1
|
De-la-Torre P, Choudhary D, Araya-Secchi R, Narui Y, Sotomayor M. A Mechanically Weak Extracellular Membrane-Adjacent Domain Induces Dimerization of Protocadherin-15. Biophys J 2018; 115:2368-2385. [PMID: 30527337 PMCID: PMC6302040 DOI: 10.1016/j.bpj.2018.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/01/2018] [Accepted: 11/05/2018] [Indexed: 10/27/2022] Open
Abstract
The cadherin superfamily of proteins is defined by the presence of extracellular cadherin (EC) "repeats" that engage in protein-protein interactions to mediate cell-cell adhesion, cell signaling, and mechanotransduction. The extracellular domains of nonclassical cadherins often have a large number of EC repeats along with other subdomains of various folds. Protocadherin-15 (PCDH15), a protein component of the inner-ear tip link filament essential for mechanotransduction, has 11 EC repeats and a membrane adjacent domain (MAD12) of atypical fold. Here we report the crystal structure of a pig PCDH15 fragment including EC10, EC11, and MAD12 in a parallel dimeric arrangement. MAD12 has a unique molecular architecture and folds as a ferredoxin-like domain similar to that found in the nucleoporin protein Nup54. Analytical ultracentrifugation experiments along with size-exclusion chromatography coupled to multiangle laser light scattering and small-angle x-ray scattering corroborate the crystallographic dimer and show that MAD12 induces parallel dimerization of PCDH15 near its membrane insertion point. In addition, steered molecular dynamics simulations suggest that MAD12 is mechanically weak and may unfold before tip-link rupture. Sequence analyses and structural modeling predict the existence of similar domains in cadherin-23, protocadherin-24, and the "giant" FAT and CELSR cadherins, indicating that some of them may also exhibit MAD-induced parallel dimerization.
Collapse
Affiliation(s)
- Pedro De-la-Torre
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio
| | - Deepanshu Choudhary
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio
| | - Raul Araya-Secchi
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio; Structural Biophysics, Section for Neutron and X-ray Science, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Yoshie Narui
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio
| | - Marcos Sotomayor
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio.
| |
Collapse
|
2
|
Fritzsch B, Elliott KL. Gene, cell, and organ multiplication drives inner ear evolution. Dev Biol 2017; 431:3-15. [PMID: 28866362 DOI: 10.1016/j.ydbio.2017.08.034] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 04/27/2017] [Accepted: 08/25/2017] [Indexed: 12/14/2022]
Abstract
We review the development and evolution of the ear neurosensory cells, the aggregation of neurosensory cells into an otic placode, the evolution of novel neurosensory structures dedicated to hearing and the evolution of novel nuclei in the brain and their input dedicated to processing those novel auditory stimuli. The evolution of the apparently novel auditory system lies in duplication and diversification of cell fate transcription regulation that allows variation at the cellular level [transforming a single neurosensory cell into a sensory cell connected to its targets by a sensory neuron as well as diversifying hair cells], organ level [duplication of organ development followed by diversification and novel stimulus acquisition] and brain nuclear level [multiplication of transcription factors to regulate various neuron and neuron aggregate fate to transform the spinal cord into the unique hindbrain organization]. Tying cell fate changes driven by bHLH and other transcription factors into cell and organ changes is at the moment tentative as not all relevant factors are known and their gene regulatory network is only rudimentary understood. Future research can use the blueprint proposed here to provide both the deeper molecular evolutionary understanding as well as a more detailed appreciation of developmental networks. This understanding can reveal how an auditory system evolved through transformation of existing cell fate determining networks and thus how neurosensory evolution occurred through molecular changes affecting cell fate decision processes. Appreciating the evolutionary cascade of developmental program changes could allow identifying essential steps needed to restore cells and organs in the future.
