The Dynein Catch Bond: Implications for cooperative transport

Intracellular bidirectional transport of cargo on microtubule filaments is achieved by the collective action of oppositely directed dynein and kinesin motors. Recent experiments have demonstrated that unline kinesin, dynein motor exhibits catch bonding behaviour, in which the unbinding rate of a single dynein decreases with increasing force, for a certain range of force. Motivated by these experiments, we propose a phenomenological model for catch bonding in dynein. We study the implications of the dynein catch bond for unidirectional and bidirectional cargo transport. We show that the functional divergence of the two motor species manifests itself as an internal regulatory mechanism, and can lead to codependent transport behavior in biologically relevant regimes.

Reference: Dynein catch bond as a mediator of codependent bidirectional cellular transport, Puri et. al. Phys. Rev. Research, 1, 023019 (2019)