The elusive mechanotransduction machinery of hair cells

•The mechanotransduction channel in hair cells consists of several subunits.•TMC1, TMC2, LHFPL5 and TMIE are candidate channel subunits.•Classical models of adaptation might not apply to cochlear hair cells.•Mechanotransduction might have a role in hair bundle morphogenesis.

Hair cells in the mammalian cochlea are specialized sensory cells that convert mechanical signals evoked by sound waves into electrochemical signals. Several integral membrane proteins have recently been identified that are closely linked to the mechanotransduction process. Efforts are under way to determine the extent to which they are subunits of the long thought-after mechanotransduction channel. Recent findings also suggest that mechanotransduction may have a role in fine tuning the length of the stereocilia and thus in the regulation of morphological features of hair cells that are inherently linked to the mechanotransduction process.