what is the TRPA1 channel? what is tip link?? explain in-depth.
recent experiments revealed that ther eis a special type of cation channel, the TRPA1 channel, on the tips of the stereocilia. It is likely that TRPA1 channels are induced to open and close by the bending of the stereocilia, thereby generating changes in receptor potential.
each channel is connected by an elastic filament, called a tip link, to the wall of the adjacent cilium. When the cilia are straight, the tension on the tip link holds the channel to a partially opened state, allowing a small leak of K ions from the endolymph into the hair cell. Displacement of the cilia in one direction increases tension on the top link, increasing the inward K current. Displacement in the opposite direction relives tension on the tip link, thereby allowing the channel to close completely, preventing inward K flow.