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Zhao L, Yuan J, Wang G, Jing H, Huang C, Xu L, Xu X, Sun T, Chen W, Mao X, Li G. Chromosome-level genome and population genomics of the intermediate horseshoe bat ( Rhinolophus affinis) reveal the molecular basis of virus tolerance in Rhinolophus and echolocation call frequency variation. Zool Res 2024; 45:1147-1160. [PMID: 39257377 PMCID: PMC11491789 DOI: 10.24272/j.issn.2095-8137.2024.027] [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: 05/06/2024] [Accepted: 05/29/2024] [Indexed: 09/12/2024] Open
Abstract
Horseshoe bats (genus Rhinolophus, family Rhinolophidae) represent an important group within chiropteran phylogeny due to their distinctive traits, including constant high-frequency echolocation, rapid karyotype evolution, and unique immune system. Advances in evolutionary biology, supported by high-quality reference genomes and comprehensive whole-genome data, have significantly enhanced our understanding of species origins, speciation mechanisms, adaptive evolutionary processes, and phenotypic diversity. However, genomic research and understanding of the evolutionary patterns of Rhinolophus are severely constrained by limited data, with only a single published genome of R. ferrumequinum currently available. In this study, we constructed a high-quality chromosome-level reference genome for the intermediate horseshoe bat ( R. affinis). Comparative genomic analyses revealed potential genetic characteristics associated with virus tolerance in Rhinolophidae. Notably, we observed expansions in several immune-related gene families and identified various genes functionally associated with the SARS-CoV-2 signaling pathway, DNA repair, and apoptosis, which displayed signs of rapid evolution. In addition, we observed an expansion of the major histocompatibility complex class II (MHC-II) region and a higher copy number of the HLA- DQB2 gene in horseshoe bats compared to other chiropteran species. Based on whole-genome resequencing and population genomic analyses, we identified multiple candidate loci (e.g., GLI3) associated with variations in echolocation call frequency across R. affinis subspecies. This research not only expands our understanding of the genetic characteristics of the Rhinolophus genus but also establishes a valuable foundation for future research.
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Affiliation(s)
- Le Zhao
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
- QinLing-Bashan Mountains Bioresources Comprehensive Development C.I.C., School of Bioscience and Engineering, Shaanxi University of Technology, Hanzhong, Shaanxi 723001, China
| | - Jiaqing Yuan
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Guiqiang Wang
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Haohao Jing
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Chen Huang
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Lulu Xu
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Xiao Xu
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Ting Sun
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Wu Chen
- Guangzhou Zoo, Guangzhou, Guangdong 510070, China
| | - Xiuguang Mao
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China. E-mail:
| | - Gang Li
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
- Guangzhou Zoo, Guangzhou, Guangdong 510070, China. E-mail:
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Greve JN, Marquardt A, Heiringhoff R, Reindl T, Thiel C, Di Donato N, Taft MH, Manstein DJ. The non-muscle actinopathy-associated mutation E334Q in cytoskeletal γ-actin perturbs interaction of actin filaments with myosin and ADF/cofilin family proteins. eLife 2024; 12:RP93013. [PMID: 38446501 PMCID: PMC10942649 DOI: 10.7554/elife.93013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024] Open
Abstract
Various heterozygous cytoskeletal γ-actin mutations have been shown to cause Baraitser-Winter cerebrofrontofacial syndrome, non-syndromic hearing loss, or isolated eye coloboma. Here, we report the biochemical characterization of human cytoskeletal γ-actin carrying mutation E334Q, a mutation that leads to a hitherto unspecified non-muscle actinopathy. Following expression, purification, and removal of linker and thymosin β4 tag sequences, the p.E334Q monomers show normal integration into linear and branched actin filaments. The mutation does not affect thermal stability, actin filament nucleation, elongation, and turnover. Model building and normal mode analysis predict significant differences in the interaction of p.E334Q filaments with myosin motors and members of the ADF/cofilin family of actin-binding proteins. Assays probing the interactions of p.E334Q filaments with human class 2 and class 5 myosin motor constructs show significant reductions in sliding velocity and actin affinity. E334Q differentially affects cofilin-mediated actin dynamics by increasing the rate of cofilin-mediated de novo nucleation of actin filaments and decreasing the efficiency of cofilin-mediated filament severing. Thus, it is likely that p.E334Q-mediated changes in myosin motor activity, as well as filament turnover, contribute to the observed disease phenotype.
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Affiliation(s)
- Johannes N Greve
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
| | - Anja Marquardt
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
| | - Robin Heiringhoff
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
| | - Theresia Reindl
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
| | - Claudia Thiel
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
| | | | - Manuel H Taft
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
| | - Dietmar J Manstein
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for MedicalHannoverGermany
- Division for Structural Biochemistry, Hannover Medical SchoolHannoverGermany
- RESiST, Cluster of Excellence 2155, Hannover Medical SchoolHannoverGermany
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Feng Y, Hu S, Zhao S, Chen M. Recent advances in genetic etiology of non-syndromic deafness in children. Front Neurosci 2023; 17:1282663. [PMID: 37928735 PMCID: PMC10620706 DOI: 10.3389/fnins.2023.1282663] [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: 08/24/2023] [Accepted: 10/04/2023] [Indexed: 11/07/2023] Open
Abstract
Congenital auditory impairment is a prevalent anomaly observed in approximately 2-3 per 1,000 infants. The consequences associated with hearing loss among children encompass the decline of verbal communication, linguistic skills, educational progress, social integration, cognitive aptitude, and overall well-being. Approaches to reversing or preventing genetic hearing loss are limited. Patients with mild and moderate hearing loss can only use hearing aids, while those with severe hearing loss can only acquire speech and language through cochlear implants. Both environmental and genetic factors contribute to the occurrence of congenital hearing loss, and advancements in our understanding of the pathophysiology and molecular mechanisms underlying hearing loss, coupled with recent progress in genetic testing techniques, will facilitate the development of innovative approaches for treatment and screening. In this paper, the latest research progress in genetic etiology of non-syndromic deafness in children with the highest incidence is summarized in order to provide help for personalized diagnosis and treatment of deafness in children.
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Bai Y, Zhao F, Wu T, Chen F, Pang X. Actin polymerization and depolymerization in developing vertebrates. Front Physiol 2023; 14:1213668. [PMID: 37745245 PMCID: PMC10515290 DOI: 10.3389/fphys.2023.1213668] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/22/2023] [Indexed: 09/26/2023] Open
Abstract
Development is a complex process that occurs throughout the life cycle. F-actin, a major component of the cytoskeleton, is essential for the morphogenesis of tissues and organs during development. F-actin is formed by the polymerization of G-actin, and the dynamic balance of polymerization and depolymerization ensures proper cellular function. Disruption of this balance results in various abnormalities and defects or even embryonic lethality. Here, we reviewed recent findings on the structure of G-actin and F-actin and the polymerization of G-actin to F-actin. We also focused on the functions of actin isoforms and the underlying mechanisms of actin polymerization/depolymerization in cellular and organic morphogenesis during development. This information will extend our understanding of the role of actin polymerization in the physiologic or pathologic processes during development and may open new avenues for developing therapeutics for embryonic developmental abnormalities or tissue regeneration.
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Affiliation(s)
- Yang Bai
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Feng Zhao
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Tingting Wu
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Fangchun Chen
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Xiaoxiao Pang
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
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5
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Park J, Bird JE. The actin cytoskeleton in hair bundle development and hearing loss. Hear Res 2023; 436:108817. [PMID: 37300948 PMCID: PMC10408727 DOI: 10.1016/j.heares.2023.108817] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 05/18/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023]
Abstract
Inner ear hair cells assemble mechanosensitive hair bundles on their apical surface that transduce sounds and accelerations. Each hair bundle is comprised of ∼ 100 individual stereocilia that are arranged into rows of increasing height and width; their specific and precise architecture being necessary for mechanoelectrical transduction (MET). The actin cytoskeleton is fundamental to establishing this architecture, not only by forming the structural scaffold shaping each stereocilium, but also by composing rootlets and the cuticular plate that together provide a stable foundation supporting each stereocilium. In concert with the actin cytoskeleton, a large assortment of actin-binding proteins (ABPs) function to cross-link actin filaments into specific topologies, as well as control actin filament growth, severing, and capping. These processes are individually critical for sensory transduction and are all disrupted in hereditary forms of human hearing loss. In this review, we provide an overview of actin-based structures in the hair bundle and the molecules contributing to their assembly and functional properties. We also highlight recent advances in mechanisms driving stereocilia elongation and how these processes are tuned by MET.
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Affiliation(s)
- Jinho Park
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL 32610, United States; Myology Institute, University of Florida, Gainesville, FL 32610, United States
| | - Jonathan E Bird
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL 32610, United States; Myology Institute, University of Florida, Gainesville, FL 32610, United States.
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Aldè M, Cantarella G, Zanetti D, Pignataro L, La Mantia I, Maiolino L, Ferlito S, Di Mauro P, Cocuzza S, Lechien JR, Iannella G, Simon F, Maniaci A. Autosomal Dominant Non-Syndromic Hearing Loss (DFNA): A Comprehensive Narrative Review. Biomedicines 2023; 11:1616. [PMID: 37371710 DOI: 10.3390/biomedicines11061616] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 05/26/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Autosomal dominant non-syndromic hearing loss (HL) typically occurs when only one dominant allele within the disease gene is sufficient to express the phenotype. Therefore, most patients diagnosed with autosomal dominant non-syndromic HL have a hearing-impaired parent, although de novo mutations should be considered in all cases of negative family history. To date, more than 50 genes and 80 loci have been identified for autosomal dominant non-syndromic HL. DFNA22 (MYO6 gene), DFNA8/12 (TECTA gene), DFNA20/26 (ACTG1 gene), DFNA6/14/38 (WFS1 gene), DFNA15 (POU4F3 gene), DFNA2A (KCNQ4 gene), and DFNA10 (EYA4 gene) are some of the most common forms of autosomal dominant non-syndromic HL. The characteristics of autosomal dominant non-syndromic HL are heterogenous. However, in most cases, HL tends to be bilateral, post-lingual in onset (childhood to early adulthood), high-frequency (sloping audiometric configuration), progressive, and variable in severity (mild to profound degree). DFNA1 (DIAPH1 gene) and DFNA6/14/38 (WFS1 gene) are the most common forms of autosomal dominant non-syndromic HL affecting low frequencies, while DFNA16 (unknown gene) is characterized by fluctuating HL. A long audiological follow-up is of paramount importance to identify hearing threshold deteriorations early and ensure prompt treatment with hearing aids or cochlear implants.
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Affiliation(s)
- Mirko Aldè
- Department of Clinical Sciences and Community Health, University of Milan, 20090 Milan, Italy
- Department of Specialist Surgical Sciences, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20090 Milan, Italy
- Otology Study Group of the Young-Otolaryngologists of the International Federations of Oto-Rhino-Laryngological Societies (YO-IFOS), 75000 Paris, France
| | - Giovanna Cantarella
- Department of Clinical Sciences and Community Health, University of Milan, 20090 Milan, Italy
- Department of Specialist Surgical Sciences, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20090 Milan, Italy
| | - Diego Zanetti
- Department of Clinical Sciences and Community Health, University of Milan, 20090 Milan, Italy
- Department of Specialist Surgical Sciences, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20090 Milan, Italy
| | - Lorenzo Pignataro
- Department of Clinical Sciences and Community Health, University of Milan, 20090 Milan, Italy
- Department of Specialist Surgical Sciences, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20090 Milan, Italy
| | - Ignazio La Mantia
- Department of Medical, Surgical Sciences and Advanced Technologies G.F. Ingrassia, University of Catania, 95123 Catania, Italy
| | - Luigi Maiolino
- Department of Medical, Surgical Sciences and Advanced Technologies G.F. Ingrassia, University of Catania, 95123 Catania, Italy
| | - Salvatore Ferlito
- Department of Medical, Surgical Sciences and Advanced Technologies G.F. Ingrassia, University of Catania, 95123 Catania, Italy
| | - Paola Di Mauro
- Department of Medical, Surgical Sciences and Advanced Technologies G.F. Ingrassia, University of Catania, 95123 Catania, Italy
| | - Salvatore Cocuzza
- Department of Medical, Surgical Sciences and Advanced Technologies G.F. Ingrassia, University of Catania, 95123 Catania, Italy
| | - Jérôme René Lechien
- Otology Study Group of the Young-Otolaryngologists of the International Federations of Oto-Rhino-Laryngological Societies (YO-IFOS), 75000 Paris, France
| | - Giannicola Iannella
- Otology Study Group of the Young-Otolaryngologists of the International Federations of Oto-Rhino-Laryngological Societies (YO-IFOS), 75000 Paris, France
| | - Francois Simon
- Otology Study Group of the Young-Otolaryngologists of the International Federations of Oto-Rhino-Laryngological Societies (YO-IFOS), 75000 Paris, France
| | - Antonino Maniaci
- Otology Study Group of the Young-Otolaryngologists of the International Federations of Oto-Rhino-Laryngological Societies (YO-IFOS), 75000 Paris, France
- Department of Medical, Surgical Sciences and Advanced Technologies G.F. Ingrassia, University of Catania, 95123 Catania, Italy
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Bravo-Alonso I, Morin M, Arribas-Carreira L, Álvarez M, Pedrón-Giner C, Soletto L, Santolaria C, Ramón-Maiques S, Ugarte M, Rodríguez-Pombo P, Ariño J, Moreno-Pelayo MÁ, Pérez B. Pathogenic variants of the coenzyme A biosynthesis-associated enzyme phosphopantothenoylcysteine decarboxylase cause autosomal-recessive dilated cardiomyopathy. J Inherit Metab Dis 2023; 46:261-272. [PMID: 36564894 DOI: 10.1002/jimd.12584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/16/2022] [Accepted: 12/20/2022] [Indexed: 12/25/2022]
Abstract
Coenzyme A (CoA) is an essential cofactor involved in a range of metabolic pathways including the activation of long-chain fatty acids for catabolism. Cells synthesize CoA de novo from vitamin B5 (pantothenate) via a pathway strongly conserved across prokaryotes and eukaryotes. In humans, it involves five enzymatic steps catalyzed by four enzymes: pantothenate kinase (PANK [isoforms 1-4]), 4'-phosphopantothenoylcysteine synthetase (PPCS), phosphopantothenoylcysteine decarboxylase (PPCDC), and CoA synthase (COASY). To date, inborn errors of metabolism associated with all of these genes, except PPCDC, have been described, two related to neurodegeneration with brain iron accumulation (NBIA), and one associated with a cardiac phenotype. This paper reports another defect in this pathway (detected in two sisters), associated with a fatal cardiac phenotype, caused by biallelic variants (p.Thr53Pro and p.Ala95Val) of PPCDC. PPCDC enzyme (EC 4.1.1.36) catalyzes the decarboxylation of 4'-phosphopantothenoylcysteine to 4'-phosphopantetheine in CoA biosynthesis. The variants p.Thr53Pro and p.Ala95Val affect residues highly conserved across different species; p.Thr53Pro is involved in the binding of flavin mononucleotide, and p.Ala95Val is likely a destabilizing mutation. Patient-derived fibroblasts showed an absence of PPCDC protein, and nearly 50% reductions in CoA levels. The cells showed clear energy deficiency problems, with defects in mitochondrial respiration, and mostly glycolytic ATP synthesis. Functional studies performed in yeast suggest these mutations to be functionally relevant. In summary, this work describes a new, ultra-rare, severe inborn error of metabolism due to pathogenic variants of PPCDC.
