
- Department of Pathology and Microbiology and Forensic Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | | | - Ayman A. Zayed
- Division of Endocrinology, Diabetes & Metabolism, Department of Internal Medicine, Jordan University Hospital, Amman 11942, Jordan
| | - Zaid El Omari
- Otolaryngology, Head and Neck Surgery Department, Jordanian Royal Medical Services, Amman 11855, Jordan
| | - Bilal Azab
- Department of Pathology and Microbiology and Forensic Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032, USA
- Correspondence: (M.T.); (B.A.)
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10
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Danilchenko VY, Zytsar MV, Maslova EA, Posukh OL. Selection of Diagnostically Significant Regions of the SLC26A4 Gene Involved in Hearing Loss. Int J Mol Sci 2022; 23:ijms232113453. [PMID: 36362242 PMCID: PMC9655724 DOI: 10.3390/ijms232113453] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/23/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Screening pathogenic variants in the SLC26A4 gene is an important part of molecular genetic testing for hearing loss (HL) since they are one of the common causes of hereditary HL in many populations. However, a large size of the SLC26A4 gene (20 coding exons) predetermines the difficulties of its complete mutational analysis, especially in large samples of patients. In addition, the regional or ethno-specific prevalence of SLC26A4 pathogenic variants has not yet been fully elucidated, except variants c.919-2A>G and c.2168A>G (p.His723Arg), which have been proven to be most common in Asian populations. We explored the distribution of currently known pathogenic and likely pathogenic (PLP) variants across the SLC26A4 gene sequence presented in the Deafness Variation Database for the selection of potential diagnostically important parts of this gene. As a result of this bioinformatic analysis, we found that molecular testing ten SLC26A4 exons (4, 6, 10, 11, 13−17 and 19) with flanking intronic regions can provide a diagnostic rate of 61.9% for all PLP variants in the SLC26A4 gene. The primary sequencing of these SLC26A4 regions may be applied as an initial effective diagnostic testing in samples of patients of unknown ethnicity or as a subsequent step after the targeted testing of already-known ethno- or region-specific pathogenic SLC26A4 variants.
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Affiliation(s)
- Valeriia Yu. Danilchenko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Marina V. Zytsar
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Ekaterina A. Maslova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Olga L. Posukh
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Novosibirsk State University, 630090 Novosibirsk, Russia
- Correspondence:
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11
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Matulevičius A, Bernardinelli E, Brownstein Z, Roesch S, Avraham KB, Dossena S. Molecular Features of SLC26A4 Common Variant p.L117F. J Clin Med 2022; 11:jcm11195549. [PMID: 36233414 PMCID: PMC9570580 DOI: 10.3390/jcm11195549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/16/2022] Open
Abstract
The SLC26A4 gene, which encodes the anion exchanger pendrin, is involved in determining syndromic (Pendred syndrome) and non-syndromic (DFNB4) autosomal recessive hearing loss. SLC26A4 c.349C>T, p.L117F is a relatively common allele in the Ashkenazi Jewish community, where its minor allele frequency is increased compared to other populations. Although segregation and allelic data support the pathogenicity of this variant, former functional tests showed characteristics that were indistinguishable from those of the wild-type protein. Here, we applied a triad of cell-based assays, i.e., measurement of the ion transport activity by a fluorometric method, determination of the subcellular localization by confocal microscopy, and assessment of protein expression levels, to conclusively assign or exclude the pathogenicity of SLC26A4 p.L117F. This protein variant showed a moderate, but significant, reduction in ion transport function, a partial retention in the endoplasmic reticulum, and a strong reduction in expression levels as a consequence of an accelerated degradation by the Ubiquitin Proteasome System, all supporting pathogenicity. The functional and molecular features of human pendrin p.L117F were recapitulated by the mouse ortholog, thus indicating that a mouse carrying this variant might represent a good model of Pendred syndrome/DFNB4.
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Affiliation(s)
- Arnoldas Matulevičius
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Emanuele Bernardinelli
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Zippora Brownstein
- Department of Human Molecular Genetics & Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Sebastian Roesch
- Department of Otorhinolaryngology, Head and Neck Surgery, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Karen B. Avraham
- Department of Human Molecular Genetics & Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
- Correspondence: (K.B.A.); (S.D.); Tel.: +972-3-6407030 (K.B.A.); +43-662-2420-80560 (S.D.)
| | - Silvia Dossena
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, 5020 Salzburg, Austria
- Correspondence: (K.B.A.); (S.D.); Tel.: +972-3-6407030 (K.B.A.); +43-662-2420-80560 (S.D.)
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12
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Different Rates of the SLC26A4-Related Hearing Loss in Two Indigenous Peoples of Southern Siberia (Russia). Diagnostics (Basel) 2021; 11:diagnostics11122378. [PMID: 34943614 PMCID: PMC8699871 DOI: 10.3390/diagnostics11122378] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/13/2021] [Accepted: 12/13/2021] [Indexed: 12/14/2022] Open
Abstract
Hereditary hearing loss (HL) is known to be highly locus/allelic heterogeneous, and the prevalence of different HL forms significantly varies among populations worldwide. Investigation of region-specific landscapes of hereditary HL is important for local healthcare and medical genetic services. Mutations in the SLC26A4 gene leading to nonsyndromic recessive deafness (DFNB4) and Pendred syndrome are common genetic causes of hereditary HL, at least in some Asian populations. We present for the first time the results of a thorough analysis of the SLC26A4 gene by Sanger sequencing in the large cohorts of patients with HL of unknown etiology belonging to two neighboring indigenous Turkic-speaking Siberian peoples (Tuvinians and Altaians). A definite genetic diagnosis based on the presence of biallelic SLC26A4 mutations was established for 28.2% (62/220) of all enrolled Tuvinian patients vs. 4.3% (4/93) of Altaian patients. The rate of the SLC26A4-related HL in Tuvinian patients appeared to be one of the highest among populations worldwide. The SLC26A4 mutational spectrum was characterized by the presence of Asian-specific mutations c.919-2A>G and c.2027T>A (p.Leu676Gln), predominantly found in Tuvinian patients, and c.2168A>G (p.His723Arg), which was only detected in Altaian patients. In addition, a novel pathogenic variant c.1545T>G (p.Phe515Leu) was found with high frequency in Tuvinian patients. Overall, based on the findings of this study and our previous research, we were able to uncover the genetic causes of HL in 50.5% of Tuvinian patients and 34.5% of Altaian patients.
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13
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Hu CJ, Lu YC, Tsai CY, Chan YH, Lin PH, Lee YS, Yu IS, Lin SW, Liu TC, Hsu CJ, Yang TH, Cheng YF, Wu CC. Insights into phenotypic differences between humans and mice with p.T721M and other C-terminal variants of the SLC26A4 gene. Sci Rep 2021; 11:20983. [PMID: 34697379 PMCID: PMC8545921 DOI: 10.1038/s41598-021-00448-7] [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: 06/01/2021] [Accepted: 09/22/2021] [Indexed: 11/17/2022] Open
Abstract
Recessive variants of the SLC26A4 gene are an important cause of hereditary hearing impairment. Several transgenic mice with different Slc26a4 variants have been generated. However, none have recapitulated the auditory phenotypes in humans. Of the SLC26A4 variants identified thus far, the p.T721M variant is of interest, as it appears to confer a more severe pathogenicity than most of the other missense variants, but milder pathogenicity than non-sense and frameshift variants. Using a genotype-driven approach, we established a knock-in mouse model homozygous for p.T721M. To verify the pathogenicity of p.T721M, we generated mice with compound heterozygous variants by intercrossing Slc26a4+/T721M mice with Slc26a4919-2A>G/919-2A>G mice, which segregated the c.919-2A > G variant with abolished Slc26a4 function. We then performed serial audiological assessments, vestibular evaluations, and inner ear morphological studies. Surprisingly, both Slc26a4T721M/T721M and Slc26a4919-2A>G/T721M showed normal audiovestibular functions and inner ear morphology, indicating that p.T721M is non-pathogenic in mice and a single p.T721M allele is sufficient to maintain normal inner ear physiology. The evidence together with previous reports on mouse models with Slc26a4 p.C565Y and p.H723R variants, support our speculation that the absence of audiovestibular phenotypes in these mouse models could be attributed to different protein structures at the C-terminus of human and mouse pendrin.
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Affiliation(s)
- Chin-Ju Hu
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan.,Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, MA, 02115, USA
| | - Ying-Chang Lu
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan
| | - Cheng-Yu Tsai
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan
| | - Yen-Hui Chan
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan.,Department of Otolaryngology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, 427, Taiwan
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan
| | - Yi-Shan Lee
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan
| | - I-Shing Yu
- Transgenic Mouse Models Core (TMMC), Division of Genomic Medicine, Research Center for Medical Excellence, National Taiwan University, Taipei, 100, Taiwan
| | - Shu-Wha Lin
- Transgenic Mouse Models Core (TMMC), Division of Genomic Medicine, Research Center for Medical Excellence, National Taiwan University, Taipei, 100, Taiwan
| | - Tien-Chen Liu
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan.,Department of Otolaryngology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Chuan-Jen Hsu
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan.,Department of Otolaryngology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, 427, Taiwan
| | - Ting-Hua Yang
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan.
| | - Yen-Fu Cheng
- Department of Medical Research, Taipei Veteran General Hospital, 201, Sec.2, Shi-Pai Rd, Taipei, 112, Taiwan. .,Department of Otolaryngology-Head and Neck Surgery, Taipei Veteran General Hospital, Taipei, 112, Taiwan. .,School of Medicine, National Yang Ming Chiao Tung University, Taipei, 112, Taiwan.
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, 7 Chung-Shan S. Rd., Taipei, 100, Taiwan. .,Department of Otolaryngology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan. .,Department of Medical Research, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, 302, Taiwan.
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14
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Yoshimura H, Nishio S, Usami S. Milestones toward cochlear gene therapy for patients with hereditary hearing loss. Laryngoscope Investig Otolaryngol 2021; 6:958-967. [PMID: 34693000 PMCID: PMC8513455 DOI: 10.1002/lio2.633] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/30/2021] [Accepted: 07/28/2021] [Indexed: 02/05/2023] Open
Abstract
A number of genes are reportedly responsible for hereditary hearing loss, which accounts for over 50% of all congenital hearing loss cases. Recent advances in genetic testing have enabled the identification of pathogenic variants in many cases, and systems have been developed to provide personalized treatment based on etiology. Gene therapy is expected to become an unprecedented curative treatment. Several reports have demonstrated the successful use of cochlear gene therapy to restore auditory function in mouse models of genetic deafness; however, many hurdles remain to its clinical application in humans. Herein, we focus on the frequency of deafness genes in patients with congenital and late-onset progressive hearing loss and discuss the following points regarding which genes need to be targeted to efficiently proceed with clinical application: (a) which cells' genes are expressed within the cochlea, (b) whether gene transfer to the targeted cells is possible using vectors such as adeno-associated virus, (c) what phenotype of hearing loss in patients is exhibited, and (d) whether mouse models exist to verify the effectiveness of treatment. Moreover, at the start of clinical application, gene therapy in combination with cochlear implantation may be useful for cases of progressive hearing loss.
