The maturation of the mechanoelectrical transducer apparatus of auditory hair cells requires a critical period of pre-hearing spiking activity
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB56241 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Sensory-independent Ca2+ spiking activity is crucial for the development of mammalian sensory systems. In the cochlea, spontaneous Ca2+ action potentials (APs) are present in the pre-hearing inner hair cells (IHCs), the frequency and pattern of which is modulated by ATP-dependent intercellular Ca2+ waves in the non-sensory cells. It remains unknown whether both these Ca2+-dependent signalling mechanisms in the cochlea are required for the functional maturation of the IHCs. We found that the intrinsic Ca2+ AP activity, but not that triggered by Ca2+ signalling in the non-sensory cells, regulates the maturation and maintenance of the stereociliary hair bundle in IHCs. We used a mouse model in which the potassium channel Kir2.1 is reversibly overexpressed in IHCs in vivo. Kir2.1 overexpression (Kir2.1-OE mice) prevented spontaneous Ca2+ spikes in IHCs, but not their modulation by ATP-induced signalling from non-sensory cells. Without spontaneous Ca2+ APs, mechanoelectrical transduction in IHCs disappeared prior the onset of hearing at P12 due to the progressive loss of stereocilia and their fusion. RNA-sequencing data showed that several pathways, including those involved in morphogenesis, actin-filament based processes, and Rho-GTPase signalling, were upregulated during the second postnatal week. By manipulating the in vivo expression of Kir2.1 channels, we identified the second post-natal week as the “critical point” after which spontaneous Ca2+ APs are required for proper hair bundle maintenance. We showed that the final stage of IHC maturation is finely regulated by their intrinsic electrical activity just before sound-induced sensory driven activity.
2023-01-01 | GSE215951 | GEO
Project description:Spontaneous firing activity in pre-hearing inner hair cells regulates the maturation of the mechanoelectrical transducer apparatus over a critical time-period
| PRJNA891338 | ENA
Project description:The development of neural circuits relies on spontaneous electrical activity that occurs during immature stages of development. In the developing mammalian auditory system, spontaneous calcium action potentials are generated by inner hair cells (IHCs), which form the primary sensory synapse. It remains unknown whether this electrical activity is required for the functional maturation of the auditory system. We found that sensory-independent electrical activity controls synaptic maturation in IHCs. We used a mouse model in which the potassium channel SK2 is normally overexpressed, but can be modulated in vivo using doxycycline. SK2 overexpression affected the frequency and duration of spontaneous action potentials, which prevented the development of the Ca(2+)-sensitivity of vesicle fusion at IHC ribbon synapses, without affecting their morphology or general cell development. By manipulating the in vivo expression of SK2 channels, we identified the "critical period" during which spiking activity influences IHC synaptic maturation. Here we provide direct evidence that IHC development depends upon a specific temporal pattern of calcium spikes before sound-driven neuronal activity.
| S-EPMC3666720 | biostudies-literature
Project description:Age-related hearing (ARHL) loss affects a large part of the human population with a major impact on our aging societies. Yet, underlying mechanisms are not understood, and no validated therapy or prevention exists. NADPH oxidases (NOX), are important sources of reactive oxygen species (ROS) in the cochlea and might therefore be involved in the pathogenesis of ARHL. Here we investigate ARHL in a mouse model. Wild type mice showed early loss of hearing and cochlear integrity, while animals deficient in the NOX subunit p22phox remained unaffected up to six months. Genes of the excitatory pathway were down-regulated in p22phox-deficient auditory neurons. Our results demonstrate that NOX activity leads to upregulation of genes of the excitatory pathway, to excitotoxic cochlear damage, and ultimately to ARHL. In the absence of functional NOXs, aging mice conserve hearing and cochlear morphology. Our study offers new insights into pathomechanisms and future therapeutic targets of ARHL.
2020-12-18 | E-MTAB-8668 | biostudies-arrayexpress
Project description:A large number of congenital hearing loss cases have an unknown genetic etiology. So far, transcriptomic approaches have successfully identified many candidate regulators of otic development, little is known about the abundance of their protein products during the development of the inner eat. Herein we used a multiplexed quantitative mass spectrometry-based proteomic approach to determine temporal trends in protein abundances during inner ear (otic) development in Xenopus. Wild type Xenopus embryos were cultured to larval stages and their otic tissues were manually dissected at five stages that represent that represent key transitions in otic morphology. The samples were processed using a bottom-up proteomic workflow and analyzed using LC-MS3.The analysis revealed dynamic expression of proteins related to cytoskeletal regulation, integrin signaling, and the extracellular matrix as inner ear structures developed. We correlated the dynamically regulated proteins in our dataset with previously published putative downstream targets of syndromic hearing loss genes SIX1 and CHD7 to identify novel candidate genes for congenital hearing loss.
2023-10-24 | PXD041991 | Pride
Project description:115 dB SPL of noise exposure for 2 hours causes high threshold shift at day 1 and recovers rapidly at day 3. Microarray was performed to identify up or down-regulated genes during rapid recovery of hearing.