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Affiliation(s)
- Irene Bravo-Alonso
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular, Universidad Autónoma de Madrid, CIBERER, IdiPAZ, Madrid, Spain
| | - Matías Morin
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III (CB06/07/0048; CIBERER-ISCIII), Madrid, Spain
| | - Laura Arribas-Carreira
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular, Universidad Autónoma de Madrid, CIBERER, IdiPAZ, Madrid, Spain
| | - Mar Álvarez
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular, Universidad Autónoma de Madrid, CIBERER, IdiPAZ, Madrid, Spain
| | - Consuelo Pedrón-Giner
- Sección de Gastroenterología y Nutrición, Hospital Infantil Universitario Niño Jesús, Madrid, Spain
| | - Lucia Soletto
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
| | - Carlos Santolaria
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | | | - Magdalena Ugarte
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular, Universidad Autónoma de Madrid, CIBERER, IdiPAZ, Madrid, Spain
| | - Pilar Rodríguez-Pombo
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular, Universidad Autónoma de Madrid, CIBERER, IdiPAZ, Madrid, Spain
| | - Joaquín Ariño
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Miguel Ángel Moreno-Pelayo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III (CB06/07/0048; CIBERER-ISCIII), Madrid, Spain
| | - Belén Pérez
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular, Universidad Autónoma de Madrid, CIBERER, IdiPAZ, Madrid, Spain
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Genetic etiology of non-syndromic hearing loss in Europe. Hum Genet 2022; 141:683-696. [PMID: 35044523 DOI: 10.1007/s00439-021-02425-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 12/20/2021] [Indexed: 12/17/2022]
Abstract
Hearing impairment not etiologically associated with clinical signs in other organs (non-syndromic) is genetically heterogeneous, so that over 120 genes are currently known to be involved. The frequency of mutations in each gene and the most frequent mutations vary throughout populations. Here we review the genetic etiology of non-syndromic hearing impairment (NSHI) in Europe. Over the years, epidemiological data were scarce because of the large number of involved genes, whose screening was not cost-effective until implementation of massively parallel DNA sequencing. In Europe, the most common form of autosomal recessive NSHI is DFNB1, which accounts for 11-57% of the cases. Mutations in STRC account for 16% of the recessive cases, and only a few more (MYO15A, MYO7A, LOXHD1, USH2A, TMPRSS3, CDH23, TMC1, OTOF, OTOA, SLC26A4, ADGRV1 and TECTA) have contributions higher than 2%. As regards autosomal-dominant NSHI, DFNA22 (MYO6) and DFNA8/12 (TECTA) represent the most common forms, accounting for 21% and 18% of elucidated cases, respectively. The contribution of ACTG1 and WFS1 drops to 9% in both cases, followed by POU4F3 (6.5%), MYO7A (5%), MYH14 and COL11A2 (4% each). Four additional genes contribute 2.5% each one (MITF, KCNQ4, EYA4, SOX10) and the remaining are residually represented. X-linked hearing loss and maternally-inherited NSHI have minor contributions in most countries. Further knowledge on the genetic epidemiology of NSHI in Europe needs a standardization of the experimental approaches and a stratification of the results according to clinical features, familial history and patterns of inheritance, to facilitate comparison between studies.
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De Novo ACTG1 Variant Expands the Phenotype and Genotype of Partial Deafness and Baraitser-Winter Syndrome. Int J Mol Sci 2022; 23:ijms23020692. [PMID: 35054877 PMCID: PMC8776155 DOI: 10.3390/ijms23020692] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/02/2022] [Accepted: 01/05/2022] [Indexed: 02/04/2023] Open
Abstract
Actin molecules are fundamental for embryonic structural and functional differentiation; γ-actin is specifically required for the maintenance and function of cytoskeletal structures in the ear, resulting in hearing. Baraitser–Winter Syndrome (B-WS, OMIM #243310, #614583) is a rare, multiple-anomaly genetic disorder caused by mutations in either cytoplasmically expressed actin gene, ACTB (β-actin) or ACTG1 (γ-actin). The resulting actinopathies cause characteristic cerebrofrontofacial and developmental traits, including progressive sensorineural deafness. Both ACTG1-related non-syndromic A20/A26 deafness and B-WS diagnoses are characterized by hypervariable penetrance in phenotype. Here, we identify a 28th patient worldwide carrying a mutated γ-actin ACTG1 allele, with mildly manifested cerebrofrontofacial B-WS traits, hypervariable penetrance of developmental traits and sensorineural hearing loss. This patient also displays brachycephaly and a complete absence of speech faculty, previously unreported for ACTG1-related B-WS or DFNA20/26 deafness, representing phenotypic expansion. The patient’s exome sequence analyses (ES) confirms a de novo ACTG1 variant previously unlinked to the pathology. Additional microarray analysis uncover no further mutational basis for dual molecular diagnosis in our patient. We conclude that γ-actin c.542C > T, p.Ala181Val is a dominant pathogenic variant, associated with mildly manifested facial and cerebral traits typical of B-WS, hypervariable penetrance of developmental traits and sensorineural deafness. We further posit and present argument and evidence suggesting ACTG1-related non-syndromic DFNA20/A26 deafness is a manifestation of undiagnosed ACTG1-related B-WS.
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DFNA20/26 and Other ACTG1-Associated Phenotypes: A Case Report and Review of the Literature. Audiol Res 2021; 11:582-593. [PMID: 34698053 PMCID: PMC8544197 DOI: 10.3390/audiolres11040052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/10/2021] [Accepted: 10/13/2021] [Indexed: 02/08/2023] Open
Abstract
Since the early 2000s, an ever-increasing subset of missense pathogenic variants in the ACTG1 gene has been associated with an autosomal-dominant, progressive, typically post-lingual non-syndromic hearing loss (NSHL) condition designed as DFNA20/26. ACTG1 gene encodes gamma actin, the predominant actin protein in the cytoskeleton of auditory hair cells; its normal expression and function are essential for the stereocilia maintenance. Different gain-of-function pathogenic variants of ACTG1 have been associated with two major phenotypes: DFNA20/26 and Baraitser-Winter syndrome, a multiple congenital anomaly disorder. Here, we report a novel ACTG1 variant [c.625G>A (p. Val209Met)] in an adult patient with moderate-severe NSHL characterized by a downsloping audiogram. The patient, who had a clinical history of slowly progressive NSHL and tinnitus, was referred to our laboratory for the analysis of a large panel of NSHL-associated genes by next generation sequencing. An extensive review of previously reported ACTG1 variants and their associated phenotypes was also performed.
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Cenni C, Mansard L, Blanchet C, Baux D, Vaché C, Baudoin C, Moclyn M, Faugère V, Mondain M, Jeziorski E, Roux AF, Willems M. When Familial Hearing Loss Means Genetic Heterogeneity: A Model Case Report. Diagnostics (Basel) 2021; 11:diagnostics11091636. [PMID: 34573976 PMCID: PMC8465614 DOI: 10.3390/diagnostics11091636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/04/2021] [Indexed: 11/29/2022] Open
Abstract
We describe a family with both hearing loss (HL) and thrombocytopenia, caused by pathogenic variants in three genes. The proband was a child with neonatal thrombocytopenia, childhood-onset HL, hyper-laxity and severe myopia. The child’s mother (and some of her relatives) presented with moderate thrombocytopenia and adulthood-onset HL. The child’s father (and some of his relatives) presented with adult-onset HL. An HL panel analysis, completed by whole exome sequencing, was performed in this complex family. We identified three pathogenic variants in three different genes: MYH9, MYO7A and ACTG1. The thrombocytopenia in the child and her mother is explained by the MYH9 variant. The post-lingual HL in the paternal branch is explained by the MYO7A variant, absent in the proband, while the congenital HL of the child is explained by a de novo ACTG1 variant. This family, in which HL segregates, illustrates that multiple genetic conditions coexist in individuals and make patient care more complex than expected.
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Affiliation(s)
- Camille Cenni
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, CHU Montpellier, Université de Montpellier, 34090 Montpellier, France;
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
| | - Luke Mansard
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
| | - Catherine Blanchet
- Service ORL, CHU Montpellier, Université de Montpellier, 34090 Montpellier, France; (C.B.); (M.M.)
- Centre National de Référence Maladies Rares “Affections Sensorielles Génétiques”, CHU Montpellier, Université de Montpellier, 34090 Montpellier, France
| | - David Baux
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
- INM, Université de Montpellier, INSERM U1298, 34090 Montpellier, France
| | - Christel Vaché
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
- INM, Université de Montpellier, INSERM U1298, 34090 Montpellier, France
| | - Corinne Baudoin
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
| | - Mélodie Moclyn
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
| | - Valérie Faugère
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
| | - Michel Mondain
- Service ORL, CHU Montpellier, Université de Montpellier, 34090 Montpellier, France; (C.B.); (M.M.)
| | - Eric Jeziorski
- Service de Pédiatrie Générale, Infectiologie et Immunologie Clinique, CHU Montpellier, Université de Montpellier, 34090 Montpellier, France;
| | - Anne-Françoise Roux
- Laboratoire de Génétique Moléculaire, CHU Montpellier, Université de Montpellier, 34090 Monpellier, France; (L.M.); (D.B.); (C.V.); (C.B.); (M.M.); (V.F.); (A.-F.R.)
- INM, Université de Montpellier, INSERM U1298, 34090 Montpellier, France
| | - Marjolaine Willems
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, CHU Montpellier, Université de Montpellier, 34090 Montpellier, France;
- Correspondence:
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12
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Van Heurck R, Carminho-Rodrigues MT, Ranza E, Stafuzza C, Quteineh L, Gehrig C, Hammar E, Guipponi M, Abramowicz M, Senn P, Guinand N, Cao-Van H, Paoloni-Giacobino A. Benefits of Exome Sequencing in Children with Suspected Isolated Hearing Loss. Genes (Basel) 2021; 12:genes12081277. [PMID: 34440452 PMCID: PMC8391342 DOI: 10.3390/genes12081277] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/03/2021] [Accepted: 08/18/2021] [Indexed: 12/12/2022] Open
Abstract
Purpose: Hearing loss is characterized by an extensive genetic heterogeneity and remains a common disorder in children. Molecular diagnosis is of particular benefit in children, and permits the early identification of clinically-unrecognized hearing loss syndromes, which permits effective clinical management and follow-up, including genetic counselling. Methods: We performed whole-exome sequencing with the analysis of a panel of 189 genes associated with hearing loss in a prospective cohort of 61 children and 9 adults presenting mainly with isolated hearing loss. Results: The overall diagnostic rate using exome sequencing was 47.2% (52.5% in children; 22% in adults). In children with confirmed molecular results, 17/32 (53.2%) showed autosomal recessive inheritance patterns, 14/32 (43.75%) showed an autosomal dominant condition, and one case had X-linked hearing loss. In adults, the two patients showed an autosomal dominant inheritance pattern. Among the 32 children, 17 (53.1%) had nonsyndromic hearing loss and 15 (46.7%) had syndromic hearing loss. One adult was diagnosed with syndromic hearing loss and one with nonsyndromic hearing loss. The most common causative genes were STRC (5 cases), GJB2 (3 cases), COL11A1 (3 cases), and ACTG1 (3 cases). Conclusions: Exome sequencing has a high diagnostic yield in children with hearing loss and can reveal a syndromic hearing loss form before other organs/systems become involved, allowing the surveillance of unrecognized present and/or future complications associated with these syndromes.
