Mechano-Sensitive Interaction between Talin and Full-Length Vinculin

Abstract

Interaction between talin and vinculin plays a critical role in stabilizing the focal adhesions (FAs) and regulates cell motility. In previous study, we showed that force applied to talin rod domains R1-R3 is necessary to expose the vinculin binding site, which drastically promotes the binding of the vinculin head domain. In this work, using magnetic tweezers single-molecule manipulation, we show that full-length vinculin also binds to mechanically unfolded talin R1-R3. It indicates that binding to mechanically unfolded talin R1-R3 results in dissociation of the vinculin tail domain from the head, implying release of the auto-inhibition conformation of full-length vinculin. Together, these results suggest that the force-dependent interaction between talin and vinculin likely plays a crucial role in vinculin activation in vivo.