Collapse
Affiliation(s)
- Bernd Fritzsch
- University of Iowa, Department of Biology, Iowa City, IA 52242, United States.
| | - Karen L Elliott
- University of Iowa, Department of Biology, Iowa City, IA 52242, United States
| |
Collapse
|
3
|
Rengasamy P. Critical Periods of Development in Teratology. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2015. [DOI: 10.1007/7653_2015_55] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
4
|
Ou HC, Santos F, Raible DW, Simon JA, Rubel EW. Drug screening for hearing loss: using the zebrafish lateral line to screen for drugs that prevent and cause hearing loss. Drug Discov Today 2010; 15:265-71. [PMID: 20096805 DOI: 10.1016/j.drudis.2010.01.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2009] [Revised: 12/01/2009] [Accepted: 01/06/2010] [Indexed: 12/17/2022]
Abstract
Several animal models have been used for the study of mechanosensory hair cells and hearing loss. Because of the difficulty of tissue acquisition and large animal size, these traditional models are impractical for high-throughput screening. The zebrafish has emerged as a powerful animal model for screening drugs that cause and prevent hair cell death. The unique characteristics of the zebrafish enable rapid in vivo imaging of hair cells and hair cell death. We have used this model to screen for and identify multiple drugs that protect hair cells from aminoglycoside-induced death. The identification of multiple drugs and drug-like compounds that inhibit multiple hair cell death pathways might enable the development of protective cocktails to achieve complete hair cell protection.
Collapse
Affiliation(s)
- Henry C Ou
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Box 357923, Seattle, WA 98195, USA.
| | | | | | | | | |
Collapse
|
5
|
Li A, Xue J, Peterson EH. Architecture of the mouse utricle: macular organization and hair bundle heights. J Neurophysiol 2007; 99:718-33. [PMID: 18046005 DOI: 10.1152/jn.00831.2007] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hair bundles are critical to mechanotransduction by vestibular hair cells, but quantitative data are lacking on vestibular bundles in mice or other mammals. Here we quantify bundle heights and their variation with macular locus and hair cell type in adult mouse utricular macula. We also determined that macular organization differs from previous reports. The utricle has approximately 3,600 hair cells, half on each side of the line of polarity reversal (LPR). A band of low hair cell density corresponds to a band of calretinin-positive calyces, i.e., the striola. The relation between the LPR and the striola differs from previous reports in two ways. First, the LPR lies lateral to the striola instead of bisecting it. Second, the LPR follows the striolar trajectory anteriorly, but posteriorly it veers from the edge of the striola to reach the posterior margin of the macula. Consequently, more utricular bundles are oriented mediolaterally than previously supposed. Three hair cell classes are distinguished in calretinin-stained material: type II hair cells, type ID hair cells contacting calretinin-negative (dimorphic) afferents, and type IC hair cells contacting calretinin-positive (calyceal) afferents. They differ significantly on most bundle measures. Type II bundles have short stereocilia. Type IC bundles have kinocilia and stereocilia of similar heights, i.e., KS ratios (ratio of kinocilium to stereocilia heights) approximately 1, unlike other receptor classes. In contrast to these class-specific differences, bundles show little regional variation except that KS ratios are lowest in the striola. These low KS ratios suggest that bundle stiffness is greater in the striola than in the extrastriola.
Collapse
Affiliation(s)
- A Li
- Department of Biological Sciences and Neuroscience Program, Ohio University, Athens, OH 45701, USA
| | | | | |
Collapse
|
6
|
Hayashi T, Cunningham D, Bermingham-McDonogh O. Loss of Fgfr3 leads to excess hair cell development in the mouse organ of Corti. Dev Dyn 2007; 236:525-33. [PMID: 17117437 DOI: 10.1002/dvdy.21026] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Previous studies have demonstrated the importance of FGF signaling at several stages in the development of the cochlea. At early stages of embryogenesis, Fgfr1, Fgfr2, and several FGFs are critical for both the induction of the otic vesicle and the initial development of the sensory epithelium. At late stages of cochlear development, Fgfr3 is necessary for the development of the tunnel of Corti. To determine the stage of development when Fgfr3 is required, we examined the expression of Fgfr3 and Fgf8 at various developmental stages. We also re-examined the Fgfr3 -/- mouse with additional markers for developing supporting cells. We confirmed the previous analysis of the Fgfr3 -/- mice, indicating that there are deficiencies in support cell differentiation. Specifically, we find that the inner pillar cell never develops, while the outer pillar cell is stalled in its differentiation. In addition, we found an extra row of outer hair cells, and accompanying Deiters' cells, in the apical two thirds of the organ of Corti in the Fgfr3 mutant. Thus, in addition to controlling the fate decision between pillar cells and Deiters' cells, we find that Fgfr3 also regulates the width of the sensory epithelium.