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Affiliation(s)
- Roxane Van Heurck
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Maria Teresa Carminho-Rodrigues
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Emmanuelle Ranza
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Caterina Stafuzza
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Lina Quteineh
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Corinne Gehrig
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Eva Hammar
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Michel Guipponi
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Marc Abramowicz
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Pascal Senn
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Nils Guinand
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Helene Cao-Van
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Ariane Paoloni-Giacobino
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
- Correspondence:
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13
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Delgado-Sequera A, Hidalgo-Figueroa M, Barrera-Conde M, Duran-Ruiz MC, Castro C, Fernández-Avilés C, de la Torre R, Sánchez-Gomar I, Pérez V, Geribaldi-Doldán N, Robledo P, Berrocoso E. Olfactory Neuroepithelium Cells from Cannabis Users Display Alterations to the Cytoskeleton and to Markers of Adhesion, Proliferation and Apoptosis. Mol Neurobiol 2020; 58:1695-1710. [PMID: 33237429 DOI: 10.1007/s12035-020-02205-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 11/09/2020] [Indexed: 12/26/2022]
Abstract
Cannabis is the third most commonly used psychoactive substance of abuse, yet it also receives considerable attention as a potential therapeutic drug. Therefore, it is essential to fully understand the actions of cannabis in the human brain. The olfactory neuroepithelium (ON) is a peripheral nervous tissue that represents an interesting surrogate model to study the effects of drugs in the brain, since it is closely related to the central nervous system, and sensory olfactory neurons are continually regenerated from populations of stem/progenitor cells that undergo neurogenesis throughout life. In this study, we used ON cells from chronic cannabis users and healthy control subjects to assess alterations in relevant cellular processes, and to identify changes in functional proteomic pathways due to cannabis consumption. The ON cells from cannabis users exhibited alterations in the expression of proteins that were related to the cytoskeleton, cell proliferation and cell death, as well as, changes in proteins implicated in cancer, gastrointestinal and neurodevelopmental pathologies. Subsequent studies showed cannabis provoked an increase in cell size and morphological alterations evident through β-Tubulin III staining, as well as, enhanced beta-actin expression and a decrease in the ability of ON cells to undergo cell attachment, suggesting abnormalities of the cytoskeleton and cell adhesion system. Furthermore, these cells proliferated more and underwent less cell death. Our results indicate that cannabis may alter key processes of the developing brain, some of which are similar to those reported in mental disorders like DiGeorge syndrome, schizophrenia and bipolar disorder.
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Affiliation(s)
- Alejandra Delgado-Sequera
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Campus Universitario Río San Pedro s/n, 11510, Puerto Real, Cadiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
| | - María Hidalgo-Figueroa
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Campus Universitario Río San Pedro s/n, 11510, Puerto Real, Cadiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Marta Barrera-Conde
- Integrative Pharmacology and Systems Neuroscience, Neurosciences Research Programme, IMIM-Hospital del Mar Research Institute, PRBB, Calle Dr. Aiguader 88, 08003, Barcelona, Spain
- Department of Experimental and Health Sciences, University Pompeu Fabra, Barcelona, Spain
| | - Mª Carmen Duran-Ruiz
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Biomedicine, Biotechnology and Public Health Department, University of Cádiz, Cádiz, Spain
| | - Carmen Castro
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Biomedicine, Biotechnology and Public Health Department, University of Cádiz, Cádiz, Spain
| | | | - Rafael de la Torre
- Integrative Pharmacology and Systems Neuroscience, Neurosciences Research Programme, IMIM-Hospital del Mar Research Institute, PRBB, Calle Dr. Aiguader 88, 08003, Barcelona, Spain
- Biomedicine, Biotechnology and Public Health Department, University of Cádiz, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
| | - Ismael Sánchez-Gomar
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Biomedicine, Biotechnology and Public Health Department, University of Cádiz, Cádiz, Spain
| | - Víctor Pérez
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Neuropsychiatry and Addictions Institute (INAD) of Parc de Salut Mar, Barcelona, Spain
| | - Noelia Geribaldi-Doldán
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Department of Human Anatomy and Embriology, University of Cádiz, Cádiz, Spain
| | - Patricia Robledo
- Integrative Pharmacology and Systems Neuroscience, Neurosciences Research Programme, IMIM-Hospital del Mar Research Institute, PRBB, Calle Dr. Aiguader 88, 08003, Barcelona, Spain.
- Department of Experimental and Health Sciences, University Pompeu Fabra, Barcelona, Spain.
| | - Esther Berrocoso
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Campus Universitario Río San Pedro s/n, 11510, Puerto Real, Cadiz, Spain.
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain.
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14
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Parker F, Baboolal TG, Peckham M. Actin Mutations and Their Role in Disease. Int J Mol Sci 2020; 21:ijms21093371. [PMID: 32397632 PMCID: PMC7247010 DOI: 10.3390/ijms21093371] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 12/15/2022] Open
Abstract
Actin is a widely expressed protein found in almost all eukaryotic cells. In humans, there are six different genes, which encode specific actin isoforms. Disease-causing mutations have been described for each of these, most of which are missense. Analysis of the position of the resulting mutated residues in the protein reveals mutational hotspots. Many of these occur in regions important for actin polymerization. We briefly discuss the challenges in characterizing the effects of these actin mutations, with a focus on cardiac actin mutations.
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15
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Miyajima H, Moteki H, Day T, Nishio SY, Murata T, Ikezono T, Takeda H, Abe S, Iwasaki S, Takahashi M, Naito Y, Yamazaki H, Kanda Y, Kitajiri SI, Usami SI. Novel ACTG1 mutations in patients identified by massively parallel DNA sequencing cause progressive hearing loss. Sci Rep 2020; 10:7056. [PMID: 32341388 PMCID: PMC7184572 DOI: 10.1038/s41598-020-63690-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 04/03/2020] [Indexed: 11/09/2022] Open
Abstract
Human ACTG1 mutations are associated with high-frequency hearing loss, and patients with mutations in this gene are good candidates for electric acoustic stimulation. To better understand the genetic etiology of hearing loss cases, massively parallel DNA sequencing was performed on 7,048 unrelated Japanese hearing loss probands. Among 1,336 autosomal dominant hearing loss patients, we identified 15 probands (1.1%) with 13 potentially pathogenic ACTG1 variants. Six variants were novel and seven were previously reported. We collected and analyzed the detailed clinical features of these patients. The average progression rate of hearing deterioration in pure-tone average for four frequencies was 1.7 dB/year from 0 to 50 years age, and all individuals over 60 years of age had severe hearing loss. To better understand the underlying disease-causing mechanism, intracellular localization of wild-type and mutant gamma-actins were examined using the NIH/3T3 fibroblast cell line. ACTG1 mutants p.I34M p.M82I, p.K118M and p.I165V formed small aggregates while p.R37H, p.G48R, p.E241K and p.H275Y mutant gamma-actins were distributed in a similar manner to the WT. From these results, we believe that some part of the pathogenesis of ACTG1 mutations may be driven by the inability of defective gamma-actin to be polymerized into F-actin.
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Affiliation(s)
- Hiroki Miyajima
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hideaki Moteki
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Timothy Day
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | | | - Tetsuo Ikezono
- Department of Otorhinolaryngology, Saitama Medical University, Irima, Japan
| | - Hidehiko Takeda
- Department of Otorhinolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Satoko Abe
- Department of Otorhinolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Satoshi Iwasaki
- Department of Otorhinolaryngology, International University of Health and Welfare, Mita Hospital, Tokyo, Japan
| | - Masahiro Takahashi
- Department of Otorhinolaryngology, International University of Health and Welfare, Mita Hospital, Tokyo, Japan
| | - Yasushi Naito
- Departments of Otolaryngology - Head and Neck Surgery, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Hiroshi Yamazaki
- Department of Otolaryngology, Osaka Red Cross Hospital, Osaka, Japan
| | - Yukihiko Kanda
- Kanda ENT Clinic, Nagasaki Bell Hearing Center, Nagasaki, Japan
| | - 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. .,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan.
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16
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Witjes L, Van Troys M, Verhasselt B, Ampe C. Prevalence of Cytoplasmic Actin Mutations in Diffuse Large B-Cell Lymphoma and Multiple Myeloma: A Functional Assessment Based on Actin Three-Dimensional Structures. Int J Mol Sci 2020; 21:ijms21093093. [PMID: 32349449 PMCID: PMC7247664 DOI: 10.3390/ijms21093093] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 04/24/2020] [Accepted: 04/26/2020] [Indexed: 02/06/2023] Open
Abstract
Mutations in actins have been linked to several developmental diseases. Their occurrence across different cancers has, however, not been investigated. Using the cBioPortal database we show that human actins are infrequently mutated in patient samples of various cancers types. Nevertheless, ranking these studies by mutational frequency suggest that some have a higher percentage of patients with ACTB and ACTG1 mutations. Within studies on hematological cancers, mutations in ACTB and ACTG1 are associated with lymphoid cancers since none have currently been reported in myeloid cancers. Within the different types of lymphoid cancers ACTB mutations are most frequent in diffuse large B-cell lymphoma (DLBCL) and ACTG1 mutations in multiple myeloma. We mapped the ACTB and ACTG1 mutations found in these two cancer types on the 3D-structure of actin showing they are in regions important for actin polymer formation or binding to myosin. The potential effects of the mutations on actin properties imply that mutations in cytoplasmic actins deserve dedicated research in DLBCL and multiple myeloma.
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Affiliation(s)
- Laura Witjes
- Department of Biomolecular Medicine, Ghent University, Albert Baertsoenkaai 3, B-9000 Ghent, Belgium
- Department of Diagnostic Sciences, Ghent University Hospital, Ghent University, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Marleen Van Troys
- Department of Biomolecular Medicine, Ghent University, Albert Baertsoenkaai 3, B-9000 Ghent, Belgium
| | - Bruno Verhasselt
- Department of Diagnostic Sciences, Ghent University Hospital, Ghent University, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Christophe Ampe
- Department of Biomolecular Medicine, Ghent University, Albert Baertsoenkaai 3, B-9000 Ghent, Belgium
- Correspondence:
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17
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Morín M, Borreguero L, Booth KT, Lachgar M, Huygen P, Villamar M, Mayo F, Barrio LC, Santos Serrão de Castro L, Morales C, Del Castillo I, Arellano B, Tellería D, Smith RJH, Azaiez H, Moreno Pelayo MA. Insights into the pathophysiology of DFNA10 hearing loss associated with novel EYA4 variants. Sci Rep 2020; 10:6213. [PMID: 32277154 PMCID: PMC7148344 DOI: 10.1038/s41598-020-63256-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/27/2020] [Indexed: 12/13/2022] Open
Abstract
The mutational spectrum of many genes and their contribution to the global prevalence of hereditary hearing loss is still widely unknown. In this study, we have performed the mutational screening of EYA4 gene by DHLPC and NGS in a large cohort of 531 unrelated Spanish probands and one Australian family with autosomal dominant non-syndromic hearing loss (ADNSHL). In total, 9 novel EYA4 variants have been identified, 3 in the EYA4 variable region (c.160G > T; p.Glu54*, c.781del; p.Thr261Argfs*34 and c.1078C > A; p.Pro360Thr) and 6 in the EYA-HR domain (c.1107G > T; p.Glu369Asp, c.1122G > T; p.Trp374Cys, c.1281G > A; p.Glu427Glu, c.1282-1G > A, c.1601C > G; p.S534* and an heterozygous copy number loss encompassing exons 15 to 17). The contribution of EYA4 mutations to ADNSHL in Spain is, therefore, very limited (~1.5%, 8/531). The pathophysiology of some of these novel variants has been explored. Transient expression of the c-myc-tagged EYA4 mutants in mammalian COS7 cells revealed absence of expression of the p.S534* mutant, consistent with a model of haploinsufficiency reported for all previously described EYA4 truncating mutations. However, normal expression pattern and translocation to the nucleus were observed for the p.Glu369Asp mutant in presence of SIX1. Complementary in silico analysis suggested that c.1107G > T (p.Glu369Asp), c.1281G > A (p.Glu427Glu) and c.1282-1G > A variants alter normal splicing. Minigene assays in NIH3T3 cells further confirmed that all 3 variants caused exon skipping resulting in frameshifts that lead to premature stop codons. Our study reports the first likely pathogenic synonymous variant linked to DFNA10 and provide further evidence for haploinsufficiency as the common underlying disease-causing mechanism for DFNA10-related hearing loss.
