DOCSLIB.ORG

Tip-Link Protein Protocadherin 15 Interacts with Transmembrane Channel-Like Proteins TMC1 and TMC2

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Tip-Link Protein Protocadherin 15 Interacts with Transmembrane Channel-Like Proteins TMC1 and TMC2 Tip-link protein protocadherin 15 interacts with transmembrane channel-like proteins TMC1 and TMC2 Reo Maedaa,b,1, Katie S. Kindta,b,1,2, Weike Moa,b,1, Clive P. Morgana,b, Timothy Ericksona,b, Hongyu Zhaoa,b, Rachel Clemens-Grishama,b, Peter G. Barr-Gillespiea,b, and Teresa Nicolsona,b,3 aOregon Hearing Research Center and bVollum Institute, Oregon Health and Science University, Portland, OR 97239 Edited by A. J. Hudspeth, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, and approved July 23, 2014 (received for review February 3, 2014) The tip link protein protocadherin 15 (PCDH15) is a central compo- vestibular deficits, along with the complete absence of normal nent of the mechanotransduction complex in auditory and vestib- mechanotransduction currents in auditory and vestibular hair cells ular hair cells. PCDH15 is hypothesized to relay external forces to the (17). Changes in calcium permeability through the transduction mechanically gated channel located near its cytoplasmic C terminus. channel of cochlear hair cells were observed for Tmc1 Tmc2 How PCDH15 is coupled to the transduction machinery is not clear. double-mutant mice, as well as in single mutants of either gene Using a membrane-based two-hybrid screen to identify proteins (10, 18, 19). In further support of the idea that TMCs are pore- that bind to PCDH15, we detected an interaction between zebrafish forming subunits of the transduction channel, mouse vestibular Pcdh15a and an N-terminal fragment of transmembrane channel- hair cells that express only the dominant Beethoven (M412K) al- like 2a (Tmc2a). Tmc2a is an ortholog of mammalian TMC2, which lele of Tmc1, in the absence of any wild-type TMC1 or TMC2, along with TMC1 has been implicated in mechanotransduction in display altered single-channel transduction currents (10). Curi- mammalian hair cells. Using the above-mentioned two-hybrid assay, ously, an 180° phase-shifted transduction current can be evoked in we found that zebrafish Tmc1 and Tmc2a can interact with the CD1 cochlear hair cells expressing only the deafness allele of Tmc1 − − or CD3 cytoplasmic domain isoforms of Pcdh15a, and this interaction (Tmc1dn/dn Tmc2 / ) (19). The source of this anomalous current is depends on the common region shared between the two Pcdh15 not clear, but a similar current is also observed in hair cells where isoforms. Moreover, an interaction between mouse PCDH15-CD3 tip links have been disrupted by either genetic lesions (Pcdh15av3J, and TMC1 or TMC2 was observed in both yeast two-hybrid assays Cdh23v2J) or by 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tet- and coimmunoprecipitation experiments. To determine whether the raacetic acid (BAPTA) treatment (7, 19, 20). Although the − − Pcdh15–Tmc interaction is relevant to mechanotransduction in vivo, anomalous current seen in Tmc1dn/dn Tmc2 / hair cells calls into we overexpressed N-terminal fragments of Tmc2a in zebrafish hair question whether TMC1 and TMC2 serve as pore-forming sub- cells. Overexpression of the Tmc2a N terminus results in mislocaliza- units of the mechanotransduction complex, it is nonetheless clear tion of Pcdh15a within hair bundles, together with a significant de- that these proteins are essential for normal transduction and crease in mechanosensitive responses, suggesting that a Pcdh15a– modulate the channel’s properties. However, how the TMCs in- Tmc complex is critical for mechanotransduction. Together, these teract with other components of the mechanotransduction com- results identify an evolutionarily conserved association between plex has not