To generate Ih activation curves with minimal contamination, tail currents were measured at −74 mV, near the reversal potential for the potassium-selective inward rectifier, IK1. The tail current was sampled at the moment of the step to −74 mV and plotted against prepulse potential. Conductance was calculated by dividing the Ih tail current by the difference (30 mV) between the step potential (−74 mV) and the experimentally determined reversal potential (−44 mV, as measured from type II hair cells in the presence of 500 μm BaCl2, which blocked IK1). Type II vestibular hair cells had a maximum conductance of 4.4 ± 2.6 nS, a half-activation voltage (V1/2) of −99 ± 6 mV, and a slope factor (S) of 8.5 ± 1.9 mV (n = 41; Fig. 2C). Under our experimental conditions, the conductance of Ih was slightly larger than previously reported in mouse vestibular hair cells (Rüsch et al., 1998), perhaps due to differences in the age of the cells or rundown of Ih. Because Ih can be modulated by a ...
Link to Pubmed [PMID] - 25122888. J. Neurosci. 2014 Aug;34(33):10853-69. The hair cell ribbon synapses of the mammalian auditory and vestibular systems differ greatly in their anatomical organization and firing properties. Notably, vestibular Type I hair cells (VHC-I) are surrounded by a single calyx-type afferent terminal that receives input from several ribbons, whereas cochlear inner hair cells (IHCs) are contacted by several individual afferent boutons, each facing a single ribbon. The specificity of the presynaptic molecular mechanisms regulating transmitter release at these different sensory ribbon synapses is not well understood. Here, we found that exocytosis during voltage activation of Ca(2+) channels displayed higher Ca(2+) sensitivity, 10 mV more negative half-maximum activation, and a smaller dynamic range in VHC-I than in IHCs. VHC-I had a larger number of Ca(2+) channels per ribbon (158 vs 110 in IHCs), but their Ca(2+) current density was twofold smaller because of a smaller open ...
TY - JOUR. T1 - Molecular architecture of the chick vestibular hair bundle. AU - Shin, Jung Bum. AU - Krey, Jocelyn F.. AU - Hassan, Ahmed. AU - Metlagel, Zoltan. AU - Tauscher, Andrew N.. AU - Pagana, James M.. AU - Sherman, Nicholas E.. AU - Jeffery, Erin D.. AU - Spinelli, Kateri J.. AU - Zhao, Hongyu. AU - Wilmarth, Phillip A.. AU - Choi, Dongseok. AU - David, Larry L.. AU - Auer, Manfred. AU - Barr-Gillespie, Peter G.. PY - 2013/3/1. Y1 - 2013/3/1. N2 - Hair bundles of the inner ear have a specialized structure and protein composition that underlies their sensitivity to mechanical stimulation. Using mass spectrometry, we identified and quantified ,1,100 proteins, present from a few to 400,000 copies per stereocilium, from purified chick bundles; 336 of these were significantly enriched in bundles. Bundle proteins that we detected have been shown to regulate cytoskeleton structure and dynamics, energy metabolism, phospholipid synthesis and cell signaling. Three-dimensional imaging using ...
Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in the gene encoding transmembrane channel-like 1 (TMC1) cause hearing loss without vestibular dysfunction in both mice and humans, we investigated the contribution of Tmc1 and the closely related Tmc2 to mechanotransduction in mice. We found that Tmc1 and Tmc2 were expressed in mouse vestibular and cochlear hair cells and that GFP-tagged TMC proteins localized near stereocilia tips. Tmc2 expression was transient in early postnatal mouse cochlear hair cells but persisted in vestibular hair cells. While mice with a targeted deletion of Tmc1 (Tmc1Δ mice) were deaf and those with a deletion of Tmc2 (Tmc2Δ mice) were phenotypically normal, Tmc1ΔTmc2Δ mice had profound vestibular dysfunction, deafness, ...
Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in the gene encoding transmembrane channel-like 1 (TMC1) cause hearing loss without vestibular dysfunction in both mice and humans, we investigated the contribution of Tmc1 and the closely related Tmc2 to mechanotransduction in mice. We found that Tmc1 and Tmc2 were expressed in mouse vestibular and cochlear hair cells and that GFP-tagged TMC proteins localized near stereocilia tips. Tmc2 expression was transient in early postnatal mouse cochlear hair cells but persisted in vestibular hair cells. While mice with a targeted deletion of Tmc1 (Tmc1Δ mice) were deaf and those with a deletion of Tmc2 (Tmc2Δ mice) were phenotypically normal, Tmc1ΔTmc2Δ mice had profound vestibular dysfunction, deafness, ...
Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in the gene encoding transmembrane channel-like 1 (TMC1) cause hearing loss without vestibular dysfunction in both mice and humans, we investigated the contribution of Tmc1 and the closely related Tmc2 to mechanotransduction in mice. We found that Tmc1 and Tmc2 were expressed in mouse vestibular and cochlear hair cells and that GFP-tagged TMC proteins localized near stereocilia tips. Tmc2 expression was transient in early postnatal mouse cochlear hair cells but persisted in vestibular hair cells. While mice with a targeted deletion of Tmc1 (Tmc1Δ mice) were deaf and those with a deletion of Tmc2 (Tmc2Δ mice) were phenotypically normal, Tmc1ΔTmc2Δ mice had profound vestibular dysfunction, deafness, ...
Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in the gene encoding transmembrane channel-like 1 (TMC1) cause hearing loss without vestibular dysfunction in both mice and humans, we investigated the contribution of Tmc1 and the closely related Tmc2 to mechanotransduction in mice. We found that Tmc1 and Tmc2 were expressed in mouse vestibular and cochlear hair cells and that GFP-tagged TMC proteins localized near stereocilia tips. Tmc2 expression was transient in early postnatal mouse cochlear hair cells but persisted in vestibular hair cells. While mice with a targeted deletion of Tmc1 (Tmc1Δ mice) were deaf and those with a deletion of Tmc2 (Tmc2Δ mice) were phenotypically normal, Tmc1ΔTmc2Δ mice had profound vestibular dysfunction, deafness, ...
Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in the gene encoding transmembrane channel-like 1 (TMC1) cause hearing loss without vestibular dysfunction in both mice and humans, we investigated the contribution of Tmc1 and the closely related Tmc2 to mechanotransduction in mice. We found that Tmc1 and Tmc2 were expressed in mouse vestibular and cochlear hair cells and that GFP-tagged TMC proteins localized near stereocilia tips. Tmc2 expression was transient in early postnatal mouse cochlear hair cells but persisted in vestibular hair cells. While mice with a targeted deletion of Tmc1 (Tmc1Δ mice) were deaf and those with a deletion of Tmc2 (Tmc2Δ mice) were phenotypically normal, Tmc1ΔTmc2Δ mice had profound vestibular dysfunction, deafness, ...
A modifier variant can abrogate risk of a monogenic disorder. DFNM1 is a locus on chromosome 1 encoding a dominant suppressor of human DFNB26 recessive, profound deafness. Here, we report that DFNB26 is associated with a substitution (p.Gly116Glu) in the pleckstrin-homology-domain of GAB1, an essential scaffold in the MET/HGF pathway. A dominant substitution (p.Arg544Gln) of METTL13, encoding a predicted methyltransferase, is the DFNM1 suppressor of GAB1-associated deafness. In zebrafish, human METTL13 mRNA harboring the modifier allele rescues the GAB1 associated morphant phenotype. In mouse, GAB1 and METTL13 co-localize in auditory sensory neurons, and METTL13 co-immunoprecipitates with GAB1 and SPRY2, indicating at least a tripartite complex. Expression of MET-signaling genes in human lymphoblastoid cells of individuals homozygous for p.Gly116Glu GAB1 revealed dysregulation of HGF, MET, SHP2, and SPRY2, all of which have reported variants associated with deafness. However, SPRY2 was not ...
Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in the gene encoding transmembrane channel-like 1 (TMC1) cause hearing loss without vestibular dysfunction in both mice and humans, we investigated the contribution of Tmc1 and the closely related Tmc2 to mechanotransduction in mice. We found that Tmc1 and Tmc2 were expressed in mouse vestibular and cochlear hair cells and that GFP-tagged TMC proteins localized near stereocilia tips. Tmc2 expression was transient in early postnatal mouse cochlear hair cells but persisted in vestibular hair cells. While mice with a targeted deletion of Tmc1 (Tmc1Δ mice) were deaf and those with a deletion of Tmc2 (Tmc2Δ mice) were phenotypically normal, Tmc1ΔTmc2Δ mice had profound vestibular dysfunction, deafness, ...
