1
|
Horsthemke M, Arnaud CA, Hanley PJ. Are the class 18 myosins Myo18A and Myo18B specialist sarcomeric proteins? Front Physiol 2024; 15:1401717. [PMID: 38784114 PMCID: PMC11112018 DOI: 10.3389/fphys.2024.1401717] [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: 03/15/2024] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Initially, the two members of class 18 myosins, Myo18A and Myo18B, appeared to exhibit highly divergent functions, complicating the assignment of class-specific functions. However, the identification of a striated muscle-specific isoform of Myo18A, Myo18Aγ, suggests that class 18 myosins may have evolved to complement the functions of conventional class 2 myosins in sarcomeres. Indeed, both genes, Myo18a and Myo18b, are predominantly expressed in the heart and somites, precursors of skeletal muscle, of developing mouse embryos. Genetic deletion of either gene in mice is embryonic lethal and is associated with the disorganization of cardiac sarcomeres. Moreover, Myo18Aγ and Myo18B localize to sarcomeric A-bands, albeit the motor (head) domains of these unconventional myosins have been both deduced and biochemically demonstrated to exhibit negligible ATPase activity, a hallmark of motor proteins. Instead, Myo18Aγ and Myo18B presumably coassemble with thick filaments and provide structural integrity and/or internal resistance through interactions with F-actin and/or other proteins. In addition, Myo18Aγ and Myo18B may play distinct roles in the assembly of myofibrils, which may arise from actin stress fibers containing the α-isoform of Myo18A, Myo18Aα. The β-isoform of Myo18A, Myo18Aβ, is similar to Myo18Aα, except that it lacks the N-terminal extension, and may serve as a negative regulator through heterodimerization with either Myo18Aα or Myo18Aγ. In this review, we contend that Myo18Aγ and Myo18B are essential for myofibril structure and function in striated muscle cells, while α- and β-isoforms of Myo18A play diverse roles in nonmuscle cells.
Collapse
Affiliation(s)
- Markus Horsthemke
- IMM Institute for Molecular Medicine, HMU Health and Medical University Potsdam, Potsdam, Germany
| | - Charles-Adrien Arnaud
- IMM Institute for Molecular Medicine, HMU Health and Medical University Potsdam, Potsdam, Germany
- Department of Medicine, Science Faculty, MSB Medical School Berlin, Berlin, Germany
| | - Peter J. Hanley
- IMM Institute for Molecular Medicine, HMU Health and Medical University Potsdam, Potsdam, Germany
| |
Collapse
|
2
|
Cortada M, Levano S, Hall MN, Bodmer D. mTORC2 regulates auditory hair cell structure and function. iScience 2023; 26:107687. [PMID: 37694145 PMCID: PMC10484995 DOI: 10.1016/j.isci.2023.107687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/14/2023] [Accepted: 08/17/2023] [Indexed: 09/12/2023] Open
Abstract
mTOR broadly controls cell growth, but little is known about the role of mTOR complex 2 (mTORC2) in the inner ear. To investigate the role of mTORC2 in sensory hair cells (HCs), we generated HC-specific Rictor knockout (HC-RicKO) mice. HC-RicKO mice exhibited early-onset, progressive, and profound hearing loss. Increased DPOAE thresholds indicated outer HC dysfunction. HCs are lost, but this occurs after hearing loss. Ultrastructural analysis revealed stunted and absent stereocilia in outer HCs. In inner HCs, the number of synapses was significantly decreased and the remaining synapses displayed a disrupted actin cytoskeleton and disorganized Ca2+ channels. Thus, the mTORC2 signaling pathway plays an important role in regulating auditory HC structure and function via regulation of the actin cytoskeleton. These results provide molecular insights on a central regulator of cochlear HCs and thus hearing.
Collapse
Affiliation(s)
- Maurizio Cortada
- Department of Biomedicine, University of Basel, CH-4031 Basel, Switzerland
| | - Soledad Levano
- Department of Biomedicine, University of Basel, CH-4031 Basel, Switzerland
| | | | - Daniel Bodmer
- Department of Biomedicine, University of Basel, CH-4031 Basel, Switzerland
- Clinic for Otorhinolaryngology, Head and Neck Surgery, University of Basel Hospital, CH-4031 Basel, Switzerland
| |
Collapse
|
3
|
Vartanian V, Krey JF, Chatterjee P, Curtis A, Six M, Rice SPM, Jones SM, Sampath H, Allen CN, Ryals RC, Lloyd RS, Barr‐Gillespie PG. Spontaneous allelic variant in deafness-blindness gene Ush1g resulting in an expanded phenotype. GENES, BRAIN, AND BEHAVIOR 2023; 22:e12849. [PMID: 37328946 PMCID: PMC10393423 DOI: 10.1111/gbb.12849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/05/2023] [Accepted: 05/07/2023] [Indexed: 06/18/2023]
Abstract
Relationships between novel phenotypic behaviors and specific genetic alterations are often discovered using target-specific, directed mutagenesis or phenotypic selection following chemical mutagenesis. An alternative approach is to exploit deficiencies in DNA repair pathways that maintain genetic integrity in response to spontaneously induced damage. Mice deficient in the DNA glycosylase NEIL1 show elevated spontaneous mutations, which arise from translesion DNA synthesis past oxidatively induced base damage. Several litters of Neil1 knockout mice included animals that were distinguished by their backwards-walking behavior in open-field environments, while maintaining frantic forward movements in their home cage environment. Other phenotypic manifestations included swim test failures, head tilting and circling. Mapping of the mutation that conferred these behaviors showed the introduction of a stop codon at amino acid 4 of the Ush1g gene. Ush1gbw/bw null mice displayed auditory and vestibular defects that are commonly seen with mutations affecting inner-ear hair-cell function, including a complete lack of auditory brainstem responses and vestibular-evoked potentials. As in other Usher syndrome type I mutant mouse lines, hair cell phenotypes included disorganized and split hair bundles, as well as altered distribution of proteins for stereocilia that localize to the tips of row 1 or row 2. Disruption to the bundle and kinocilium displacement suggested that USH1G is essential for forming the hair cell's kinocilial links. Consistent with other Usher type 1 models, Ush1gbw/bw mice had no substantial retinal degeneration compared with Ush1gbw /+ controls. In contrast to previously described Ush1g alleles, this new allele provides the first knockout model for this gene.
Collapse
Affiliation(s)
- Vladimir Vartanian
- Oregon Institute of Occupational Health SciencesOregon Health & Science UniversityPortlandOregonUSA
| | - Jocelyn F. Krey
- Oregon Hearing Research Center and Vollum InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Paroma Chatterjee
- Oregon Hearing Research Center and Vollum InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Allison Curtis
- Department of Ophthalmology, Casey Eye InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Makayla Six
- Department of Ophthalmology, Casey Eye InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Sean P. M. Rice
- Oregon Institute of Occupational Health Sciences and School of Public HealthOregon Health & Science University‐Portland State UniversityPortlandOregonUSA
| | - Sherri M. Jones
- Department of Special Education and Communication DisordersUniversity of Nebraska‐LincolnLincolnNebraskaUSA
| | - Harini Sampath
- Department of Nutritional Sciences and New Jersey Institute for Food, Nutrition, and HealthRutgers UniversityNew BrunswickNew JerseyUSA
| | - Charles N. Allen
- Oregon Institute of Occupational Health Sciences and Department of Behavioral NeuroscienceOregon Health & Science UniversityPortlandOregonUSA
| | - Renee C. Ryals
- Department of Ophthalmology, Casey Eye InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - R. Stephen Lloyd
- Oregon Institute of Occupational Health SciencesOregon Health & Science UniversityPortlandOregonUSA
- Department of Molecular and Medical GeneticsOregon Health & Science UniversityPortlandOregonUSA
| | - Peter G. Barr‐Gillespie
- Oregon Hearing Research Center and Vollum InstituteOregon Health & Science UniversityPortlandOregonUSA
| |
Collapse
|
4
|
Petrova N, Tebieva I, Kadyshev V, Getoeva Z, Balinova N, Marakhonov A, Vasilyeva T, Ginter E, Kutsev S, Zinchenko R. Hereditary etiology of non-syndromic sensorineural hearing loss in the Republic of North Ossetia-Alania. PeerJ 2023; 11:e14514. [PMID: 36743950 PMCID: PMC9893906 DOI: 10.7717/peerj.14514] [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: 07/13/2022] [Accepted: 11/14/2022] [Indexed: 01/31/2023] Open
Abstract
More than 50% of congenital hearing loss is hereditary, in which the majority form is non-syndromic. In this study we estimate the most prevalent pathogenic genetic changes in an Ossetian cohort of patients. This is useful for local public health officials to promote genetic counseling of affected families with regard to high allele frequencies of prevalent pathogenic variants and assortative mating in the community of people with hearing loss. In this study, genetic heterogeneity of hereditary non-syndromic sensorineural hearing loss (NSNHL) in a cohort of 109 patients and an assessment of the frequency of two GJB2 gene pathogenic variants in a cohort of 349 healthy individuals from the populations of the Republic of North Ossetia-Alania (RNO-Alania) were assessed. The molecular genetic cause of NSNHL in the GJB2 gene in RNO-Alania was confirmed in ~30% of the cases, including ~27% in Ossetians. In Russian patients, the most frequent variant is GJB2:c.35delG (~83%). The GJB2:c.358_360delGAG variant was found to be the most frequent among Ossetians (~54%). Two genetic variants in GJB2, c.35delG and c.358_360delGAG, accounted for 91% of GJB2 pathogenic alleles in the Ossetian patients. A search for large genome rearrangements revealed etiological cause in two Ossetian patients, a deletion at the POU3F4 gene locus associated with X-linked hearing loss (type DFNX2). In another Ossetian patient, a biallelic pathogenic variant in the MYO15A gene caused hearing loss type DFNB3 was identified, and in one Russian family a heterozygous MYH14 gene variant associated with dominant NSNHL was found. Thus, the informative value of the diagnosis was ~37% among all patients with NSNHL from RNO-Alania and ~32% among the Ossetians. These estimates correspond to the literature data on the fraction of recessive genetic forms of hearing loss within the affected population. The importance of this study consists not only in the estimation of the most prevalent pathogenic genetic changes in the Ossetian cohort of patients which could be useful for the public health but also in the genetic counselling of the affected families with regard to the high allele frequencies of revealed pathogenic variants as well as to the assortative mating in community of people with hearing loss.
Collapse
Affiliation(s)
- Nika Petrova
- Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Inna Tebieva
- North Ossetian State Medical Academy of the Ministry of Health of the Russian Federation, Beslan, Russian Federation,Medical and Genetic Consultation of the Republican Children’s Clinical Hospital of the Republic of North Ossetia–Alania, Vladikavkaz, Russian Federation
| | - Vitaly Kadyshev
- Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Zalina Getoeva
- Pravoberezhnaya Central Clinical Hospital of the Ministry of Health of the Republic of North Ossetia–Alania, Vladikavkaz, Russian Federation
| | - Natalia Balinova
- Research Centre for Medical Genetics, Moscow, Russian Federation
| | | | | | - Evgeny Ginter
- Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Sergey Kutsev
- Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Rena Zinchenko
- Research Centre for Medical Genetics, Moscow, Russian Federation,N. A. Semashko National Research Institute of Public Health, Moscow, Russian Federation
| |
Collapse
|
5
|
Moreland ZG, Bird JE. Myosin motors in sensory hair bundle assembly. Curr Opin Cell Biol 2022; 79:102132. [PMID: 36257241 DOI: 10.1016/j.ceb.2022.102132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/02/2022] [Accepted: 09/07/2022] [Indexed: 01/31/2023]
Abstract
Mechanosensory hair bundles are assembled from actin-based stereocilia that project from the apical surface of hair cells in the inner ear. Stereocilia architecture is critical for the transduction of sound and accelerations, and structural defects in these mechano-sensors are a clinical cause of hearing and balance disorders in humans. Unconventional myosin motors are central to the assembly and shaping of stereocilia architecture. A sub-group of myosin motors with MyTH4-FERM domains (MYO7A, MYO15A) are particularly important in these processes, and hypothesized to act as transporters delivering structural and actin-regulatory cargos, in addition to generating force and tension. In this review, we summarize existing evidence for how MYO7A and MYO15A operate and how their dysfunction leads to stereocilia pathology. We further highlight emerging properties of the MyTH4/FERM myosin family and speculate how these new functions might contribute towards the acquisition and maintenance of mechano-sensitivity.