yet been investigated. the fish and mouse orthologs of PCDH15 and TMC1 and TMC2, sup- Given that PCDH15 may be located at the site of mechano- porting the notion that TMCs are key components of the transduc- transduction, we performed a split-ubiquitin yeast two-hybrid tion complex in hair cells. screen with zebrafish Pcdh15a to identify proteins that could serve as subunits of the mechanotransduction complex. Our ensory hair cells are specialized mechanosensory cells that unbiased screen identified an interaction with the N terminus of Srespond to auditory and vestibular stimuli with their apical zebrafish Tmc2a, an ortholog of mammalian TMC2. Both Tmc1 hair bundles. Each bundle consists of rows of stereocilia that are and Tmc2a from zebrafish interact with the CD1 and/or CD3 interconnected by extracellular tip links. Collective evidence suggests that tip link filaments are composed of protocadherin Significance 15 (PCDH15) and cadherin 23 (CDH23) (1), which are each encoded by deafness genes identified in humans, mice, and fish Our understanding of the molecular basis of our sense of hearing (1–5). Tip links are required for proper gating of mechano- and balance has improved significantly, although some of the transduction channels (1, 6, 7), and calcium imaging of trans- key players in sensory hair cells have yet to be identified. Sensory duction in rodent auditory hair cells indicates that transduction hair cells depend on extracellular filaments known as tip links to channels are associated with the lower end of tip links (8), where transduce mechanical stimuli into electrical signals. We demon- PCDH15 localizes (6, 9). Thus, integral membrane proteins that strate that the tip link protein PCDH15 interacts with two integral interact with PCDH15 are likely to be critical for mechano- member proteins, TMC1 and TMC2, which have recently been put transduction and may constitute subunits or accessory proteins forth as candidates for the mechanotransduction channel. of the transduction channel. To date, neither the identity of the transduction channel nor the mechanism of interaction between Author contributions: R.M., K.S.K., W.M., C.P.M., T.E., P.G.B.-G., and T.N. designed re- search; R.M., K.S.K., W.M., C.P.M., T.E., and R.C.-G. performed research; H.Z. contributed the tip link and the channel are known. new reagents/analytic tools; R.M., K.S.K., W.M., C.P.M., T.E., P.G.B.-G., and T.N. analyzed Recently, TMC1 and TMC2 were put forth as candidates for data; and K.S.K., T.E., P.G.B.-G., and T.N. wrote the paper. NEUROSCIENCE the pore-forming subunits of the mechanotransduction channel The authors declare no conflict of interest. in sensory hair cells (10). Each protein is predicted to have mul- This article is a PNAS Direct Submission. tiple membrane-spanning domains reminiscent of an ion channel 1R.M., K.S.K., and W.M. contributed equally to this work. structure (11, 12); in addition, the Caenorhabditis elegans family 2Present address: Section on Sensory Cell Development and Function, National Institute member TMC-1 has been shown to be a putative channel suffi- on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, cient for detection of high salt (13). Mammalian TMC1 has been MD 20892. implicated in both recessive and dominant forms of nonsyndromic 3To whom correspondence should be addressed. Email: [email protected]. – hearing loss in humans and mice (14 16). Moreover, double This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. knockout of mouse Tmc1 and Tmc2 results in severe auditory and 1073/pnas.1402152111/-/DCSupplemental. www.pnas.org/cgi/doi/10.1073/pnas.1402152111 PNAS | September 2, 2014 | vol. 111 | no. 35 | 12907–12912 Downloaded by guest on September 26, 2021 isoforms of Pcdh15a, and these interactions require the common region present in both cytoplasmic domains. Likewise, using