%0 Journal Article
%T Sequence similarity between stereocilin and otoancorin points to a unified mechanism for mechanotransduction in the mammalian inner ear
%A Luca Jovine
%A Jong Park
%A Paul M Wassarman
%J BMC Cell Biology
%D 2002
%I BioMed Central
%R 10.1186/1471-2121-3-28
%X We report that the inner ear protein stereocilin is related in sequence to otoancorin and, based on its localisation and predicted GPI-anchoring, may mediate attachment of the tectorial and otoconial membranes to sensory hair bundles.It is expected that antibodies directed against stereocilin would specifically label sites of contact between sensory hair cells and tectorial/otoconial membranes of the inner ear.Our findings support a unified molecular mechanism for mechanotransduction, with stereocilin and otoancorin defining a new protein family responsible for the attachment of acellular gels to both sensory and nonsensory cells of the inner ear.The cochlea and the vestibule, respectively, are responsible for hearing and balance in the mammalian inner ear. The tectorial membrane, an acellular gel, covers the surface of the organ of Corti within the cochlea. Similarly, otoconial and cupula membranes overlie sensory regions of the five organs constituting the vestibule. Sound-induced motion of the basilar membrane in the cochlea or head motion in the vestibule generates shear between the acellular gels and the apical surface of the sensory epithelia; the latter consist of both hair (sensory) and supporting (nonsensory) cells. Deflection of stereocilia bundles on sensory hair cells causes membrane potential alterations that transduce mechanical information into electrical signals [1-3]. Mutations in genes encoding protein components of the acellular gels result in hearing and balance defects, highlighting the importance of these structures in mechanotransduction [2-10]. Therefore, there is considerable interest in identifying molecules that are responsible for attachment of the gels to the sensory epithelia.Recently, two new genes specifically expressed in the human inner ear were described. STRC, a chromosome 15q15 gene mutated in families affected by non-syndromic deafness at the DFNB16 locus, was predicted to encode a polypeptide of 1778 amino acids of unknown func
%U http://www.biomedcentral.com/1471-2121/3/28