Collapse
Affiliation(s)
- Zane G Moreland
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA; Myology Institute, University of Florida, Gainesville, FL, 32610, USA; Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, 32610, USA
| | - Jonathan E Bird
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA; Myology Institute, University of Florida, Gainesville, FL, 32610, USA.
| |
Collapse
|
6
|
Hearing Features and Cochlear Implantation Outcomes in Patients With PathogenicMYO15AVariants: a Multicenter Observational Study. Ear Hear 2022; 43:1198-1207. [DOI: 10.1097/aud.0000000000001171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
7
|
Nasrniya S, Miar P, Narrei S, Sepehrnejad M, Nilforoush MH, Abtahi H, Tabatabaiefar MA. Whole-Exome Sequencing Identifies a Recurrent Small In-Frame Deletion in MYO15A Causing Autosomal Recessive Nonsyndromic Hearing Loss in 3 Iranian Pedigrees. Lab Med 2021; 53:111-122. [PMID: 34388253 DOI: 10.1093/labmed/lmab047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Hearing loss (HL) is the most prevalent and genetically heterogeneous sensory disabilities in humans throughout the world. METHODS In this study, we used whole-exome sequencing (WES) to determine the variant causing autosomal recessive nonsyndromic hearing loss (ARNSHL) segregating in 3 separate Iranian consanguineous families (with 3 different ethnicities: Azeri, Persian, and Lur), followed by cosegregation analysis, computational analysis, and structural modeling using the I-TASSER (Iterative Threading ASSEmbly Refinement) server. Also, we used speech-perception tests to measure cochlear implant (CI) performance in patients. RESULTS One small in-frame deletion variant (MYO15A c.8309_8311del (p.Glu2770del)), resulting in deletion of a single amino-acid residue was identified. We found it to be cosegregating with the disease in the studied families. We provide some evidence suggesting the pathogenesis of this variant in HL based on the American College of Medical Genetics (ACMG) and Genomics guidelines. Evaluation of auditory and speech performance indicated favorable outcome after cochlear implantation in our patients. CONCLUSIONS The findings of this study demonstrate the utility of WES in genetic diagnostics of HL.
Collapse
Affiliation(s)
- Samane Nasrniya
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Paniz Miar
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sina Narrei
- Erythron Pathobiology and Genetics lab, Isfahan, Iran
| | - Mahsa Sepehrnejad
- Department of Audiology, School of Rehabilitation Sciences, Isfahan University of Medical Sciences University of Medical Sciences, Isfahan, Iran
| | - Mohammad Hussein Nilforoush
- Department of Audiology, School of Rehabilitation Sciences, Isfahan University of Medical Sciences University of Medical Sciences, Isfahan, Iran
| | - Hamidreza Abtahi
- Department of Otolaryngology, Al-Zahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.,Department of Ear, Nose & Throat, and Head & Neck Surgery, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Amin Tabatabaiefar
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.,Erythron Pathobiology and Genetics lab, Isfahan, Iran.,Pediatric Inherited Diseases Research Center, Research Institute for Primordial Prevention of Noncommunicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
8
|
Miyoshi T, Belyantseva IA, Kitajiri SI, Miyajima H, Nishio SY, Usami SI, Kim BJ, Choi BY, Omori K, Shroff H, Friedman TB. Human deafness-associated variants alter the dynamics of key molecules in hair cell stereocilia F-actin cores. Hum Genet 2021; 141:363-382. [PMID: 34232383 DOI: 10.1007/s00439-021-02304-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/15/2021] [Indexed: 12/16/2022]
Abstract
Stereocilia protrude up to 100 µm from the apical surface of vertebrate inner ear hair cells and are packed with cross-linked filamentous actin (F-actin). They function as mechanical switches to convert sound vibration into electrochemical neuronal signals transmitted to the brain. Several genes encode molecular components of stereocilia including actin monomers, actin regulatory and bundling proteins, motor proteins and the proteins of the mechanotransduction complex. A stereocilium F-actin core is a dynamic system, which is continuously being remodeled while maintaining an outwardly stable architecture under the regulation of F-actin barbed-end cappers, severing proteins and crosslinkers. The F-actin cores of stereocilia also provide a pathway for motor proteins to transport cargos including components of tip-link densities, scaffolding proteins and actin regulatory proteins. Deficiencies and mutations of stereocilia components that disturb this "dynamic equilibrium" in stereocilia can induce morphological changes and disrupt mechanotransduction causing sensorineural hearing loss, best studied in mouse and zebrafish models. Currently, at least 23 genes, associated with human syndromic and nonsyndromic hearing loss, encode proteins involved in the development and maintenance of stereocilia F-actin cores. However, it is challenging to predict how variants associated with sensorineural hearing loss segregating in families affect protein function. Here, we review the functions of several molecular components of stereocilia F-actin cores and provide new data from our experimental approach to directly evaluate the pathogenicity and functional impact of reported and novel variants of DIAPH1 in autosomal-dominant DFNA1 hearing loss using single-molecule fluorescence microscopy.
Collapse
Affiliation(s)
- Takushi Miyoshi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, Room 1F-143A, Bethesda, MD, 20892, USA. .,Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan.
| | - Inna A Belyantseva
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, Room 1F-143A, Bethesda, MD, 20892, USA
| | - Shin-Ichiro Kitajiri
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 390-8621, Matsumoto, Japan
| | - Hiroki Miyajima
- Department of Otolaryngology, Shinshu University School of Medicine, Matsumoto, 390-8621, Japan.,Department of Otolaryngology, Aizawa Hospital, Matsumoto, 390-8510, Japan
| | - Shin-Ya Nishio
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 390-8621, Matsumoto, Japan
| | - Shin-Ichi Usami
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 390-8621, Matsumoto, Japan
| | - Bong Jik Kim
- Department of Otolaryngology-Head and Neck Surgery, Chungnam National University College of Medicine, Chungnam National University Sejong Hospital, Sejong, 30099, South Korea.,Brain Research Institute, Chungnam National University College of Medicine, Daejeon, 35015, South Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, Seongnam, 13620, South Korea
| | - Koichi Omori
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Hari Shroff
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, Room 1F-143A, Bethesda, MD, 20892, USA
| |
Collapse
|
9
|
Hirsch Y, Tangshewinsirikul C, Booth KT, Azaiez H, Yefet D, Quint A, Weiden T, Brownstein Z, Macarov M, Davidov B, Pappas J, Rabin R, Kenna MA, Oza AM, Lafferty K, Amr SS, Rehm HL, Kolbe DL, Frees K, Nishimura C, Luo M, Farra C, Morton CC, Scher SY, Ekstein J, Avraham KB, Smith RJH, Shen J. A synonymous variant in MYO15A enriched in the Ashkenazi Jewish population causes autosomal recessive hearing loss due to abnormal splicing. Eur J Hum Genet 2021; 29:988-997. [PMID: 33398081 PMCID: PMC8187401 DOI: 10.1038/s41431-020-00790-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 11/04/2020] [Accepted: 11/25/2020] [Indexed: 11/09/2022] Open
Abstract
Nonsyndromic hearing loss is genetically heterogeneous. Despite comprehensive genetic testing, many cases remain unsolved because the clinical significance of identified variants is uncertain or because biallelic pathogenic variants are not identified for presumed autosomal recessive cases. Common synonymous variants are often disregarded. Determining the pathogenicity of synonymous variants may improve genetic diagnosis. We report a synonymous variant c.9861 C > T/p.(Gly3287=) in MYO15A in homozygosity or compound heterozygosity with another pathogenic or likely pathogenic MYO15A variant in 10 unrelated families with nonsyndromic sensorineural hearing loss. Biallelic variants in MYO15A were identified in 21 affected and were absent in 22 unaffected siblings. A mini-gene assay confirms that the synonymous variant leads to abnormal splicing. The variant is enriched in the Ashkenazi Jewish population. Individuals carrying biallelic variants involving c.9861 C > T often exhibit progressive post-lingual hearing loss distinct from the congenital profound deafness typically associated with biallelic loss-of-function MYO15A variants. This study establishes the pathogenicity of the c.9861 C > T variant in MYO15A and expands the phenotypic spectrum of MYO15A-related hearing loss. Our work also highlights the importance of multicenter collaboration and data sharing to establish the pathogenicity of a relatively common synonymous variant for improved diagnosis and management of hearing loss.
Collapse
Affiliation(s)
- Yoel Hirsch
- Dor Yeshorim, Committee for Prevention of Jewish Genetic Diseases, Brooklyn, NY, 11211, USA
| | - Chayada Tangshewinsirikul
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, 10400, Thailand
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Kevin T Booth
- Molecular Otolaryngology and Renal Research Laboratories, The University of Iowa, Iowa City, IA, 52242, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA, 02215, USA
| | - Hela Azaiez
- Molecular Otolaryngology and Renal Research Laboratories, The University of Iowa, Iowa City, IA, 52242, USA
| | - Devorah Yefet
- Dor Yeshorim, Committee for Prevention of Jewish Genetic Diseases, Jerusalem, 91506, Israel
| | - Adina Quint
- Dor Yeshorim, Committee for Prevention of Jewish Genetic Diseases, Jerusalem, 91506, Israel
| | - Tzvi Weiden
- Dor Yeshorim, Committee for Prevention of Jewish Genetic Diseases, Jerusalem, 91506, Israel
| | - Zippora Brownstein
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Michal Macarov
- Department of Genetics and Metabolic Diseases, Hadassah Medical Center, Jerusalem, 91120, Israel
| | - Bella Davidov
- Department of Medical Genetics, Rabin Medical Center, Petah Tikva, 49100, Israel
| | - John Pappas
- Department of Pediatrics, New York University School of Medicine, New York, NY, 10016, USA
| | - Rachel Rabin
- Department of Pediatrics, New York University School of Medicine, New York, NY, 10016, USA
| | - Margaret A Kenna
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Medical School Center for Hereditary Deafness, Boston, MA, 02115, USA
| | - Andrea M Oza
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, MA, 02139, USA
| | - Katherine Lafferty
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, MA, 02139, USA
- Maine Medical Center, Scarborough, ME, 04074, USA
| | - Sami S Amr
- Harvard Medical School Center for Hereditary Deafness, Boston, MA, 02115, USA
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, MA, 02139, USA
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Heidi L Rehm
- Harvard Medical School Center for Hereditary Deafness, Boston, MA, 02115, USA
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, MA, 02139, USA
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Diana L Kolbe
- Molecular Otolaryngology and Renal Research Laboratories, The University of Iowa, Iowa City, IA, 52242, USA
| | - Kathy Frees
- Molecular Otolaryngology and Renal Research Laboratories, The University of Iowa, Iowa City, IA, 52242, USA
| | - Carla Nishimura
- Molecular Otolaryngology and Renal Research Laboratories, The University of Iowa, Iowa City, IA, 52242, USA
| | - Minjie Luo
- The Children's Hospital of Philadelphia, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA
| | - Chantal Farra
- Medical Genetics Unit, American University of Beirut Medical Center, AUBMC, 1107 2020, Beirut, Lebanon
| | - Cynthia C Morton
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Medical School Center for Hereditary Deafness, Boston, MA, 02115, USA
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Manchester Centre for Audiology and Deafness, School of Health Sciences, The University of Manchester, Manchester, M13 9PL, UK
| | - Sholem Y Scher
- Dor Yeshorim, Committee for Prevention of Jewish Genetic Diseases, Brooklyn, NY, 11211, USA
| | - Josef Ekstein
- Dor Yeshorim, Committee for Prevention of Jewish Genetic Diseases, Brooklyn, NY, 11211, USA
| | - Karen B Avraham
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel.