Collapse
Affiliation(s)
- Toshinori Hayashi
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-HNS, University of Washington, Seattle, Washington 98195, USA
| | | | | |
Collapse
|
7
|
Schwander M, Sczaniecka A, Grillet N, Bailey JS, Avenarius M, Najmabadi H, Steffy BM, Federe GC, Lagler EA, Banan R, Hice R, Grabowski-Boase L, Keithley EM, Ryan AF, Housley GD, Wiltshire T, Smith RJH, Tarantino LM, Müller U. A forward genetics screen in mice identifies recessive deafness traits and reveals that pejvakin is essential for outer hair cell function. J Neurosci 2007; 27:2163-75. [PMID: 17329413 PMCID: PMC6673480 DOI: 10.1523/jneurosci.4975-06.2007] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Deafness is the most common form of sensory impairment in the human population and is frequently caused by recessive mutations. To obtain animal models for recessive forms of deafness and to identify genes that control the development and function of the auditory sense organs, we performed a forward genetics screen in mice. We identified 13 mouse lines with defects in auditory function and six lines with auditory and vestibular defects. We mapped several of the affected genetic loci and identified point mutations in four genes. Interestingly, all identified genes are expressed in mechanosensory hair cells and required for their function. One mutation maps to the pejvakin gene, which encodes a new member of the gasdermin protein family. Previous studies have described two missense mutations in the human pejvakin gene that cause nonsyndromic recessive deafness (DFNB59) by affecting the function of auditory neurons. In contrast, the pejvakin allele described here introduces a premature stop codon, causes outer hair cell defects, and leads to progressive hearing loss. We also identified a novel allele of the human pejvakin gene in an Iranian pedigree that is afflicted with progressive hearing loss. Our findings suggest that the mechanisms of pathogenesis associated with pejvakin mutations are more diverse than previously appreciated. More generally, our findings demonstrate that recessive screens in mice are powerful tools for identifying genes that control the development and function of mechanosensory hair cells and cause deafness in humans, as well as generating animal models for disease.
Collapse
MESH Headings
- Animals
- Base Sequence
- Chromosome Mapping
- Deafness/chemically induced
- Deafness/genetics
- Disease Models, Animal
- Ethylnitrosourea/analogs & derivatives
- Female
- Genes, Recessive
- Genetic Testing
- Hair Cells, Auditory, Outer/cytology
- Hair Cells, Auditory, Outer/pathology
- Hair Cells, Auditory, Outer/physiology
- Humans
- Male
- Membrane Proteins/genetics
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mutagens
- Neoplasm Proteins/metabolism
- Pedigree
- Point Mutation
- Psychomotor Agitation/genetics
- Sequence Alignment
Collapse
Affiliation(s)
- Martin Schwander
- Department of Cell Biology, Institute for Childhood and Neglected Disease, The Scripps Research Institute, La Jolla, California 92037
| | - Anna Sczaniecka
- Department of Cell Biology, Institute for Childhood and Neglected Disease, The Scripps Research Institute, La Jolla, California 92037
| | - Nicolas Grillet
- Department of Cell Biology, Institute for Childhood and Neglected Disease, The Scripps Research Institute, La Jolla, California 92037
| | - Janice S. Bailey
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Matthew Avenarius
- Department of Otolaryngology and the Interdepartmental Ph.D. Genetic Program, The University of Iowa, Iowa City, Iowa 52242
| | - Hossein Najmabadi
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Brian M. Steffy
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Glenn C. Federe
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Erica A. Lagler
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Raheleh Banan
- Department of Cell Biology, Institute for Childhood and Neglected Disease, The Scripps Research Institute, La Jolla, California 92037
| | - Rudy Hice
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | | | - Elisabeth M. Keithley
- Departments of Surgery and Neurosciences, University of California, San Diego School of Medicine and Veterans Affairs Medical Center, La Jolla, California 92093, and
| | - Allen F. Ryan
- Departments of Surgery and Neurosciences, University of California, San Diego School of Medicine and Veterans Affairs Medical Center, La Jolla, California 92093, and
| | - Gary D. Housley
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Tim Wiltshire
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Richard J. H. Smith
- Department of Otolaryngology and the Interdepartmental Ph.D. Genetic Program, The University of Iowa, Iowa City, Iowa 52242
