ABSTRACT
This chapter summarizes the results of in vitro studies aimed at understanding how the dynein motor domain in the heavy chain drives dynein motility. It presents the results of structural studies together with those of biochemical and biophysical studies that addressed the mechanism of dynein-based motility, in particular focusing on how the functional subdomains in the dynein motor domain change their conformation and coordinate with other subdomains to drive dynein motility. The chapter focuses on the mechanism of the monomeric motor domain as dynein’s minimal motor unit. However, most dynein isoforms function as dimers or trimers of the motor domains, and coordinated actions of the multiple motor domains are critical for proper in vivo functions. Electron microscopy studies on axonemal and cytoplasmic dyneins have highlighted the importance of the linker, which connects the tail to the head domain. Kinetic parameters of the linker swing have been obtained by fluorescence resonance energy transfer measurements using a genetically engineered dynein motor domain.