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, The University of Iowa, Iowa City, IA, 52242, USA.
| | - Jun Shen
- Harvard Medical School Center for Hereditary Deafness, Boston, MA, 02115, USA.
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, MA, 02139, USA.
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
| |
Collapse
|
10
|
Abstract
Filopodia, microvilli and stereocilia represent an important group of plasma membrane protrusions. These specialized projections are supported by parallel bundles of actin filaments and have critical roles in sensing the external environment, increasing cell surface area, and acting as mechanosensors. While actin-associated proteins are essential for actin-filament elongation and bundling in these protrusions, myosin motors have a surprising role in the formation and extension of filopodia and stereocilia and in the organization of microvilli. Actin regulators and specific myosins collaborate in controlling the length of these structures. Myosins can transport cargoes along the length of these protrusions, and, in the case of stereocilia and microvilli, interactions with adaptors and cargoes can also serve to anchor adhesion receptors to the actin-rich core via functionally conserved motor-adaptor complexes. This review highlights recent progress in understanding the diverse roles myosins play in filopodia, microvilli and stereocilia.
Collapse
Affiliation(s)
- Anne Houdusse
- Structural Motility, Institut Curie, Paris Université Sciences et Lettres, Sorbonne Université, CNRS UMR144, 75005 Paris, France.
| | - Margaret A Titus
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
11
|
Identification of Novel Compound Heterozygous MYO15A Mutations in Two Chinese Families with Autosomal Recessive Nonsyndromic Hearing Loss. Neural Plast 2021; 2021:9957712. [PMID: 34093702 PMCID: PMC8140830 DOI: 10.1155/2021/9957712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/14/2021] [Accepted: 05/04/2021] [Indexed: 11/17/2022] Open
Abstract
Congenital deafness is one of the most common causes of disability in humans, and more than half of cases are caused by genetic factors. Mutations of the MYO15A gene are the third most common cause of hereditary hearing loss. Using next-generation sequencing combined with auditory tests, two novel compound heterozygous variants c.2802_2812del/c.5681T>C and c.5681T>C/c.6340G>A in the MYO15A gene were identified in probands from two irrelevant Chinese families. Auditory phenotypes of the probands are consistent with the previously reported for recessive variants in the MYO15A gene. The two novel variants, c.2802_2812del and c.5681T>C, were identified as deleterious mutations by bioinformatics analysis. Our findings extend the MYO15A gene mutation spectrum and provide more information for rapid and precise molecular diagnosis of congenital deafness.
Collapse
|
12
|
Dianatpour M, Smith E, Hashemi SB, Farazifard MA, Nezafat N, Razban V, Mani A. Identification of homozygous mutations for hearing loss. Gene 2021; 778:145464. [PMID: 33524517 DOI: 10.1016/j.gene.2021.145464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 01/19/2021] [Accepted: 01/22/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hearing loss is the most common sensory disorder worldwide, affecting about 1 out of every 1000 newborns. The disease has major genetic components, and can be inherited as a single gene disorder either in autosomal dominant or recessive fashions. Due to the high rate of consanguineous unions, Iran has one of the highest prevalence of autosomal recessive nonsyndromic deafness (ARNSD) in the world. METHODS We carried out a genetic screening of ten Iranian kindreds with more than one offspring affected by ARNSD caused by consanguineous unions. Sanger sequencing and whole exome sequencing together with in silico 3D structure modeling and protein stability prediction were used to identify the underlying disease causing genes. CONCLUSION We identified the causes of deafness in all 10 kindred. In six kindreds homozygous mutations were identified in GJB2 gene by Sanger sequencing. By using whole exome sequencing (WES), a homozygous missense mutation was identified in ESRRB gene as the first ever reported disease gene in Iran. Also two novel homozygous frameshift and missense mutations were identified in MYO15A gene and one previously reported mutation in TMC1 gene in three independent kindred. Our study shows the efficacy of WES for unraveling new pathogenic mutations in ARNSD patients and expands the spectrum of genes contributing to ARNSD in the Iranian population. The findings of our study can facilitate future genetic screening of patients with ARNSD , early screening and optimal design of novel therapeutics.
Collapse
Affiliation(s)
- Mehdi Dianatpour
- Department of Medical Genetic, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; Stem Cells Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Emily Smith
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University, School of Medicine, New Haven, CT, United States.
| | - Seyed Basir Hashemi
- Department of Otolaryngology, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad A Farazifard
- Department of Medical Genetic, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Navid Nezafat
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Pharmaceutical Biotechnology, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Vahid Razban
- Stem Cells Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Molecular Medicine, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Arya Mani
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University, School of Medicine, New Haven, CT, United States.
| |
Collapse
|
13
|
Hashemzadeh-Chaleshtori M, Azadegan-Dehkordi F, Ashrafi K, Mobini G, Yazdanpanahi N, Shirzad M, Farrokhi E. Detection of two pathogenesis previously unreported myosin xva pathogenic variants in two large Iranian pedigrees with autosomal recessive nonsyndromic hearing loss. INDIAN JOURNAL OF OTOLOGY 2021. [DOI: 10.4103/indianjotol.indianjotol_73_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
14
|
Jiang F, Takagi Y, Shams A, Heissler SM, Friedman TB, Sellers JR, Bird JE. The ATPase mechanism of myosin 15, the molecular motor mutated in DFNB3 human deafness. J Biol Chem 2021; 296:100243. [PMID: 33372036 PMCID: PMC7948958 DOI: 10.1074/jbc.ra120.014903] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 12/23/2020] [Accepted: 12/28/2020] [Indexed: 11/18/2022] Open
Abstract
Cochlear hair cells each possess an exquisite bundle of actin-based stereocilia that detect sound. Unconventional myosin 15 (MYO15) traffics and delivers critical molecules required for stereocilia development and thus is essential for building the mechanosensory hair bundle. Mutations in the human MYO15A gene interfere with stereocilia trafficking and cause hereditary hearing loss, DFNB3, but the impact of these mutations is not known, as MYO15 itself is poorly characterized. To learn more, we performed a kinetic study of the ATPase motor domain to characterize its mechanochemical cycle. Using the baculovirus-Sf9 system, we purified a recombinant minimal motor domain (S1) by coexpressing the mouse MYO15 ATPase, essential and regulatory light chains that bind its IQ domains, and UNC45 and HSP90A chaperones required for correct folding of the ATPase. MYO15 purified with either UNC45A or UNC45B coexpression had similar ATPase activities (kcat = ∼ 6 s-1 at 20 °C). Using stopped-flow and quenched-flow transient kinetic analyses, we measured the major rate constants describing the ATPase cycle, including ATP, ADP, and actin binding; hydrolysis; and phosphate release. Actin-attached ADP release was the slowest measured transition (∼12 s-1 at 20 °C), although this did not rate-limit the ATPase cycle. The kinetic analysis shows the MYO15 motor domain has a moderate duty ratio (∼0.5) and weak thermodynamic coupling between ADP and actin binding. These findings are consistent with MYO15 being kinetically adapted for processive motility when oligomerized. Our kinetic characterization enables future studies into how deafness-causing mutations affect MYO15 and disrupt stereocilia trafficking necessary for hearing.
Collapse
Affiliation(s)
- Fangfang Jiang
- Department of Pharmacology and Therapeutics, and the Myology Institute, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Yasuharu Takagi
- Laboratory of Molecular Physiology, Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Arik Shams
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, USA
| | - Sarah M Heissler
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, USA
| | - James R Sellers
- Laboratory of Molecular Physiology, Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Jonathan E Bird
- Department of Pharmacology and Therapeutics, and the Myology Institute, University of Florida College of Medicine, Gainesville, Florida, USA.
| |
Collapse
|
15
|
Abstract
Myosins constitute a superfamily of actin-based molecular motor proteins that mediates a variety of cellular activities including muscle contraction, cell migration, intracellular transport, the formation of membrane projections, cell adhesion, and cell signaling. The 12 myosin classes that are expressed in humans share sequence similarities especially in the N-terminal motor domain; however, their enzymatic activities, regulation, ability to dimerize, binding partners, and cellular functions differ. It is becoming increasingly apparent that defects in myosins are associated with diseases including cardiomyopathies, colitis, glomerulosclerosis, neurological defects, cancer, blindness, and deafness. Here, we review the current state of knowledge regarding myosins and disease.
Collapse
|
16
|
Genomic analysis of inherited hearing loss in the Palestinian population. Proc Natl Acad Sci U S A 2020; 117:20070-20076. [PMID: 32747562 DOI: 10.1073/pnas.2009628117] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The genetic characterization of a common phenotype for an entire population reveals both the causes of that phenotype for that place and the power of family-based, population-wide genomic analysis for gene and mutation discovery. We characterized the genetics of hearing loss throughout the Palestinian population, enrolling 2,198 participants from 491 families from all parts of the West Bank and Gaza. In Palestinian families with no prior history of hearing loss, we estimate that 56% of hearing loss is genetic and 44% is not genetic. For the great majority (87%) of families with inherited hearing loss, panel-based genomic DNA sequencing, followed by segregation analysis of large kindreds and transcriptional analysis of participant RNA, enabled identification of the causal genes and mutations, including at distant noncoding sites. Genetic heterogeneity of hearing loss was striking with respect to both genes and alleles: The 337 solved families harbored 143 different mutations in 48 different genes. For one in four solved families, a transcription-altering mutation was the responsible allele. Many of these mutations were cryptic, either exonic alterations of splice enhancers or silencers or deeply intronic events. Experimentally calibrated in silico analysis of transcriptional effects yielded inferences of high confidence for effects on splicing even of mutations in genes not expressed in accessible tissue. Most (58%) of all hearing loss in the population was attributable to consanguinity. Given the ongoing decline in consanguineous marriage, inherited hearing loss will likely be much rarer in the next generation.
Collapse
|
17
|
Compound Heterozygous Mutations in TMC1 and MYO15A Are Associated with Autosomal Recessive Nonsyndromic Hearing Loss in Two Chinese Han Families. Neural Plast 2020; 2020:8872185. [PMID: 32802042 PMCID: PMC7416276 DOI: 10.1155/2020/8872185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/12/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022] Open
Abstract
Genetic hearing loss is a common sensory disorder, and its cause is highly heterogeneous. In this study, by targeted next-generation sequencing of 414 known deafness genes, we identified compound heterozygous mutations p.R34X/p.M413T in TMC1 and p.S3417del/p.R1407T in MYO15A in two recessive Chinese Han deaf families. Intrafamilial cosegregation of the mutations with the hearing phenotype was confirmed in both families by the Sanger sequencing. Auditory features of the affected individuals are consistent with that previously reported for recessive mutations in TMC1 and MYO15A. The two novel mutations identified in this study, p.M413T in TMC1 and p.R1407T in MYO15A, are classified as likely pathogenic according to the guidelines of ACMG. Our study expanded the mutation spectrums of TMC1 and MYO15A and illustrated that genotype-phenotype correlation in combination with next-generation sequencing may improve the accuracy for genetic diagnosis of deafness.
