Probable ion channel required for the normal function of hair cells (By similarity). Component of the hair cell's mechanotransduction (MET) machinery. Involved in mechanosensitive responses of the hair cells (PubMed:25114259). Interacts (via N-terminus) with both isoforms CD1 and CD3 of PCDH15A (via cytoplasmic domain); this interaction is required for mechanotransduction of the hair cells and correct localization of PCDH15A in hair bundles of the hair cells. Localized to mature hair bundles of the hair cells. In adults, expression is restricted to the hair cells of inner ear and lateral line organ. Expressed at higher levels in the larval inner ear than in the lateral-line neuromasts. Expressed in the nascent hair cells of the developing ear as early as 1 day post fertilization (dpf), and expression in the inner ear continues throughout development. Expression is restricted to the upper hair cell layer of the neuroepithelium at 5 dpf. Belongs to the TMC family.