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Affiliation(s)
- Hidekane Yoshimura
- Department of OtorhinolaryngologyShinshu University School of MedicineMatsumotoNaganoJapan
| | - Shin‐Ya Nishio
- Department of Hearing Implant SciencesShinshu University School of MedicineMatsumotoNaganoJapan
| | - Shin‐Ichi Usami
- Department of Hearing Implant SciencesShinshu University School of MedicineMatsumotoNaganoJapan
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15
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Roesch S, Rasp G, Sarikas A, Dossena S. Genetic Determinants of Non-Syndromic Enlarged Vestibular Aqueduct: A Review. Audiol Res 2021; 11:423-442. [PMID: 34562878 PMCID: PMC8482117 DOI: 10.3390/audiolres11030040] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/02/2021] [Accepted: 08/24/2021] [Indexed: 12/13/2022] Open
Abstract
Hearing loss is the most common sensorial deficit in humans and one of the most common birth defects. In developed countries, at least 60% of cases of hearing loss are of genetic origin and may arise from pathogenic sequence alterations in one of more than 300 genes known to be involved in the hearing function. Hearing loss of genetic origin is frequently associated with inner ear malformations; of these, the most commonly detected is the enlarged vestibular aqueduct (EVA). EVA may be associated to other cochleovestibular malformations, such as cochlear incomplete partitions, and can be found in syndromic as well as non-syndromic forms of hearing loss. Genes that have been linked to non-syndromic EVA are SLC26A4, GJB2, FOXI1, KCNJ10, and POU3F4. SLC26A4 and FOXI1 are also involved in determining syndromic forms of hearing loss with EVA, which are Pendred syndrome and distal renal tubular acidosis with deafness, respectively. In Caucasian cohorts, approximately 50% of cases of non-syndromic EVA are linked to SLC26A4 and a large fraction of patients remain undiagnosed, thus providing a strong imperative to further explore the etiology of this condition.
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Affiliation(s)
- Sebastian Roesch
- Department of Otorhinolaryngology, Head and Neck Surgery, Paracelsus Medical University, 5020 Salzburg, Austria; (S.R.); (G.R.)
| | - Gerd Rasp
- Department of Otorhinolaryngology, Head and Neck Surgery, Paracelsus Medical University, 5020 Salzburg, Austria; (S.R.); (G.R.)
| | - Antonio Sarikas
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, 5020 Salzburg, Austria;
| | - Silvia Dossena
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, 5020 Salzburg, Austria;
- Correspondence: ; Tel.: +43-(0)662-2420-80564
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16
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Smits JJ, de Bruijn SE, Lanting CP, Oostrik J, O'Gorman L, Mantere T, Cremers FPM, Roosing S, Yntema HG, de Vrieze E, Derks R, Hoischen A, Pegge SAH, Neveling K, Pennings RJE, Kremer H. Exploring the missing heritability in subjects with hearing loss, enlarged vestibular aqueducts, and a single or no pathogenic SLC26A4 variant. Hum Genet 2021; 141:465-484. [PMID: 34410491 PMCID: PMC9035008 DOI: 10.1007/s00439-021-02336-6] [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: 05/30/2021] [Accepted: 08/09/2021] [Indexed: 12/11/2022]
Abstract
Pathogenic variants in SLC26A4 have been associated with autosomal recessive hearing loss (arHL) and a unilateral or bilateral enlarged vestibular aqueduct (EVA). SLC26A4 is the second most frequently mutated gene in arHL. Despite the strong genotype–phenotype correlation, a significant part of cases remains genetically unresolved. In this study, we investigated a cohort of 28 Dutch index cases diagnosed with HL in combination with an EVA but without (M0) or with a single (M1) pathogenic variant in SLC26A4. To explore the missing heritability, we first determined the presence of the previously described EVA-associated haplotype (Caucasian EVA (CEVA)), characterized by 12 single nucleotide variants located upstream of SLC26A4. We found this haplotype and a delimited V1-CEVA haplotype to be significantly enriched in our M1 patient cohort (10/16 cases). The CEVA haplotype was also present in two M0 cases (2/12). Short- and long-read whole genome sequencing and optical genome mapping could not prioritize any of the variants present within the CEVA haplotype as the likely pathogenic defect. Short-read whole-genome sequencing of the six M1 cases without this haplotype and the two M0/CEVA cases only revealed previously overlooked or misinterpreted splice-altering SLC26A4 variants in two cases, who are now genetically explained. No deep-intronic or structural variants were identified in any of the M1 subjects. With this study, we have provided important insights that will pave the way for elucidating the missing heritability in M0 and M1 SLC26A4 cases. For pinpointing the pathogenic effect of the CEVA haplotype, additional analyses are required addressing defect(s) at the RNA, protein, or epigenetic level.
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Affiliation(s)
- Jeroen J Smits
- Hearing and Genes, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Suzanne E de Bruijn
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Cornelis P Lanting
- Hearing and Genes, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jaap Oostrik
- Hearing and Genes, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Luke O'Gorman
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Tuomo Mantere
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Laboratory of Cancer Genetics and Tumor Biology, Cancer and Translational Medicine Research Unit and Biocenter Oulu, University of Oulu, Oulu, Finland
| | | | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Susanne Roosing
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Helger G Yntema
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Erik de Vrieze
- Hearing and Genes, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ronny Derks
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Alexander Hoischen
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Center for Infectious Diseases (RCI), Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.,Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Radboud Expertise Center for Immunodeficiency and Autoinflammation and Center for Infectious Disease (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sjoert A H Pegge
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Kornelia Neveling
- Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Ronald J E Pennings
- Hearing and Genes, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hannie Kremer
- Hearing and Genes, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands. .,Department of Human Genetics, Radboud University Medical Center, Internal Postal Code 855, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands. .,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
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17
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Honda K, Griffith AJ. Genetic architecture and phenotypic landscape of SLC26A4-related hearing loss. Hum Genet 2021; 141:455-464. [PMID: 34345941 DOI: 10.1007/s00439-021-02311-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 06/29/2021] [Indexed: 12/15/2022]
Abstract
Mutations of coding regions and splice sites of SLC26A4 cause Pendred syndrome and nonsyndromic recessive hearing loss DFNB4. SLC26A4 encodes pendrin, a transmembrane exchanger of anions and bases. The mutant SLC26A4 phenotype is characterized by inner ear malformations, including an enlarged vestibular aqueduct (EVA), incomplete cochlear partition type II and modiolar hypoplasia, progressive and fluctuating hearing loss, and vestibular dysfunction. A thyroid iodine organification defect can lead to multinodular goiter and distinguishes Pendred syndrome from DFNB4. Pendred syndrome and DFNB4 are each inherited as an autosomal recessive trait caused by biallelic mutations of SLC26A4 (M2). However, there are some EVA patients with only one detectable mutant allele (M1) of SLC26A4. In most European-Caucasian M1 patients, there is a haplotype that consists of 12 variants upstream of SLC26A4, called CEVA (Caucasian EVA), which acts as a pathogenic recessive allele in trans to mutations affecting the coding regions or splice sites of SLC26A4. This combination of an M1 genotype with the CEVA haplotype is associated with a less severe phenotype than the M2 genotype. The phenotype in EVA patients with no mutant alleles of SLC26A4 (M0) has a very low recurrence probability and is likely to be caused by other factors.
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Affiliation(s)
- Keiji Honda
- Department of Otorhinolaryngology, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, Japan
| | - Andrew J Griffith
- Department of Otolaryngology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA.
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18
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Slavney AJ, Kawakami T, Jensen MK, Nelson TC, Sams AJ, Boyko AR. Five genetic variants explain over 70% of hair coat pheomelanin intensity variation in purebred and mixed breed domestic dogs. PLoS One 2021; 16:e0250579. [PMID: 34043658 PMCID: PMC8158882 DOI: 10.1371/journal.pone.0250579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 04/08/2021] [Indexed: 11/19/2022] Open
Abstract
In mammals, the pigment molecule pheomelanin confers red and yellow color to hair, and the intensity of this coloration is caused by variation in the amount of pheomelanin. Domestic dogs exhibit a wide range of pheomelanin intensity, ranging from the white coat of the Samoyed to the deep red coat of the Irish Setter. While several genetic variants have been associated with specific coat intensity phenotypes in certain dog breeds, they do not explain the majority of phenotypic variation across breeds. In order to gain further insight into the extent of multigenicity and epistatic interactions underlying coat pheomelanin intensity in dogs, we leveraged a large dataset obtained via a direct-to-consumer canine genetic testing service. This consisted of genome-wide single nucleotide polymorphism (SNP) genotype data and owner-provided photos for 3,057 pheomelanic mixed breed and purebred dogs from 63 breeds and varieties spanning the full range of canine coat pheomelanin intensity. We first performed a genome-wide association study (GWAS) on 2,149 of these dogs to search for additional genetic variants that underlie intensity variation. GWAS identified five loci significantly associated with intensity, of which two (CFA15 29.8 Mb and CFA20 55.8 Mb) replicate previous findings and three (CFA2 74.7 Mb, CFA18 12.9 Mb, CFA21 10.9 Mb) have not previously been reported. In order to assess the combined predictive power of these loci across dog breeds, we used our GWAS data set to fit a linear model, which explained over 70% of variation in coat pheomelanin intensity in an independent validation dataset of 908 dogs. These results introduce three novel pheomelanin intensity loci, and further demonstrate the multigenic nature of coat pheomelanin intensity determination in domestic dogs.
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Affiliation(s)
- Andrea J. Slavney
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
| | - Takeshi Kawakami
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
| | - Meghan K. Jensen
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
| | - Thomas C. Nelson
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
| | - Aaron J. Sams
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
| | - Adam R. Boyko
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
- Department of Biomedical Sciences, Cornell University College of Veterinary Medicine, Ithaca, New York, United States of America
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19
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Mohri H, Ninoyu Y, Sakaguchi H, Hirano S, Saito N, Ueyama T. Nox3-Derived Superoxide in Cochleae Induces Sensorineural Hearing Loss. J Neurosci 2021; 41:4716-4731. [PMID: 33849947 PMCID: PMC8260246 DOI: 10.1523/jneurosci.2672-20.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 04/02/2021] [Accepted: 04/05/2021] [Indexed: 01/02/2023] Open
Abstract
Reactive oxygen species (ROS) produced by NADPH oxidases (Nox) contribute to the development of different types of sensorineural hearing loss (SNHL), a common impairment in humans with no established treatment. Although the essential role of Nox3 in otoconia biosynthesis and its possible involvement in hearing have been reported in rodents, immunohistological methods targeted at detecting Nox3 expression in inner ear cells reveal ambiguous results. Therefore, the mechanism underlying Nox3-dependent SNHL remains unclear and warrants further investigation. We generated Nox3-Cre knock-in mice, in which Nox3 was replaced with Cre recombinase (Cre). Using Nox3-Cre;tdTomato mice of either sex, in which tdTomato is expressed under the control of the Nox3 promoter, we determined Nox3-expressing regions and cell types in the inner ear. Nox3-expressing cells in the cochlea included various types of supporting cells, outer hair cells, inner hair cells, and spiral ganglion neurons. Nox3 expression increased with cisplatin, age, and noise insults. Moreover, increased Nox3 expression in supporting cells and outer hair cells, especially at the basal turn of the cochlea, played essential roles in ROS-related SNHL. The extent of Nox3 involvement in SNHL follows the following order: cisplatin-induced hearing loss > age-related hearing loss > noise-induced hearing loss. Here, on the basis of Nox3-Cre;tdTomato, which can be used as a reporter system (Nox3-Cre+/-;tdTomato+/+ and Nox3-Cre+/+;tdTomato+/+), and Nox3-KO (Nox3-Cre+/+;tdTomato+/+) mice, we demonstrate that Nox3 inhibition in the cochlea is a promising strategy for ROS-related SNHL, such as cisplatin-induced HL, age-related HL, and noise-induced HL.SIGNIFICANCE STATEMENT We found Nox3-expressing regions and cell types in the inner ear, especially in the cochlea, using Nox3-Cre;tdTomato mice, a reporter system generated in this study. Nox3 expression increased with cisplatin, age, and noise insults in specific cell types in the cochlea and resulted in the loss (apoptosis) of outer hair cells. Thus, Nox3 might serve as a molecular target for the development of therapeutics for sensorineural hearing loss, particularly cisplatin-induced, age-related, and noise-induced hearing loss.