Collapse
|
18
|
Targeted Next-Generation Sequencing Identified Compound Heterozygous Mutations in MYO15A as the Probable Cause of Nonsyndromic Deafness in a Chinese Han Family. Neural Plast 2020; 2020:6350479. [PMID: 32617096 PMCID: PMC7313121 DOI: 10.1155/2020/6350479] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/10/2020] [Accepted: 05/29/2020] [Indexed: 12/02/2022] Open
Abstract
Hearing loss is a highly heterogeneous disorder, with more than 60% of congenital cases caused by genetic factors. This study is aimed at identifying the genetic cause of congenital hearing loss in a Chinese Han family. Auditory evaluation before and after cochlear implantation and targeted next-generation sequencing of 140 deafness-related genes were performed for the deaf proband. Compound heterozygous mutations c.3658_3662del (p. E1221Wfs∗23) and c.6177+1G>T were identified in MYO15A as the only candidate pathogenic mutations cosegregated with the hearing loss in this family. These two variants were absent in 200 normal-hearing Chinese Hans and were classified as likely pathogenic and pathogenic, respectively, based on the ACMG guideline. Our study further expanded the mutation spectrum of MYO15A as the c.3658_3662del mutation is novel and confirmed that deaf patients with recessive MYO15A mutations have a good outcome for cochlear implantation.
Collapse
|
19
|
|
20
|
Mechanotransduction-Dependent Control of Stereocilia Dimensions and Row Identity in Inner Hair Cells. Curr Biol 2020; 30:442-454.e7. [PMID: 31902726 DOI: 10.1016/j.cub.2019.11.076] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/08/2019] [Accepted: 11/26/2019] [Indexed: 02/07/2023]
Abstract
Actin-rich structures, like stereocilia and microvilli, are assembled with precise control of length, diameter, and relative spacing. By quantifying actin-core dimensions of stereocilia from phalloidin-labeled mouse cochleas, we demonstrated that inner hair cell stereocilia developed in specific stages, where a widening phase is sandwiched between two lengthening phases. Moreover, widening of the second-tallest stereocilia rank (row 2) occurred simultaneously with the appearance of mechanotransduction. Correspondingly, Tmc1KO/KO;Tmc2KO/KO or TmieKO/KO hair cells, which lack transduction, have significantly altered stereocilia lengths and diameters, including a narrowed row 2. EPS8 and the short splice isoform of MYO15A, identity markers for mature row 1 (the tallest row), lost their row exclusivity in transduction mutants. GNAI3, another member of the mature row 1 complex, accumulated at mutant row 1 tips at considerably lower levels than in wild-type bundles. Alterations in stereocilia dimensions and in EPS8 distribution seen in transduction mutants were mimicked by block of transduction channels of cochlear explants in culture. In addition, proteins normally concentrated at mature row 2 tips were also distributed differently in transduction mutants; the heterodimeric capping protein subunit CAPZB and its partner TWF2 never concentrated at row 2 tips like they do in wild-type bundles. The altered distribution of marker proteins in transduction mutants was accompanied by increased variability in stereocilia length. Transduction channels thus specify and maintain row identity, control addition of new actin filaments to increase stereocilia diameter, and coordinate stereocilia height within rows.
Collapse
|
21
|
Friedman TB, Belyantseva IA, Frolenkov GI. Myosins and Hearing. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1239:317-330. [DOI: 10.1007/978-3-030-38062-5_13] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
22
|
Identification of a novel homozygous mutation in the MYO15A gene in a Kazakh family with non-syndromic hearing loss. Int J Pediatr Otorhinolaryngol 2019; 125:128-132. [PMID: 31301639 DOI: 10.1016/j.ijporl.2019.06.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 06/16/2019] [Accepted: 06/16/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Millions of people around the world are plagued by hearing loss. More than 50% of congenital or pre-lingual deafness is associated with genetic factors and has highly genetic heterogeneity. To date, although hundreds of genes have been found to be implicated in non-syndromic deafness, there are still lots of genes or loci that we need to verify. METHODS In this study, we performed target sequencing and Sanger sequencing in a Kazakh consanguineous family with autosomal recessive non-syndromic hearing loss. Following that, functional and structural studies predicted the pathogenic effect of novel mutations by use of the online tools. RESULTS We identified a novel homozygous mutation p.R3191C in MYO15A gene causing deafness in this family. The mutation p.R3191C co-segregated with the disease phenotype in this family and was not present in any public databases. Automatic tools predict that the novel mutation makes a great impact on the function and structure of MYO15A protein. CONCLUSIONS This is a novel mutation of MYO15A causing deafness and also the first report of MYO15A mutations causing deafness in the Kazakh families. This finding expanded the spectrum of MYO15A mutations, making it more precise for future genetic diagnosis in patients with deafness.
Collapse
|
23
|
Akbariazar E, Vahabi A, Abdi Rad I. Report of a Novel Splicing Mutation in the MYO15A Gene in a Patient With Sensorineural Hearing Loss and Spectrum of the MYO15A Mutations. CLINICAL MEDICINE INSIGHTS-CASE REPORTS 2019; 12:1179547619871907. [PMID: 31579092 PMCID: PMC6757496 DOI: 10.1177/1179547619871907] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 07/30/2019] [Indexed: 12/29/2022]
Abstract
Introduction Autosomal recessive non-syndromic hearing loss (ARNSHL) is a genetically heterogeneous sensorineural disorder with an approximate incidence of 1.4:1000 in neonates. Mutations in more than 60 genes including the MYO15A gene has been reported in patients affected with ARNSHL. In the present study, we report a novel MYO15A mutation identified by clinical exome sequencing and confirmed by Sanger sequencing in a consanguineous Iranian family with ARNSHL. Case presentation A 22-year-old woman with congenital non-syndromic sensorineural hearing loss referred to our medical genetic center. Her parents were consanguineous with F = 1/16 (first cousin), and clinical examination of the patient exclude dysmorphic features. Sanger sequencing of GJB2 and GJB6 genes, which are the most common causes of ARNSHL, was negative. Then she underwent clinical exome sequencing. Outcome We found a novel homozygote variant (c.9611_9612+8delTGGTGAGCAT) in the MYO15A gene which creates a shift in the reading frame starting at codon 3204. This variant was confirmed by Sanger sequencing in the patient and also in her parents who were heterozygous. Discussion The present results suggest that the homozygous MYO15A (c.9611_9612+8delTGGTGAGCAT) variant is a pathogenic mutation and to the best of our knowledge, this mutation has not been reported in any database.
Collapse
Affiliation(s)
- Elinaz Akbariazar
- Department of Genetics, Urmia University of Medical Sciences, Urmia, Iran
| | - Ali Vahabi
- Department of Genetics, Urmia University of Medical Sciences, Urmia, Iran
| | - Isa Abdi Rad
- Department of Genetics, Urmia University of Medical Sciences, Urmia, Iran.,Cellular and Molecular Research Center, Urmia University of Medical Sciences, Urmia, Iran
| |
Collapse
|
24
|
Farries G, Gough KF, Parnell AC, McGivney BA, McGivney CL, McGettigan PA, MacHugh DE, Katz LM, Hill EW. Analysis of genetic variation contributing to measured speed in Thoroughbreds identifies genomic regions involved in the transcriptional response to exercise. Anim Genet 2019; 50:670-685. [PMID: 31508842 DOI: 10.1111/age.12848] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2019] [Indexed: 12/31/2022]
Abstract
Despite strong selection for athletic traits in Thoroughbred horses, there is marked variation in speed and aptitude for racing performance within the breed. Using global positioning system monitoring during exercise training, we measured speed variables and temporal changes in speed with age to derive phenotypes for GWAS. The aim of the study was to test the hypothesis that genetic variation contributes to variation in end-point physiological traits, in this case galloping speed measured during field exercise tests. Standardisation of field-measured phenotypes was attempted by assessing horses exercised on the same gallop track and managed under similar conditions by a single trainer. PCA of six key speed indices captured 73.9% of the variation with principal component 1 (PC1). Verifying the utility of the phenotype, we observed that PC1 (median) in 2-year-old horses was significantly different among elite, non-elite and unraced horses (P < 0.001) and the temporal change with age in PC1 varied among horses with different myostatin (MSTN) g.66493737C>T SNP genotypes. A GWAS for PC1 in 2-year-old horses (n = 122) identified four SNPs reaching the suggestive threshold for association (P < 4.80 × 10-5 ), defining a 1.09 Mb candidate region on ECA8 containing the myosin XVIIIB (MYO18B) gene. In a GWAS for temporal change in PC1 with age (n = 168), five SNPs reached the suggestive threshold for association and defined candidate regions on ECA2 and ECA11. Both regions contained genes that are significantly differentially expressed in equine skeletal muscle in response to acute exercise and training stimuli, including MYO18A. As MYO18A plays a regulatory role in the skeletal muscle response to exercise, the identified genomic variation proximal to the myosin family genes may be important for the regulation of the response to exercise and training.
Collapse
Affiliation(s)
- G Farries
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - K F Gough
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - A C Parnell
- Insight Centre for Data Analytics, Hamilton Institute, Maynooth University, Kildare, W23 F2H6, Ireland
| | - B A McGivney
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland.,Plusvital Ltd, Dun Laoghaire Industrial Estate, Pottery Road, Dublin, A96 KW29, Ireland
| | - C L McGivney
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - P A McGettigan
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - D E MacHugh
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland.,UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - L M Katz
- UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - E W Hill
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland.,Plusvital Ltd, Dun Laoghaire Industrial Estate, Pottery Road, Dublin, A96 KW29, Ireland
| |
Collapse
|
25
|
Chakchouk I, Zhang D, Zhang Z, Francioli LC, Santos-Cortez RLP, Schrauwen I, Leal SM. Disparities in discovery of pathogenic variants for autosomal recessive non-syndromic hearing impairment by ancestry. Eur J Hum Genet 2019; 27:1456-1465. [PMID: 31053783 PMCID: PMC6777454 DOI: 10.1038/s41431-019-0417-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 04/01/2019] [Accepted: 04/16/2019] [Indexed: 12/22/2022] Open
Abstract
Hearing impairment (HI) is characterized by extensive genetic heterogeneity. To determine the population-specific contribution of known autosomal recessive nonsyndromic (ARNS)HI genes and variants to HI etiology; pathogenic and likely pathogenic (PLP) ARNSHI variants were selected from ClinVar and the Deafness Variation Database and their frequencies were obtained from gnomAD for seven populations. ARNSHI prevalence due to PLP variants varies greatly by population ranging from 96.9 affected per 100,000 individuals for Ashkenazi Jews to 5.2 affected per 100,000 individuals for Africans/African Americans. For Europeans, Finns have the lowest prevalence due to ARNSHI PLP variants with 9.5 affected per 100,000 individuals. For East Asians, Latinos, non-Finish Europeans, and South Asians, ARNSHI prevalence due to PLP variants ranges from 17.1 to 33.7 affected per 100,000 individuals. ARNSHI variants that were previously reported in a single ancestry or family were observed in additional populations, e.g., USH1C p.(Q723*) reported in a Chinese family was the most prevalent pathogenic variant observed in gnomAD for African/African Americans. Variability between populations is due to how extensively ARNSHI has been studied, ARNSHI prevalence and ancestry specific ARNSHI variant architecture which is impacted by population history. Our study demonstrates that additional gene and variant discovery studies are necessary for all populations and particularly for individuals of African ancestry.
