RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are. ; Abstract 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. Hypothesis 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. Testing 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. Implications 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. ; Published version