two different methods of yeast two-hybrid assays and immunopre- cipitation experiments in a heterologous expression system, we show that mouse PCDH15-CD3 can interact with either TMC1 or TMC2. Finally, we overexpressed an N-terminal fragment of Tmc2a to disrupt the Tmc–Pcdh15 interaction in zebrafish hair cells and found a reduction in mechanically evoked calcium tran- sients. Thus, our work shows that a Tmc–Pcdh15 interaction is critical for hair cell mechanosensitivity. Results Membrane-Based Screen for Components of the Mechanotransduction Complex. To identify members of the mechanotransduction com- plex in hair cells, we performed a molecular screen for proteins that bind to the cytoplasmic tail of Pcdh15a. We took advantage of the split-ubiquitin two-hybrid screening method, which is spe- cifically designed to detect membrane protein interactions at the cytoplasmic face of the endoplasmic reticulum of yeast cells (21). This method is ideal for bait proteins that contain single or multiple transmembrane domains, such as cadherins. To generate the bait vectors, we first identified splice variants of pcdh15a in 5-d-old wild-type larvae by using RACE PCR to amplify the 3′ end of pcdh15a. In mice and humans, three major isoforms of PCDH15 have been reported: CD1, CD2, and CD3 (22, 23). As reported in previously (5), we detected the CD1 isoform in zebrafish, along with amplicons corresponding to a CD3 isoform (Fig. S1). We were unable to detect any products corresponding to a CD2 isoform. As in other vertebrates, a common region Fig. 1. Interaction of zebrafish Pcdh15a with Tmc2a and Tmc1 using a split- ubiquitin yeast two-hybrid assay. (A) The N terminus of zebrafish Tmc2a adjacent to the transmembrane domain is shared by both CD1 – and CD3 isoforms of Pcdh15a (Fig. S1). (1 117 aa) can interact with either CD1 or CD3 isoforms of Pcdh15a, and binding is dependent upon the common region (CR). Transfection efficiency For the bait vectors, we used truncated versions of Pcdh15a- is shown on SD-LeuTrp medium (Left). Protein–protein interactions were CD1 or Pcdh15a-CD3 containing the transmembrane domain detected on SD-LeuTrpHisAde selective media (Right). Shown from left to and the full cytoplasmic domain (Fig. S1). Prey vectors contained right on each plate is a fivefold serial dilution series of yeast cells. The Ost1- cDNA generated from the total RNA of ∼1,500 zebrafish larval NubI ubiquitin moiety was used as a positive control, and empty prey vector ears at 5 d postfertilization (dpf).
Load more

Recommended publications
  • Putative Pore-Forming Subunits of the Mechano-Electrical Transduction Channel
    bioRxiv preprint doi: https://doi.org/10.1101/393330; this version posted August 23, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 1 2 3 4 Putative pore-forming subunits of the mechano-electrical transduction channel, 5 Tmc1/2b, require Tmie to localize to the site of mechanotransduction in zebrafish 6 sensory hair cells 7 8 9 Itallia V. Pacentine and Teresa Nicolson* 10 Oregon Hearing Research Center and Vollum Institute, Oregon Health & Science University, 11 Portland, Oregon, United States of America 12 13 14 *Corresponding author 15 E-mail: [email protected] 1 bioRxiv preprint doi: https://doi.org/10.1101/393330; this version posted August 23, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 16 Abstract 17 Mutations in transmembrane inner ear (TMIE) cause deafness in humans; previous 18 studies suggest involvement in the mechano-electrical transduction (MET) complex in sensory 19 hair cells, but TMIE’s precise role is unclear. In tmie zebrafish mutants, we observed that GFP- 20 tagged Tmc1 and Tmc2b, which are putative subunits of the MET channel, fail to target to the 21 hair bundle. In contrast, overexpression of Tmie strongly enhances the targeting of Tmc2b-GFP 22 to stereocilia.