Collapse
Affiliation(s)
- Imen Chakchouk
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Di Zhang
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Zhihui Zhang
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Center for Statistical Genetics, Department of Neurology, Gertrude H. Sergievsky Center, Columbia University Medical Center, New York, NY, USA
| | - Laurent C Francioli
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA, USA
- Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA
| | | | - Isabelle Schrauwen
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Center for Statistical Genetics, Department of Neurology, Gertrude H. Sergievsky Center, Columbia University Medical Center, New York, NY, USA
| | - Suzanne M Leal
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
- Center for Statistical Genetics, Department of Neurology, Gertrude H. Sergievsky Center, Columbia University Medical Center, New York, NY, USA.
| |
Collapse
|
26
|
Zhang J, Guan J, Wang H, Yin L, Wang D, Zhao L, Zhou H, Wang Q. Genotype-phenotype correlation analysis of MYO15A variants in autosomal recessive non-syndromic hearing loss. BMC MEDICAL GENETICS 2019; 20:60. [PMID: 30953472 PMCID: PMC6451310 DOI: 10.1186/s12881-019-0790-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Accepted: 03/20/2019] [Indexed: 12/13/2022]
Abstract
Background MYO15A variants are responsible for human non-syndromic autosomal recessive deafness (DFNB3). The majority of MYO15A variants are associated with a congenital severe-to-profound hearing loss phenotype, except for MYO15A variants in exon 2, which cause a milder auditory phenotype, suggesting a genotype-phenotype correlation of MYO15A. However, MYO15A variants not in exon 2 related to a milder phenotype have also been reported, indicating that the genotype-phenotype correlation of MYO15A is complicated. This study aimed to provide more cases of MYO15A variation with diverse phenotypes to analyse this complex correlation. Methods Fifteen Chinese autosomal recessive non-syndromic hearing loss (ARNSHL) individuals with MYO15A variants (8 males and 7 females) from 14 unrelated families, identified by targeted gene capture of 127 known candidate deafness genes, were recruited. Additionally, we conducted a review of the literature to further analyses all reported MYO15A genotype-phenotype relationships worldwide. Results We identified 16 novel variants and 12 reported pathogenic MYO15A variants in 15 patients, two of which presented with a milder phenotype. Interestingly, one of these cases carried two reported pathogenic variants in exon 2, while the other carried two novel variants not in exon 2. Based on our literature review, MYO15A genotype-phenotype correlation analysis showed that almost all domains were reported to be correlated with a milder phenotype. However, variants in the N-terminal domain were more likely to cause a milder phenotype. Using next-generation sequencing (NGS), we also found that the number of known MYO15A variants with milder phenotypes in Southeast Asia has increased in recent years. Conclusion Our work extended the MYO15A variant spectrum, enriched our knowledge of auditory phenotypes, and tried to explore the genotype-phenotype correlation in different populations in order to investigate the cause of the complex MYO15A genotype-phenotype correlation. Electronic supplementary material The online version of this article (10.1186/s12881-019-0790-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Jing Zhang
- Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Medical School of Chinese PLA, 28 Fuxing Road, Beijing, 100853, China.,Department of Otolaryngology of Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Jing Guan
- Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Medical School of Chinese PLA, 28 Fuxing Road, Beijing, 100853, China.
| | - Hongyang Wang
- Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Medical School of Chinese PLA, 28 Fuxing Road, Beijing, 100853, China
| | | | - Dayong Wang
- Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Medical School of Chinese PLA, 28 Fuxing Road, Beijing, 100853, China
| | - Lidong Zhao
- Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Medical School of Chinese PLA, 28 Fuxing Road, Beijing, 100853, China
| | - Huifang Zhou
- Department of Otolaryngology of Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Qiuju Wang
- Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Medical School of Chinese PLA, 28 Fuxing Road, Beijing, 100853, China.
| |
Collapse
|
27
|
Fettiplace R, Nam JH. Tonotopy in calcium homeostasis and vulnerability of cochlear hair cells. Hear Res 2018; 376:11-21. [PMID: 30473131 DOI: 10.1016/j.heares.2018.11.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/05/2018] [Accepted: 11/08/2018] [Indexed: 12/18/2022]
Abstract
Ototoxicity, noise overstimulation, or aging, can all produce hearing loss with similar properties, in which outer hair cells (OHCs), principally those at the high-frequency base of the cochlea, are preferentially affected. We suggest that the differential vulnerability may partly arise from differences in Ca2+ balance among cochlear locations. Homeostasis is determined by three factors: Ca2+ influx mainly via mechanotransducer (MET) channels; buffering by calcium-binding proteins and organelles like mitochondria; and extrusion by the plasma membrane CaATPase pump. We review quantification of these parameters and use our experimentally-determined values to model changes in cytoplasmic and mitochondrial Ca2+ during Ca2+ influx through the MET channels. We suggest that, in OHCs, there are two distinct micro-compartments for Ca2+ handling, one in the hair bundle and the other in the cell soma. One conclusion of the modeling is that there is a tonotopic gradient in the ability of OHCs to handle the Ca2+ load, which correlates with their vulnerability to environmental challenges. High-frequency basal OHCs are the most susceptible because they have much larger MET currents and have smaller dimensions than low-frequency apical OHCs.
Collapse
Affiliation(s)
- Robert Fettiplace
- Department of Neuroscience, University of Wisconsin, Madison, WI, 53706, USA.
| | - Jong-Hoon Nam
- Departments of Mechanical Engineering and Biomedical Engineering, University of Rochester, Rochester, NY, 14627, USA
| |
Collapse
|
28
|
Three MYO15A Mutations Identified in One Chinese Family with Autosomal Recessive Nonsyndromic Hearing Loss. Neural Plast 2018; 2018:5898025. [PMID: 29849560 PMCID: PMC5907479 DOI: 10.1155/2018/5898025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/03/2017] [Indexed: 01/06/2023] Open
Abstract
Hearing impairment is one of the most common sensory disease, of which more than 50% is attributed to a genetic etiology. The goal of this research is to explore the genetic cause of a Chinese deafness pedigree who was excluded of GJB2, SLC26A4, or MtDNA12SrRNA variants. Three variants, c.3971C>A (p.A1324D), c.4011insA (p.Q1337Qfs∗22), and c.9690+1G>A, in the MYO15A gene were identified by targeted capture sequencing and Sanger sequencing, and the first two of them were novel. These variants were cosegregated with the disease in this family and absent in 200 normal hearing persons. They were concluded to be pathogenic mutations by phylogenetic analysis and structure modeling. Thus, the combined use of SNPScan assay and targeted capture sequencing is a high-efficiency and cost-effective screening procedure for hereditary hearing loss. Genetic counseling would be important for this family, and our finding would be a great supplement to the mutation spectrum of MYO15A.
Collapse
|
29
|
Chang MY, Lee C, Han JH, Kim MY, Park HR, Kim N, Park WY, Oh DY, Choi BY. Expansion of phenotypic spectrum of MYO15A pathogenic variants to include postlingual onset of progressive partial deafness. BMC MEDICAL GENETICS 2018; 19:29. [PMID: 29482514 PMCID: PMC6389081 DOI: 10.1186/s12881-018-0541-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 02/12/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND MYO15A variants, except those in the N-terminal domain, have been shown to be associated with congenital or pre-lingual severe-to-profound hearing loss (DFNB3), which ultimately requires cochlear implantation in early childhood. Recently, such variants have also been shown to possibly cause moderate-to-severe hearing loss. Herein, we also demonstrate that some MYO15A mutant alleles can cause postlingual onset of progressive partial deafness. METHODS Two multiplex Korean families (SB246 and SB224), manifesting postlingual, progressive, partial deafness in an autosomal recessive fashion, were recruited. Molecular genetics testing was performed in two different pipelines, in a parallel fashion, for the SB246 family: targeted exome sequencing (TES) of 129 known deafness genes from the proband and whole exome sequencing (WES) of all affected subjects. Only the former pipeline was performed for the SB224 family. Rigorous bioinformatics analyses encompassing structural variations were executed to investigate any causative variants. RESULTS In the SB246 family, two different molecular diagnostic pipelines provided exactly the same candidate variants: c.5504G > A (p.R1835H) in the motor domain and c.10245_10247delCTC (p.S3417del) in the FERM domain of MYO15A. In the SB224 family, c.9790C > T (p.Q3264X) and c.10263C > G (p.I3421M) in the FERM domain were detected as candidate variants. CONCLUSIONS Some recessive MYO15A variants can cause postlingual onset of progressive partial deafness. The phenotypic spectrum of DFNB3 should be extended to include such partial deafness. The mechanism for a milder phenotype could be due to the milder pathogenic potential from hypomorphic alleles of MYO15A or the presence of modifier genes. This merits further investigation.
Collapse
Affiliation(s)
- Mun Young Chang
- Department of Otorhinolaryngology-Head and Neck Surgery, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, 06973, Seoul, Republic of Korea
| | - Chung Lee
- Samsung Genome Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, 16419, Suwon, Republic of Korea
| | - Jin Hee Han
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Min Young Kim
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Hye-Rim Park
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Nayoung Kim
- Samsung Genome Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Republic of Korea
| | - Woong-Yang Park
- Samsung Genome Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, 16419, Suwon, Republic of Korea.,Department of Molecular Cell Biology, School of Medicine, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, 16419, Suwon, Republic of Korea
| | - Doo Yi Oh
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea. .,Wide River Institute of Immunology, Seoul National University College of Medicine, 101 Dabyeonbatgil, 25159, Hongcheon, Republic of Korea.
| |
Collapse
|
30
|
Salime S, Charif M, Bousfiha A, Elrharchi S, Bakhchane A, Charoute H, Kabine M, Snoussi K, Lenaers G, Barakat A. Homozygous mutations in PJVK and MYO15A genes associated with non-syndromic hearing loss in Moroccan families. Int J Pediatr Otorhinolaryngol 2017; 101:25-29. [PMID: 28964305 DOI: 10.1016/j.ijporl.2017.07.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/19/2017] [Accepted: 07/19/2017] [Indexed: 01/03/2023]
Abstract
OBJECTIVES Autosomal recessive non-syndromic hearing loss is a heterogeneous disorder and the most prevalent human genetic sensorineural defect. In this study, we investigated the geneticcause of sensorineural hearing loss in Moroccan patients and presented the importance of whole exome sequencing (WES) to identify candidate genes in two Moroccan families with profound deafness. METHODS After excluding mutations previously reported in Moroccan deaf patients, whole exome sequencing was performed and Sanger sequencing was used to validate mutations in these genes. RESULTS Our results disclosed the c.113_114insT (p.Lys41GlufsX8) and c.406C > T (p.Arg130X) homozygous mutations in PJVK and a homozygous c.5203C > T (p.Arg1735Trp) mutation in MYO15A, both genes responsible for non-syndromic recessive hearing loss DFNB59 and DFNB3, respectively. CONCLUSION We identified in Moroccan deaf patients two mutations in PJVK and one mutation in MYO15A described for the first time in association with non-syndromic recessive hearing loss. These results emphasize that whole exome sequencing is a powerful diagnostic strategy to identify pathogenic mutations in heterogeneous disorders with many various causative genes.