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Affiliation(s)
- Matias Morín
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Lucía Borreguero
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Kevin T Booth
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head & Surgery, University of Iowa, Iowa City, Iowa, 52242, USA.,Harvard Medical School, Department of Neurobiology, Boston, Massachusetts, 02115, USA
| | - María Lachgar
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Patrick Huygen
- Department of Otorhinolaryngology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands
| | - Manuela Villamar
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Fernando Mayo
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Luis Carlos Barrio
- Departamento de Investigación, Ramón y Cajal Institute of Health Research (IRYCIS), Unidad de Neurología Experimental, 28034, Madrid, Spain
| | - Luciana Santos Serrão de Castro
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Carmelo Morales
- Servicio de Otorrinolaringología, Hospital Universitario Marqués de Valdecilla, 39008, Santander, Spain
| | - Ignacio Del Castillo
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Beatriz Arellano
- Servicio de Otorrinolaringología, Hospital Universitario Puerta de Hierro, Majadahonda, 28922, Madrid, Spain
| | - Dolores Tellería
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head & Surgery, University of Iowa, Iowa City, Iowa, 52242, USA
| | - Hela Azaiez
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head & Surgery, University of Iowa, Iowa City, Iowa, 52242, USA
| | - M A Moreno Pelayo
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain.
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18
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Sun Y, Liang W, Shen W, Feng H, Chen J, Si Z, Hu Y, Zhang T. G65V Substitution in Actin Disturbs Polymerization Leading to Inhibited Cell Elongation in Cotton. FRONTIERS IN PLANT SCIENCE 2019; 10:1486. [PMID: 31803216 PMCID: PMC6873290 DOI: 10.3389/fpls.2019.01486] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 10/25/2019] [Indexed: 06/10/2023]
Abstract
The importance of the actin cytoskeleton for proper cell development has been well established in a variety of organisms. Actin protein sequences are highly conserved, and each amino acid residue may be essential for its function. In this study, we report the isolation and characterization of GhLi 1 from an upland cotton mutant Ligon lintless-1 (Li1), which harbors the G65V substitution in its encoded actin protein. Li1 mutants exhibit pleiotropic malformed phenotypes, including dwarf plants, distorted organs, and extremely shortened fibers. Cytological analysis showed that the actin cytoskeleton was disorganized and the abundance of F-actin was decreased in the Li1 cells. Vesicles were aggregated into patches, and excessive cellulose synthase complexes were inserted into the plasma membrane during the secondary cell wall biosynthesis stage, which dramatically affected the morphology of the Li1 cells. Molecular model prediction suggested that the G65V substitution may affect the three-bodied G-actin interaction during F-actin assembly. Biochemical assays demonstrated that the recombinant GhLi1 protein disturbs actin dynamics by inhibiting the nucleation and elongation processes. Therefore, our findings demonstrate that the G65V substitution in actin had dominant-negative effects on cell elongation, by disturbing actin polymerization and actin cytoskeleton-based biological processes such as intracellular transportation.
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Affiliation(s)
- Yongwang Sun
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Wenhua Liang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Weijuan Shen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Hao Feng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Jiedan Chen
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Zhanfeng Si
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Yan Hu
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Tianzhen Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
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19
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Liu WH, Chang PY, Chang SC, Lu JJ, Wu CM. Mutation screening in non-syndromic hearing loss patients with cochlear implantation by massive parallel sequencing in Taiwan. PLoS One 2019; 14:e0211261. [PMID: 30682115 PMCID: PMC6347456 DOI: 10.1371/journal.pone.0211261] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 01/10/2019] [Indexed: 01/05/2023] Open
Abstract
Objectives To explore the molecular epidemiology of rare deafness genes in Taiwanese sensorineural hearing impairment (SNHI) patients with cochlear implantation (CI) by performing massive parallel sequencing (MPS) and correlating genetic factors and CI outcomes. Methods We enrolled 41 Taiwanese non-syndromic deafness patients with CI that lacked known mutations in common deafness genes. All probands were screened by a targeted exon amplification method that used massively parallel sequencing to screen a customized panel that included 40 relatively rare non-syndromic deafness genes. Results Thirteen candidate variants in nine relatively rare deafness genes (MYO15A, TMC1, MYH14, MYO3A, ACTG1, COL11A2, DSPP, GRHL2, and WFS1) were identified in 24.4% (10/41) of the non-syndromic deafness probands with CI. According to the ACMG Standards and Guidelines, five variants in MYO15A and ACTG1 were classified as likely pathogenic variants. Two of three multi-generational pedigrees exhibiting deafness were analyzed for the segregation of the disorder with the possible disease-causing variants. Patients with variants detected in most of the identified variant-bearing genes showed relatively good CI outcomes. Conclusions We successfully identified candidate variants in partially deaf Taiwanese probands who lacked the known mutations in common deafness genes. Comparing the progress of hearing rehabilitation in CI patients with their apparent causative variants and the expression profiles of their altered genes allowed us to speculate on how alterations in specific gene sets may influence outcomes in hearing rehabilitation after CI.
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Affiliation(s)
- Wei-Hsiu Liu
- Department of Laboratory Medicine, Chang-Gung Memorial Hospital, Linkou Branch, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
- Department of Otolaryngology—Head and Neck Surgery, Chang-Gung Memorial Hospital, Linkou Branch, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
| | - Pi-Yueh Chang
- Department of Medical Biotechnology and Laboratory Science, Chang-Gung University, Taoyuan, Taiwan
- Department of Medical Research, Chang-Gung Memorial Hospital and Graduate of Institute of Clinical Medical Science, Chang Gung University, Taoyuan, Taiwan
| | - Shih-Cheng Chang
- Department of Medical Biotechnology and Laboratory Science, Chang-Gung University, Taoyuan, Taiwan
- Department of Medical Research, Chang-Gung Memorial Hospital and Graduate of Institute of Clinical Medical Science, Chang Gung University, Taoyuan, Taiwan
| | - Jang-Jih Lu
- Department of Medical Biotechnology and Laboratory Science, Chang-Gung University, Taoyuan, Taiwan
- Department of Medical Research, Chang-Gung Memorial Hospital and Graduate of Institute of Clinical Medical Science, Chang Gung University, Taoyuan, Taiwan
- * E-mail: (CMW); (J-JL)
| | - Che-Ming Wu
- Department of Otolaryngology—Head and Neck Surgery, Chang-Gung Memorial Hospital, Linkou Branch, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
- * E-mail: (CMW); (J-JL)
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20
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Vélez-Ortega AC, Frolenkov GI. Building and repairing the stereocilia cytoskeleton in mammalian auditory hair cells. Hear Res 2019; 376:47-57. [PMID: 30638948 DOI: 10.1016/j.heares.2018.12.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/19/2018] [Accepted: 12/28/2018] [Indexed: 10/27/2022]
Abstract
Despite all recent achievements in identification of the molecules that are essential for the structure and mechanosensory function of stereocilia bundles in the auditory hair cells of mammalian species, we still have only a rudimentary understanding of the mechanisms of stereocilia formation, maintenance, and repair. Important molecular differences distinguishing mammalian auditory hair cells from hair cells of other types and species have been recently revealed. In addition, we are beginning to solve the puzzle of the apparent life-long stability of the stereocilia bundles in these cells. New data link the stability of the cytoskeleton in the mammalian auditory stereocilia with the normal activity of mechanotransduction channels. These data suggest new ideas on how a terminally-differentiated non-regenerating hair cell in the mammalian cochlea may repair and tune its stereocilia bundle throughout the life span of the organism.
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Affiliation(s)
- A Catalina Vélez-Ortega
- Department of Physiology, University of Kentucky, 800 Rose St., Lexington, KY, 40536-0298, USA.
| | - Gregory I Frolenkov
- Department of Physiology, University of Kentucky, 800 Rose St., Lexington, KY, 40536-0298, USA.
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21
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Yang T, Guo L, Wang L, Yu X. Diagnosis, Intervention, and Prevention of Genetic Hearing Loss. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1130:73-92. [PMID: 30915702 DOI: 10.1007/978-981-13-6123-4_5] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is estimated that at least 50% of congenital or childhood hearing loss is attributable to genetic causes. In non-syndromic hearing loss, which accounts for 70% of genetic hearing loss, approximately 80% of cases are autosomal recessive, 15% autosomal dominant, and 1-2% mitochondrial or X-linked. In addition, 30% of genetic hearing loss is syndromic. The genetic causes of hearing loss are highly heterogeneous. So far, more than 140 deafness-related genes have been discovered. Studies on those genes tremendously increased our understanding of the inner ear functions at the molecular level. It also offers important information for the patients and allows personalized and accurate genetic counseling. In many cases, genetic diagnosis of hearing loss can help to avoid unnecessary and costly clinical testing, offer prognostic information, and guide future medical management. On the other hand, a variety of gene therapeutic approaches have been developed aiming to relieve or converse the hearing loss due to genetic causes. Prevention of genetic hearing loss is feasible through prepregnancy and prenatal genetic diagnosis and counseling.
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Affiliation(s)
- Tao Yang
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China. .,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China. .,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China.
| | - Luo Guo
- Key Laboratory of Hearing Medicine of NHFPC, ENT Institute and Otorhinolaryngology Department, Shanghai Engineering Research Centre of Cochlear Implant, Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China
| | - Longhao Wang
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Xiaoyu Yu
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
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22
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Gao B, Li S, Tan Z, Ma L, Liu J. ACTG1 and TLR3 are biomarkers for alcohol-associated hepatocellular carcinoma. Oncol Lett 2018; 17:1714-1722. [PMID: 30675230 PMCID: PMC6341811 DOI: 10.3892/ol.2018.9757] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 10/15/2018] [Indexed: 12/14/2022] Open
Abstract
Alcohol consumption is a risk factor for the development of hepatocellular carcinoma (HCC); however, the association between alcohol and HCC remains unknown. The present study aimed to identify key genes related to alcohol-associated HCC to improve the current understanding of the pathology of this disease. Alcohol-associated and non-alcohol-associated HCC samples in the GSE50579 dataset of the Gene Omnibus Database were analyzed to investigate altered gene expression. Integrated bioinformatics methods were employed to clarify the biological functions of the differentially expressed genes (DEGs), including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interactions (PPIs). The present study reported that candidate biomarker micro (mi)RNAs via TargetScan Human 7.1. DEGs and their associated miRNAs (according to bioinformatics analysis) were validated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Additionally, 284 EGs from the GSE50579 dataset were revealed. In GO term analysis, DEGs were closely associated with the ‘regulation of nucleic acid metabolism’. KEGG pathway analysis indicated that the DEGs were tightly engaged in the ‘VEGF and VEGF receptor signaling network’, ‘proteoglycan syndecan-mediated signaling events’, ‘erbB receptor signaling’ and ‘β1 integrin cell surface interactions’. According to the results of PPI and heat map analysis, the main hub genes were centrin 3 (CETN3), Toll-like receptor 3 (TLR3), receptor tyrosine-protein kinase (ERBB4), heat shock protein family member 8, actin γ1 (ACTG1) and α-smooth muscle actin. it was demonstrated that the ACTG1, TLR3, miR-6819-3p and miRΝΑ (miR)-6877-3P had undefined associations. Furthermore, RT-qPCR analysis revealed that miR-6819-3p and miR-6877-3P may enhance the expression levels of ACTG1 and inhibit the expression levels of TLR3 in alcohol-associated HCC tissues. TLR3 and ACTG1 were proposed as potential biomarkers of alcohol-associated HCC. Investigation into the regulatory functions of miR-6819-3p and miR-6877-3P may provide novel insights into the treatment of alcohol-associated HCC.
