Sequence similarity between stereocilin and otoancorin points to a unified mechanism for mechanotransduction in the mammalian inner ear.
BACKGROUND
Interaction between hair cells and acellular gels of the mammalian inner ear, the tectorial and otoconial membranes, is crucial for mechanoreception. Recently, otoancorin was suggested to be a mediator of gel attachment to nonsensory cells, but the molecular components of the interface between gels and sensory cells remain to be identified.


OBJECTIVE
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.


METHODS
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.


CONCLUSIONS
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.
Jovine
Luca
L
Brookdale Department of Molecular, Cell and Developmental Biology, Mount Sinai School of Medicine, New York, NY 10029-6574, USA. luca.jovine@mssm.edu
Park
Jong
J
Wassarman
Paul M
PM
D000595:Amino Acid Sequence; D000818:Animals; D058851:GPI-Linked Proteins; D006199:Hair Cells, Auditory, Inner / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins; D008322:Mammals / Q000235:genetics; D040542:Mechanotransduction, Cellular / Q000235:genetics*; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics; D008954:Models, Biological; D008969:Molecular Sequence Data; D010037:Otolithic Membrane / Q000737:chemistry; D011506:Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013680:Tectorial Membrane / Q000737:chemistry
D058851:GPI-Linked Proteins; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C456027:OTOA protein, human; C486746:Otoa protein, mouse; D011506:Proteins; C499079:STRC protein, human