Collapse
Affiliation(s)
- Sara Salime
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco; Laboratoire de santé et Environnement, Université Hassan II, Faculté des Sciences Aïn Chock, Casablanca, Morocco
| | - Majida Charif
- MitoLab Team, CNRS UMR6015, INSERM U1083, Université d'Angers, CHU Bât IRIS/IBS, Rue des Capucins, 49933 Angerscedex 9, France
| | - Amale Bousfiha
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Soukaina Elrharchi
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Amina Bakhchane
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Hicham Charoute
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Mostafa Kabine
- Laboratoire de santé et Environnement, Université Hassan II, Faculté des Sciences Aïn Chock, Casablanca, Morocco
| | - Khalid Snoussi
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Guy Lenaers
- MitoLab Team, CNRS UMR6015, INSERM U1083, Université d'Angers, CHU Bât IRIS/IBS, Rue des Capucins, 49933 Angerscedex 9, France
| | - Abdelhamid Barakat
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco.
| |
Collapse
|
31
|
Parzefall T, Frohne A, Koenighofer M, Kirchnawy A, Streubel B, Schoefer C, Frei K, Lucas T. Whole-exome sequencing to identify the cause of congenital sensorineural hearing loss in carriers of a heterozygous GJB2 mutation. Eur Arch Otorhinolaryngol 2017; 274:3619-3625. [PMID: 28821934 PMCID: PMC5591807 DOI: 10.1007/s00405-017-4699-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 08/02/2017] [Indexed: 12/01/2022]
Abstract
Bi-allelic variations in the gap junction protein beta-2 (GJB2) gene cause up to 50% of cases of newborn hearing loss. Heterozygous pathogenic GJB2 variations are also fivefold overrepresented in idiopathic patient groups compared to the normal-hearing population. Whether hearing loss in this group is due to unidentified additional variations within GJB2 or variations in other deafness genes is unknown in most cases. Whole-exome sequencing offers an effective approach in the search for causative variations in patients with Mendelian diseases. In this prospective genetic cohort study, we initially investigated a family of Turkish origin suffering from congenital autosomal recessive hearing loss. An index patient and his normal-hearing father, both bearing a single heterozygous pathogenic c.262G>T (p.Ala88Ser) GJB2 transversion as well as the normal-hearing mother were investigated by means of whole-exome sequencing. Subsequently the genetic screening was extended to a hearing-impaired cohort of 24 families of Turkish origin. A homozygous missense c.5492G>T transversion (p.Gly1831Val) in the Myosin 15a gene, previously linked to deafness, was identified as causative in the index family. This very rare variant is not listed in any population in the Genome Aggregation Database. Subsequent screening of index patients from additional families of Turkish origin with recessive hearing loss identified the c.5492G>T variation in an additional family. Whole-exome sequencing may effectively identify the causes of idiopathic hearing loss in patients bearing heterozygous GJB2 variations.
Collapse
Affiliation(s)
- Thomas Parzefall
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria
| | - Alexandra Frohne
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Martin Koenighofer
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria
| | - Andreas Kirchnawy
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Berthold Streubel
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
| | - Christian Schoefer
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Klemens Frei
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria. .,Department of Otorhinolaryngology, Head and Neck Surgery, Vienna General Hospital (AKH), Waehringer Guertel 18-20, 1090, Vienna, Austria.
| | - Trevor Lucas
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
32
|
Defective Gpsm2/Gα i3 signalling disrupts stereocilia development and growth cone actin dynamics in Chudley-McCullough syndrome. Nat Commun 2017; 8:14907. [PMID: 28387217 PMCID: PMC5385604 DOI: 10.1038/ncomms14907] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 02/13/2017] [Indexed: 01/14/2023] Open
Abstract
Mutations in GPSM2 cause Chudley-McCullough syndrome (CMCS), an autosomal recessive neurological disorder characterized by early-onset sensorineural deafness and brain anomalies. Here, we show that mutation of the mouse orthologue of GPSM2 affects actin-rich stereocilia elongation in auditory and vestibular hair cells, causing deafness and balance defects. The G-protein subunit Gαi3, a well-documented partner of Gpsm2, participates in the elongation process, and its absence also causes hearing deficits. We show that Gpsm2 defines an ∼200 nm nanodomain at the tips of stereocilia and this localization requires the presence of Gαi3, myosin 15 and whirlin. Using single-molecule tracking, we report that loss of Gpsm2 leads to decreased outgrowth and a disruption of actin dynamics in neuronal growth cones. Our results elucidate the aetiology of CMCS and highlight a new molecular role for Gpsm2/Gαi3 in the regulation of actin dynamics in epithelial and neuronal tissues. Mutations in GPSM2 cause a rare disease characterized by deafness and brain abnormalities. Here the authors show that Gpsm2 forms a molecular complex with a heterotrimeric G-protein subunit, whirlin and a myosin motor to regulate actin dynamics in neurons and auditory hair cell stereocilia.
Collapse
|
33
|
Suthakar K, Ryugo DK. Descending projections from the inferior colliculus to medial olivocochlear efferents: Mice with normal hearing, early onset hearing loss, and congenital deafness. Hear Res 2017; 343:34-49. [DOI: 10.1016/j.heares.2016.06.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 06/20/2016] [Accepted: 06/24/2016] [Indexed: 11/24/2022]
|
34
|
Masters TA, Kendrick-Jones J, Buss F. Myosins: Domain Organisation, Motor Properties, Physiological Roles and Cellular Functions. Handb Exp Pharmacol 2017; 235:77-122. [PMID: 27757761 DOI: 10.1007/164_2016_29] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Myosins are cytoskeletal motor proteins that use energy derived from ATP hydrolysis to generate force and movement along actin filaments. Humans express 38 myosin genes belonging to 12 classes that participate in a diverse range of crucial activities, including muscle contraction, intracellular trafficking, cell division, motility, actin cytoskeletal organisation and cell signalling. Myosin malfunction has been implicated a variety of disorders including deafness, hypertrophic cardiomyopathy, Usher syndrome, Griscelli syndrome and cancer. In this chapter, we will first discuss the key structural and kinetic features that are conserved across the myosin family. Thereafter, we summarise for each member in turn its unique functional and structural adaptations, cellular roles and associated pathologies. Finally, we address the broad therapeutic potential for pharmacological interventions that target myosin family members.
Collapse
Affiliation(s)
- Thomas A Masters
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK.
| | | | - Folma Buss
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK
| |
Collapse
|
35
|
Weck ML, Grega-Larson NE, Tyska MJ. MyTH4-FERM myosins in the assembly and maintenance of actin-based protrusions. Curr Opin Cell Biol 2016; 44:68-78. [PMID: 27836411 DOI: 10.1016/j.ceb.2016.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 10/12/2016] [Indexed: 12/13/2022]
Abstract
Unconventional myosins are actin-based molecular motors that serve a multitude of roles within the cell. One group of myosin motors, the MyTH4-FERM myosins, play an integral part in building and maintaining finger-like protrusions, which allow cells to interact with their external environment. Suggested to act primarily as transporters, these motor proteins enrich adhesion molecules, actin-regulatory proteins and other factors at the tips of filopodia, microvilli, and stereocilia. Below we review data from biophysical, biochemical, and cell biological studies, which implicate these myosins as central players in the assembly, maintenance and function of actin-based protrusions.
Collapse
Affiliation(s)
- Meredith L Weck
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 3154 MRB III, PMB 407935, 465 21st Avenue South, Nashville, TN 37240-7935, United States
| | - Nathan E Grega-Larson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 3154 MRB III, PMB 407935, 465 21st Avenue South, Nashville, TN 37240-7935, United States
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 3154 MRB III, PMB 407935, 465 21st Avenue South, Nashville, TN 37240-7935, United States.
| |
Collapse
|
36
|
Naz S, Imtiaz A, Mujtaba G, Maqsood A, Bashir R, Bukhari I, Khan MR, Ramzan M, Fatima A, Rehman AU, Iqbal M, Chaudhry T, Lund M, Brewer CC, Morell RJ, Friedman TB. Genetic causes of moderate to severe hearing loss point to modifiers. Clin Genet 2016; 91:589-598. [PMID: 27573290 DOI: 10.1111/cge.12856] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/17/2016] [Accepted: 08/22/2016] [Indexed: 11/30/2022]
Abstract
The genetic underpinnings of recessively inherited moderate to severe sensorineural hearing loss are not well understood, despite its higher prevalence in comparison to profound deafness. We recruited 92 consanguineous families segregating stable or progressive, recessively inherited moderate or severe hearing loss. We utilized homozygosity mapping, Sanger sequencing, targeted capture of known deafness genes with massively parallel sequencing and whole exome sequencing to identify the molecular basis of hearing loss in these families. Variants of the known deafness genes were found in 69% of the participating families with the SLC26A4, GJB2, MYO15A, TMC1, TMPRSS3, OTOF, MYO7A and CLDN14 genes together accounting for hearing loss in 54% of the families. We identified 20 reported and 21 novel variants in 21 known deafness genes; 16 of the 20 reported variants, previously associated with stable, profound deafness were associated with moderate to severe or progressive hearing loss in our families. These data point to a prominent role for genetic background, environmental factors or both as modifiers of human hearing loss severity.
Collapse
Affiliation(s)
- Sadaf Naz
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Ayesha Imtiaz
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan.,Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| | - Ghulam Mujtaba
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Azra Maqsood
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Rasheeda Bashir
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Ihtisham Bukhari
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Muhammad R Khan
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Memoona Ramzan
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Amara Fatima
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Atteeq U Rehman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| | - Muddassar Iqbal
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Taimur Chaudhry
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| | - Merete Lund
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| | - Carmen C Brewer
- Audiology Unit, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| | - Robert J Morell
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892.,Genomics and Computational Biology Core, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA 20892
| |
Collapse
|
37
|
Rehman AU, Bird JE, Faridi R, Shahzad M, Shah S, Lee K, Khan SN, Imtiaz A, Ahmed ZM, Riazuddin S, Santos-Cortez RLP, Ahmad W, Leal SM, Riazuddin S, Friedman TB. Mutational Spectrum of MYO15A and the Molecular Mechanisms of DFNB3 Human Deafness. Hum Mutat 2016; 37:991-1003. [PMID: 27375115 DOI: 10.1002/humu.23042] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/26/2016] [Indexed: 12/17/2022]
Abstract
Deafness in humans is a common neurosensory disorder and is genetically heterogeneous. Across diverse ethnic groups, mutations of MYO15A at the DFNB3 locus appear to be the third or fourth most common cause of autosomal-recessive, nonsyndromic deafness. In 49 of the 67 exons of MYO15A, there are currently 192 recessive mutations identified, including 14 novel mutations reported here. These mutations are distributed uniformly across MYO15A with one enigmatic exception; the alternatively spliced giant exon 2, encoding 1,233 residues, has 17 truncating mutations but no convincing deafness-causing missense mutations. MYO15A encodes three distinct isoform classes, one of which is 395 kDa (3,530 residues), the largest member of the myosin superfamily of molecular motors. Studies of Myo15 mouse models that recapitulate DFNB3 revealed two different pathogenic mechanisms of hearing loss. In the inner ear, myosin 15 is necessary both for the development and the long-term maintenance of stereocilia, mechanosensory sound-transducing organelles that extend from the apical surface of hair cells. The goal of this Mutation Update is to provide a comprehensive review of mutations and functions of MYO15A.
Collapse
Affiliation(s)
- Atteeq U Rehman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, 20892
| | - Jonathan E Bird
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, 20892
| | - Rabia Faridi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, 20892.,Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, 54550, Pakistan
| | - Mohsin Shahzad
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, Maryland, 21201
| | - Sujay Shah
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, 20892
| | - Kwanghyuk Lee
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Shaheen N Khan
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, 54550, Pakistan
| | - Ayesha Imtiaz
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, 20892
| | - Zubair M Ahmed
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, Maryland, 21201
| | - Saima Riazuddin
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, Maryland, 21201
| | - Regie Lyn P Santos-Cortez
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Wasim Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Suzanne M Leal
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Sheikh Riazuddin
- Allama Iqbal Medical Research Centre, Jinnah Hospital Complex, University of Health Sciences, Lahore, 54550, Pakistan
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, 20892.
| |
Collapse
|
38
|
Connelly CJ, Ryugo DK, Muniak MA. The effect of progressive hearing loss on the morphology of endbulbs of Held and bushy cells. Hear Res 2016; 343:14-33. [PMID: 27473502 DOI: 10.1016/j.heares.2016.07.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 10/21/2022]
Abstract
Studies of congenital and early-onset deafness have demonstrated that an absence of peripheral sound-evoked activity in the auditory nerve causes pathological changes in central auditory structures. The aim of this study was to establish whether progressive acquired hearing loss could lead to similar brain changes that would degrade the precision of signal transmission. We used complementary physiologic hearing tests and microscopic techniques to study the combined effect of both magnitude and duration of hearing loss on one of the first auditory synapses in the brain, the endbulb of Held (EB), along with its bushy cell (BC) target in the anteroventral cochlear nucleus. We compared two hearing mouse strains (CBA/Ca and heterozygous shaker-2+/-) against a model of early-onset progressive hearing loss (DBA/2) and a model of congenital deafness (homozygous shaker-2-/-), examining each strain at 1, 3, and 6 months of age. Furthermore, we employed a frequency model of the mouse cochlear nucleus to constrain our analyses to regions most likely to exhibit graded changes in hearing function with time. No significant differences in the gross morphology of EB or BC structure were observed in 1-month-old animals, indicating uninterrupted development. However, in animals with hearing loss, both EBs and BCs exhibited a graded reduction in size that paralleled the hearing loss, with the most severe pathology seen in deaf 6-month-old shaker-2-/- mice. Ultrastructural pathologies associated with hearing loss were less dramatic: minor changes were observed in terminal size but mitochondrial fraction and postsynaptic densities remained relatively stable. These results indicate that acquired progressive hearing loss can have consequences on auditory brain structure, with prolonged loss leading to greater pathologies. Our findings suggest a role for early intervention with assistive devices in order to mitigate long-term pathology and loss of function.