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Affiliation(s)
- Bing Gao
- School of Pharmacy, Qingdao University, Qingdao, Shandong 266021, P.R. China.,School of Basic Medicine, Qingdao University, Qingdao, Shandong 266021, P.R. China
| | - Shicheng Li
- Department of Thoracic Surgery, Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, P.R. China
| | - Zhen Tan
- Department of Hepatopancreatobiliary Surgery, Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, P.R. China
| | - Leina Ma
- Cancer Institute, Affiliated Hospital of Qingdao University, Qingdao, Shandong 266021, P.R. China.,Qingdao Cancer Institute, Qingdao, Shandong 266021, P.R. China
| | - Jia Liu
- School of Pharmacy, Qingdao University, Qingdao, Shandong 266021, P.R. China
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23
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Cabanillas R, Diñeiro M, Cifuentes GA, Castillo D, Pruneda PC, Álvarez R, Sánchez-Durán N, Capín R, Plasencia A, Viejo-Díaz M, García-González N, Hernando I, Llorente JL, Repáraz-Andrade A, Torreira-Banzas C, Rosell J, Govea N, Gómez-Martínez JR, Núñez-Batalla F, Garrote JA, Mazón-Gutiérrez Á, Costales M, Isidoro-García M, García-Berrocal B, Ordóñez GR, Cadiñanos J. Comprehensive genomic diagnosis of non-syndromic and syndromic hereditary hearing loss in Spanish patients. BMC Med Genomics 2018; 11:58. [PMID: 29986705 PMCID: PMC6038346 DOI: 10.1186/s12920-018-0375-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/14/2018] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Sensorineural hearing loss (SNHL) is the most common sensory impairment. Comprehensive next-generation sequencing (NGS) has become the standard for the etiological diagnosis of early-onset SNHL. However, accurate selection of target genomic regions (gene panel/exome/genome), analytical performance and variant interpretation remain relevant difficulties for its clinical implementation. METHODS We developed a novel NGS panel with 199 genes associated with non-syndromic and/or syndromic SNHL. We evaluated the analytical sensitivity and specificity of the panel on 1624 known single nucleotide variants (SNVs) and indels on a mixture of genomic DNA from 10 previously characterized lymphoblastoid cell lines, and analyzed 50 Spanish patients with presumed hereditary SNHL not caused by GJB2/GJB6, OTOF nor MT-RNR1 mutations. RESULTS The analytical sensitivity of the test to detect SNVs and indels on the DNA mixture from the cell lines was > 99.5%, with a specificity > 99.9%. The diagnostic yield on the SNHL patients was 42% (21/50): 47.6% (10/21) with autosomal recessive inheritance pattern (BSND, CDH23, MYO15A, STRC [n = 2], USH2A [n = 3], RDX, SLC26A4); 38.1% (8/21) autosomal dominant (ACTG1 [n = 3; 2 de novo], CHD7, GATA3 [de novo], MITF, P2RX2, SOX10), and 14.3% (3/21) X-linked (COL4A5 [de novo], POU3F4, PRPS1). 46.9% of causative variants (15/32) were not in the databases. 28.6% of genetically diagnosed cases (6/21) had previously undetected syndromes (Barakat, Usher type 2A [n = 3] and Waardenburg [n = 2]). 19% of genetic diagnoses (4/21) were attributable to large deletions/duplications (STRC deletion [n = 2]; partial CDH23 duplication; RDX exon 2 deletion). CONCLUSIONS In the era of precision medicine, obtaining an etiologic diagnosis of SNHL is imperative. Here, we contribute to show that, with the right methodology, NGS can be transferred to the clinical practice, boosting the yield of SNHL genetic diagnosis to 50-60% (including GJB2/GJB6 alterations), improving diagnostic/prognostic accuracy, refining genetic and reproductive counseling and revealing clinically relevant undiagnosed syndromes.
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Affiliation(s)
- Rubén Cabanillas
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain.
| | - Marta Diñeiro
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Guadalupe A Cifuentes
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - David Castillo
- Disease Research And Medicine (DREAMgenics) S. L., Oviedo, Spain
| | | | - Rebeca Álvarez
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Noelia Sánchez-Durán
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Raquel Capín
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Ana Plasencia
- Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | | | - Inés Hernando
- Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | | | | | - Jordi Rosell
- Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | - Nancy Govea
- Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | | | | | | | | | - María Costales
- Hospital Universitario Central de Asturias, Oviedo, Spain.,Hospital Universitario Marqués de Valdecilla, Santander, Spain
| | | | | | | | - Juan Cadiñanos
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain.
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24
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Wang L, Yan D, Qin L, Li T, Liu H, Li W, Mittal R, Yong F, Chapagain P, Liao S, Liu X. Amino acid 118 in the Deafness Causing (DFNA20/26) ACTG1 gene is a Mutational Hot Spot. GENE REPORTS 2018; 11:264-269. [PMID: 30599039 DOI: 10.1016/j.genrep.2018.04.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Background Hearing loss is an economically and socially important cause of human morbidity, affecting 360 million people (over 5% of the world's population), of whom 32 million are children. Of the estimated minimum of 50% of hereditary hearing loss, non-syndromic hearing loss (NSHL) accounts for more than 70%. The autosomal dominant non-syndromic hearing loss (ADNSHL) is highly heterogeneous. To date, 67 ADNSHL loci (DFNA1-67) have been mapped; however, only 35 causative genes have been cloned since 1997 (http://hereditaryhearingloss.org/). Methods To identify the genetic basis of hereditary hearing loss in a Chinese family with ADNSHL, we undertook a targeted sequencing of 180 genes using a custom capture panel (MiamiOtoGenes). Results The onset of hearing loss in the family occurred between the ages of 15 and 18 years. Hearing loss was bilateral, started in the high frequency and progressed to lower frequencies. The c.353A>T (K118M) in the AC TG1 gene was identified by panel and was confirmed by Sanger sequencing and was present in all affected family members. So far, five of the 23 DFNA20/26 families worldwide have been found to carry mutation involving the residue K118. Conclusions This is the first report of K118M mutation in the ACTG1 gene causing hearing loss in the Chinese population. The present data are in line with previous evidence to suggest that codon K118 of ACTG1 may represent a mutational hot spot that justifies a mutation screen for diagnostic purpose in the genetically heterogeneous group of DFNA20/26.
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Affiliation(s)
- Li Wang
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China.,Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, USA
| | - Litao Qin
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Tao Li
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Hongjian Liu
- Department of Otorhinolaryngology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Wan Li
- Department of Otorhinolaryngology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Rahul Mittal
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Feng Yong
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China
| | - Prem Chapagain
- Department of Physics, Florida International University, Miami, Florida.,Biomolecular Sciences Institute, Florida International University, Miami, Florida
| | - Shixiu Liao
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Xuezhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, USA
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25
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Lee CG, Jang J, Jin HS. A novel missense mutation in the ACTG1 gene in a family with congenital autosomal dominant deafness: A case report. Mol Med Rep 2018; 17:7611-7617. [PMID: 29620237 PMCID: PMC5983957 DOI: 10.3892/mmr.2018.8837] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 05/12/2017] [Indexed: 12/20/2022] Open
Abstract
The ACTG1 gene encodes the cytoskeletal protein γ-actin, which functions in non-muscle cells and is abundant in the auditory hair cells of the cochlea. Autosomal dominant missense mutations in ACTG1 are associated with DFNA20/26, a disorder that is typically characterized by post-lingual progressive hearing loss. To date, 17 missense mutations in ACTG1 have been reported in 20 families with DFNA20/26. The present study described a small family with autosomal dominant nonsyndromic hearing loss. A novel heterozygous missense mutation, c.94C>T (p.Pro32Ser), in ACTG1 was identified using the TruSight One sequencing panel. Notably, congenital hearing loss in our proband was identified by newborn hearing screening at birth. In silico predictions of protein structure and function indicate that the p.Pro32Ser mutation may result in conformational changes in γ-actin. The present study expands the understanding of the phenotypic effects of heterozygous missense mutations in the ACTG1 gene. In specific, the present results emphasize that mutations in ACTG1 result in a diverse spectrum of onset ages, including congenital in addition to post-lingual onset.
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Affiliation(s)
- Cha Gon Lee
- Division of Child Neurology, Department of Pediatrics, Nowon Eulji Medical Center, Eulji University, Seoul 01830, Republic of Korea
| | - Jahyeon Jang
- Green Cross Genome, Yongin, Gyeonggi 16924, Republic of Korea
| | - Hyun-Seok Jin
- Department of Biomedical Laboratory Science, College of Life and Health Sciences, Hoseo University, Asan, Chungcheongnam 31499, Republic of Korea
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26
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Mittal R, Patel AP, Nguyen D, Pan DR, Jhaveri VM, Rudman JR, Dharmaraja A, Yan D, Feng Y, Chapagain P, Lee DJ, Blanton SH, Liu XZ. Genetic basis of hearing loss in Spanish, Hispanic and Latino populations. Gene 2018; 647:297-305. [PMID: 29331482 PMCID: PMC5806531 DOI: 10.1016/j.gene.2018.01.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 01/02/2018] [Accepted: 01/06/2018] [Indexed: 12/13/2022]
Abstract
Hearing loss (HL) is the most common neurosensory disorder affecting humans. The screening, prevention and treatment of HL require a better understanding of the underlying molecular mechanisms. Genetic predisposition is one of the most common factors that leads to HL. Most HL studies include few Spanish, Hispanic and Latino participants, leaving a critical gap in our understanding about the prevalence, impact, unmet health care needs, and genetic factors associated with hearing impairment among Spanish, Hispanic and Latino populations. The few studies which have been performed show that the gene variants commonly associated with HL in non-Spanish and non-Hispanic populations are infrequently responsible for hearing impairment in Spanish as well as Hispanic and Latino populations (hereafter referred to as Hispanic). To design effective screening tools to detect HL in Spanish and Hispanic populations, studies must be conducted to determine the gene variants that are most commonly associated with hearing impairment in this racial/ethnic group. In this review article, we summarize gene variants and loci associated with HL in Spanish and Hispanic populations. Identifying new genetic variants associated with HL in Spanish and Hispanic populations will pave the way to develop effective screening tools and therapeutic strategies for HL.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Amit P Patel
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Desiree Nguyen
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Debbie R Pan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Vasanti M Jhaveri
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jason R Rudman
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Arjuna Dharmaraja
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Yong Feng
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China
| | - Prem Chapagain
- Department of Physics and Biomolecular Sciences Institute, Florida International University, Miami, FL, USA
| | - David J Lee
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Susan H Blanton
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA; Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China; Tsinghua University School of Medicine, Beijing 10084, China; Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Nishio SY, Usami SI. Outcomes of cochlear implantation for the patients with specific genetic etiologies: a systematic literature review. Acta Otolaryngol 2017; 137:730-742. [PMID: 28498079 DOI: 10.1080/00016489.2016.1276303] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONCLUSION Most of the cases with gene mutations of intra-cochlear etiology showed relatively good CI outcomes. To progress toward more solid evidence-based CI intervention, a greater number of reports including CI outcomes for specific gene mutations are desired. BACKGROUND Cochlear implantation (CI) is the most important and effective treatment for patients with profound sensorineural hearing loss. However, the outcomes of CI vary among patients. One of the reasons of this heterogeneous outcome for cochlear implantation is thought to be the heterogeneous nature of hearing loss. Indeed, genetic factors, the most common etiology in severe-to-profound hearing loss, might be one of the key determinants of outcomes for CI and electric acoustic stimulation (EAS). Patients with genetic causes involving an 'intra-cochlear' etiology show good CI/EAS outcomes. REVIEW This review article aimed to summarize the reports on CI/EAS outcomes in patients with special genetic causes as well as to assist in future clinical decision-making. Most of the cases were suspected of an intra-cochlear etiology, such as those with GJB2, SLC26A4, and OTOF mutations, which showed relatively good CI outcomes. However, there have only been a limited number of reports on patients with other gene mutations.
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Affiliation(s)
- Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
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Jepsen L, Kruth KA, Rubenstein PA, Sept D. Two Deafness-Causing Actin Mutations (DFNA20/26) Have Allosteric Effects on the Actin Structure. Biophys J 2016; 111:323-332. [PMID: 27463135 PMCID: PMC4968419 DOI: 10.1016/j.bpj.2016.06.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/03/2016] [Accepted: 06/09/2016] [Indexed: 12/21/2022] Open
Abstract
Point mutations in γ-cytoplasmic actin have been shown to result in autosomal-dominant, nonsyndromic, early-onset deafness. Two mutations at the same site, K118M and K118N, provide a unique opportunity to compare the effects of two dissimilar amino acid substitutions that produce a similar phenotype in humans. K118 resides in a helix that runs from K113 to T126, and mutations that alter the position, dynamics, and/or biochemistry of this helix can result in a wide range of pathologies. Using a combination of computational and experimental studies, both employing yeast actin, we find that these mutations at K118 result in changes in the structure and dynamics of the DNase-I loop, alterations in the structure of the H73 loop as well as the side-chain orientations of W79 and W86, changes in nucleotide exchange rates, and significant shifts in the twist of the actin monomer. Interestingly, in the case of K118N, the twist of the monomer is nearly identical to that of the F-actin protomer, and in vitro polymerization assays show that this mutation results in faster polymerization. Taken together, these results indicate that mutations at this site give rise to a series of small changes that can be tolerated in vivo but result in misregulation of actin assembly and dynamics.
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Affiliation(s)
- Lauren Jepsen
- Bioinformatics Graduate Program, University of Michigan, Ann Arbor, Michigan; Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan; Center for Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan
| | - Karina A Kruth
- Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Peter A Rubenstein
- Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - David Sept
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan; Center for Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan.