    [Show full text]
  • The Lhfpl5 Ohnologs Lhfpl5a and Lhfpl5b Are Required for Mechanotransduction in Distinct Populations of Sensory Hair Cells in Zebrafish
    fnmol-12-00320 January 2, 2020 Time: 14:35 # 1 ORIGINAL RESEARCH published: 15 January 2020 doi: 10.3389/fnmol.2019.00320 The lhfpl5 Ohnologs lhfpl5a and lhfpl5b Are Required for Mechanotransduction in Distinct Populations of Sensory Hair Cells in Zebrafish Timothy Erickson1,2*, Itallia V. Pacentine2, Alexandra Venuto1, Rachel Clemens2 and Teresa Nicolson2† 1 Department of Biology, East Carolina University, Greenville, NC, United States, 2 Oregon Hearing Research Center and Vollum Institute, Oregon Health and Science University, Portland, OR, United States Hair cells sense and transmit auditory, vestibular, and hydrodynamic information by converting mechanical stimuli into electrical signals. This process of mechano-electrical transduction (MET) requires a mechanically gated channel localized in the apical Edited by: stereocilia of hair cells. In mice, lipoma HMGIC fusion partner-like 5 (LHFPL5) acts Isabel Varela-Nieto, as an auxiliary subunit of the MET channel whose primary role is to correctly localize Spanish National Research Council (CSIC), Spain PCDH15 and TMC1 to the mechanotransduction complex. Zebrafish have two lhfpl5 Reviewed by: genes (lhfpl5a and lhfpl5b), but their individual contributions to MET channel assembly Hiroshi Hibino, and function have not been analyzed. Here we show that the zebrafish lhfpl5 genes Niigata University, Japan are expressed in discrete populations of hair cells: lhfpl5a expression is restricted to Sangyong Jung, Singapore Bioimaging Consortium auditory and vestibular hair cells in the inner ear, while lhfpl5b expression is specific ∗ (A STAR), Singapore to hair cells of the lateral line organ. Consequently, lhfpl5a mutants exhibit defects in Gwenaelle Geleoc, Harvard Medical School, auditory and vestibular function, while disruption of lhfpl5b affects hair cells only in the United States lateral line neuromasts.
    [Show full text]
  • A Clinicopathological and Molecular Genetic Analysis of Low-Grade Glioma in Adults
    A CLINICOPATHOLOGICAL AND MOLECULAR GENETIC ANALYSIS OF LOW-GRADE GLIOMA IN ADULTS Presented by ANUSHREE SINGH MSc A thesis submitted in partial fulfilment of the requirements of the University of Wolverhampton for the degree of Doctor of Philosophy Brain Tumour Research Centre Research Institute in Healthcare Sciences Faculty of Science and Engineering University of Wolverhampton November 2014 i DECLARATION This work or any part thereof has not previously been presented in any form to the University or to any other body whether for the purposes of assessment, publication or for any other purpose (unless otherwise indicated). Save for any express acknowledgments, references and/or bibliographies cited in the work, I confirm that the intellectual content of the work is the result of my own efforts and of no other person. The right of Anushree Singh to be identified as author of this work is asserted in accordance with ss.77 and 78 of the Copyright, Designs and Patents Act 1988. At this date copyright is owned by the author. Signature: Anushree Date: 30th November 2014 ii ABSTRACT The aim of the study was to identify molecular markers that can determine progression of low grade glioma. This was done using various approaches such as IDH1 and IDH2 mutation analysis, MGMT methylation analysis, copy number analysis using array comparative genomic hybridisation and identification of differentially expressed miRNAs using miRNA microarray analysis. IDH1 mutation was present at a frequency of 71% in low grade glioma and was identified as an independent marker for improved OS in a multivariate analysis, which confirms the previous findings in low grade glioma studies.