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Affiliation(s)
- Hiroaki Mohri
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe, 657-8501, Japan
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yuzuru Ninoyu
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe, 657-8501, Japan
| | - Hirofumi Sakaguchi
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Shigeru Hirano
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Naoaki Saito
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe, 657-8501, Japan
| | - Takehiko Ueyama
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe, 657-8501, Japan
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20
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Absence of Endolymphatic Sac Ion Transport Proteins in Large Vestibular Aqueduct Syndrome-A Human Temporal Bone Study. Otol Neurotol 2021; 41:e1256-e1263. [PMID: 32890293 DOI: 10.1097/mao.0000000000002832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Epithelial ion transport pathologies of the endolymphatic sac (ES) are associated with large vestibular aqueduct syndrome (LVAS). BACKGROUND LVAS is defined by the pathognomonic features of a widened bony vestibular aqueduct (VA) and an enlarged ES. The underlying cause of its associated cochleovestibular symptoms remains elusive. Disturbances in epithelial ion transport in the enlarged ES, affecting inner ear fluid regulation, were proposed as a possible pathophysiology. However, although respective epithelial ion transport pathologies have been demonstrated in the enlarged ES from transgenic LVAS mouse models, these pathologies have not been investigated in human LVAS cases. METHODS Histological and immunohistochemical analysis of the enlarged ES epithelium in postmortem temporal bones from two individuals with a clinical diagnosis of LVAS. RESULTS The enlarged ES epithelium demonstrated an overall atypical epithelial differentiation and a lack of the immunolocalization of signature ion transport proteins. Notably, in both cases, a rudimentary branch of the ES with a typically differentiated ES epithelium was present. CONCLUSIONS The described cellular and molecular pathologies of the enlarged ES in humans provide evidence of epithelial transport pathology as one potential cause of cochleovestibular symptoms in LVAS. The present findings also emphasize the clinical relevance of already established LVAS mouse models.
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Hu CJ, Lu YC, Yang TH, Chan YH, Tsai CY, Yu IS, Lin SW, Liu TC, Cheng YF, Wu CC, Hsu CJ. Toward the Pathogenicity of the SLC26A4 p.C565Y Variant Using a Genetically Driven Mouse Model. Int J Mol Sci 2021; 22:2789. [PMID: 33801843 PMCID: PMC8001573 DOI: 10.3390/ijms22062789] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/05/2021] [Accepted: 03/05/2021] [Indexed: 11/19/2022] Open
Abstract
Recessive variants of the SLC26A4 gene are globally a common cause of hearing impairment. In the past, cell lines and transgenic mice were widely used to investigate the pathogenicity associated with SLC26A4 variants. However, discrepancies in pathogenicity between humans and cell lines or transgenic mice were documented for some SLC26A4 variants. For instance, the p.C565Y variant, which was reported to be pathogenic in humans, did not exhibit functional pathogenic consequences in cell lines. To address the pathogenicity of p.C565Y, we used a genotype-based approach in which we generated knock-in mice that were heterozygous (Slc26a4+/C565Y), homozygous (Slc26a4C565Y/C565Y), and compound heterozygous (Slc26a4919-2A>G/C565Y) for this variant. Subsequent phenotypic characterization revealed that mice with these genotypes demonstrated normal auditory and vestibular functions, and normal inner-ear morphology and pendrin expression. These findings indicate that the p.C565Y variant is nonpathogenic for mice, and that a single p.C565Y allele is sufficient to maintain normal inner-ear physiology in mice. Our results highlight the differences in pathogenicity associated with certain SLC26A4 variants between transgenic mice and humans, which should be considered when interpreting the results of animal studies for SLC26A4-related deafness.
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Affiliation(s)
- Chin-Ju Hu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, MA 02115, USA
| | - Ying-Chang Lu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
- Department of Medical Research, Taipei Veteran General Hospital, Taipei 112, Taiwan
| | - Ting-Hua Yang
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
| | - Yen-Hui Chan
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
- Department of Otolaryngology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung 427, Taiwan
| | - Cheng-Yu Tsai
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
| | - I-Shing Yu
- Transgenic Mouse Models Core (TMMC), Division of Genomic Medicine, Research Center for Medical Excellence, National Taiwan University, Taipei 100, Taiwan; (I-S.Y.); (S.-W.L.)
| | - Shu-Wha Lin
- Transgenic Mouse Models Core (TMMC), Division of Genomic Medicine, Research Center for Medical Excellence, National Taiwan University, Taipei 100, Taiwan; (I-S.Y.); (S.-W.L.)
| | - Tien-Chen Liu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
| | - Yen-Fu Cheng
- Department of Medical Research, Taipei Veteran General Hospital, Taipei 112, Taiwan
- Department of Otolaryngology-Head and Neck Surgery, Taipei Veteran General Hospital, Taipei 112, Taiwan
- Faculty of Medicine, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
- Institute of Brain Science, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 100, Taiwan
- Department of Otolaryngology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Chuan-Jen Hsu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-J.H.); (Y.-C.L.); (T.-H.Y.); (Y.-H.C.); (C.-Y.T.); (T.-C.L.); (C.-J.H.)
- Department of Otolaryngology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung 427, Taiwan
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Missense Variant of Endoplasmic Reticulum Region of WFS1 Gene Causes Autosomal Dominant Hearing Loss without Syndromic Phenotype. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6624744. [PMID: 34258273 PMCID: PMC8260318 DOI: 10.1155/2021/6624744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/01/2021] [Accepted: 02/14/2021] [Indexed: 12/13/2022]
Abstract
Objective Genetic variants in the WFS1 gene can cause Wolfram syndrome (WS) or autosomal dominant nonsyndromic low-frequency hearing loss (HL). This study is aimed at investigating the molecular basis of HL in an affected Chinese family and the genotype-phenotype correlation of WFS1 variants. Methods The clinical phenotype of the five-generation Chinese family was characterized using audiological examinations and pedigree analysis. Target exome sequencing of 129 known deafness genes and bioinformatics analysis were performed among six patients and four normal subjects to screen suspected pathogenic variants. We built a complete WFS1 protein model to assess the potential effects of the variant on protein structure. Results A novel heterozygous pathogenic variant NM_006005.3 c.2020G>T (p.Gly674Trp) was identified in the WFS1 gene, located in the C-terminal domain of the wolframin protein. We further showed that HL-related WFS1 missense variants were mainly concentrated in the endoplasmic reticulum (ER) domain. In contrast, WS-related missense variants are randomly distributed throughout the protein. Conclusions In this family, we identified a novel variant p.Gly674Trp of WFS1 as the primary pathogenic variant causing the low-frequency sensorineural HL, enriching the mutational spectrum of the WFS1 gene.
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Simon F, Denoyelle F, Beraneck M. Interpreting pendred syndrome as a foetal hydrops: Clinical and animal model evidence. J Vestib Res 2021; 31:315-321. [PMID: 33579884 DOI: 10.3233/ves-200789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Menière disease (MD) and SLC26A4 related deafness (Pendred syndrome (PS) or DFNB4) are two different inner ear disorders which present with fluctuating and progressive hearing loss, which could be a direct consequence of endolymphatic hydrops. OBJECTIVE To present similarities between both pathologies and explore how the concept of hydrops may be applied to PS/DFNB4. METHODS Review of the literature on MD, PS/DFNB4 and mouse model of PS/DFNB4. RESULTS MD and PS/DFNB4 share a number of similarities such as fluctuating and progressive hearing loss, acute episodes with vertigo and tinnitus, MRI and histological evidence of endolymphatic hydrops (although with different underlying mechanisms). MD is usually diagnosed during the fourth decade of life whereas PS/DFNB4 is congenital. The PS/DFNB4 mouse models have shown that biallelic slc26a4 mutations lead to Na+ and water retention in the endolymph during the perinatal period, which in turn induces degeneration of the stria vascularis and hearing loss. Crossing clinical/imagery characteristics and animal models, evidence seems to support the hypothesis of PS being a foetal hydrops. CONCLUSIONS When understanding PS/DFNB4 as a developmental hydrops, treatments used in MD could be repositioned to PS.
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Affiliation(s)
- François Simon
- Université de Paris, INCC UMR 8002, CNRS, F-75006 Paris, France.,Université de Paris, Faculté de Médecine, F-75006 Paris, France.,Department of Paediatric Otolaryngology, AP-HP, Hôpital Necker-Enfants Malades, F-75015 Paris, France
| | - Françoise Denoyelle
- Université de Paris, Faculté de Médecine, F-75006 Paris, France.,Department of Paediatric Otolaryngology, AP-HP, Hôpital Necker-Enfants Malades, F-75015 Paris, France
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牛 文, 许 慧, 秦 利, 王 广, 丁 韶, 谢 存, 贾 晓, 刘 宏. [Genotype and clinical phenotype analysis of 42 patients with delayed nonsyndromic hearing loss]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2021; 35:131-136. [PMID: 33540994 PMCID: PMC10127873 DOI: 10.13201/j.issn.2096-7993.2021.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Indexed: 06/12/2023]
Abstract
Objective:The aim of this study is to analyze the mutation characteristics of GJB2 and SLC26A4 gene in patients with delayed non-syndromic hearing loss, which is beneficial to the early detection and intervention of delayed deafness. Methods:Sanger sequencing technology was used to detect two common genes in 139 patients with non-syndromic deafness, six hot spot mutations in GJB2 gene and SLC26A4 gene, and single heterozygous mutations found in GJB2 gene and SLC26A4 gene were detected by whole exome sequencing. Results:Among the 25 patients with deafness caused by GJB2 gene mutation, 12 of them passed universal newborn hearing screening and then developed delayed extremely severe hearing loss. The onset time of hearing loss was 6-48 months. All the genotypes were homozygous or compound heterozygous mutation of c. 235delC, especially genotype of GJB2 c. 235delC homozygous and c. 235delC/c. 299-300 delAT compound heterozygous mutations, and the CT manifestations were normal. Among the 42 patients with deafness caused by SLC26A4 gene mutation, 30 of them passed universal newborn hearing screening and developed delayed deafness. The onset time of hearing loss was three months to ten years old. Among them, the genotypes of 21 patients were compound heterozygous mutation, and 9 patients were homozygous mutation of c. 919-2A>G, especially genotypes were SLC26A4 c. 919-2A>G/c. 665G>T and c. 919-2A>G /c. 2027T>A compound heterozygous mutation. The CT findings of 19 cases showed single enlarged vestibular aqueduct, and 11 cases showed enlarged vestibular aqueduct with Mondini malformation. Conclusion:For the children who have passed universal newborn hearing screening, the genotypes detected are GJB2 c. 235delC homozygous, SLC26A4 c. 919-2A>G homozygous or compound heterozygous mutations, especially genotypes GJB2 c. 235delC homozygous, c. 235delC/c. 299-300delAT compound heterozygous mutations and SLC26A4 c. 919-2A>G/c. 665G>T and c. 919-2A>G/c. 2027T>A compound heterozygous mutation. Attention should be paid to the hearing problems of children all the time, and the possibility of delayed deafness in the future should be considered.
