The molecules that mediate sensory transduction in the mammalian inner ear

•The molecular mechanisms of sensory transduction in hair cells are more complex than depicted in cartoons based on biophysical models.•Tip-links are composed of cadherin-23 and protocadherin-15.•TMC1 and TMC2 function as components of sensory transduction channels in hair cells.•The molecules, mechanisms and functions of anomalous mechanotransduction are unknown.•Myosins contribute to slow adaptation in vestibular hair cells. The molecular mechanisms of fast adaptation are unknown.

Years of searching and researching have finally yielded a few leads in the quest to identify molecules required for mechanosensory transduction in the mammalian inner ear. Studies of human and mouse genetics have raised the profile of several molecules that are crucial for the function sensory hair cells. Follow up studies have begun to define the molecular function and biochemical interactions of several key proteins. These studies have exposed a sensory transduction apparatus that is more complex than originally envisioned and have reinvigorated the search for additional molecular components required for normal inner ear function.