    [Show full text]
  • Comprehensive Sequence Analysis of Nine Usher Syndrome Genes in The
    Genotype-phenotype correlations J Med Genet: first published as 10.1136/jmedgenet-2011-100468 on 1 December 2011. Downloaded from ORIGINAL ARTICLE Comprehensive sequence analysis of nine Usher syndrome genes in the UK National Collaborative Usher Study Polona Le Quesne Stabej,1 Zubin Saihan,2,3 Nell Rangesh,4 Heather B Steele-Stallard,1 John Ambrose,5 Alison Coffey,5 Jenny Emmerson,5 Elene Haralambous,1 Yasmin Hughes,1 Karen P Steel,5 Linda M Luxon,4,6 Andrew R Webster,2,3 Maria Bitner-Glindzicz1,6 < Additional materials are ABSTRACT characterised by congenital, moderate to severe published online only. To view Background Usher syndrome (USH) is an autosomal hearing loss, with normal vestibular function and these files please visit the recessive disorder comprising retinitis pigmentosa, onset of RP around or after puberty; and type III journal online (http://jmg.bmj. fi com/content/49/1.toc). hearing loss and, in some cases, vestibular dysfunction. (USH3), de ned by postlingual progressive hearing 1 It is clinically and genetically heterogeneous with three loss and variable vestibular response together with Clinical and Molecular e 1 2 Genetics, Institute of Child distinctive clinical types (I III) and nine Usher genes RP. In addition there remain patients whose Health, UCL, London, UK identified. This study is a comprehensive clinical and disease does not fit into any of these three 2Institute of Ophthalmology, genetic analysis of 172 Usher patients and evaluates the subtypes, because of atypical audiovestibular or UCL, London, UK fi ‘ 3 contribution of digenic inheritance. retinal ndings, who are said to have atypical Moorfields Eye Hospital, Methods The genes MYO7A, USH1C, CDH23, PCDH15, ’ London, UK Usher syndrome .
    [Show full text]
  • TMC) Gene Family: Functional Clues from Hearing Loss and Epidermodysplasia Verruciformis૾
    Available online at www.sciencedirect.com R Genomics 82 (2003) 300–308 www.elsevier.com/locate/ygeno Characterization of the transmembrane channel-like (TMC) gene family: functional clues from hearing loss and epidermodysplasia verruciformis૾ Kiyoto Kurima,a Yandan Yang,a Katherine Sorber,a and Andrew J. Griffitha,b,* a Section on Gene Structure and Function, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Rockville, MD 20850, USA b Hearing Section, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Rockville, MD 20850, USA Received 10 March 2003; accepted 15 May 2003 Abstract Mutations of TMC1 cause deafness in humans and mice. TMC1 and a related gene, TMC2, are the founding members of a novel gene family. Here we describe six additional TMC paralogs (TMC3 to TMC8) in humans and mice, as well as homologs in other species. cDNAs spanning the full length of the predicted open reading frames of the mammalian genes were cloned and sequenced. All are strongly predicted to encode proteins with 6 to 10 transmembrane domains and a novel conserved 120-amino-acid sequence that we termed the TMC domain. TMC1, TMC2, and TMC3 comprise a distinct subfamily expressed at low levels, whereas TMC4 to TMC8 are expressed at higher levels in multiple tissues. TMC6 and TMC8 are identical to the EVER1 and EVER2 genes implicated in epidermodysplasia verruciformis, a recessive disorder comprising susceptibility to cutaneous human papilloma virus infections and associated nonmelanoma skin cancers, providing additional genetic and tissue systems in which to study the TMC gene family. © 2003 Elsevier Science (USA).
    [Show full text]
  • Supplementary Table 1: Adhesion Genes Data Set
    Supplementary Table 1: Adhesion genes data set PROBE Entrez Gene ID Celera Gene ID Gene_Symbol Gene_Name 160832 1 hCG201364.3 A1BG alpha-1-B glycoprotein 223658 1 hCG201364.3 A1BG alpha-1-B glycoprotein 212988 102 hCG40040.3 ADAM10 ADAM metallopeptidase domain 10 133411 4185 hCG28232.2 ADAM11 ADAM metallopeptidase domain 11 110695 8038 hCG40937.4 ADAM12 ADAM metallopeptidase domain 12 (meltrin alpha) 195222 8038 hCG40937.4 ADAM12 ADAM metallopeptidase domain 12 (meltrin alpha) 165344 8751 hCG20021.3 ADAM15 ADAM metallopeptidase domain 15 (metargidin) 189065 6868 null ADAM17 ADAM metallopeptidase domain 17 (tumor necrosis factor, alpha, converting enzyme) 108119 8728 hCG15398.4 ADAM19 ADAM metallopeptidase domain 19 (meltrin beta) 117763 