Module 10: Figure tip link
Hair cell tip links and mechanoelectrical transduction.
A gating spring hypothesis proposes that the minute displacements of the stereocilia induced by sound are converted into an electrical signal by a linear array of molecules that act to open the TRPA1 channels. The resting condition is shown in A, where the ankyrin spring maintains a small tension on the channel to allow some Ca2+ to enter to create a small microdomain of Ca2+ (shown in red). During deformation, the lower stereocilium uses the tip link to pull the channel open to create a large inward current carried by K+ and Ca2+. The latter forms a much larger microdomain that can be visualized in line scan recordings (Module 10: Figure stereocilia Ca2+ signals).