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Recessive mutations at the mouse pirouette (pi) locus result in hearing loss and vestibular dysfunction due to neuroepithelial defects in the inner ear. Using a positional cloning strategy, we have identified mutations in the gene Grxcr1 (glutaredoxin cysteine-rich 1) in five independent allelic strains of pirouette mice. We also provide sequence data of GRXCR1 from humans with profound hearing loss suggesting that pirouette is a model for studying the mechanism of nonsyndromic deafness DFNB25. Grxcr1 encodes a 290 amino acid protein that contains a region of similarity to glutaredoxin proteins and a cysteine-rich region at its C terminus. Grxcr1 is expressed in sensory epithelia of the inner ear, and its encoded protein is localized along the length of stereocilia, the actin-filament-rich mechanosensory structures at the apical surface of auditory and vestibular hair cells. The precise architecture of hair cell stereocilia is essential for normal hearing. Loss of function of Grxcr1 in
Several studies have noted an association between age and dizziness.6-8 ,12 ,14 The US NHANES reported that age was significantly associated with vestibular dysfunction.6 GNT-HIS also reported that moderate-to-severe dizziness or vertigo increased with age and the prevalence reached 37% in the age group 60 years and older.14 Hannaford et al7 showed that problems of balance increased with age. Our study also showed that the prevalence of dizziness and vestibular dysfunction in the 60-69 years and more than 70 years age segments is significantly higher than for those in the 40-49 years age segment. In multivariable analysis, dizziness and objective vestibular dysfunction assessed by the modified Romberg test showed a significant association with age (tables 1 and 2). The increase in prevalence with age can be explained by changes associated with the ageing of the vestibular system such as reduction of vestibular hair cells, degeneration of the cupula and otolith, and the ascending vestibular ...
TY - JOUR. T1 - Requirement for the βI and βIV tubulin isotypes in mammalian cilia. AU - Jensen-Smith, Heather C.. AU - Ludueña, Richard F.. AU - Hallworth, Richard. PY - 2003/7/1. Y1 - 2003/7/1. N2 - [Nielsen et al., 2001: Curr Biol 11:529-533], based on studies in Drosophila, have proposed that β tubulin in axonemal microtubules must contain a specific acidic seven amino acid sequence in its carboxyl terminus. In mammals, the two βIV isotypes (βIVa and βIVb) contain that sequence. In order to test the application of this hypothesis to mammals, we have examined the expression of β tubulin isotypes in four different ciliated tissues (trachea, ependyma, uterine tube, and testis) using isotype-specific antibodies and indirect immunofluorescence. We find that βIV tubulin is present in all ciliated cell types examined, but so is β1 tubulin. Taken together with recent studies that show that β1 and βIV tubulin are both present in the cilia of vestibular hair cells, olfactory neurons, and ...
The appearance of vestibular sensory cells and their progressive development has been the subject of many ontogenetic studies. Because deteriorating hair cells are supposed to play a role in balance disorders
In fish, amphibians, and birds, regeneration of sensory hair cells through asymmetric cell divisions of supporting cells can contribute to recovery of hearing and balance after hair cell loss caused by trauma or toxicity (1, 2). Mammalian hair cells do not spontaneously regenerate, even though supporting cells in vestibular sensory epithelia retain a limited ability to divide (3, 4). Consequently, hair cell death in mammals often leads to permanent impairment of hearing and balance.. As the inner ear develops, hair cell progenitor cells exit from the cell cycle and, like neurons, terminally differentiate. Negative cell cycle regulators apparently maintain the postmitotic status of hair cells and contribute to their terminal differentiation. The cyclin-dependent kinase inhibitors p27Kip1 and p19Ink4d participate in cell cycle exit of hair cell progenitors and in hair cell apoptosis, respectively (5, 6). However, the key regulators of cell cycle exit and concomitant hair cell terminal ...
It acts by interfering with the signal transmission between vestibular apparatus of the inner ear and the vomiting centre of the hypothalamus by limiting the activity of the vestibular hair cells which send signals about movement.[11] The disparity of signal processing between inner ear motion receptors and the visual senses is abolished, so that the confusion of brain whether the individual is moving or standing is reduced. Vomiting in motion sickness could be a physiological compensatory mechanism of the brain to keep the individual from moving so that it can adjust to the signal perception, but the true evolutionary reason for this malady is currently unknown.[12] When prescribed for balance problems and vertigo, cinnarizine is typically taken two or three times daily depending on the amount of each dose and when used to treat motion sickness, the pill is taken at least two hours before travelling and then again every four hours during travel.[13] However, a recent 2012 study comparing the ...