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Affiliation(s)
- 文侠 牛
- 河南大学人民医院 河南省人民医院耳鼻咽喉头颈外科(郑州,450003)Department of Otolaryngology Head and Neck Surgery, Henan University People's Hospital, Henan Provincial People's Hospital, Zhengzhou, 450003, China
| | - 慧娟 许
- 河南大学人民医院 河南省人民医院耳鼻咽喉头颈外科(郑州,450003)Department of Otolaryngology Head and Neck Surgery, Henan University People's Hospital, Henan Provincial People's Hospital, Zhengzhou, 450003, China
| | - 利涛 秦
- 河南省人民医院 郑州大学人民医院 河南省医学遗传研究所Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Medical Genetics of Henan Provincial
| | - 广科 王
- 河南省人民医院 郑州大学人民医院 河南大学人民医院耳鼻咽喉头颈外科Department of Otolaryngology Head and Neck Surgery, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan University People's Hospital
| | - 韶洸 丁
- 河南省人民医院 郑州大学人民医院 河南大学人民医院耳鼻咽喉头颈外科Department of Otolaryngology Head and Neck Surgery, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan University People's Hospital
| | - 存存 谢
- 河南省人民医院 郑州大学人民医院 河南大学人民医院耳鼻咽喉头颈外科Department of Otolaryngology Head and Neck Surgery, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan University People's Hospital
| | - 晓东 贾
- 河南省人民医院 郑州大学人民医院 河南大学人民医院耳鼻咽喉头颈外科Department of Otolaryngology Head and Neck Surgery, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan University People's Hospital
| | - 宏建 刘
- 河南省人民医院 郑州大学人民医院 河南大学人民医院耳鼻咽喉头颈外科Department of Otolaryngology Head and Neck Surgery, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan University People's Hospital
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25
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Zhou K, Huang L, Feng M, Li X, Zhao Y, Liu F, Wei J, Qin D, Lu Q, Shi M, Qu S, Tang F. A novel SLC26A4 splicing mutation identified in two deaf Chinese twin sisters with enlarged vestibular aqueducts. Mol Genet Genomic Med 2020; 8:e1447. [PMID: 32770655 PMCID: PMC7549568 DOI: 10.1002/mgg3.1447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 12/13/2022] Open
Abstract
Background Variants in the SLC26A4 gene are correlated with nonsyndromic hearing loss with an enlarged vestibular aqueduct (EVA). This study aimed to identify the genetic causes in a Chinese family with EVA, and the pathogenicity of the detected variants. Methods We collected blood samples and clinical data from a pair of deaf twin sisters with EVA and their family members. As controls, a group of 500 normal‐hearing people were enrolled in our study. Twenty‐one exons and flanking splice sites of the SLC26A4 gene were screened for pathogenic mutations by polymerase chain reaction and bidirectional Sanger sequencing. Minigene assays were used to verify whether the novel SLC26A4 intronic mutation influenced the normal splicing of mRNA. Results Hearing loss in the twins with EVA was diagnosed using auditory tests and imaging examinations. Two pathogenic mutations, c.919‐2A>G and c.1614+5G>A were detected in SLC26A4, the latter of which has not been reported in the literature. The minigene expression in vitro confirmed that c.1614+5G>A could cause aberrant splicing, resulting in skipping over exon 14. Conclusions On the SLC26A4 gene, c.1614+5G>A is a pathogenic mutation. This finding enriches the mutational spectrum of the SLC26A4 gene and provides a basis for the genetic diagnosis of EVA.
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Affiliation(s)
- Kai Zhou
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China.,Guangxi Medical University, Nanning, Guangxi, China
| | - Lancheng Huang
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China.,Guangxi Medical University, Nanning, Guangxi, China
| | - Menglong Feng
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China.,Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Xinlei Li
- Medical Genetics Center, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Yi Zhao
- Medical Genetics Center, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Fei Liu
- Research Center of Medical Sciences, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Jiazhang Wei
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Danxue Qin
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Qiutian Lu
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Min Shi
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Shenhong Qu
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Fengzhu Tang
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
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26
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Li M, Nishio SY, Naruse C, Riddell M, Sapski S, Katsuno T, Hikita T, Mizapourshafiyi F, Smith FM, Cooper LT, Lee MG, Asano M, Boettger T, Krueger M, Wietelmann A, Graumann J, Day BW, Boyd AW, Offermanns S, Kitajiri SI, Usami SI, Nakayama M. Digenic inheritance of mutations in EPHA2 and SLC26A4 in Pendred syndrome. Nat Commun 2020; 11:1343. [PMID: 32165640 PMCID: PMC7067772 DOI: 10.1038/s41467-020-15198-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/17/2020] [Indexed: 01/03/2023] Open
Abstract
Enlarged vestibular aqueduct (EVA) is one of the most commonly identified inner ear malformations in hearing loss patients including Pendred syndrome. While biallelic mutations of the SLC26A4 gene, encoding pendrin, causes non-syndromic hearing loss with EVA or Pendred syndrome, a considerable number of patients appear to carry mono-allelic mutation. This suggests faulty pendrin regulatory machinery results in hearing loss. Here we identify EPHA2 as another causative gene of Pendred syndrome with SLC26A4. EphA2 forms a protein complex with pendrin controlling pendrin localization, which is disrupted in some pathogenic forms of pendrin. Moreover, point mutations leading to amino acid substitution in the EPHA2 gene are identified from patients bearing mono-allelic mutation of SLC26A4. Ephrin-B2 binds to EphA2 triggering internalization with pendrin inducing EphA2 autophosphorylation weakly. The identified EphA2 mutants attenuate ephrin-B2- but not ephrin-A1-induced EphA2 internalization with pendrin. Our results uncover an unexpected role of the Eph/ephrin system in epithelial function. While biallelic mutations of the SLC26A4 gene cause non-syndromic hearing loss with enlarged vestibular aqueducts or Pendred syndrome, a considerable number of patients carry mono-allelic mutations. Here the authors identify EPHA2 as another causative gene of Pendred syndrome with SLC26A4.
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Affiliation(s)
- Mengnan Li
- Laboratory for Cell Polarity and Organogenesis, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps-Universität Marburg, Marburg, Germany
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Chie Naruse
- Institute of Laboratory Animals, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Meghan Riddell
- Laboratory for Cell Polarity and Organogenesis, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Sabrina Sapski
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Tatsuya Katsuno
- Department of Otolaryngology - Head and Neck Surgery Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takao Hikita
- Laboratory for Cell Polarity and Organogenesis, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Fatemeh Mizapourshafiyi
- Laboratory for Cell Polarity and Organogenesis, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps-Universität Marburg, Marburg, Germany
| | - Fiona M Smith
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Leanne T Cooper
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Min Goo Lee
- Department of Pharmacology, Yonsei University College of Medicine, Seoul, Korea
| | - Masahide Asano
- Institute of Laboratory Animals, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Thomas Boettger
- Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Marcus Krueger
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Astrid Wietelmann
- MRI and µCT Service Group, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Johannes Graumann
- Scientific Service Group Biomolecular Mass Spectrometry Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,German Centre for Cardiovascular Research (DZHK), Partner Site - Rhine-Main, Berlin, Germany
| | - Bryan W Day
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Andrew W Boyd
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Shin-Ichiro Kitajiri
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Masanori Nakayama
- Laboratory for Cell Polarity and Organogenesis, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany. .,DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps-Universität Marburg, Marburg, Germany. .,Kumamoto University International Research Center for Medical Scinece, Kumamoto, Japan.
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27
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Hasnain MJU, Shoaib M, Qadri S, Afzal B, Anwar T, Abbas SH, Sarwar A, Talha Malik HM, Tariq Pervez M. Computational analysis of functional single nucleotide polymorphisms associated with SLC26A4 gene. PLoS One 2020; 15:e0225368. [PMID: 31971949 PMCID: PMC6977751 DOI: 10.1371/journal.pone.0225368] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Accepted: 11/03/2019] [Indexed: 11/25/2022] Open
Abstract
Single Nucleotide Polymorphisms (SNPs) are the most common candidate mutations in human beings that play a vital role in the genetic basis of certain diseases. Previous studies revealed that Solute Carrier Family 26 Member 4 (SLC26A4) being an essential gene of the multi-faceted transporter family SLC26 facilitates reflexive movement of Iodide into follicular lumen through apical membrane of thyrocyte. SLC26A4 gene encodes Pendred protein, a membrane glycoprotein, highly hydrophobic in nature, present at the apical membrane of thyrocyte functioning as transporter of iodide for thyroid cells. A minor genetic variation in SLC26A4 can cause Pendred syndrome, a syndrome associated with thyroid glands and deafness. In this study, we performed in-silico analysis of 674 missense SNPs of SLC26A4 using different computational platforms. The bunch of tools including SNPNEXUS, SNAP-2, PhD-SNP, SNPs&GO, I-Mutant, ConSurf, and ModPred were used to predict 23 highly confident damaging and disease causing nsSNPs (G209V, G197R, L458P, S427P, Q101P, W472R, N392Y, V359E, R409C, Q235R, R409P, G139V, G497S, H723R, D87G, Y127H, F667C, G334A, G95R, S427C, R291W, Q383H and E384G) that could potentially alter the SLC26A4 gene. Moreover, protein structure prediction, protein-ligand docking and Molecular Dynamics simulation were performed to confirm the impact of two evident alterations (Y127H and G334A) on the protein structure and function.
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Affiliation(s)
| | - Muhammad Shoaib
- Department of Computer Science and Engineering, UET, Lahore, Pakistan
| | - Salman Qadri
- Department of CS & IT, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Bakhtawar Afzal
- Department of Biosciences, COMSATS University, Islamabad, Pakistan
| | - Tehreem Anwar
- Department of Bioinformatics, Virtual University of Pakistan, Lahore, Pakistan
| | - Syed Hassan Abbas
- Department of Bioinformatics, Virtual University of Pakistan, Lahore, Pakistan
| | - Amina Sarwar
- Department of Bioinformatics, Virtual University of Pakistan, Lahore, Pakistan
| | | | - Muhammad Tariq Pervez
- Department of Bioinformatics, Virtual University of Pakistan, Lahore, Pakistan
- * E-mail:
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28
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Touré A. Importance of SLC26 Transmembrane Anion Exchangers in Sperm Post-testicular Maturation and Fertilization Potential. Front Cell Dev Biol 2019; 7:230. [PMID: 31681763 PMCID: PMC6813192 DOI: 10.3389/fcell.2019.00230] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 09/26/2019] [Indexed: 12/17/2022] Open
Abstract
In mammals, sperm cells produced within the testis are structurally differentiated but remain immotile and are unable to fertilize the oocyte unless they undergo a series of maturation events during their transit in the male and female genital tracts. This post-testicular functional maturation is known to rely on the micro-environment of both male and female genital tracts, and is tightly controlled by the pH of their luminal milieus. In particular, within the epididymis, the establishment of a low bicarbonate (HCO3–) concentration contributes to luminal acidification, which is necessary for sperm maturation and subsequent storage in a quiescent state. Following ejaculation, sperm is exposed to the basic pH of the female genital tract and bicarbonate (HCO3–), calcium (Ca2+), and chloride (Cl–) influxes induce biochemical and electrophysiological changes to the sperm cells (cytoplasmic alkalinization, increased cAMP concentration, and protein phosphorylation cascades), which are indispensable for the acquisition of fertilization potential, a process called capacitation. Solute carrier 26 (SLC26) members are conserved membranous proteins that mediate the transport of various anions across the plasma membrane of epithelial cells and constitute important regulators of pH and HCO3– concentration. Most SLC26 members were shown to physically interact and cooperate with the cystic fibrosis transmembrane conductance regulator channel (CFTR) in various epithelia, mainly by stimulating its Cl– channel activity. Among SLC26 members, the function of SLC26A3, A6, and A8 were particularly investigated in the male genital tract and the sperm cells. In this review, we will focus on SLC26s contributions to ionic- and pH-dependent processes during sperm post-testicular maturation. We will specify the current knowledge regarding their functions, based on data from the literature generated by means of in vitro and in vivo studies in knock-out mouse models together with genetic studies of infertile patients. We will also discuss the limits of those studies, the current research gaps and identify some key points for potential developments in this field.