8748 hCG20675.3 ADAM20 ADAM metallopeptidase domain 20 126448 8747 hCG1785634.2 ADAM21 ADAM metallopeptidase domain 21 208981 8747 hCG1785634.2|hCG2042897 ADAM21 ADAM metallopeptidase domain 21 180903 53616 hCG17212.4 ADAM22 ADAM metallopeptidase domain 22 177272 8745 hCG1811623.1 ADAM23 ADAM metallopeptidase domain 23 102384 10863 hCG1818505.1 ADAM28 ADAM metallopeptidase domain 28 119968 11086 hCG1786734.2 ADAM29 ADAM metallopeptidase domain 29 205542 11085 hCG1997196.1 ADAM30 ADAM metallopeptidase domain 30 148417 80332 hCG39255.4 ADAM33 ADAM metallopeptidase domain 33 140492 8756 hCG1789002.2 ADAM7 ADAM metallopeptidase domain 7 122603 101 hCG1816947.1 ADAM8 ADAM metallopeptidase domain 8 183965 8754 hCG1996391 ADAM9 ADAM metallopeptidase domain 9 (meltrin gamma) 129974 27299 hCG15447.3 ADAMDEC1 ADAM-like,
    [Show full text]
  • USHIC, CDH23 and TMIE
    Non-Syndromic Hearing Impairment in India: High Allelic Heterogeneity among Mutations in TMPRSS3, TMC1, USHIC, CDH23 and TMIE Aparna Ganapathy1, Nishtha Pandey1, C. R. Srikumari Srisailapathy2, Rajeev Jalvi3, Vikas Malhotra4, Mohan Venkatappa1, Arunima Chatterjee1, Meenakshi Sharma1, Rekha Santhanam1, Shelly Chadha4, Arabandi Ramesh2, Arun K. Agarwal4, Raghunath R. Rangasayee3, Anuranjan Anand1* 1 Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India, 2 Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, Chennai, India, 3 Department of Audiology, Ali Yavar Jung National Institute for the Hearing Handicapped, Mumbai, India, 4 Department of ENT, Maulana Azad Medical College, New Delhi, India Abstract Mutations in the autosomal genes TMPRSS3, TMC1, USHIC, CDH23 and TMIE are known to cause hereditary hearing loss. To study the contribution of these genes to autosomal recessive, non-syndromic hearing loss (ARNSHL) in India, we examined 374 families with the disorder to identify potential mutations. We found four mutations in TMPRSS3, eight in TMC1, ten in USHIC, eight in CDH23 and three in TMIE. Of the 33 potentially pathogenic variants identified in these genes, 23 were new and the remaining have been previously reported. Collectively, mutations in these five genes contribute to about one-tenth of ARNSHL among the families examined. New mutations detected in this study extend the allelic heterogeneity of the genes and provide several additional variants for structure-function correlation studies. These findings have implications for early DNA-based detection of deafness and genetic counseling of affected families in the Indian subcontinent. Citation: Ganapathy A, Pandey N, Srisailapathy CRS, Jalvi R, Malhotra V, et al.
    [Show full text]
  • TMHS Is an Integral Component of the Mechanotransduction Machinery of Cochlear Hair Cells
    TMHS Is an Integral Component of the Mechanotransduction Machinery of Cochlear Hair Cells Wei Xiong,1 Nicolas Grillet,1 Heather M. Elledge,1 Thomas F.J. Wagner,1 Bo Zhao,1 Kenneth R. Johnson,2 Piotr Kazmierczak,1 and Ulrich Mu¨ller1,* 1The Dorris Neuroscience Center, Department of Cell Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA 2The Jackson Laboratory, Bar Harbor, ME 04609, USA *Correspondence: [email protected] http://dx.doi.org/10.1016/j.cell.2012.10.041 SUMMARY deflection of the stereociliary bundles, which directly control the activity of the mechanotransduction channels in stereocilia. Hair cells are mechanosensors for the perception of It is thought that tip links, fine extracellular filaments that connect sound, acceleration, and fluid motion. Mechano- the tips of neighboring stereocilia, transmit tension force onto transduction channels in hair cells are gated by tip the transduction channels (Gillespie and Mu¨ ller, 2009). links, which connect the stereocilia of a hair cell in In recent years, significant progress has been made in the direction of their mechanical sensitivity. The the identification of components of the mechanotransduction molecular constituents of the mechanotransduction machinery of hair cells (Figure 1A). These studies have shown that tip links are formed by CDH23 homodimers that interact channels of hair cells are not known. Here, we show with PCDH15 homodimers to form the upper and lower parts that mechanotransduction is impaired in mice lack- of tip links (Ahmed et al., 2006; Kazmierczak et al., 2007; ing the tetraspan TMHS. TMHS binds to the tip-link Siemens et al., 2004; So¨ llner et al., 2004).