| | - Lisa M. Tarantino
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Ulrich Müller
- Department of Cell Biology, Institute for Childhood and Neglected Disease, The Scripps Research Institute, La Jolla, California 92037
| |
Collapse
|
8
|
Calderon A, Derr A, Stagner BB, Johnson KR, Martin G, Noben-Trauth K. Cochlear developmental defect and background-dependent hearing thresholds in the Jackson circler (jc) mutant mouse. Hear Res 2006; 221:44-58. [PMID: 16962269 DOI: 10.1016/j.heares.2006.07.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Revised: 07/19/2006] [Accepted: 07/20/2006] [Indexed: 11/22/2022]
Abstract
Jackson circler (jc) is a spontaneous, recessive mouse mutation that results in circling behavior and an impaired acoustic startle response. In this study, we refined the phenotypic and genetic parameters of the original jc mutation and characterized a new mutant allele, jc(2J). In open-field behavior tests, homozygous jc mutants exhibited abnormal circling and ambulatory behavior that was indistinguishable from that of phenotypically similar mutants with defects in the vestibule of the inner ear. The jc/jc and jc(2J)/jc(2J) mice had stable elevated auditory-evoked brainstem response (ABR) thresholds at the 16kHz stimulus of 88+/-9dB sound pressure levels (SPL) and 43+/-11dB SPL, respectively. Peak latencies and peak time intervals were normal in jc mutants. The jc mice showed no measurable distortion-product otoacoustic emissions (DPOAEs) above the system noise floor. In the mutant cochlea, the apical turn failed to form due to the developmental growth arrest of the cochlear duct at the level of the first turn at gestational day 13.5. In a large intrasubspecific intercross, jc localized to a 0.2cM interval at position 25cM on chromosome 10, which is homologous to the human 6q21 region. On CZECHII/Ei and CAST/Ei backgrounds jc/jc mutant hearing thresholds at the 16kHz stimulus were significantly lower than those observed on the C57BL/6J background, with means of 62+/-22dB SPL and 55+/-18dB SPL, respectively. Genome-wide linkage scans of backcross, intercross, and congenic progeny revealed a complex pattern of genetic and stochastic effects.
Collapse
Affiliation(s)
- Alfredo Calderon
- Section on Neurogenetics, Laboratory of Molecular Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, 5 Research Court, Rockville, MD 20850, USA
| | | | | | | | | | | |
Collapse
|
9
|
Seiler C, Ben-David O, Sidi S, Hendrich O, Rusch A, Burnside B, Avraham KB, Nicolson T. Myosin VI is required for structural integrity of the apical surface of sensory hair cells in zebrafish. Dev Biol 2004; 272:328-38. [PMID: 15282151 DOI: 10.1016/j.ydbio.2004.05.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Revised: 04/30/2004] [Accepted: 05/04/2004] [Indexed: 10/26/2022]
Abstract
Unconventional myosins have been associated with hearing loss in humans, mice, and zebrafish. Mutations in myosin VI cause both recessive and dominant forms of nonsyndromic deafness in humans and deafness in Snell's waltzer mice associated with abnormal fusion of hair cell stereocilia. Although myosin VI has been implicated in diverse cellular processes such as vesicle trafficking and epithelial morphogenesis, the role of this protein in the sensory hair cells remains unclear. To investigate the function of myosin VI in zebrafish, we cloned and examined the expression pattern of myosin VI, which is duplicated in the zebrafish genome. One duplicate, myo6a, is expressed in a ubiquitous pattern during early development and at later stages, and is highly expressed in the brain, gut, and kidney. myo6b, on the other hand, is predominantly expressed in the sensory epithelium of the ear and lateral line at all developmental stages examined. Both molecules have different splice variants expressed in these tissues. Using a candidate gene approach, we show that myo6b is satellite, a gene responsible for auditory/vestibular defects in zebrafish larvae. Examination of hair cells in satellite mutants revealed that stereociliary bundles are irregular and disorganized. At the ultrastructural level, we observed that the apical surface of satellite mutant hair cells abnormally protrudes above the epithelium and the membrane near the base of the stereocilia is raised. At later stages, stereocilia fused together. We conclude that zebrafish myo6b is required for maintaining the integrity of the apical surface of hair cells, suggesting a conserved role for myosin VI in regulation of actin-based interactions with the plasma membrane.
Collapse
Affiliation(s)
- Christoph Seiler
- Max-Planck-Institut fur Entwicklungsbiologie, 72076 Tubingen, Germany
| | | | | | | | | | | | | | | |
Collapse
|