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Affiliation(s)
- Aminata Touré
- INSERM U1016, Centre National de la Recherche Scientifique, UMR 8104, Institut Cochin, Université de Paris, Paris, France
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Generation of a human iPS cell line (CGMH.SLC26A4919-2) from a Pendred syndrome patient carrying SLC26A4 c.919-2A>G splice-site mutation. Stem Cell Res 2019; 40:101524. [PMID: 31415960 DOI: 10.1016/j.scr.2019.101524] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 07/25/2019] [Accepted: 07/30/2019] [Indexed: 11/20/2022] Open
Abstract
SLC26A4 is the second most frequent gene implicated in congenital hearing loss after GJB2 mutations. Here, we report the generation of induced pluripotent stem cells (iPSCs), from a patient who was carrying a homozygous c.919-2A>G variant in the SLC26A4 gene. This is the most common variant of SLC26A4 gene in the Chinese population and the second most prevalent one in other Asian countries. The established patient-derived iPSC displayed all the features of pluripotent stem cell markers and had the ability to differentiate into all of the three germ layers and possessed a normal karyotype.
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Abstract
The epithelium of the kidney collecting duct (CD) is composed mainly of two different types of cells with distinct and complementary functions. CD principal cells traditionally have been considered to have a major role in Na+ and water regulation, while intercalated cells (ICs) were thought to largely modulate acid-base homeostasis. In recent years, our understanding of IC function has improved significantly owing to new research findings. Thus, we now have a new model for CD transport that integrates mechanisms of salt and water reabsorption, K+ homeostasis, and acid-base status between principal cells and ICs. There are three main types of ICs (type A, type B, and non-A, non-B), which first appear in the late distal convoluted tubule or in the connecting segment in a species-dependent manner. ICs can be detected in CD from cortex to the initial part of the inner medulla, although some transport proteins that are key components of ICs also are present in medullary CD, cells considered inner medullary. Of the three types of ICs, each has a distinct morphology and expresses different complements of membrane transport proteins that translate into very different functions in homeostasis and contributions to CD luminal pro-urine composition. This review includes recent discoveries in IC intracellular and paracrine signaling that contributes to acid-base regulation as well as Na+, Cl-, K+, and Ca2+ homeostasis. Thus, these new findings highlight the potential role of ICs as targets for potential hypertension treatments.
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Affiliation(s)
- Renee Rao
- University of Southern California/University Kidney Research Organization, Kidney Research Center, Division of Nephrology and Hypertension, Department of Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA
| | - Vivek Bhalla
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, CA
| | - Núria M Pastor-Soler
- University of Southern California/University Kidney Research Organization, Kidney Research Center, Division of Nephrology and Hypertension, Department of Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA.
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Interleukin-Mediated Pendrin Transcriptional Regulation in Airway and Esophageal Epithelia. Int J Mol Sci 2019; 20:ijms20030731. [PMID: 30744098 PMCID: PMC6386862 DOI: 10.3390/ijms20030731] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/29/2019] [Accepted: 01/29/2019] [Indexed: 12/28/2022] Open
Abstract
Pendrin (SLC26A4), a Cl−/anion exchanger, is expressed at high levels in kidney, thyroid, and inner ear epithelia, where it has an essential role in bicarbonate secretion/chloride reabsorption, iodide accumulation, and endolymph ion balance, respectively. Pendrin is expressed at lower levels in other tissues, such as airways and esophageal epithelia, where it is transcriptionally regulated by the inflammatory cytokines interleukin (IL)-4 and IL-13 through a signal transducer and activator of transcription 6 (STAT6)-mediated pathway. In the airway epithelium, increased pendrin expression during inflammatory diseases leads to imbalances in airway surface liquid thickness and mucin release, while, in the esophageal epithelium, dysregulated pendrin expression is supposed to impact the intracellular pH regulation system. In this review, we discuss some of the recent findings on interleukin-mediated transcriptional regulation of pendrin and how this dysregulation impacts airway and esophagus epithelial homeostasis during inflammatory diseases.
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Zeinali S, Davoudi-Dehaghani E, Mahdieh N, Shirkavand A, Bagherian H, DabbaghBagheri S. SLC26A4 pathogenic variants as a third cause of hearing loss: Role of three exons in DFNB4 deafness in Iran. INDIAN JOURNAL OF OTOLOGY 2019. [DOI: 10.4103/indianjotol.indianjotol_36_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Ming L, Wang Y, Lu W, Sun T. A Mutational Analysis of GJB2, SLC26A4, MT-RNA1, and GJB3 in Children with Nonsyndromic Hearing Loss in the Henan Province of China. Genet Test Mol Biomarkers 2018; 23:51-56. [PMID: 30589569 DOI: 10.1089/gtmb.2018.0146] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Hearing impairment is one of the most common neurosensory disorders afflicting humans. Approximately half of all cases have a genetic etiology. The distribution and frequency of genetic mutations that cause deafness differ significantly by ethnic group and geographic region. METHODS 130 sporadic nonsyndromic hearing loss (NSHL) children from the Henan province were subjected to microarray-based mutation detection. Nine pathogenic mutations were detected in four of the most common deafness-related genes (GJB2, GJB3, SLC26A4, and MT-RNA1). RESULTS Fifty percent of the analyzed patients (65/130) were shown to have genetic defects known to be related to deafness. Slightly >30% (41/130) had biallelic pathogenic mutations. One patient had pathogenic mutations in their mitochondrial genes (MT-RNA1); no mutations were detected in the GJB3 gene. Twenty-three (17.69%) patients were carriers of a single mutation in a recessive gene; these findings alone, however, cannot be interpreted as a cause of hearing loss. Utilizing this molecular strategy, we were able to arrive at a conclusive diagnosis for 42 of the NSHL children. CONCLUSION Genetic factors play a major role in sporadic NSHL patients from the Henan province, but it is clear that our screen needs to be expanded to include additional genes and alleles. Screening of potential pathogenic genes is important for patient risk assessment.
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Affiliation(s)
- Liang Ming
- 1 Key Clinical Laboratory of Henan Province, Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
| | - Yangxia Wang
- 1 Key Clinical Laboratory of Henan Province, Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
| | - Wei Lu
- 2 Department of Otology, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
| | - Ting Sun
- 1 Key Clinical Laboratory of Henan Province, Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
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Cirello V, Giorgini V, Castronovo C, Marelli S, Mainini E, Sironi A, Recalcati MP, Pessina M, Giardino D, Larizza L, Persani L, Finelli P, Russo S, Fugazzola L. Segmental Maternal UPD of Chromosome 7q in a Patient With Pendred and Silver Russell Syndromes-Like Features. Front Genet 2018; 9:600. [PMID: 30555519 PMCID: PMC6284021 DOI: 10.3389/fgene.2018.00600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 11/15/2018] [Indexed: 11/24/2022] Open
Abstract
Pendred syndrome (PS) is an autosomal recessive disorder due to mutations in the SLC26A4 gene (chr7q22. 3) and characterized by sensorineural hearing loss and variable thyroid phenotype. Silver-Russell syndrome (SRS) is a heterogeneous imprinting disorder including severe intrauterine and postnatal growth retardation, and dysmorphic features. Maternal uniparental disomy of either the whole chromosome 7 (upd(7)mat) or 7q (upd(7q)mat) is one of the multiple mechanisms impacting the expression of imprinted genes in SRS, and is associated with milder clinical features. Here, we report genetic and clinical characterization of a female child with PS, postnatal growth retardation, and minor dysmorphic features. A gross homozygous deletion of SLC26A4 exons 17-20 was suspected by Sanger sequencing and then confirmed by array-CGH. Moreover, an insertion of about 1 kb of the CCDC126 gene (7p15.3), which does not appear to be clinically relevant, was detected. The possible occurrence of a balanced rearrangement between 7p and 7q was excluded. The absence of the deletion in the father led to the investigation of upd, and microsatellite segregation analysis revealed a segmental 7q (upd(7q)mat), leading to SLC26A4 homozygosity and responsible for both PS and SRS-like traits. The proband matched 3 out of 6 major SRS criteria. In conclusion, this is the first report of uniparental isodisomy encompassing almost the whole long arm of chromosome 7 resulting in PS and SRS-like features. Whereas, the inner ear phenotype of PS is typical, the clinical features suggestive of SRS might have been overlooked.
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Affiliation(s)
- Valentina Cirello
- Division of Endocrine and Metabolic Diseases, Laboratory of Endocrine and Metabolic Research, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Valentina Giorgini
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Chiara Castronovo
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Susan Marelli
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute, IRCCS Eugenio Medea, Lecco, Italy
| | - Ester Mainini
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Alessandra Sironi
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy.,Department of Medical Biotechnologies and Translational Medicine, University of Milan, Milan, Italy
| | - Maria Paola Recalcati
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Marco Pessina
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute, IRCCS Eugenio Medea, Lecco, Italy
| | - Daniela Giardino
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Lidia Larizza
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Luca Persani
- Division of Endocrine and Metabolic Diseases, Laboratory of Endocrine and Metabolic Research, IRCCS Istituto Auxologico Italiano, Milan, Italy.,Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Palma Finelli
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy.,Department of Medical Biotechnologies and Translational Medicine, University of Milan, Milan, Italy
| | - Silvia Russo
- Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Laura Fugazzola
- Division of Endocrine and Metabolic Diseases, Laboratory of Endocrine and Metabolic Research, IRCCS Istituto Auxologico Italiano, Milan, Italy.,Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
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Lee JH, Lee MY, Lim Y, Knowles J, Kim HW. Auditory disorders and future therapies with delivery systems. J Tissue Eng 2018; 9:2041731418808455. [PMID: 30397431 PMCID: PMC6207966 DOI: 10.1177/2041731418808455] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/14/2018] [Indexed: 12/24/2022] Open
Abstract
Auditory function takes a major part in human life. While sensorineural hearing loss is related with many factors including genetic disorders, age and noise, the clear causes are not well understood. Even more, the currently available treatments with drugs cause side effects, which thus are considered suboptimal. Here, we communicate the delivery systems with biomaterials that can be possible therapeutic options to restore hearing and vestibular functions. We introduce briefly the various pathological factors related with hearing loss and the limitation of current therapies, detail the recent studies on delivery systems including nanoparticles and hydrogels and discuss future clinical availability.