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29
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Di Donato N, Kuechler A, Vergano S, Heinritz W, Bodurtha J, Merchant SR, Breningstall G, Ladda R, Sell S, Altmüller J, Bögershausen N, Timms AE, Hackmann K, Schrock E, Collins S, Olds C, Rump A, Dobyns WB. Update on the ACTG1-associated Baraitser-Winter cerebrofrontofacial syndrome. Am J Med Genet A 2016; 170:2644-51. [PMID: 27240540 DOI: 10.1002/ajmg.a.37771] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 05/17/2016] [Indexed: 11/08/2022]
Abstract
Baraitser-Winter cerebrofrontofacial syndrome is caused by heterozygous missense mutations in one of the two ubiquitous cytoplasmic actin-encoding genes ACTB and ACTG1. Recently, we characterized the large cohort of 41 patients presenting with this condition. Our series contained 34 patients with mutations in ACTB and only nine with ACTG1 mutations. Here, we report on seven unrelated patients with six mutations in ACTG1-four novel and two previously reported. Only one of seven patients was clinically diagnosed with this disorder and underwent ACTB/ACTG1 targeted sequencing, four patients were screened as a part of the large lissencephaly cohort and two were tested with exome sequencing. Retrospectively, facial features were compatible with the diagnosis but significantly milder than previously reported in four patients, and non-specific in one. The pattern of malformations of cortical development was highly similar in four of six patients with available MRI images and encompassed frontal predominant pachygyria merging with the posterior predominant band heterotopia. Two remaining patients showed mild involvement consistent with bilaterally simplified gyration over the frontal lobes. Taken together, we expand the clinical spectrum of the ACTG1-associated Baraitser-Winter cerebrofrontofacial syndrome demonstrating the mild end of the facial and brain manifestations. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Nataliya Di Donato
- Institute for Clinical Genetics, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany.
| | - Alma Kuechler
- Institut für Humangenetik, Universitätsklinikum Essen, Essen, Germany
| | - Samantha Vergano
- Division of Medical Genetics and Metabolism, Children's Hospital of The King's Daughters, Norfolk, Virginia
| | | | - Joann Bodurtha
- Medical College of Virginia, Department of Human and Molecular Genetics, Richmond, Virginia
| | - Sabiha R Merchant
- Department of Pediatric Neurology, New York Presbyterian Hospital and Weill Cornell Medical College, New York, New York
| | - Galen Breningstall
- Department of Pediatric Neurology, Gillette Children's Specialty Healthcare, St. Paul, Minnesota
| | - Roger Ladda
- Penn State Hershey Children's Hospital, Hershey, Pennsylvania
| | - Susan Sell
- Penn State Hershey Children's Hospital, Hershey, Pennsylvania
| | | | - Nina Bögershausen
- Institute of Human Genetics, University Medical Center Göttingen, Göttingen, Germany
| | - Andrew E Timms
- Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, Seattle, Washington
| | - Karl Hackmann
- Institute for Clinical Genetics, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Evelin Schrock
- Institute for Clinical Genetics, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Sarah Collins
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Carissa Olds
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Andreas Rump
- Institute for Clinical Genetics, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - William B Dobyns
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington.,Department of Pediatrics, University of Washington, Seattle, Washington.,Department of Neurology, University of Washington, Seattle, Washington
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Kemerley A, Sloan C, Pfeifer W, Smith R, Drack A. A novel mutation in ACTG1 causing Baraitser-Winter syndrome with extremely variable expressivity in three generations. Ophthalmic Genet 2016; 38:152-156. [PMID: 27096712 DOI: 10.3109/13816810.2016.1164196] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Baraitser-Winter syndrome (cerebrofrontofacial syndrome, type 3) is a rare developmental disorder typified by hypertelorism, ptosis, high-arched eyebrows, ocular coloboma, and brain malformations. Other common manifestations include hearing loss, short stature, seizures, intellectual impairment, muscle dysfunction, and abnormalities of the kidney and urinary system. This syndrome is caused by missense mutations in the genes ACTB or ACTG1, both of which encode for cytoplasmic actin proteins crucial for proper development of many organs in the human body. There are no reports of familial transmission; all reported cases have been new mutations. However, different mutations in ACTG1 have been reported to cause isolated non-syndromic hearing loss, with many reported cases of autosomal dominant (AD) inheritance. We have identified a three-generation pedigree segregating a novel mutation in the ACTG1 gene that causes Baraitser-Winter Syndrome with extremely variable expressivity, leading to an initial diagnosis of isolated AD hearing loss in two members. Subtle optic nerve signs not previously reported in this syndrome are also documented in one patient.
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Affiliation(s)
- Andrew Kemerley
- a Department of Ophthalmology and Visual Sciences , University of Iowa , Iowa City , Iowa , USA
| | - Christina Sloan
- b Department of Otolaryngology , University of Iowa , Iowa City , Iowa , USA
| | - Wanda Pfeifer
- a Department of Ophthalmology and Visual Sciences , University of Iowa , Iowa City , Iowa , USA
| | - Richard Smith
- b Department of Otolaryngology , University of Iowa , Iowa City , Iowa , USA
| | - Arlene Drack
- a Department of Ophthalmology and Visual Sciences , University of Iowa , Iowa City , Iowa , USA
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Miyasaka Y, Shitara H, Suzuki S, Yoshimoto S, Seki Y, Ohshiba Y, Okumura K, Taya C, Tokano H, Kitamura K, Takada T, Hibino H, Shiroishi T, Kominami R, Yonekawa H, Kikkawa Y. Heterozygous mutation of Ush1g/Sans in mice causes early-onset progressive hearing loss, which is recovered by reconstituting the strain-specific mutation in Cdh23. Hum Mol Genet 2016; 25:2045-2059. [PMID: 26936824 DOI: 10.1093/hmg/ddw078] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 02/29/2016] [Indexed: 12/21/2022] Open
Abstract
Most clinical reports have suggested that patients with congenital profound hearing loss have recessive mutations in deafness genes, whereas dominant alleles are associated with progressive hearing loss (PHL). Jackson shaker (Ush1gjs) is a mouse model of recessive deafness that exhibits congenital profound deafness caused by the homozygous mutation of Ush1g/Sans on chromosome 11. We found that C57BL/6J-Ush1gjs/+ heterozygous mice exhibited early-onset PHL (ePHL) accompanied by progressive degeneration of stereocilia in the cochlear outer hair cells. Interestingly, ePHL did not develop in mutant mice with the C3H/HeN background, thus suggesting that other genetic factors are required for ePHL development. Therefore, we performed classical genetic analyses and found that the occurrence of ePHL in Ush1gjs/+ mice was associated with an interval in chromosome 10 that contains the cadherin 23 gene (Cdh23), which is also responsible for human deafness. To confirm this mutation effect, we generated C57BL/6J-Ush1gjs/+, Cdh23c.753A/G double-heterozygous mice by using the CRISPR/Cas9-mediated Cdh23c.753A>G knock-in method. The Cdh23c.753A/G mice harbored a one-base substitution (A for G), and the homozygous A allele caused moderate hearing loss with aging. Analyses revealed the complete recovery of ePHL and stereocilia degeneration in C57BL/6J-Ush1gjs/+ mice. These results clearly show that the development of ePHL requires at least two mutant alleles of the Ush1g and Cdh23 genes. Our results also suggest that because the SANS and CDH23 proteins form a complex in the stereocilia, the interaction between these proteins may play key roles in the maintenance of stereocilia and the prevention of ePHL.
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Affiliation(s)
- Yuki Miyasaka
- Mammalian Genetics Project, Graduate School of Medical and Dental Sciences
| | - Hiroshi Shitara
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
| | | | - Sachi Yoshimoto
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
| | | | - Yasuhiro Ohshiba
- Mammalian Genetics Project, Graduate School of Medical and Dental Sciences
| | - Kazuhiro Okumura
- Division of Oncogenomics, Cancer Genome Center, Chiba Cancer Center Research Institute, Chiba 260-0801, Japan
| | - Choji Taya
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Hisashi Tokano
- Department of Otolaryngology, Tokyo Medical and Dental University, Tokyo 113-0034, Japan and
| | - Ken Kitamura
- Department of Otolaryngology, Tokyo Medical and Dental University, Tokyo 113-0034, Japan and
| | - Toyoyuki Takada
- Mammalian Genetics Laboratory, National Institute of Genetics, Mishima 411-8540, Japan
| | - Hiroshi Hibino
- Department of Molecular Physiology, Niigata University School of Medicine, Niigata 951-8510, Japan
| | - Toshihiko Shiroishi
- Mammalian Genetics Laboratory, National Institute of Genetics, Mishima 411-8540, Japan
| | | | - Hiromichi Yonekawa
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Yoshiaki Kikkawa
- Mammalian Genetics Project, Graduate School of Medical and Dental Sciences,
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Yuan Y, Gao X, Huang B, Lu J, Wang G, Lin X, Qu Y, Dai P. Phenotypic Heterogeneity in a DFNA20/26 family segregating a novel ACTG1 mutation. BMC Genet 2016; 17:33. [PMID: 26832775 PMCID: PMC4736096 DOI: 10.1186/s12863-016-0333-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 01/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Genetic factors play an important role in hearing loss, contributing to approximately 60% of cases of congenital hearing loss. Autosomal dominant deafness accounts for approximately 20% of cases of hereditary hearing loss. Diseases with autosomal dominant inheritance often show pleiotropy, different degrees of penetrance, and variable expressivity. METHODS A three-generation Chinese family with autosomal dominant nonsyndromic hearing impairment (ADNSHI) was enrolled in this study. Audiometric data and blood samples were collected from the family. In total, 129 known human deafness genes were sequenced using next-generation sequencing (NGS) to identify the responsible gene mutation in the family. Whole Exome Sequencing (WES) was performed to exclude any other variant that cosegregated with the phenotype. RESULTS The age of onset of the affected family members was the second decade of life. The condition began with high-frequency hearing impairment in all family members excluding III:2. The novel ACTG1 c.638A > G (p.K213R) mutation was found in all affected family members and was not found in the unaffected family members. A heterozygous c.638A > G mutation in ACTG1 and homozygous c.109G > A (p.V37I) mutation in GJB2 were found in III:2, who was born with hearing loss. The WES result concurred with that of targeted sequencing of known deafness genes. CONCLUSIONS The novel mutation p.K213R in ACTG1 was found to be co-segregated with hearing loss and the genetic cause of ADNSHI in this family. A homozygous mutation associated with recessive inheritance only rarely co-acts with a dominant mutation to result in hearing loss in a dominant family. In such cases, the mutations in the two genes, as in ACTG1 and GJB2 in the present study, may result in a more severe phenotype. Targeted sequencing of known deafness genes is one of the best choices to identify the genetic cause in hereditary hearing loss families.
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Affiliation(s)
- Yongyi Yuan
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China. .,Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, 572000, People's Republic of China.
| | - Xue Gao
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
| | - Bangqing Huang
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, 572000, People's Republic of China.
| | - Jingqiao Lu
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, 30322-3030, USA.
| | - Guojian Wang
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
| | - Xi Lin
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, 30322-3030, USA.
| | - Yan Qu
- Third hospital of Hebei Medical University, Shijiazhuang, Hebei Province, 050051, People's Republic of China.
| | - Pu Dai
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
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Helios(®) Gene Gun-Mediated Transfection of the Inner Ear Sensory Epithelium: Recent Updates. Methods Mol Biol 2016; 1427:3-26. [PMID: 27259918 DOI: 10.1007/978-1-4939-3615-1_1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The transfection of vertebrate inner ear hair cells has proven to be challenging. Therefore, many laboratories attempt to use and improve different transfection methods. Each method has its own advantages and disadvantages. A particular researcher's skills in addition to available equipment and the type of experiment (in vivo or in vitro) likely determine the transfection method of choice. Biolistic delivery of exogenous DNA, mRNA, or siRNA, also known as Helios(®) Gene Gun-mediated transfection, uses the mechanical energy of compressed helium gas to bombard tissue with micron- or submicron-sized DNA or RNA-coated gold particles, which can penetrate and transfect cells in vitro or in vivo. Helios(®) Gene Gun-mediated transfection has several advantages: (1) it is simple enough to learn in a short time; (2) it is designed to overcome cell barriers even as tough as plant cell membrane or stratum corneum in the epidermis; (3) it can transfect cells deep inside a tissue such as specific neurons within a brain slice; (4) it can accommodate mRNA, siRNA, or DNA practically of any size to be delivered; and (5) it works well with various cell types including non-dividing, terminally differentiated cells that are difficult to transfect, such as neurons or mammalian inner ear sensory hair cells. The latter advantage is particularly important for inner ear research. The disadvantages of this method are: (1) low efficiency of transfection due to many variables that have to be adjusted and (2) potential mechanical damage of the tissue if the biolistic shot parameters are not optimal. This chapter provides a step-by-step protocol and critical evaluation of the Bio-Rad Helios(®) Gene Gun transfection method used to deliver green fluorescent protein (GFP)-tagged full-length cDNAs of myosin 15a, whirlin, β-actin, and Clic5 into rodent hair cells of the postnatal inner ear sensory epithelia in culture.
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Kawamoto H, Suzuki R, Ugaki M, Kawano S. Location of Gold Particles and Puncture of Tobacco Leaf Epidermis by Particle Bombardment. CYTOLOGIA 2016. [DOI: 10.1508/cytologia.81.455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Hiroki Kawamoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo
| | - Ryogo Suzuki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo
| | - Masashi Ugaki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo
| | - Shigeyuki Kawano
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo
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Abstract
Actin is the central building block of the actin cytoskeleton, a highly regulated filamentous network enabling dynamic processes of cells and simultaneously providing structure. Mammals have six actin isoforms that are very conserved and thus share common functions. Tissue-specific expression in part underlies their differential roles, but actin isoforms also coexist in various cell types and tissues, suggesting specific functions and preferential interaction partners. Gene deletion models, antibody-based staining patterns, gene silencing effects, and the occurrence of isoform-specific mutations in certain diseases have provided clues for specificity on the subcellular level and its consequences on the organism level. Yet, the differential actin isoform functions are still far from understood in detail. Biochemical studies on the different isoforms in pure form are just emerging, and investigations in cells have to deal with a complex and regulated system, including compensatory actin isoform expression.