    [Show full text]
  • Improved TMC1 Gene Therapy Restores Hearing and Balance in Mice with Genetic Inner Ear Disorders
    Corrected: Publisher correction ARTICLE https://doi.org/10.1038/s41467-018-08264-w OPEN Improved TMC1 gene therapy restores hearing and balance in mice with genetic inner ear disorders Carl A. Nist-Lund1, Bifeng Pan 1,2, Amy Patterson1, Yukako Asai1,2, Tianwen Chen3, Wu Zhou3, Hong Zhu3, Sandra Romero4, Jennifer Resnik2,4, Daniel B. Polley2,4, Gwenaelle S. Géléoc1,2 & Jeffrey R. Holt1,2,5 Fifty percent of inner ear disorders are caused by genetic mutations. To develop treatments for genetic inner ear disorders, we designed gene replacement therapies using synthetic 1234567890():,; adeno-associated viral vectors to deliver the coding sequence for Transmembrane Channel- Like (Tmc) 1 or 2 into sensory hair cells of mice with hearing and balance deficits due to mutations in Tmc1 and closely related Tmc2. Here we report restoration of function in inner and outer hair cells, enhanced hair cell survival, restoration of cochlear and vestibular function, restoration of neural responses in auditory cortex and recovery of behavioral responses to auditory and vestibular stimulation. Secondarily, we find that inner ear Tmc gene therapy restores breeding efficiency, litter survival and normal growth rates in mouse models of genetic inner ear dysfunction. Although challenges remain, the data suggest that Tmc gene therapy may be well suited for further development and perhaps translation to clinical application. 1 Department of Otolaryngology and F.M. Kirby Neurobiology Center, Boston Children’s Hospital, 300 Longwood Avenue, Boston, MA 02115, USA. 2 Department of Otolaryngology, Harvard Medical School, Boston, MA 02139, USA. 3 Department of Otolaryngology and Communicative Sciences, University of Mississippi Medical Center, Jackson, MS 39216, USA.
    [Show full text]
  • 1 Structural Studies of a Protocadherin-15 Fragment Essential for Hearing
    Structural Studies of a Protocadherin-15 Fragment Essential for Hearing A thesis presented By Conghui Chen To The Committee on Degrees in Chemistry ad Biochemistry In partial fulfillment of the requirements For a degree of Bachelor of Science with Research Distinction In the field of Biochemistry Research Advisor: Dr. Marcos Sotomayor, Assistant Professor of Department of Chemistry and Biochemistry Defense Committee: Dr. John Shimko, Chemistry Lecturer of Department of Chemistry and Biochemistry The Ohio State University Columbus, Ohio April 13th, 2016 1 Statement of Research I conducted the research presented in this thesis under the professional guidance of Dr. Marcos Sotomayor of The Ohio State University Main Campus Chemistry and Biochemistry Department. I joined the Sotomayor lab in August of 2013, during my second year at the university. I was trained in the process of protein purification and cell culture by visiting graduate student Deryanur Kilic in conjunction with Dr. Sotomayor. Dr. Sotomayor offered knowledgeable tutelage in designing and performing the experiments, analyzing data, and the writing of this thesis. All molecular modeling and analysis was performed with the guidance and assistance from Dr. Marcos Sotomayor and Dr. Raul Araya-Secchi. My research was generously funded by The Ohio State University Chemistry and Biochemistry Undergraduate Research Scholarship from autumn 2013 until spring 2015. I performed research as part of the Biochemistry 4998 and 4999 courses as a requirement for the completion of the thesis. 2 Abstract Sound travels through the external and middle ear to the fluid-filled cochlea where mechanosensitive hair cells transform it into electrochemical signals. On the apical side of each hair cell, a set of hair-like protrusions, called stereocilia form a bundle with filamentous connections (tip links) that are essential for hearing.