We used electron tomography of frog saccular hair cells to reconstruct presynaptic ultrastructure at synapses specialized for sustained transmitter release. Synaptic vesicles at inhibited synapses were abundant in the cytoplasm and covered the synaptic body at high density. Continuous maximal stimul …
Mature mammals exhibit very limited capacity for regeneration of auditory hair cells, while all non-mammalian vertebrates examined can regenerate them. In an effort to find therapeutic targets for deafness and balance disorders, scientists have examined gene expression patterns in auditory tissues under different developmental and experimental conditions. Microarray technology has allowed the large-scale study of gene expression profiles (transcriptomics) at whole-genome levels, but since mRNA expression does not necessarily correlate with protein expression, other methods, such as microRNA analysis and proteomics, are needed to better understand the process of hair cell regeneration. These technologies and some of the results of them are discussed in this review. Although there is a considerable amount of variability found between studies owing to different species, tissues and treatments, there is some concordance between cellular pathways important for hair cell regeneration. Since gene expression
Postembryonic production of hair cells, the highly specialized receptors for hearing, balance and motion detection, occurs in a precisely controlled manner in select species, including avians. Notch1, Delta1 and Serrate1 mediate cell specification in several tissues and species. We examined expression of the chicken homologs of these genes in the normal and drug-damaged chick inner ear to determine if signaling through this pathway changes during hair cell regeneration. In untreated post-hatch chicks, Delta1 mRNA is abundant in a subpopulation of cells in the utricle, which undergoes continual postembryonic hair cell production, but it is absent from all cells in the basilar papilla, which is mitotically quiescent. By 3 days after drug-induced hair cell injury, Delta1 expression is highly upregulated in areas of cell proliferation in both the utricle and basilar papilla. Delta1 mRNA levels are elevated in progenitor cells during DNA synthesis and/or gap 2 phases of the cell cycle and expression ...
Gene Information The protein encoded by this gene is a member of the keratin gene family. As a type I hair keratin it is an acidic protein which heterodimerizes with type II keratins to form hair and nails. The type I hair keratins are clustered in a region of chromosome 17q12-q21 and have the same direction of transcription. [provided by RefSeq Jul 2008]. ...
orientation of the stereocilia within the sensory epithelium is determined by the STRIOLA, a curved dividing ridge that runs through the middle of the MACULA - in the UTRICLE, the kinocilia are oriented TOWARD the striola, and in the SACCULE they are oriented AWAY from ...
We first reported that PCDH15 is essential for hearing and balance in the mouse and specifically for normal development of hair bundles (Alagramam et al., 2001a, 2001b; Pawlowski et al., 2006; Kikkawa et al., 2008). More recently, we showed that an in-frame deletion of 47 amino acids in EC9 of PCDH15 (associated with the av6J allele of Pcdh15 in the mouse) does not prevent formation of tip links, although the av6J links are apparently not stable over time (Alagramam et al., 2011). Similarly, a missense mutation in EC7 of mouse CDH23 does not affect the formation of tip links, although they are progressively lost (Schwander et al., 2009). In contrast, Pcdh15noddy homozygotes show that a point mutation in EC1 of PCDH15 disrupts bundle integrity, much like the null allele Pcdh15av3J. The hair bundle arrangement at P3 in Pcdh15noddy homozygotes was severely disrupted and misoriented; the kinocilia were often abnormally positioned as well. PCDH15 I108N was expressed in the hair bundle in Pcdh15noddy ...
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Death of sensory hair cells in the inner ear results in two global health problems that millions of people around the world suffer: hearing loss and balance disorders. Hair cells convert sound vibrations and head movements into electrical signals that are conveyed to the brain, and as a result of aging, exposure to noise, modern drugs or genetic predisposition, hair cells die. In mammals, the great majority of hair cells are produced during embryogenesis, and hair cells that are lost after birth are not replaceable. However, in the last decades, researches have shown some model organisms that retain the ability to regenerate hair cells damaged after embryogenesis, such as Zebrafish and chicken, providing clues as to the cellular and molecular mechanisms that may block hair cell regeneration in mammals. This discovery initiated a search for methods to stimulate regeneration or replacement of hair cells in mammals, a search that, if fruitful, will revolutionize the treatment of hearing loss and ...