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Affiliation(s)
- Jung-Hwan Lee
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea.,Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea.,UCL Eastman - Korea Dental Medicine Innovation Center, Dankook University, Cheonan, Republic of Korea
| | - Min Young Lee
- Beckman Laser Institute Korea, College of Medicine, Dankook University, Cheonan, Republic of Korea.,Department of Otolaryngology-Head & Neck Surgery, College of Medicine, Dankook University, Cheonan, Republic of Korea
| | - Yohan Lim
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea
| | - Jonathan Knowles
- UCL Eastman - Korea Dental Medicine Innovation Center, Dankook University, Cheonan, Republic of Korea.,Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, Republic of Korea.,Biomaterials and Tissue Engineering Research Department, UCL Eastman Dental Institute, London, UK.,The Discoveries Centre for Regenerative and Precision Medicine, London, UK
| | - Hae-Won Kim
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea.,Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea.,UCL Eastman - Korea Dental Medicine Innovation Center, Dankook University, Cheonan, Republic of Korea.,Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, Republic of Korea
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Talbi S, Bonnet C, Riahi Z, Boudjenah F, Dahmani M, Hardelin JP, Wong Jun Tai F, Louha M, Ammar-Khodja F, Petit C. Genetic heterogeneity of congenital hearing impairment in Algerians from the Ghardaïa province. Int J Pediatr Otorhinolaryngol 2018; 112:1-5. [PMID: 30055715 DOI: 10.1016/j.ijporl.2018.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/07/2018] [Accepted: 06/08/2018] [Indexed: 01/04/2023]
Abstract
BACKGROUND Consanguinity rate is high in Algeria, and the population is thus at high risk for genetic diseases transmitted on an autosomal recessive mode. Inherited congenital hearing impairment (HI) is a highly heterogeneous disorder, which affects approximately 1 in 800 Algerian newborns. Several hundreds of genes responsible for deafness have been reported among which more than one hundred are responsible for isolated deafness, of which 19 have already been reported to be involved in the Algerian population. This study focuses on patients from the Ghardaïa province, an ethnically and geographically isolated region of Southern Algeria that has the highest consanguinity rate in the country (56%). METHODS Eleven families, with at least two related members experiencing moderate to profound congenital HI, were recruited and screened for mutations in known HI genes. RESULTS A preliminary screening for common mutations in GJB2 and GJB6 identified the prevalent GJB2:c.35delG mutation in four families. Targeted exome sequencing further identified the causal mutations in the remaining seven families: CIB2:c.97C > T; p.(Arg33*), MYO7A:c.470+1G > A; p.(?), and SLC26A4:c.410C > T; p.(Ser137Leu) biallelic mutations in two families each, and a TECTA:c.2743 A > G; p.(Ile915Val) monoallelic mutation in the only family with autosomal dominant transmission of the HI. Of note, the missense mutations of SLC26A4 and TECTA had not been previously reported. CONCLUSION These results further substantiate the genetic heterogeneity of HI, even in reportedly isolated populations. However, several families may harbor the same mutations as a result of a long history of marriages between relatives. This study has important implications for the HI molecular diagnosis strategy, and to develop genetic counseling for families originating from the Ghardaïa province of Algeria.
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Affiliation(s)
- Sonia Talbi
- Equipe de Génétique, Laboratoire de Biologie Moléculaire, Faculté des Sciences Biologiques, Université des Sciences et de la Technologie Houari Boumédiène, Algiers, Algeria
| | - Crystel Bonnet
- Inserm UMRS 1120 /Institut Pasteur/Sorbonne University, Paris, France
| | - Zied Riahi
- Inserm UMRS 1120 /Institut Pasteur/Sorbonne University, Paris, France
| | - Farid Boudjenah
- ENT Department, Frantz Fanon Hospital, Bejaia, Algeria; ENT Department, Sidi Belloua Hospital, Tizi-Ouzou, Algeria
| | - Malika Dahmani
- Equipe de Génétique, Laboratoire de Biologie Moléculaire, Faculté des Sciences Biologiques, Université des Sciences et de la Technologie Houari Boumédiène, Algiers, Algeria
| | | | | | - Malek Louha
- Biochemistry Department, APHP - Armand Trousseau Hospital, Paris, France
| | - Fatima Ammar-Khodja
- Equipe de Génétique, Laboratoire de Biologie Moléculaire, Faculté des Sciences Biologiques, Université des Sciences et de la Technologie Houari Boumédiène, Algiers, Algeria
| | - Christine Petit
- Inserm UMRS 1120 /Institut Pasteur/Sorbonne University, Paris, France; Collège de France, Paris, France.
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Abstract
PURPOSE OF REVIEW The increased availability of next generation sequencing has enabled a rapid progress in the discovery of genetic variants associated with vestibular disorders. We have summarized molecular genetics finding in vestibular syndromes during the last 18 months. RECENT FINDINGS Genetic studies continue to shed light on the genetic background of vestibular disorders. Novel genes affecting brain development and otolith biogenesis have been associated with motion sickness. Exome sequencing has made possible to identify three rare single nucleotide variants in PRKCB, DPT and SEMA3D linked with familial Meniere disease. Moreover, superior canal dehiscence syndrome might be related with variants in CDH3 gene, by increasing risk of its development. On the other hand, the association between vestibular schwannoma and enlarged vestibular aqueduct with variants in NF2 and SLC26A4, respectively, seems increasingly clear. Finally, the use of mouse models is allowing further progress in the development gene therapy for hearing and vestibular monogenic disorders. SUMMARY Most of episodic or progressive syndromes show familial clustering. A detailed phenotyping with a complete familial history of vestibular symptoms is required to conduct a genetic study. Progress in these studies will allow us to understand diseases mechanisms and improve their current medical treatments.
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Nonose RW, Lezirovitz K, de Mello Auricchio MTB, Batissoco AC, Yamamoto GL, Mingroni-Netto RC. Mutation analysis of SLC26A4 (Pendrin) gene in a Brazilian sample of hearing-impaired subjects. BMC MEDICAL GENETICS 2018; 19:73. [PMID: 29739340 PMCID: PMC5941635 DOI: 10.1186/s12881-018-0585-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 04/19/2018] [Indexed: 12/18/2022]
Abstract
Background Mutations in the SLC26A4 gene are associated with Pendred syndrome and autosomal recessive non-syndromic deafness (DFNB4). Both disorders have similar audiologic characteristics: bilateral hearing loss, often severe or profound, which may be associated with abnormalities of the inner ear, such as dilatation of the vestibular aqueduct or Mondini dysplasia. But, in Pendred syndrome (OMIM #274600), with autosomal recessive inheritance, besides congenital sensorineural deafness, goiter or thyroid dysfunctions are frequently present. The aim of this study was to determine whether mutations in SLC26A4 are a frequent cause of hereditary deafness in Brazilian patients. Methods Microsatellite haplotypes linked to SLC26A4 were investigated in 68 families presenting autosomal recessive non-syndromic deafness. In the probands of the 16 families presenting segregation consistent with linkage to SLC26A4, Sanger sequencing of the 20 coding exons was performed. In an additional sample of 15 individuals with suspected Pendred syndrome, because of the presence of hypothyroidism or cochleovestibular malformations, the SLC26A4 gene coding region was also sequenced. Results In two of the 16 families with indication of linkage to SLC26A4, the probands were found to be compound heterozygotes for probably pathogenic different mutations: three novel (c.1003 T > G (p. F335 V), c.1553G > A (p.W518X), c.2235 + 2 T > C (IVS19 + 2 T > C), and one already described, c.84C > A (p.S28R). Two of the 15 individuals with suspected Pendred syndrome because of hypothyreoidism or cochleovestibular malformations were monoallelic for likely pathogenic mutations: a splice mutation (IVS7 + 2 T > C) and the previously described c.1246A > C (p.T416P). Pathogenic copy number variations were excluded in the monoallelic cases and in those with normal results after Sanger sequencing. Additional mutations in the SLC26A4 gene or other definite molecular cause for deafness were not identified in the monoallelic patients, after exome sequencing. Conclusions Biallelic pathogenic mutations in SLC26A4 explained ~ 3% of cases selected because of autosomal recessive deafness. Monoallelic mutations were present in ~ 13% of isolated cases of deafness with cochleovestibular malformations or suspected Pendred syndrome. These data reinforce the importance of mutation screening of SLC26A4 in Brazilian subjects and highlight the elevated frequency of monoallelic patients.
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Affiliation(s)
- Renata Watanabe Nonose
- Centro de Pesquisas sobre o Genoma Humano e Células-Tronco, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Karina Lezirovitz
- Centro de Pesquisas sobre o Genoma Humano e Células-Tronco, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Investigação Médica/LIM32 do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Maria Teresa Balester de Mello Auricchio
- Centro de Pesquisas sobre o Genoma Humano e Células-Tronco, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Ana Carla Batissoco
- Centro de Pesquisas sobre o Genoma Humano e Células-Tronco, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Guilherme Lopes Yamamoto
- Centro de Pesquisas sobre o Genoma Humano e Células-Tronco, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Regina Célia Mingroni-Netto
- Centro de Pesquisas sobre o Genoma Humano e Células-Tronco, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.
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Huang J, Kim D, Shan J, Abu‐Arish A, Luo Y, Hanrahan JW. Most bicarbonate secretion by Calu-3 cells is mediated by CFTR and independent of pendrin. Physiol Rep 2018; 6:e13641. [PMID: 29536650 PMCID: PMC5849580 DOI: 10.14814/phy2.13641] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 02/10/2018] [Accepted: 02/12/2018] [Indexed: 11/24/2022] Open
Abstract
Bicarbonate plays an important role in airway host defense, however, its transport mechanisms remain uncertain. Here we examined the relative contributions of the anion channel CFTR (cystic fibrosis transmembrane conductance regulator, ABCC7) and the anion exchanger pendrin (SLC26A4) to HCO3- secretion by the human airway cell line Calu-3. Pendrin and CFTR were both detected in parental Calu-3 cells, although mRNA and protein expression appeared higher for CFTR than for pendrin. Targeting pendrin transcripts with lentiviral shRNA reduced pendrin detection by immunofluorescence staining but did not alter the rates of HCO3- or fluid secretion, HCO3- transport under pH-stat conditions, or net HCO3- flux across basolaterally permeabilized monolayers. Intracellular pH varied with step changes in apical Cl- and HCO3- concentrations in control and pendrin knockdown Calu-3 cells, but not in CFTR deficient cells. Exposure to the proinflammatory cytokine IL-4, which strongly upregulates pendrin expression in airway surface epithelia, had little effect on Calu-3 pendrin expression and did not alter fluid or HCO3- secretion. Similar results were obtained using air-liquid interface and submerged cultures, although CFTR and pendrin mRNA expression were both lower when cells were cultured under submerged conditions. While the conclusions cannot be extrapolated to other airway epithelia, the present results demonstrate that most HCO3- secretion by Calu-3 cells is mediated by CFTR.