2024-07-08 | GSE271449 | GEO
Project description:Presbycusis – age-related hearing loss – is the number one communicative disorder of our aged population. Here we analyzed gene expression for a set of GABA receptors in the cochlea of aging CBA mice using the Affymetrix GeneChip MOE430A. Functional phenotypic hearing measures distortion-product otoacoustic emission (DPOAE) amplitudes (four age groups) were made. The gene expression changes from RMA normalized microarray data (40 replicates) were first subjected to one-way ANOVA, and then linear regression was performed. In addition, the log signal ratio was converted to fold change, and selected gene expression changes were confirmed by relative real-time PCR. Major findings: expression of GABA-A receptor subunit 6was upregulated with age and hearing loss, whereas subunit 1 was repressed. In addition, GABA-A receptor associated protein like-1 and GABA-A receptor associated protein like-2 were strongly downregulated with age and hearing impairment. Lastly, gene expression measures were correlated with pathway/network relationships relevant to the inner ear using Pathway Architect, to identify key pathways consistent with the gene expression changes observed. In the study of expression changes GABA receptors in the in cochlea of young adult and aging presbycusis mice total of forty chips were used. The normal aging mice were in four groups young adults controls with good hearing (8 mice, 8 MOE430A GeneChips), Middle aged group with good hearing ( 17 mice, 17 MOE430A GeneChips), Mild Presbycusis (old) with limited hearing loss (9 mice, 9 MOE430A GeneChips) and Severe Presbycusis (old) (6 mice, 6 MOE430A GeneChips). Each Mice cochlea to each GeneChips, Samples was not pooled. The hearing potential evidence of each mouse is accompanied with each mice DPOAE amplitude.
2013-08-06 | E-GEOD-49543 | biostudies-arrayexpress
Project description:Alternative splicing contributes to gene expression dynamics in many tissues, yet its role in auditory development remains unclear. We performed whole exome sequencing in individuals with sensorineural hearing loss (SNHL) and identified pathogenic mutations in Epithelial Splicing Regulatory Protein 1 (ESRP1). Patient derived induced pluripotent stem cells showed alternative splicing defects consistent with impaired ESRP1 function. To determine how mutations in ESRP1 cause hearing loss we evaluated Esrp1-/- mouse embryos and uncovered alterations in cochlear morphogenesis, auditory hair cell differentiation and cell fate specification. Transcriptome analysis revealed impaired expression and splicing of genes with essential roles in inner ear development and auditory function. In particular, aberrant splicing of Fgfr2 blocked stria vascularis formation due to erroneous ligand usage, which was corrected by reducing Fgf9 gene dosage. These findings implicate mutations in ESRP1 as a novel cause of SNHL and demonstrate the complex interplay between alternative splicing, inner ear development, and auditory function.
2017-09-01 | GSE90821 | GEO
Project description:Presbycusis – age-related hearing loss – is the number one communicative disorder of our aged population. Here we analyzed gene expression for a set of GABA receptors in the cochlea of aging CBA mice using the Affymetrix GeneChip MOE430A. Functional phenotypic hearing measures distortion-product otoacoustic emission (DPOAE) amplitudes (four age groups) were made. The gene expression changes from RMA normalized microarray data (40 replicates) were first subjected to one-way ANOVA, and then linear regression was performed. In addition, the log signal ratio was converted to fold change, and selected gene expression changes were confirmed by relative real-time PCR. Major findings: expression of GABA-A receptor subunit 6was upregulated with age and hearing loss, whereas subunit 1 was repressed. In addition, GABA-A receptor associated protein like-1 and GABA-A receptor associated protein like-2 were strongly downregulated with age and hearing impairment. Lastly, gene expression measures were correlated with pathway/network relationships relevant to the inner ear using Pathway Architect, to identify key pathways consistent with the gene expression changes observed.
2013-08-06 | GSE49543 | GEO
Project description:Congenital hearing loss is a common chronic condition affecting children in both developed and developing nations. In many cases, congenital hearing loss is ultimately attributed to viral infection, most often by cytomegalovirus (CMV), but also in Congenital Zika Syndrome (CZS). The mechanisms by which CMV and ZIKV virus cause these cranial developmental defects have not been elucidated. Inner ear development has been particularly difficult to study, given the inaccessibility and scarcity of the tissue in animal models or on human autopsy; however, it is now possible to culture stem-cell derived otic progenitor cells (OPCs). Here we describe successful in-vitro infection of OPCs with either CMV or ZIKV. We find that ZIKV infection rapidly and strongly induces the expression of type I IFN and inflammatory genes, while simultaneously decreasing otic cell viability in culture that is at least in part attributable to apoptosis. In contrast, CMV infection did not appear to elicit either of these effects and instead demonstrated a clear dysregulation of the expression of many key genes and pathways associated with inner ear development and function, including Cochlin, NGFR, SOX11 and TGF-β signaling. These findings suggest that ZIKV and CMV infections cause congenital hearing loss through very different pathways; that is, by killing progenitor cells in the case of ZIKV infection, and via disruption of critical developmental pathways in the case of CMV infection. In addition to demonstrating differential hCMV and ZIKV pathogenesis mechanisms in OPCs, this study highlights the advantages of otic progenitor cell models for the study of congenital hearing loss induced by viral infection.
2024-01-18 | GSE234062 | GEO