    [Show full text]
  • Elucidating Biological Roles of Novel Murine Genes in Hearing Impairment in Africa
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 19 September 2019 doi:10.20944/preprints201909.0222.v1 Review Elucidating Biological Roles of Novel Murine Genes in Hearing Impairment in Africa Oluwafemi Gabriel Oluwole,1* Abdoulaye Yal 1,2, Edmond Wonkam1, Noluthando Manyisa1, Jack Morrice1, Gaston K. Mazanda1 and Ambroise Wonkam1* 1Division of Human Genetics, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Observatory, Cape Town, South Africa. 2Department of Neurology, Point G Teaching Hospital, University of Sciences, Techniques and Technology, Bamako, Mali. *Correspondence to: [email protected]; [email protected] Abstract: The prevalence of congenital hearing impairment (HI) is highest in Africa. Estimates evaluated genetic causes to account for 31% of HI cases in Africa, but the identification of associated causative genes mutations have been challenging. In this study, we reviewed the potential roles, in humans, of 38 novel genes identified in a murine study. We gathered information from various genomic annotation databases and performed functional enrichment analysis using online resources i.e. genemania and g.proflier. Results revealed that 27/38 genes are express mostly in the brain, suggesting additional cognitive roles. Indeed, HERC1- R3250X had been associated with intellectual disability in a Moroccan family. A homozygous 216-bp deletion in KLC2 was found in two siblings of Egyptian descent with spastic paraplegia. Up to 27/38 murine genes have link to at least a disease, and the commonest mode of inheritance is autosomal recessive (n=8). Network analysis indicates that 20 other genes have intermediate and biological links to the novel genes, suggesting their possible roles in HI.
    [Show full text]
  • Engineering New Balancer Chromosomes in C. Elegans Via
    www.nature.com/scientificreports OPEN Engineering new balancer chromosomes in C. elegans via CRISPR/Cas9 Received: 19 May 2016 Satoru Iwata1, Sawako Yoshina1, Yuji Suehiro1, Sayaka Hori1 & Shohei Mitani1,2 Accepted: 02 September 2016 Balancer chromosomes are convenient tools used to maintain lethal mutations in heterozygotes. We Published: 21 September 2016 established a method for engineering new balancers in C. elegans by using the CRISPR/Cas9 system in a non-homologous end-joining mutant. Our studies will make it easier for researchers to maintain lethal mutations and should provide a path for the development of a system that generates rearrangements at specific sites of interest to model and analyse the mechanisms of action of genes. Genetic balancers (including inversions, translocations and crossover-suppressors) are essential tools to maintain lethal or sterile mutations in heterozygotes. Recombination is suppressed within these chromosomal rearrange- ments. However, despite efforts to isolate genetic balancers since 19781–5, approximately 15% (map units) of the C. elegans genome has not been covered6 (Supplementary Fig. 1). Because the chromosomal rearrangements gen- erated by gamma-ray and X-ray mutagenesis are random, it is difficult to modify specific chromosomal regions. Here, we used the CRISPR/Cas9 genome editing system to solve this problem. The CRISPR/Cas9 system has enabled genomic engineering of specific DNA sequences and has been successfully applied to the generation of gene knock-outs and knock-ins in humans, rats, mice, zebrafish, flies and nematodes7. Recently, the CRISPR/ Cas9 system has been shown to induce inversions and translocations in human cell lines and mouse somatic cells8–10.
    [Show full text]