Wnt signaling is a highly conserved pathway crucial for development and homeostasis of multicellular organisms. Secreted Wnt ligands bind Frizzled receptors to regulate diverse processes such as axis patterning, cell division, and cell fate specification. They also serve to govern self-renewal of somatic stem cells in several adult tissues. The complexity of the pathway can be attributed to the myriad of Wnt and Frizzled combinations as well as its diverse context-dependent functions. In the developing mouse inner ear, Wnt signaling plays diverse roles, including specification of the otic placode and patterning of the otic vesicle. At later stages, its activity governs sensory hair cell specification, cell cycle regulation, and hair cell orientation. In regenerating sensory organs from non-mammalian species, Wnt signaling can also regulate the extent of proliferative hair cell regeneration. This review describes the current knowledge of the roles of Wnt signaling and Wnt-responsive cells in hair cell
Cochlear hair cells are mechanoreceptors of the auditory system and cannot spontaneously regenerate in adult mammals; thus hearing loss due to hair cell damage is permanent. In contrast, hair cells...
Synonyms for end organs in Free Thesaurus. Antonyms for end organs. 5 words related to end organ: organ, endplate, end-plate, motor end plate, osmoreceptor. What are synonyms for end organs?
Definition of utricle in the Definitions.net dictionary. Meaning of utricle. What does utricle mean? Information and translations of utricle in the most comprehensive dictionary definitions resource on the web.
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The report establishes a theoretical framework and computational procedures which lead to an experimental strategy for distinguishing between two alternative modes of operation of the vestibular statoreceptors: the question is whether individual kinocilia in the maculae sacculi and utriculi are innervated by single vestibular afferent fibers; or else, whether convergence of neural discharges originating from several kinocilia with different orientation of functional polarization occurs in vestibular afferent fibers. If the former condition prevails, it is possible to calculate the vector of maximal sensitivity of each kinocilium from the polar plot of nerve discharge rates, obtained at suitable head positions in the gravity field. The principle of the procedure consists in the matching of experimental data with a computer simulated model of sacculus and utriculus. (Author)(*MEDICAL EQUIPMENT
The Mammalian Phenotype (MP) Ontology is a community effort to provide standard terms for annotating phenotypic data. You can use this browser to view terms, definitions, and term relationships in a hierarchical display. Links to summary annotated phenotype data at MGI are provided in Term Detail reports.
Katie Kindt, Ph.D., Acting Chief Research Statement The section on Sensory Cell Development and Function investigates how discrete subcellular signals, such as Ca2+ influx and vesicle release, shape hair cell development, and how these signals are required for proper physiological function.
J:117235 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 Feb;236(2):525-33 ...
Dear members of Tinnitus Talk, As we are all hoping that a cure for (subjective) tinnitus will come in the near future, I created this thread to try...
The semicircular ducts provide sensory input for experiences of rotary movements. They are oriented along the pitch, roll, and yaw axes. Each canal is filled with a fluid called endolymph and contains motion sensors within the fluids. At the base of each canal, the bony region of the canal is enlarged which opens into the utricle and has a dilated sac at one end called the osseous ampullae. Within the ampulla is a mound of hair cells and supporting cells called crista ampullaris. These hair cells have many cytoplasmic projections on the apical surface called stereocilia which are embedded in a gelatinous structure called the cupula. As the head rotates the duct moves but the endolymph lags behind owing to inertia. This deflects the cupula and bends the stereocilia within. The bending of these stereocilia alters an electric signal that is transmitted to the brain. Within approximately 10 seconds of achieving constant motion, the endolymph catches up with the movement of the duct and the cupula is ...
The semicircular ducts provide sensory input for experiences of rotary movements. They are oriented along the pitch, roll, and yaw axes. Each canal is filled with a fluid called endolymph and contains motion sensors within the fluids. At the base of each canal, the bony region of the canal is enlarged which opens into the utricle and has a dilated sac at one end called the osseous ampullae. Within the ampulla is a mound of hair cells and supporting cells called crista ampullaris. These hair cells have many cytoplasmic projections on the apical surface called stereocilia which are embedded in a gelatinous structure called the cupula. As the head rotates the duct moves but the endolymph lags behind owing to inertia. This deflects the cupula and bends the stereocilia within. The bending of these stereocilia alters an electric signal that is transmitted to the brain. Within approximately 10 seconds of achieving constant motion, the endolymph catches up with the movement of the duct and the cupula is ...