Collapse
Affiliation(s)
- Catherine J Connelly
- Hearing Research Unit, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia; School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW 2052, Australia.
| | - David K Ryugo
- Hearing Research Unit, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia; School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW 2052, Australia; Department of Otolaryngology, Head, Neck & Skull Base Surgery, St Vincent's Hospital, Sydney, NSW 2010, Australia
| | - Michael A Muniak
- Hearing Research Unit, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
| |
Collapse
|
39
|
Egilmez OK, Kalcioglu MT. Genetics of Nonsyndromic Congenital Hearing Loss. SCIENTIFICA 2016; 2016:7576064. [PMID: 26989561 PMCID: PMC4775805 DOI: 10.1155/2016/7576064] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 01/19/2016] [Indexed: 06/05/2023]
Abstract
Congenital hearing impairment affects nearly 1 in every 1000 live births and is the most frequent birth defect in developed societies. Hereditary types of hearing loss account for more than 50% of all congenital sensorineural hearing loss cases and are caused by genetic mutations. HL can be either nonsyndromic, which is restricted to the inner ear, or syndromic, a part of multiple anomalies affecting the body. Nonsyndromic HL can be categorised by mode of inheritance, such as autosomal dominant (called DFNA), autosomal recessive (DFNB), mitochondrial, and X-linked (DFN). To date, 125 deafness loci have been reported in the literature: 58 DFNA loci, 63 DFNB loci, and 4 X-linked loci. Mutations in genes that control the adhesion of hair cells, intracellular transport, neurotransmitter release, ionic hemeostasis, and cytoskeleton of hair cells can lead to malfunctions of the cochlea and inner ear. In recent years, with the increase in studies about genes involved in congenital hearing loss, genetic counselling and treatment options have emerged and increased in availability. This paper presents an overview of the currently known genes associated with nonsyndromic congenital hearing loss and mutations in the inner ear.
Collapse
Affiliation(s)
- Oguz Kadir Egilmez
- Department of Otorhinolaryngology, Faculty of Medicine, Istanbul Medeniyet University, 34722 Istanbul, Turkey
| | - M. Tayyar Kalcioglu
- Department of Otorhinolaryngology, Faculty of Medicine, Istanbul Medeniyet University, 34722 Istanbul, Turkey
| |
Collapse
|
40
|
Li W, Guo L, Li Y, Wu Q, Li Q, Li H, Dai C. A novel recessive truncating mutation in MYO15A causing prelingual sensorineural hearing loss. Int J Pediatr Otorhinolaryngol 2016; 81:92-5. [PMID: 26810297 DOI: 10.1016/j.ijporl.2015.12.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 12/18/2015] [Accepted: 12/19/2015] [Indexed: 12/11/2022]
Abstract
Hearing loss (HL) is one of the most common human defects which affects millions of people globally. The identification of deafness-related genes or loci may facilitate basic and clinical translational research on this disorder. Here, we investigated a Chinese family with autosomal recessive non-syndromic hearing impairment. Using targeted massively parallel sequencing, we identified a novel homozygous mutation, c.3525_3526insA and p.Q1175fsX1188 (NM_016239), in exon 2 of MYO15A. Sanger sequencing confirmed that affected siblings were homozygous for the mutation, whereas both normal hearing parents were heterozygous. The mutation was absent in 96 healthy controls and public databases. The insertion leads to a frameshift and a truncated form of the protein, resulting in the pathogenic effect of hearing loss for the patients. Mutations in exon 2 of MYO15A may cause a less severe phenotype, facilitating the rapid identification of mutations in exon 2 among the 66 exons when linkage of less severe hearing loss to Deafness, Autosomal Recessive 3 (DFNB3) is detected. Our data provide additional molecular information for establishing a better genotype-phenotype understanding of DFNB3.
Collapse
Affiliation(s)
- Wei Li
- Department of Otorhinolaryngology, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China; Hearing Medicine Key Laboratory of Ministry of Health, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China
| | - Luo Guo
- Research Center, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China
| | - Yu Li
- Department of Otorhinolaryngology, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China; Hearing Medicine Key Laboratory of Ministry of Health, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China
| | - Qianru Wu
- Department of Otorhinolaryngology, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China; Hearing Medicine Key Laboratory of Ministry of Health, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China
| | - Qingzhong Li
- Department of Otorhinolaryngology, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China; Hearing Medicine Key Laboratory of Ministry of Health, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China
| | - Huawei Li
- Department of Otorhinolaryngology, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China; Hearing Medicine Key Laboratory of Ministry of Health, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China
| | - Chunfu Dai
- Department of Otorhinolaryngology, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China; Hearing Medicine Key Laboratory of Ministry of Health, Eye Ear Nose & Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, China.
| |
Collapse
|
41
|
Faber-Hammond J, Samanta MP, Whitchurch EA, Manning D, Sisneros JA, Coffin AB. Saccular Transcriptome Profiles of the Seasonal Breeding Plainfin Midshipman Fish (Porichthys notatus), a Teleost with Divergent Sexual Phenotypes. PLoS One 2015; 10:e0142814. [PMID: 26560106 PMCID: PMC4641692 DOI: 10.1371/journal.pone.0142814] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 10/27/2015] [Indexed: 11/18/2022] Open
Abstract
Acoustic communication is essential for the reproductive success of the plainfin midshipman fish (Porichthys notatus). During the breeding season, type I males use acoustic cues to advertise nest location to potential mates, creating an audible signal that attracts reproductive females. Type II (sneaker) males also likely use this social acoustic signal to find breeding pairs from which to steal fertilizations. Estrogen-induced changes in the auditory system of breeding females are thought to enhance neural encoding of the advertisement call, and recent anatomical data suggest the saccule (the main auditory end organ) as one possible target for this seasonal modulation. Here we describe saccular transcriptomes from all three sexual phenotypes (females, type I and II males) collected during the breeding season as a first step in understanding the mechanisms underlying sexual phenotype-specific and seasonal differences in auditory function. We used RNA-Seq on the Ion Torrent platform to create a combined transcriptome dataset containing over 79,000 assembled transcripts representing almost 9,000 unique annotated genes. These identified genes include several with known inner ear function and multiple steroid hormone receptors. Transcripts most closely matched to published genomes of nile tilapia and large yellow croaker, inconsistent with the phylogenetic relationship between these species but consistent with the importance of acoustic communication in their life-history strategies. We then compared the RNA-Seq results from the saccules of reproductive females with a separate transcriptome from the non-reproductive female phenotype and found over 700 differentially expressed transcripts, including members of the Wnt and Notch signaling pathways that mediate cell proliferation and hair cell addition in the inner ear. These data constitute a valuable resource for furthering our understanding of the molecular basis for peripheral auditory function as well as a range of future midshipman and cross-species comparative studies of the auditory periphery.
Collapse
Affiliation(s)
- Joshua Faber-Hammond
- College of Arts and Sciences, Washington State University, Vancouver, WA, United States of America
| | | | - Elizabeth A. Whitchurch
- Department of Biological Sciences, Humboldt State University, Arcata, CA, United States of America
| | - Dustin Manning
- College of Arts and Sciences, Washington State University, Vancouver, WA, United States of America
| | - Joseph A. Sisneros
- Department of Psychology, University of Washington, Seattle, WA, United States of America
| | - Allison B. Coffin
- College of Arts and Sciences, Washington State University, Vancouver, WA, United States of America
- Department of Integrative Physiology and Neuroscience, Washington State University, Vancouver, WA, United States of America
- * E-mail:
| |
Collapse
|
42
|
Nicolson T. It takes two. eLife 2015; 4. [PMID: 26439013 PMCID: PMC4592937 DOI: 10.7554/elife.11399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Two forms of an unconventional myosin motor protein have separate functions in the growth and maintenance of hair bundles in auditory hair cells.
Collapse
Affiliation(s)
- Teresa Nicolson
- Oregon Hearing Research Center and the Vollum Institute, Oregon Health and Science University, Portland, United States
| |
Collapse
|
43
|
Chang MY, Kim AR, Kim NK, Lee C, Lee KY, Jeon WS, Koo JW, Oh SH, Park WY, Kim D, Choi BY. Identification and Clinical Implications of Novel MYO15A Mutations in a Non-consanguineous Korean Family by Targeted Exome Sequencing. Mol Cells 2015; 38:781-8. [PMID: 26242193 PMCID: PMC4588721 DOI: 10.14348/molcells.2015.0078] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/11/2015] [Indexed: 12/02/2022] Open
Abstract
Mutations of MYO15A are generally known to cause severe to profound hearing loss throughout all frequencies. Here, we found two novel MYO15A mutations, c.3871C>T (p.L1291F) and c.5835T>G (p.Y1945X) in an affected individual carrying congenital profound sensorineural hearing loss (SNHL) through targeted resequencing of 134 known deafness genes. The variant, p.L1291F and p.Y1945X, resided in the myosin motor and IQ2 domains, respectively. The p.L1291F variant was predicted to affect the structure of the actin-binding site from three-dimensional protein modeling, thereby interfering with the correct interaction between actin and myosin. From the literature analysis, mutations in the N-terminal domain were more frequently associated with residual hearing at low frequencies than mutations in the other regions of this gene. Therefore we suggest a hypothetical genotype-phenotype correlation whereby MYO15A mutations that affect domains other than the N-terminal domain, lead to profound SNHL throughout all frequencies and mutations that affect the N-terminal domain, result in residual hearing at low frequencies. This genotype-phenotype correlation suggests that preservation of residual hearing during auditory rehabilitation like cochlear implantation should be intended for those who carry mutations in the N-terminal domain and that individuals with mutations elsewhere in MYO15A require early cochlear implantation to timely initiate speech development.