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Affiliation(s)
- Christophe Ampe
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000, Ghent, Belgium.
| | - Marleen Van Troys
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000, Ghent, Belgium
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Zazo Seco C, Serrão de Castro L, van Nierop J, Morín M, Jhangiani S, Verver E, Schraders M, Maiwald N, Wesdorp M, Venselaar H, Spruijt L, Oostrik J, Schoots J, van Reeuwijk J, Lelieveld S, Huygen P, Insenser M, Admiraal R, Pennings R, Hoefsloot L, Arias-Vásquez A, de Ligt J, Yntema H, Jansen J, Muzny D, Huls G, van Rossum M, Lupski J, Moreno-Pelayo M, Kunst H, Kremer H, Kremer H. Allelic Mutations of KITLG, Encoding KIT Ligand, Cause Asymmetric and Unilateral Hearing Loss and Waardenburg Syndrome Type 2. Am J Hum Genet 2015; 97:647-60. [PMID: 26522471 DOI: 10.1016/j.ajhg.2015.09.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/24/2015] [Indexed: 01/04/2023] Open
Abstract
Linkage analysis combined with whole-exome sequencing in a large family with congenital and stable non-syndromic unilateral and asymmetric hearing loss (NS-UHL/AHL) revealed a heterozygous truncating mutation, c.286_303delinsT (p.Ser96Ter), in KITLG. This mutation co-segregated with NS-UHL/AHL as a dominant trait with reduced penetrance. By screening a panel of probands with NS-UHL/AHL, we found an additional mutation, c.200_202del (p.His67_Cys68delinsArg). In vitro studies revealed that the p.His67_Cys68delinsArg transmembrane isoform of KITLG is not detectable at the cell membrane, supporting pathogenicity. KITLG encodes a ligand for the KIT receptor. Also, KITLG-KIT signaling and MITF are suggested to mutually interact in melanocyte development. Because mutations in MITF are causative of Waardenburg syndrome type 2 (WS2), we screened KITLG in suspected WS2-affected probands. A heterozygous missense mutation, c.310C>G (p.Leu104Val), that segregated with WS2 was identified in a small family. In vitro studies revealed that the p.Leu104Val transmembrane isoform of KITLG is located at the cell membrane, as is wild-type KITLG. However, in culture media of transfected cells, the p.Leu104Val soluble isoform of KITLG was reduced, and no soluble p.His67_Cys68delinsArg and p.Ser96Ter KITLG could be detected. These data suggest that mutations in KITLG associated with NS-UHL/AHL have a loss-of-function effect. We speculate that the mechanism of the mutation underlying WS2 and leading to membrane incorporation and reduced secretion of KITLG occurs via a dominant-negative or gain-of-function effect. Our study unveils different phenotypes associated with KITLG, previously associated with pigmentation abnormalities, and will thereby improve the genetic counseling given to individuals with KITLG variants.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Hannie Kremer
- Hearing & Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen 6525GA, the Netherlands; The Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525GA, the Netherlands; Department of Human Genetics, Radboud University Medical Center, Nijmegen 6525GA, the Netherlands.
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Andrade LR. Evidence for changes in beta- and gamma-actin proportions during inner ear hair cell life. Cytoskeleton (Hoboken) 2015; 72:282-91. [PMID: 26033950 DOI: 10.1002/cm.21227] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 05/11/2015] [Accepted: 05/21/2015] [Indexed: 12/18/2022]
Abstract
Cytoplasmic actin isoforms beta (β-) and gamma (γ-) perform crucial physiological roles in inner ear hair cells (HC). The stereocilium, which is structured by parallel actin filaments composed of both isoforms, is the responsive organelle to mechanical stimuli such as sound, gravity and head movements. Modifications in isoform proportions affect the function of the stereocilia as previously shown in genetic studies of mutant mice. Here, immunogold labeling TEM studies in mice showed that both β- and γ-actin isoforms colocalize throughout stereocilia actin filaments, adherens junctions and cuticular plates as early as embryonic stage 16.5. Gold-particle quantification indicated that there was 40% more γ- actin than β-actin at E16.5. In contrast, β- and γ-actin were equally concentrated in adult stereocilia of cochlear and vestibular HC. Interestingly, all actin-based structures presented almost five-fold more β-actin than γ-actin in 22 month- old mice, suggesting that γ-actin is probably under-expressed during the aging process. These data provide evidence of dynamic modifications of the actin isoforms in stereocilia, cuticular plates and cell junctions during the whole HC life.
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Affiliation(s)
- Leonardo R Andrade
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA.,Laboratory of Biomineralization, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
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Miyagawa M, Nishio SY, Ichinose A, Iwasaki S, Murata T, Kitajiri SI, Usami SI. Mutational Spectrum and Clinical Features of Patients With ACTG1 Mutations Identified by Massively Parallel DNA Sequencing. Ann Otol Rhinol Laryngol 2015; 124 Suppl 1:84S-93S. [DOI: 10.1177/0003489415575057] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objectives: ACTG1 has been reported to be a causative gene for autosomal dominant sensorineural hearing loss, DFNA20/26. In this study we sought to clarify the detailed mutational spectrum, clinical features, and genotype-phenotype correlations. Methods: Massively parallel DNA sequencing (MPS) of 63 target candidate genes was used to screen 1120 Japanese hearing loss patients. Results: MPS screening successfully identified 4 ACTG1 mutations in 5 families. The majority of patients showed high frequency–involved progressive hearing loss, with the age of onset mostly in the first or second decade. One patient received electric acoustic stimulation (EAS), which showed a good outcome. Conclusions: Target exon-sequencing using MPS was proven to be a powerful new clinical diagnostic tool for the identification of rare causative genes such as ACTG1. The present clinical findings not only confirmed those previous reports but also provided important new clinical information.
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Affiliation(s)
- Maiko Miyagawa
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Aya Ichinose
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Satoshi Iwasaki
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Otorhinolaryngology, International University of Health and Welfare, Mita Hospital, Tokyo, Japan
| | - Takaaki Murata
- Department of Otorhinolaryngology, Gunma University School of Medicine, Maebashi, Japan
| | - Shin-ichiro Kitajiri
- Department of Otorhinolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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Kandasamy MK, McKinney EC, Roy E, Meagher RB. Ascomycete fungal actins differentially support plant spatial cell and organ development. Cytoskeleton (Hoboken) 2015; 72:80-92. [PMID: 25428798 DOI: 10.1002/cm.21198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 11/18/2014] [Accepted: 11/23/2014] [Indexed: 01/18/2023]
Abstract
Actin interacts with a wide variety of cytoplasmic and nuclear proteins to support spatial development in nearly all eukaryotes. Null mutations in plant vegetative actins produce dramatically altered cell, tissue, and organ morphologies. Animal cytoplasmic actins (e.g., human HsACTB, HsACTG1) and some ancestral protist actins fully suppress these mutant phenotypes suggesting that some animal, plant, and protist actins share functional competence for spatial development. Considering that fungi have a phylogenetic origin closer to animals than plants, we were interested to explore whether the fungal actins may have this same capacity to function in plants and support development. We ectopically expressed actins from four highly divergent ascomycete fungi in two different Arabidopsis double vegetative actin null mutants. We found that expression of actin from the earliest diverging ascomycete subphyla, the archiascomycete Schizosaccharomyces pombe, qualitatively and quantitatively suppressed the root cell polarity and root organ developmental defects of act8/act7 mutants and the root-hairless cell elongation phenotype of act2/act8 mutants. Interestingly, the actin from the pyrenomycete Neurospora crassa was modestly effective in the suppression of vegetative actin mutant phenotypes. In contrast, actins from the saccharomycetes Saccharomyces cerevisiae and Candida albicans were unable to support any aspect of plant development, and moreover induced severe dwarfism and sterility. These data imply that basal fungi inherited an actin with full competence for spatial development from their protist ancestor and maintained it via non-progressive sequence evolution, while the later more derived fungal species lost these activities.
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Affiliation(s)
- Muthugapatti K Kandasamy
- Department of Genetics, Davison Life Sciences Complex, University of Georgia, Athens, Georgia; Biomedical Microscopy Core, Coverdell Center, University of Georgia, Athens, Georgia
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Nishio SY, Hayashi Y, Watanabe M, Usami SI. Clinical application of a custom AmpliSeq library and ion torrent PGM sequencing to comprehensive mutation screening for deafness genes. Genet Test Mol Biomarkers 2015; 19:209-17. [PMID: 25587757 DOI: 10.1089/gtmb.2014.0252] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Congenital hearing loss is one of the most common sensory disorders, with 50-70% of cases attributable to genetic causes. Although recent advances in the identification of deafness genes have resulted in more accurate molecular diagnosis, leading to the better determination of suitable clinical interventions, difficulties remain with regard to clinical applications due to the extreme genetic heterogeneity of deafness. AIM Toward more effective genetic testing, we adopted Massively Parallel DNA Sequencing (MPS) of target genes using an Ion PGM™ system and an Ion AmpliSeq™ panel to diagnose common mutations responsible for deafness and discover rare causative gene mutations. Before its clinical application, we investigated the accuracy of MPS-based genetic testing. RESULTS We compared the results of Invader assay-based genetic screening, the accuracy of which has already been verified in previous studies, with those of MPS-based genetic testing for a large population of Japanese deafness patients and revealed that over 99.98% of the results were the same for each genetic testing system. CONCLUSION The Ion Personal Genome Machine system had sufficient uniformity and accuracy for application to the clinical diagnosis of common causative mutations and efficiently identified rare causative mutations and/or mutation candidates.
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Affiliation(s)
- Shin-Ya Nishio
- 1 Department of Otorhinolaryngology, Shinshu University School of Medicine , Matsumoto, Japan
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41
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Baraitser-Winter cerebrofrontofacial syndrome: delineation of the spectrum in 42 cases. Eur J Hum Genet 2014; 23:292-301. [PMID: 25052316 DOI: 10.1038/ejhg.2014.95] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 04/05/2014] [Accepted: 04/30/2014] [Indexed: 11/08/2022] Open
Abstract
Baraitser-Winter, Fryns-Aftimos and cerebrofrontofacial syndrome types 1 and 3 have recently been associated with heterozygous gain-of-function mutations in one of the two ubiquitous cytoplasmic actin-encoding genes ACTB and ACTG1 that encode β- and γ-actins. We present detailed phenotypic descriptions and neuroimaging on 36 patients analyzed by our group and six cases from the literature with a molecularly proven actinopathy (9 ACTG1 and 33 ACTB). The major clinical anomalies are striking dysmorphic facial features with hypertelorism, broad nose with large tip and prominent root, congenital non-myopathic ptosis, ridged metopic suture and arched eyebrows. Iris or retinal coloboma is present in many cases, as is sensorineural deafness. Cleft lip and palate, hallux duplex, congenital heart defects and renal tract anomalies are seen in some cases. Microcephaly may develop with time. Nearly all patients with ACTG1 mutations, and around 60% of those with ACTB mutations have some degree of pachygyria with anteroposterior severity gradient, rarely lissencephaly or neuronal heterotopia. Reduction of shoulder girdle muscle bulk and progressive joint stiffness is common. Early muscular involvement, occasionally with congenital arthrogryposis, may be present. Progressive, severe dystonia was seen in one family. Intellectual disability and epilepsy are variable in severity and largely correlate with CNS anomalies. One patient developed acute lymphocytic leukemia, and another a cutaneous lymphoma, indicating that actinopathies may be cancer-predisposing disorders. Considering the multifaceted role of actins in cell physiology, we hypothesize that some clinical manifestations may be partially mutation specific. Baraitser-Winter cerebrofrontofacial syndrome is our suggested designation for this clinical entity.
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42
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Genetics of auditory mechano-electrical transduction. Pflugers Arch 2014; 467:49-72. [PMID: 24957570 PMCID: PMC4281357 DOI: 10.1007/s00424-014-1552-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 06/04/2014] [Accepted: 06/05/2014] [Indexed: 12/29/2022]
Abstract
The hair bundles of cochlear hair cells play a central role in the auditory mechano-electrical transduction (MET) process. The identification of MET components and of associated molecular complexes by biochemical approaches is impeded by the very small number of hair cells within the cochlea. In contrast, human and mouse genetics have proven to be particularly powerful. The study of inherited forms of deafness led to the discovery of several essential proteins of the MET machinery, which are currently used as entry points to decipher the associated molecular networks. Notably, MET relies not only on the MET machinery but also on several elements ensuring the proper sound-induced oscillation of the hair bundle or the ionic environment necessary to drive the MET current. Here, we review the most significant advances in the molecular bases of the MET process that emerged from the genetics of hearing.
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Rubenstein PA, Wen KK. Insights into the effects of disease-causing mutations in human actins. Cytoskeleton (Hoboken) 2014; 71:211-29. [PMID: 24574087 DOI: 10.1002/cm.21169] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 02/13/2013] [Accepted: 02/19/2014] [Indexed: 01/04/2023]
Abstract
Mutations in all six actins in humans have now been shown to cause diseases. However, a number of factors have made it difficult to gain insight into how the changes in actin functions brought about by these pathogenic mutations result in the disease phenotype. These include the presence of multiple actins in the same cell, limited accessibility to pure mutant material, and complexities associated with the structures and their component cells that manifest the diseases. To try to circumvent these difficulties, investigators have turned to the use of model systems. This review describes these various approaches, the initial results obtained using them, and the insight they have provided into allosteric mechanisms that govern actin function. Although results so far have not explained a particular disease phenotype at the molecular level, they have provided valuable insight into actin function at the mechanistic level which can be utilized in the future to delineate the molecular bases of these different actinopathies.