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Affiliation(s)
- Junwei Huang
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
- Present address:
AbbVie Bioresearch CenterAbbVie Inc.381 Plantation St.WorcesterMA01605
| | - Dusik Kim
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
| | - Jiajie Shan
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
- Present address:
School of MedicineSouth China University of TechnologyGuangzhou University TownPanyu DistrictGuangzhouChina
| | - Asmahan Abu‐Arish
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
| | - Yishan Luo
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
| | - John W. Hanrahan
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
- Research Institute‐McGill University Health CentreMontréalQuébecCanada
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40
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Andharia N, Hayashi M, Matsuda H. Electrophysiological properties of anion exchangers in the luminal membrane of guinea pig pancreatic duct cells. Pflugers Arch 2018; 470:897-907. [PMID: 29399744 PMCID: PMC5945753 DOI: 10.1007/s00424-018-2116-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 01/10/2018] [Accepted: 01/23/2018] [Indexed: 12/12/2022]
Abstract
The pancreatic duct epithelium secretes the HCO3−-rich pancreatic juice. The HCO3− transport across the luminal membrane has been proposed to be mediated by SLC26A Cl−–HCO3− exchangers. To examine the electrophysiological properties of Cl−–HCO3− exchangers, we directly measured HCO3− conductance in the luminal membrane of the interlobular pancreatic duct cells from guinea pigs using an inside-out patch-clamp technique. Intracellular HCO3− increased the HCO3− conductance with a half-maximal effective concentration value of approximately 30 mM. The selectivity sequence based on permeability ratios was SCN− (1.4) > Cl− (1.2) = gluconate (1.1) = I− (1.1) = HCO3− (1.0) > methanesulfonate (0.6). The sequence of the relative conductance was HCO3− (1.0) > SCN− (0.7) = I− (0.7) > Cl− (0.5) = gluconate (0.4) > methanesulfonate (0.2). The current dependent on intracellular HCO3− was reduced by replacement of extracellular Cl− with gluconate or by H2DIDS, an inhibitor of Cl−–HCO3− exchangers. RT-PCR analysis revealed that the interlobular and main ducts expressed all SLC26A family members except Slc26a5 and Slc26a8. SLC26A1, SLC26A4, SLC26A6, and SLC26A10 were found to be localized to the luminal membrane of the guinea pig pancreatic duct by immunohistochemistry. These results demonstrate that these SLC26A Cl−–HCO3− exchangers may mediate the electrogenic HCO3− transport through the luminal membrane and may be involved in pancreatic secretion in guinea pig ducts.
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Affiliation(s)
- N Andharia
- Department of Physiology, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, 573-1010, Japan
| | - M Hayashi
- Department of Physiology, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, 573-1010, Japan.
| | - H Matsuda
- Department of Physiology, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, 573-1010, Japan
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41
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Yang SM, Liu Y, Liu C, Yin AH, Wu YF, Zheng XE, Yang HM, Yang J. Hearing-loss-associated gene detection in neonatal intensive care unit. J Matern Fetal Neonatal Med 2018; 31:284-288. [PMID: 28093008 DOI: 10.1080/14767058.2017.1282454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To investigate the frequency and mutation spectrum of hearing loss-associated gene mutation in Neonatal Intensive Care Unit (NICU). METHODS Neonates (n=2305) admitted to NICU were enrolled in this study. Nine prominent hearing loss-associated genes, GJB2 (35 del G, 176 del 16,235 del C, 299 del AT), GJB3 (538 C > T), SLC26A4 (IVS7-2A > G, 2168 A > G) and mtDNA 12S rRNA(1555 A > G, 1494 C > T), were detected. RESULT There were 73 cases hearing-loss-associated gene mutation among 2305 cases, the mutation frequency was 3.1%, with 40 cases GJB2 (235del C) mutation (54.8%), 6 cases GJB2 (299 del AT) mutation (8.2%), 21 cases SLC26A4 (IVS 7-2 A > G) mutation (28.7%), 4 cases SLC26A4 (2168 A > G) mutation (5.5%), 2 cases of GJB2 (235del C) combined SLC26A4 (IVS 7-2 A > G, 2168 A > G) mutation (2.8%). Among 73 gene mutation cases, preterm neonates presented in 18 cases, accounting for 24.7% (18/73); hyperbilirubinemia in 13 cases, accounting for 17.8% (13/73); Torch Syndrome in 15 cases, with 12 cases CMV, 2 cases rubella, 1 case toxoplasm, respectively, totally accounting for 20.54% (15/73); neonatal pneumonia in 12 cases, accounting for 16.4% (12/73); birth asphyxia in 5 cases, accounting for 6.9% (5/73); sepsis in 5 cases, accounting for 6.9% (5/73); others in 5 cases, accounting for 6.8% (5/73) . CONCLUSIONS The frequency of hearing loss-associated gene mutation was higher in NICU.There were hearing loss-associated gene mutations in the NICU, suggesting this mutation may complicate with perinatal high-risk factors.
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Affiliation(s)
- S M Yang
- a Department of Neonatology , Guangdong Women and Children Hospital , Guangzhou , China
| | - Ying Liu
- a Department of Neonatology , Guangdong Women and Children Hospital , Guangzhou , China
| | - C Liu
- b Prenatal Diagnosis Centre, Guangdong Women and Children Hospital , Guangzhou , China
| | - A H Yin
- b Prenatal Diagnosis Centre, Guangdong Women and Children Hospital , Guangzhou , China
| | - Y F Wu
- c Department of ENT , Guangdong Women and Children Hospital , Guangzhou , China
| | - X E Zheng
- a Department of Neonatology , Guangdong Women and Children Hospital , Guangzhou , China
| | - H M Yang
- a Department of Neonatology , Guangdong Women and Children Hospital , Guangzhou , China
| | - J Yang
- a Department of Neonatology , Guangdong Women and Children Hospital , Guangzhou , China
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Roesch S, Bernardinelli E, Nofziger C, Tóth M, Patsch W, Rasp G, Paulmichl M, Dossena S. Functional Testing of SLC26A4 Variants-Clinical and Molecular Analysis of a Cohort with Enlarged Vestibular Aqueduct from Austria. Int J Mol Sci 2018; 19:ijms19010209. [PMID: 29320412 PMCID: PMC5796158 DOI: 10.3390/ijms19010209] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 12/20/2017] [Accepted: 12/28/2017] [Indexed: 12/29/2022] Open
Abstract
The prevalence and spectrum of sequence alterations in the SLC26A4 gene, which codes for the anion exchanger pendrin, are population-specific and account for at least 50% of cases of non-syndromic hearing loss associated with an enlarged vestibular aqueduct. A cohort of nineteen patients from Austria with hearing loss and a radiological alteration of the vestibular aqueduct underwent Sanger sequencing of SLC26A4 and GJB2, coding for connexin 26. The pathogenicity of sequence alterations detected was assessed by determining ion transport and molecular features of the corresponding SLC26A4 protein variants. In this group, four uncharacterized sequence alterations within the SLC26A4 coding region were found. Three of these lead to protein variants with abnormal functional and molecular features, while one should be considered with no pathogenic potential. Pathogenic SLC26A4 sequence alterations were only found in 12% of patients. SLC26A4 sequence alterations commonly found in other Caucasian populations were not detected. This survey represents the first study on the prevalence and spectrum of SLC26A4 sequence alterations in an Austrian cohort and further suggests that genetic testing should always be integrated with functional characterization and determination of the molecular features of protein variants in order to unequivocally identify or exclude a causal link between genotype and phenotype.
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Affiliation(s)
- Sebastian Roesch
- Department of Otorhinolaryngology, Head and Neck Surgery, Paracelsus Medical University, Müllner Hauptstraße 48, A-5020 Salzburg, Austria.
| | - Emanuele Bernardinelli
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, Strubergasse 21, A-5020 Salzburg, Austria.
| | - Charity Nofziger
- PharmGenetix Gmbh, Sonystrasse 20, A-5081 Niederalm Anif, Austria.
| | - Miklós Tóth
- Department of Otorhinolaryngology, Head & Neck Surgery and Oncology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20251 Hamburg, Germany.
| | - Wolfgang Patsch
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, Strubergasse 21, A-5020 Salzburg, Austria.
| | - Gerd Rasp
- Department of Otorhinolaryngology, Head and Neck Surgery, Paracelsus Medical University, Müllner Hauptstraße 48, A-5020 Salzburg, Austria.
| | - Markus Paulmichl
- Center for Health and Bioresources, Austrian Institute of Technology, Muthgasse 11, A-1190 Vienna, Austria.
| | - Silvia Dossena
- Institute of Pharmacology and Toxicology, Paracelsus Medical University, Strubergasse 21, A-5020 Salzburg, Austria.
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Karaca T, Demirtas S, Uzun Goren D. Pendrin and sodium/iodide symporter protein expression in the testicular tissue of normal and diabetic rats in prepubertal and post pubertal stages. IRANIAN JOURNAL OF VETERINARY RESEARCH 2018; 19:255-261. [PMID: 30774665 PMCID: PMC6361603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 05/16/2018] [Accepted: 06/03/2018] [Indexed: 06/09/2023]
Abstract
Pendrin (PDS) and sodium/iodide symporter (NIS) are transmembrane proteins that are located in numerous tissue types, particularly thyroid follicular epithelial cells, where they are entrusted with the regulation of iodine molecules. In the present study, we aimed to clarify changes in PDS and NIS protein expression, in the testicular tissue of prepubertal and post pubertal rats at normal or diabetic conditions. Forty Wistar albino male rats (20 prepubertal and 20 post pubertal) were divided into four groups, as follows: group I was prepubertal control, group II was prepubertal diabetic (60 mg/kg intraperitoneal [ip] streptozotocin [STZ]), group III was post pubertal control, and group IV was post pubertal diabetic (60 mg/kg ip STZ). Ki67 immunoreactivity decreased in testicular tissue of both the prepubertal and post pubertal diabetic groups; the apoptotic tubule index and apoptotic cell number increased in the diabetic groups as compared to the control groups. Pendrin immunoreactivity was detected in seminiferous tubules and Leydig cells; and was significantly reduced in the diabetic groups (P<0.05). The number of cells positive for NIS was significantly decreased in prepubertal and post pubertal rats with diabetes, compared to the controls. Enzyme-linked immunosorbent assay (ELISA) analysis showed that PDS and NIS values were significantly reduced in the prepubertal and post pubertal diabetic groups as compared to the control groups. Our results indicate a potential relationship between puberty and PDS and NIS expression in rat testicular tissue and showed the decreasing effects of diabetes on PDS and NIS expression in testicular tissues in rats.