Free Online Library: Generation of hair cells: a monumental breakthrough.( , Editorial) by Ear, Nose and Throat Journal; Health, general Hearing loss Care and treatment Causes of
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...   Cristae (singular crista) are the internal compartments formed by the inner membrane of a mitochondrion. They are studded with proteins,
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Inner ear hair cells. Coloured scanning electron micrograph (SEM) of sensory outer hair cells (stereocilia) from the organ of corti, in the cochlea of the inner ear. These cells are surrounded by a fluid called the endolymph. As sound enters the ear it causes waves to form in the endolymph, which in turn cause these hairs to move. The movement is converted into an electrical signal, which is passed to the brain. Each V-shaped arrangement of hairs lies on the top of a single cell. Magnification: x5,000 when printed 10cm tall. - Stock Image P434/0062
Inner ear hair cells. Coloured scanning electron micrograph (SEM) of sensory hair cells in the cochlea of the inner ear. The crescent-shaped arrangements of hairs across top are the stereocilia. Each crescent lies atop a single cell. Magnification: x1000 when printed at 10 centimetres wide. - Stock Image F004/3259
Coreys research focuses on understanding the cellular and molecular basis of hearing. A specialized cell of the inner ear, called a hair cell, converts the mechanical stimulus of a sound wave into an electrical stimulus that is sent to the brain. These hair cells have a bundle of hair-like protrusions emanating from the top surface of the cell. These hairs are connected by fine filaments that are stretched every time the hair bundle is deflected by a sound vibration. The filaments are, in turn, connected directly to proteins called ion channels that respond to the stretch by producing an electrical current across the membrane ...
Multifunctional actin-bundling protein. Plays a major role in regulating the organization, dimension, dynamics and signaling capacities of the actin filament-rich microvilli in the mechanosensory and chemosensory cells (PubMed:9763424). Required for the assembly and stabilization of the stereociliary parallel actin bundles. Plays a crucial role in the formation and maintenance of inner ear hair cell stereocilia. Involved in the elongation of actin in stereocilia. In extrastriolar hair cells, required for targeting MYO3B to stereocilia tips, and for regulation of stereocilia diameter and staircase formation (By similarity).
Deafness caused by the terminal loss of inner ear hair cells is one of the most common sensory diseases. However, nonmammalian animals (e.g., birds, amphibians, and fish) regenerate damaged hair cells. To understand better the reasons underpinning such disparities in regeneration among vertebrates, we set out to define at high resolution the changes in gene expression associated with the regeneration of hair cells in the zebrafish lateral line. We performed RNA-Seq analyses on regenerating support cells purified by FACS. The resulting expression data were subjected to pathway enrichment analyses, and the differentially expressed genes were validated in vivo via whole-mount in situ hybridizations. We discovered that cell cycle regulators are expressed hours before the activation of Wnt/β-catenin signaling following hair cell death. We propose that Wnt/β-catenin signaling is not involved in regulating the onset of proliferation but governs proliferation at later stages of regeneration. In ...
Keywords: Vestibular, type II locks cell, morphology, mammal, synapse, JAX:000654, JAX:000664, RGD: 737903, Abdominal_10013626, Abdominal_10015251, Abdominal_2282417, Abdominal_2068506, Abdominal_2068336, Abdominal_477329, Abdominal_177520, Abdominal_10175616, Abdominal_2113875, Abdominal_399431, Abdominal_2079751, Abdominal_2286684 Intro In mammals, five vestibular body organs INO-1001 in the internal hearing encode motions of the mind and therefore regulate look, body motions, and body alignment. The saccule and utricle possess a toned physical epithelium known as a macula, and they respond to linear mind speeding and mind tilt. The anterior, posterior, and horizontal ampullae possess a even more complexly formed physical epithelium known as a crista, and they identify mind rotation in a range of aeroplanes. Locks cells are the physical mechanoreceptors in these body organs. Directional deflections of lengthy microvilli (stereocilia) on the areas of locks cells travel actions possibilities in ...
Actin-bundling protein found in intestinal microvilli, hair cell stereocilia, and fibroblast filopodia. May play a role in the regulation of bone development.
Specialized mechanoreceptors, known as hair cells, detect and encode angular and linear components of head movements as well as the orientation of the head with respect to gravity
Fig. 2.2.01. Two ependymal cellsFig. 2.2.02. Ependymal cell with kinocilia, microvilliFig. 2.2.03. Ependymal cell with intercellular contact