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Affiliation(s)
- Peter A Rubenstein
- Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, Iowa
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Luo Y, Kong F, Wang Z, Chen D, Liu Q, Wang T, Xu R, Wang X, Yang JY. Loss of ASAP3 destabilizes cytoskeletal protein ACTG1 to suppress cancer cell migration. Mol Med Rep 2013; 9:387-94. [PMID: 24284654 DOI: 10.3892/mmr.2013.1831] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 10/31/2013] [Indexed: 11/06/2022] Open
Abstract
ArfGAP with SH3 domain, ankyrin repeat and PH domain 3 (ASAP3), previously known as ACAP4, DDEFL1 and UPLC1, is considered to be an important regulator in cancer cell migration/invasion and actin-based cytoskeletal remodeling. However, the underlying mechanisms through which ASAP3 mediates these processes are not well-elucidated. This study reported that in certain types of cancer cells, loss of ASAP3 suppressed cell migration/invasion, in part by destabilizing γ-actin-1 (ACTG1), a cytoskeletal protein considered to be an integral component of the cell migratory machinery, essential for the rearrangement of the dynamic cytoskeletal networks and important in diseases, such as brain malformation, hearing loss and cancer development. The data, for the first time, link ASAP3 with ACTG1 in the regulation of cytoskeletal maintenance and cell motility.
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Affiliation(s)
- Yu Luo
- School of Nursing, The Third Military Medical University, Chongqing 400038, P.R. China
| | - Fang Kong
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiang'an, Xiamen, Fujian 361102, P.R. China
| | - Zhen Wang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiang'an, Xiamen, Fujian 361102, P.R. China
| | - Dahan Chen
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiang'an, Xiamen, Fujian 361102, P.R. China
| | - Qiuyan Liu
- School of Biomedical Sciences, Huaqiao University, Quanzhou, Fujian 362021, P.R. China
| | - Tao Wang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiang'an, Xiamen, Fujian 361102, P.R. China
| | - Ruian Xu
- School of Biomedical Sciences, Huaqiao University, Quanzhou, Fujian 362021, P.R. China
| | - Xianyuan Wang
- School of Nursing, The Third Military Medical University, Chongqing 400038, P.R. China
| | - James Y Yang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiang'an, Xiamen, Fujian 361102, P.R. China
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Mutai H, Suzuki N, Shimizu A, Torii C, Namba K, Morimoto N, Kudoh J, Kaga K, Kosaki K, Matsunaga T. Diverse spectrum of rare deafness genes underlies early-childhood hearing loss in Japanese patients: a cross-sectional, multi-center next-generation sequencing study. Orphanet J Rare Dis 2013; 8:172. [PMID: 24164807 PMCID: PMC4231469 DOI: 10.1186/1750-1172-8-172] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 10/05/2013] [Indexed: 11/16/2022] Open
Abstract
Background Genetic tests for hereditary hearing loss inform clinical management of patients and can provide the first step in the development of therapeutics. However, comprehensive genetic tests for deafness genes by Sanger sequencing is extremely expensive and time-consuming. Next-generation sequencing (NGS) technology is advantageous for genetic diagnosis of heterogeneous diseases that involve numerous causative genes. Methods Genomic DNA samples from 58 subjects with hearing loss from 15 unrelated Japanese families were subjected to NGS to identify the genetic causes of hearing loss. Subjects did not have pathogenic GJB2 mutations (the gene most often associated with inherited hearing loss), mitochondrial m.1555A>G or 3243A>G mutations, enlarged vestibular aqueduct, or auditory neuropathy. Clinical features of subjects were obtained from medical records. Genomic DNA was subjected to a custom-designed SureSelect Target Enrichment System to capture coding exons and proximal flanking intronic sequences of 84 genes responsible for nonsyndromic or syndromic hearing loss, and DNA was sequenced by Illumina GAIIx (paired-end read). The sequences were mapped and quality-checked using the programs BWA, Novoalign, Picard, and GATK, and analyzed by Avadis NGS. Results Candidate genes were identified in 7 of the 15 families. These genes were ACTG1, DFNA5, POU4F3, SLC26A5, SIX1, MYO7A, CDH23, PCDH15, and USH2A, suggesting that a variety of genes underlie early-childhood hearing loss in Japanese patients. Mutations in Usher syndrome-related genes were detected in three families, including one double heterozygous mutation of CDH23 and PCDH15. Conclusion Targeted NGS analysis revealed a diverse spectrum of rare deafness genes in Japanese subjects and underscores implications for efficient genetic testing.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Tatsuo Matsunaga
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro, Tokyo 152-8902, Japan.
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Miyagawa M, Nishio SY, Ikeda T, Fukushima K, Usami SI. Massively parallel DNA sequencing successfully identifies new causative mutations in deafness genes in patients with cochlear implantation and EAS. PLoS One 2013; 8:e75793. [PMID: 24130743 PMCID: PMC3794008 DOI: 10.1371/journal.pone.0075793] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 08/21/2013] [Indexed: 02/02/2023] Open
Abstract
Genetic factors, the most common etiology in severe to profound hearing loss, are one of the key determinants of Cochlear Implantation (CI) and Electric Acoustic Stimulation (EAS) outcomes. Satisfactory auditory performance after receiving a CI/EAS in patients with certain deafness gene mutations indicates that genetic testing would be helpful in predicting CI/EAS outcomes and deciding treatment choices. However, because of the extreme genetic heterogeneity of deafness, clinical application of genetic information still entails difficulties. Target exon sequencing using massively parallel DNA sequencing is a new powerful strategy to discover rare causative genes in Mendelian disorders such as deafness. We used massive sequencing of the exons of 58 target candidate genes to analyze 8 (4 early-onset, 4 late-onset) Japanese CI/EAS patients, who did not have mutations in commonly found genes including GJB2, SLC26A4, or mitochondrial 1555A>G or 3243A>G mutations. We successfully identified four rare causative mutations in the MYO15A, TECTA, TMPRSS3, and ACTG1 genes in four patients who showed relatively good auditory performance with CI including EAS, suggesting that genetic testing may be able to predict the performance after implantation.
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Affiliation(s)
- Maiko Miyagawa
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Takuo Ikeda
- Department of Otolaryngology, Tsudumigaura Handicapped Children’s Hospital, Shunan, Japan
| | - Kunihiro Fukushima
- Department of Otorhinolaryngology, Okayama University School of Medicine, Okayama, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- * E-mail:
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Johnston JJ, Wen KK, Keppler-Noreuil K, McKane M, Maiers JL, Greiner A, Sapp JC, DeMali KA, Rubenstein PA, Biesecker LG. Functional analysis of a de novo ACTB mutation in a patient with atypical Baraitser-Winter syndrome. Hum Mutat 2013; 34:1242-9. [PMID: 23649928 PMCID: PMC3745514 DOI: 10.1002/humu.22350] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 04/30/2013] [Indexed: 11/08/2022]
Abstract
Exome sequence analysis can be instrumental in identifying the genetic etiology behind atypical disease. We report a patient presenting with microcephaly, dysmorphic features, and intellectual disability with a tentative diagnosis of Dubowitz syndrome. Exome analysis was performed on the patient and both parents. A de novo missense variant was identified in ACTB, c.349G>A, p.E117K. Recent work in Baraitser-Winter syndrome has identified ACTB and ACTG1 mutations in a cohort of individuals, and we rediagnosed the patient with atypical Baraitser-Winter syndrome. We performed functional characterization of the variant actin and show that it alters cell adhesion and polymer formation supporting its role in disease. We present the clinical findings in the patient, comparison of this patient to other patients with ACTB/ACTG1 mutations, and results from actin functional studies that demonstrate novel functional attributes of this mutant protein.
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Affiliation(s)
- Jennifer J. Johnston
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | | | - Kim Keppler-Noreuil
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | | | | | | | - Julie C. Sapp
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | | | | | | | - Leslie G. Biesecker
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
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48
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Müller M, Diensthuber RP, Chizhov I, Claus P, Heissler SM, Preller M, Taft MH, Manstein DJ. Distinct functional interactions between actin isoforms and nonsarcomeric myosins. PLoS One 2013; 8:e70636. [PMID: 23923011 PMCID: PMC3724804 DOI: 10.1371/journal.pone.0070636] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 06/26/2013] [Indexed: 02/07/2023] Open
Abstract
Despite their near sequence identity, actin isoforms cannot completely replace each other in vivo and show marked differences in their tissue-specific and subcellular localization. Little is known about isoform-specific differences in their interactions with myosin motors and other actin-binding proteins. Mammalian cytoplasmic β- and γ-actin interact with nonsarcomeric conventional myosins such as the members of the nonmuscle myosin-2 family and myosin-7A. These interactions support a wide range of cellular processes including cytokinesis, maintenance of cell polarity, cell adhesion, migration, and mechano-electrical transduction. To elucidate differences in the ability of isoactins to bind and stimulate the enzymatic activity of individual myosin isoforms, we characterized the interactions of human skeletal muscle α-actin, cytoplasmic β-actin, and cytoplasmic γ-actin with human myosin-7A and nonmuscle myosins-2A, -2B and -2C1. In the case of nonmuscle myosins-2A and -2B, the interaction with either cytoplasmic actin isoform results in 4-fold greater stimulation of myosin ATPase activity than was observed in the presence of α-skeletal muscle actin. Nonmuscle myosin-2C1 is most potently activated by β-actin and myosin-7A by γ-actin. Our results indicate that β- and γ-actin isoforms contribute to the modulation of nonmuscle myosin-2 and myosin-7A activity and thereby to the spatial and temporal regulation of cytoskeletal dynamics. FRET-based analyses show efficient copolymerization abilities for the actin isoforms in vitro. Experiments with hybrid actin filaments show that the extent of actomyosin coupling efficiency can be regulated by the isoform composition of actin filaments.
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Affiliation(s)
- Mirco Müller
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | | | - Igor Chizhov
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Peter Claus
- Institute of Neuroanatomy, Hannover Medical School, Hannover, Germany
| | - Sarah M. Heissler
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Matthias Preller
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Manuel H. Taft
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Dietmar J. Manstein
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
- * E-mail:
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Blache U, Silván U, Plodinec M, Suetterlin R, Jakob R, Klebba I, Bentires-Alj M, Aebi U, Schoenenberger CA. A tumorigenic actin mutant alters fibroblast morphology and multicellular assembly properties. Cytoskeleton (Hoboken) 2013; 70:635-50. [DOI: 10.1002/cm.21120] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 06/07/2013] [Accepted: 06/17/2013] [Indexed: 01/19/2023]
Affiliation(s)
- Ulrich Blache
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
| | - Unai Silván
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
| | - Marija Plodinec
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
| | - Rosmarie Suetterlin
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
| | - Roman Jakob
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
| | - Ina Klebba
- Mechanisms of Cancer; Friedrich Miescher Institute for Biomedical Research; Basel Switzerland
| | - Mohamed Bentires-Alj
- Mechanisms of Cancer; Friedrich Miescher Institute for Biomedical Research; Basel Switzerland
| | - Ueli Aebi
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
| | - Cora-Ann Schoenenberger
- Focal Area Structural Biology and Biophysics; Biozentrum; University of Basel; Basel Switzerland
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Wen KK, McKane M, Rubenstein PA. Importance of a Lys113-Glu195 intermonomer ionic bond in F-actin stabilization and regulation by yeast formins Bni1p and Bnr1p. J Biol Chem 2013; 288:19140-53. [PMID: 23653364 DOI: 10.1074/jbc.m113.474122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proper actin cytoskeletal function requires actin's ability to generate a stable filament and requires that this reaction be regulated by actin-binding proteins via allosteric effects on the actin. A proposed ionic interaction in the actin filament interior between Lys(113) of one monomer and Glu(195) of a monomer in the apposing strand potentially fosters cross-strand stabilization and allosteric communication between the filament interior and exterior. We interrupted the potential interaction by creating either K113E or E195K actin. By combining the two, we also reversed the interaction with a K113E/E195K (E/K) mutant. In all cases, we isolated viable cells expressing only the mutant actin. Either single mutant cell displays significantly decreased growth in YPD medium. This deficit is rescued in the double mutant. All three mutants display abnormal phalloidin cytoskeletal staining. K113E actin exhibits a critical concentration of polymerization 4 times higher than WT actin, nucleates more poorly, and forms shorter filaments. Restoration of the ionic bond, E/K, eliminates most of these problems. E195K actin behaves much more like WT actin, indicating accommodation of the neighboring lysines. Both Bni1 and Bnr1 formin FH1-FH2 fragment accelerate polymerization of WT, E/K, and to a lesser extent E195K actin. Bni1p FH1-FH2 dramatically inhibits K113E actin polymerization, consistent with barbed end capping. However, Bnr1p FH1-FH2 restores K113E actin polymerization, forming single filaments. In summary, the proposed ionic interaction plays an important role in filament stabilization and in the propagation of allosteric changes affecting formin regulation in an isoform-specific fashion.
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Affiliation(s)
- Kuo-Kuang Wen
- Department of Biochemistry, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242, USA
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