Dynamics of the couple proteins in tip-linksduring hearing

Abstract

Discovery of mechanical transducers that help us to converttouch into nerve impulses earned Professor Ardem Patapoutianthe Nobel Prize in Physiology or Medicine 2021. Hearing is simi-larly a mechanotransduction process, where a protein-couple,jointly known as tip-links, serve as gating-springs and convey theinput mechanical force of varying intensities from sound-stimulito electrical signal. Importantly, tip-links maintain the integrityof their marriage under periodic tension from input sound. Withan overarching objective to decipher the force-responsive behav-iors of tip-link complexes and their alterations with aging, herewe probe the viscoelastic properties of the tip-links directly undermechanical stimuli at the single-molecule level. In this talk, Ishall present how tip-links form counterintuitive ‘catch-bonds’ toovercome the mechanical pulses from sound, and as gear-box,accelerate the lifetime of the complex while conveying force fortransduction. Further, tip-links serve as guardians to the non-re-generative hair-cells from the sudden impact of loud noise and atthe cost of their marriage. Tip-links dissociate, however, re-en-gage fast. Towards the end, I shall discuss how tip-link proteinsundergo phase separation on a cell membrane to accelerate there-formation of tip-links and cell-cell adhesion.