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Affiliation(s)
- T. Karaca
- Department of Histology and Embryology, Faculty of Medicine, Trakya University, Balkan Campus, 22030, Edirne, Turkey
| | - S. Demirtas
- Department of Histology and Embryology, Faculty of Medicine, Trakya University, Balkan Campus, 22030, Edirne, Turkey
- Ph.D. Student, Department of Histology and Embryology, Institute of Health Sciences, Trakya University, Balkan Campus, 22030, Edirne, Turkey
| | - D. Uzun Goren
- Department of Histology and Embryology, Faculty of Medicine, Trakya University, Balkan Campus, 22030, Edirne, Turkey
- Ph.D. Student, Department of Histology and Embryology, Institute of Health Sciences, Trakya University, Balkan Campus, 22030, Edirne, Turkey
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Fettiplace R. Hair Cell Transduction, Tuning, and Synaptic Transmission in the Mammalian Cochlea. Compr Physiol 2017; 7:1197-1227. [PMID: 28915323 DOI: 10.1002/cphy.c160049] [Citation(s) in RCA: 191] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Sound pressure fluctuations striking the ear are conveyed to the cochlea, where they vibrate the basilar membrane on which sit hair cells, the mechanoreceptors of the inner ear. Recordings of hair cell electrical responses have shown that they transduce sound via submicrometer deflections of their hair bundles, which are arrays of interconnected stereocilia containing the mechanoelectrical transducer (MET) channels. MET channels are activated by tension in extracellular tip links bridging adjacent stereocilia, and they can respond within microseconds to nanometer displacements of the bundle, facilitated by multiple processes of Ca2+-dependent adaptation. Studies of mouse mutants have produced much detail about the molecular organization of the stereocilia, the tip links and their attachment sites, and the MET channels localized to the lower end of each tip link. The mammalian cochlea contains two categories of hair cells. Inner hair cells relay acoustic information via multiple ribbon synapses that transmit rapidly without rundown. Outer hair cells are important for amplifying sound-evoked vibrations. The amplification mechanism primarily involves contractions of the outer hair cells, which are driven by changes in membrane potential and mediated by prestin, a motor protein in the outer hair cell lateral membrane. Different sound frequencies are separated along the cochlea, with each hair cell being tuned to a narrow frequency range; amplification sharpens the frequency resolution and augments sensitivity 100-fold around the cell's characteristic frequency. Genetic mutations and environmental factors such as acoustic overstimulation cause hearing loss through irreversible damage to the hair cells or degeneration of inner hair cell synapses. © 2017 American Physiological Society. Compr Physiol 7:1197-1227, 2017.
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Affiliation(s)
- Robert Fettiplace
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
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Abstract
Congenital hypothyroidism (CH) is the most common inborn endocrine disorder and causes significant morbidity. To date, we are only aware of the molecular basis responsible for the defects in a small portion of patients with CH. A better understanding of the pathophysiology of these cases at the genetic and molecular basis provides useful information for proper counseling to patients and their families a well as for the development of better targeted therapies. This article provides a succinct outline of the pathophysiology and genetics of the known causes of thyroid dysgenesis, dyshormonogenesis, and syndrome of impaired sensitivity to thyroid hormone.
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Affiliation(s)
- Zeina C Hannoush
- Department of Medicine, University of Miami Miller School of Medicine, 1120 NW 14th Street, Suite 310F, Miami, FL 33136, USA
| | - Roy E Weiss
- Department of Medicine, University of Miami Miller School of Medicine, 1120 NW 14th Street, Suite 310F, Miami, FL 33136, USA.
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Runggaldier D, Pradas LG, Neckel PH, Mack AF, Hirt B, Gleiser C. Claudin expression in the rat endolymphatic duct and sac - first insights into regulation of the paracellular barrier by vasopressin. Sci Rep 2017; 7:45482. [PMID: 28374851 PMCID: PMC5379655 DOI: 10.1038/srep45482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/28/2017] [Indexed: 12/13/2022] Open
Abstract
Hearing and balance functions of the inner ear rely on the homeostasis of the endolymphatic fluid. When disturbed, pathologic endolymphatic hydrops evolves as observed in Menière’s disease. The molecular basis of inner ear fluid regulation across the endolymphatic epithelium is largely unknown. In this study we identified the specific expression of the tight junction (TJ) molecules Claudin 3, 4, 6, 7, 8, 10, and 16 in epithelial preparations of the rat inner ear endolymphatic duct (ED) and endolymphatic sac (ES) by high-throughput qPCR and immunofluorescence confocal microscopy. Further we showed that Claudin 4 in the ES is a target of arginine-vasopressin (AVP), a hormone elevated in Menière’s disease. Moreover, our transmission-electron microscopy (TEM) analysis revealed that the TJs of the ED were shallow and shorter compared to the TJ of the ES indicating facilitation of a paracellular fluid transport across the ED epithelium. The significant differences in the subcellular localization of the barrier-forming protein Claudin 3 between the ED and ES epithelium further support the TEM observations. Our results indicate a high relevance of Claudin 3 and Claudin 4 as important paracellular barrier molecules in the ED and ES epithelium with potential involvement in the pathophysiology of Menière’s disease.
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Affiliation(s)
- Daniel Runggaldier
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Lidia Garcia Pradas
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Peter H Neckel
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Andreas F Mack
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Bernhard Hirt
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Corinna Gleiser
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
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Mapping pathogenic mutations suggests an innovative structural model for the pendrin (SLC26A4) transmembrane domain. Biochimie 2016; 132:109-120. [PMID: 27771369 DOI: 10.1016/j.biochi.2016.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 10/03/2016] [Indexed: 12/16/2022]
Abstract
Human pendrin (SLC26A4) is an anion transporter mostly expressed in the inner ear, thyroid and kidney. SLC26A4 gene mutations are associated with a broad phenotypic spectrum, including Pendred Syndrome and non-syndromic hearing loss with enlarged vestibular aqueduct (ns-EVA). No experimental structure of pendrin is currently available, making phenotype-genotype correlations difficult as predictions of transmembrane (TM) segments vary in number. Here, we propose a novel three-dimensional (3D) pendrin transmembrane domain model based on the SLC26Dg transporter. The resulting 14 TM topology was found to include two non-canonical transmembrane segments crucial for pendrin activity. Mutation mapping of 147 clinically validated pathological mutations shows that most affect two previously undescribed TM regions.
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48
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Nin F, Yoshida T, Sawamura S, Ogata G, Ota T, Higuchi T, Murakami S, Doi K, Kurachi Y, Hibino H. The unique electrical properties in an extracellular fluid of the mammalian cochlea; their functional roles, homeostatic processes, and pathological significance. Pflugers Arch 2016; 468:1637-49. [PMID: 27568193 PMCID: PMC5026722 DOI: 10.1007/s00424-016-1871-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 08/16/2016] [Indexed: 12/13/2022]
Abstract
The cochlea of the mammalian inner ear contains an endolymph that exhibits an endocochlear potential (EP) of +80 mV with a [K(+)] of 150 mM. This unusual extracellular solution is maintained by the cochlear lateral wall, a double-layered epithelial-like tissue. Acoustic stimuli allow endolymphatic K(+) to enter sensory hair cells and excite them. The positive EP accelerates this K(+) influx, thereby sensitizing hearing. K(+) exits from hair cells and circulates back to the lateral wall, which unidirectionally transports K(+) to the endolymph. In vivo electrophysiological assays demonstrated that the EP stems primarily from two K(+) diffusion potentials yielded by [K(+)] gradients between intracellular and extracellular compartments in the lateral wall. Such gradients seem to be controlled by ion channels and transporters expressed in particular membrane domains of the two layers. Analyses of human deafness genes and genetically modified mice suggested the contribution of these channels and transporters to EP and hearing. A computational model, which reconstitutes unidirectional K(+) transport by incorporating channels and transporters in the lateral wall and connects this transport to hair cell transcellular K(+) fluxes, simulates the circulation current flowing between the endolymph and the perilymph. In this model, modulation of the circulation current profile accounts for the processes leading to EP loss under pathological conditions. This article not only summarizes the unique physiological and molecular mechanisms underlying homeostasis of the EP and their pathological relevance but also describes the interplay between EP and circulation current.
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Affiliation(s)
- Fumiaki Nin
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Takamasa Yoshida
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
- Center for Transdisciplinary Research, Niigata University, Niigata, 950-2181, Japan
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Seishiro Sawamura
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Genki Ogata
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
- Center for Transdisciplinary Research, Niigata University, Niigata, 950-2181, Japan
| | - Takeru Ota
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Taiga Higuchi
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan
| | - Shingo Murakami
- Division of Molecular and Cellular Pharmacology, Department of Pharmacology, Osaka University, Osaka, 565-0871, Japan
- Center for Advanced Medical Engineering and Informatics, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan
- Department of Physiology, School of Medicine, Toho University, Tokyo, 143-8540, Japan
| | - Katsumi Doi
- Department of Otolaryngology, Kindai University Faculty of Medicine, Osaka, 589-8511, Japan
| | - Yoshihisa Kurachi
- Division of Molecular and Cellular Pharmacology, Department of Pharmacology, Osaka University, Osaka, 565-0871, Japan
- Center for Advanced Medical Engineering and Informatics, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan
| | - Hiroshi Hibino
- Department of Molecular Physiology, Niigata University School of Medicine, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, 951-8510, Japan.
- Center for Transdisciplinary Research, Niigata University, Niigata, 950-2181, Japan.
- AMED-CREST, AMED, Niigata, Japan.
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Kim BG, Yoo TH, Yoo JE, Seo YJ, Jung J, Choi JY. Resistance to hypertension and high Cl - excretion in humans with SLC26A4 mutations. Clin Genet 2016; 91:448-452. [PMID: 27090054 DOI: 10.1111/cge.12789] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 04/12/2016] [Accepted: 04/14/2016] [Indexed: 10/21/2022]
Abstract
Pendrin is a membrane transporter encoded by solute carrier family26A4 (SLC26A4). Mutations in this gene are known to cause hearing loss, and recent data from animal studies indicate a link between pendrin expression and hypertension; although, this association in humans is unclear. To clarify this issue, we investigated the influence of pendrin on blood pressure by analyzing demographic and biochemical data - including blood pressure and urinary electrolyte excretion - in patients with bi-allelic SLC26A4 mutations. Systolic and diastolic blood pressure and the left ventricular hypertrophy index were lower in subjects with pendrin mutations than in controls. In addition, fractional excretion of Na+ and Cl- was increased and serum renin, angiotensin I and II levels were higher in subjects with pendrin mutations as compared to controls. Thus, patients with impaired pendrin function are likely to be resistant to high blood pressure due to enhanced urinary Na+ /Cl- excretion. These results suggest that pendrin may regulate blood pressure through increased urinary salt excretion.
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Affiliation(s)
- B G Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Soonchunhyang University, College of Medicine, Bucheon, Korea
| | - T-H Yoo
- Department of Internal Medicine, Yonsei University, College of Medicine, Seoul, Korea
| | - J-E Yoo
- Department of Otorhinolaryngology, Yonsei University, College of Medicine, Seoul, Korea
| | - Y J Seo
- Department of Otorhinolaryngology, Yonsei University, WonJu College of Medicine, Wonju, Korea
| | - J Jung
- Department of Otorhinolaryngology, Yonsei University, College of Medicine, Seoul, Korea
| | - J Y Choi
- Department of Otorhinolaryngology, Yonsei University, College of Medicine, Seoul, Korea
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50
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Katz OL, Krantz ID, Noon SE. Interstitial deletion of 7q22.1q31.1 in a boy with structural brain abnormality, cardiac defect, developmental delay, and dysmorphic features. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2016; 172:92-101. [PMID: 27096924 DOI: 10.1002/ajmg.c.31485] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This report describes a male child with a history of poor feeding and swallowing problems, hypotonia, mild bilateral sensorineural hearing loss, cerebral cortical agenesis, cardiac defects, cyanotic episodes triggered by specific movement, dysmorphic features, and developmental delays. Analysis by CytoScan HD array identified a 12.1 Mb interstitial deletion of 7q22.1q31.1 (98,779,628-110,868,171). We present a comprehensive review of the literature surrounding intermediate 7q deletions that overlap with this child's deletion, and an analysis of candidate genes in the deleted region. © 2016 Wiley Periodicals, Inc.
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