Collapse
Affiliation(s)
- Mun Young Chang
- Department of Otorhinolaryngology, Seoul National University Hospital, Seoul national University College of Medicine, Seoul 110-744,
Korea
| | - Ah Reum Kim
- Department of Otorhinolaryngology, Seoul National University Hospital, Seoul national University College of Medicine, Seoul 110-744,
Korea
| | - Nayoung K.D. Kim
- Samsung Genome Institute, Samsung Medical Center, Seoul 135-710,
Korea
| | - Chung Lee
- Samsung Genome Institute, Samsung Medical Center, Seoul 135-710,
Korea
- Samsung Advanced Institute for Health Sciences and Technology, Seoul 135-710,
Korea
| | - Kyoung Yeul Lee
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701,
Korea
| | - Woo-Sung Jeon
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701,
Korea
| | - Ja-Won Koo
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, Seongnam 463-707,
Korea
| | - Seung Ha Oh
- Department of Otorhinolaryngology, Seoul National University Hospital, Seoul national University College of Medicine, Seoul 110-744,
Korea
| | - Woong-Yang Park
- Samsung Genome Institute, Samsung Medical Center, Seoul 135-710,
Korea
- Samsung Advanced Institute for Health Sciences and Technology, Seoul 135-710,
Korea
- Department of Molecular Cell Biology, School of Medicine, Sungkyunkwan University, Suwon 440-746,
Korea
| | - Dongsup Kim
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701,
Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, Seongnam 463-707,
Korea
| |
Collapse
|
44
|
Xia H, Huang X, Guo Y, Hu P, He G, Deng X, Xu H, Yang Z, Deng H. Identification of a Novel MYO15A Mutation in a Chinese Family with Autosomal Recessive Nonsyndromic Hearing Loss. PLoS One 2015; 10:e0136306. [PMID: 26308726 PMCID: PMC4550393 DOI: 10.1371/journal.pone.0136306] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 08/02/2015] [Indexed: 01/08/2023] Open
Abstract
Autosomal recessive nonsyndromic hearing loss (ARNSHL) is a genetically heterogeneous sensorineural disorder, generally manifested with prelingual hearing loss and absence of other clinical manifestations. The aim of this study is to identify the pathogenic gene in a four-generation consanguineous Chinese family with ARNSHL. A novel homozygous variant, c.9316dupC (p.H3106Pfs*2), in the myoxin XVa gene (MYO15A) was identified by exome sequencing and Sanger sequencing. The homozygous MYO15A c.9316dupC variant co-segregated with the phenotypes in the ARNSHL family and was absent in two hundred normal controls. The variant was predicted to interfere with the formation of the Myosin XVa-whirlin-Eps8 complex at the tip of stereocilia, which is indispensable for stereocilia elongation. Our data suggest that the homozygous MYO15A c.9316dupC variant might be the pathogenic mutation, and exome sequencing is a powerful molecular diagnostic strategy for ARNSHL, an extremely heterogeneous disorder. Our findings extend the mutation spectrum of the MYO15A gene and have important implications for genetic counseling for the family.
Collapse
Affiliation(s)
- Hong Xia
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
- Department of Emergency, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Xiangjun Huang
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Yi Guo
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
- Department of Medical Information, Xiangya School of Medicine, Central South University, Changsha, China
| | - Pengzhi Hu
- Department of Radiology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Guangxiang He
- Department of Otolaryngology-Head Neck Surgery, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Xiong Deng
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Hongbo Xu
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Zhijian Yang
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Hao Deng
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
- * E-mail:
| |
Collapse
|
45
|
Fang Q, Indzhykulian AA, Mustapha M, Riordan GP, Dolan DF, Friedman TB, Belyantseva IA, Frolenkov GI, Camper SA, Bird JE. The 133-kDa N-terminal domain enables myosin 15 to maintain mechanotransducing stereocilia and is essential for hearing. eLife 2015; 4. [PMID: 26302205 PMCID: PMC4592939 DOI: 10.7554/elife.08627] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 08/22/2015] [Indexed: 11/13/2022] Open
Abstract
The precise assembly of inner ear hair cell stereocilia into rows of increasing height is critical for mechanotransduction and the sense of hearing. Yet, how the lengths of actin-based stereocilia are regulated remains poorly understood. Mutations of the molecular motor myosin 15 stunt stereocilia growth and cause deafness. We found that hair cells express two isoforms of myosin 15 that differ by inclusion of an 133-kDa N-terminal domain, and that these isoforms can selectively traffic to different stereocilia rows. Using an isoform-specific knockout mouse, we show that hair cells expressing only the small isoform remarkably develop normal stereocilia bundles. However, a critical subset of stereocilia with active mechanotransducer channels subsequently retracts. The larger isoform with the 133-kDa N-terminal domain traffics to these specialized stereocilia and prevents disassembly of their actin core. Our results show that myosin 15 isoforms can navigate between functionally distinct classes of stereocilia, and are independently required to assemble and then maintain the intricate hair bundle architecture.
Collapse
Affiliation(s)
- Qing Fang
- Department of Human Genetics, University of Michigan, Ann Arbor, United States
| | | | - Mirna Mustapha
- Department of Human Genetics, University of Michigan, Ann Arbor, United States
| | - Gavin P Riordan
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, United States
| | - David F Dolan
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, United States
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, United States
| | - Inna A Belyantseva
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, United States
| | | | - Sally A Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, United States
| | - Jonathan E Bird
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, United States
| |
Collapse
|
46
|
Chaperone-enhanced purification of unconventional myosin 15, a molecular motor specialized for stereocilia protein trafficking. Proc Natl Acad Sci U S A 2014; 111:12390-5. [PMID: 25114250 DOI: 10.1073/pnas.1409459111] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Unconventional myosin 15 is a molecular motor expressed in inner ear hair cells that transports protein cargos within developing mechanosensory stereocilia. Mutations of myosin 15 cause profound hearing loss in humans and mice; however, the properties of this motor and its regulation within the stereocilia organelle are unknown. To address these questions, we expressed a subfragment 1-like (S1) truncation of mouse myosin 15, comprising the predicted motor domain plus three light-chain binding sites. Following unsuccessful attempts to express functional myosin 15-S1 using the Spodoptera frugiperda (Sf9)-baculovirus system, we discovered that coexpression of the muscle-myosin-specific chaperone UNC45B, in addition to the chaperone heat-shock protein 90 (HSP90) significantly increased the yield of functional protein. Surprisingly, myosin 15-S1 did not bind calmodulin with high affinity. Instead, the IQ domains bound essential and regulatory light chains that are normally associated with class II myosins. We show that myosin 15-S1 is a barbed-end-directed motor that moves actin filaments in a gliding assay (∼ 430 nm · s(-1) at 30 °C), using a power stroke of 7.9 nm. The maximum ATPase rate (k(cat) ∼ 6 s(-1)) was similar to the actin-detachment rate (k(det) = 6.2 s(-1)) determined in single molecule optical trapping experiments, indicating that myosin 15-S1 was rate limited by transit through strongly actin-bound states, similar to other processive myosin motors. Our data further indicate that in addition to folding muscle myosin, UNC45B facilitates maturation of an unconventional myosin. We speculate that chaperone coexpression may be a simple method to optimize the purification of other myosin motors from Sf9 insect cells.
Collapse
|
47
|
Woo HM, Park HJ, Baek JI, Park MH, Kim UK, Sagong B, Koo SK. Whole-exome sequencing identifies MYO15A mutations as a cause of autosomal recessive nonsyndromic hearing loss in Korean families. BMC MEDICAL GENETICS 2013; 14:72. [PMID: 23865914 PMCID: PMC3727941 DOI: 10.1186/1471-2350-14-72] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 07/09/2013] [Indexed: 01/05/2023]
Abstract
Background The genetic heterogeneity of hearing loss makes genetic diagnosis expensive and time consuming using available methods. Whole-exome sequencing has recently been introduced as an alternative approach to identifying causative mutations in Mendelian disorders. Methods To identify the hidden mutations that cause autosomal recessive nonsyndromic hearing loss (ARNSHL), we performed whole-exome sequencing of 13 unrelated Korean small families with ARNSHL who were negative for GJB2 or SLC26A4 mutations. Results We found two novel compound heterozygous mutations, IVS11 + 1 and p.R2146Q, of MYO15A in one (SR903 family) of the 13 families with ARNSHL. In addition to these causative mutations, 13 nonsynonymous variants, including variants with uncertain pathogenicity (SR285 family), were identified in the coding exons of MYO15A from Korean exomes. Conclusion This is the first report of MYO15A mutations in an East Asian population. We suggest that close attention should be paid to this gene when performing genetic testing of patients with hearing loss in East Asia. The present results also indicate that whole-exome sequencing is a valuable method for comprehensive medical diagnosis of a genetically heterogeneous recessive disease, especially in small-sized families.
Collapse
Affiliation(s)
- Hae-Mi Woo
- Division of Intractable Diseases, Center for Biomedical Sciences, National Institute of Health, Chungcheongbuk-do 363-951, South Korea
| | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
Cytoskeletal trafficking systems are becoming more complex at every turn. A new study reports that a yeast myosin V walks on only a select few actin filaments - those that are decorated with tropomyosin.
Collapse
|
49
|
Roeseler DA, Sachdev S, Buckley DM, Joshi T, Wu DK, Xu D, Hannink M, Waters ST. Elongation factor 1 alpha1 and genes associated with Usher syndromes are downstream targets of GBX2. PLoS One 2012; 7:e47366. [PMID: 23144817 PMCID: PMC3493575 DOI: 10.1371/journal.pone.0047366] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 09/12/2012] [Indexed: 11/18/2022] Open
Abstract
Gbx2 encodes a DNA-binding transcription factor that plays pivotal roles during embryogenesis. Gain-and loss-of-function studies in several vertebrate species have demonstrated a requirement for Gbx2 in development of the anterior hindbrain, spinal cord, inner ear, heart, and neural crest cells. However, the target genes through which GBX2 exerts its effects remain obscure. Using chromatin immunoprecipitation coupled with direct sequencing (ChIP-Seq) analysis in a human prostate cancer cell line, we identified cis-regulatory elements bound by GBX2 to provide insight into its direct downstream targets. The analysis revealed more than 286 highly significant candidate target genes, falling into various functional groups, of which 51% are expressed in the nervous system. Several of the top candidate genes include EEF1A1, ROBO1, PLXNA4, SLIT3, NRP1, and NOTCH2, as well as genes associated with the Usher syndrome, PCDH15 and USH2A, and are plausible candidates contributing to the developmental defects in Gbx2(-/-) mice. We show through gel shift analyses that sequences within the promoter or introns of EEF1A1, ROBO1, PCDH15, USH2A and NOTCH2, are directly bound by GBX2. Consistent with these in vitro results, analyses of Gbx2(-/-) embryos indicate that Gbx2 function is required for migration of Robo1-expressing neural crest cells out of the hindbrain. Furthermore, we show that GBX2 activates transcriptional activity through the promoter of EEF1A1, suggesting that GBX2 could also regulate gene expression indirectly via EEF1A. Taken together, our studies show that GBX2 plays a dynamic role in development and diseases.
Collapse
Affiliation(s)
- David A. Roeseler
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, United States of America
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
| | - Shrikesh Sachdev
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Biochemistry, University of Missouri, Columbia, Missouri, United States of America
| | - Desire M. Buckley
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, United States of America
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
| | - Trupti Joshi
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Computer Science, University of Missouri, Columbia, Missouri, United States of America
- Informatics Institute, University of Missouri, Columbia, Missouri, United States of America
| | - Doris K. Wu
- Laboratory of Molecular Biology, NIDCD, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Dong Xu
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Computer Science, University of Missouri, Columbia, Missouri, United States of America
- Informatics Institute, University of Missouri, Columbia, Missouri, United States of America
| | - Mark Hannink
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Biochemistry, University of Missouri, Columbia, Missouri, United States of America
| | - Samuel T. Waters
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, United States of America
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
| |
Collapse
|
50
|
Abstract
The development of cell-cell junctions was a fundamental step in metazoan evolution, and human health depends on the formation and function of cell junctions. Although it has long been known that actin and conventional myosin have important roles in cell junctions, research has begun to reveal the specific functions of the different forms of conventional myosin. Exciting new data also reveals that a growing number of unconventional myosins have important roles in cell junctions. Experiments showing that cell junctions act as mechanosensors have also provided new impetus to understand the functions of myosins and the forces they exert. In this review we will summarize recent developments on the roles of myosins in cell junctions.
Collapse
Affiliation(s)
- Katy C Liu
- Department of Cell and Molecular Physiology; School of Medicine; University of North Carolina at Chapel Hill; Chapel Hill, NC USA
| | - Richard E Cheney
- Department of Cell and Molecular Physiology; School of Medicine; University of North Carolina at Chapel Hill; Chapel Hill, NC USA
| |
Collapse
|