ABSTRACT
This chapter focuses on cytoplasmic dynein force regulation, which allows the one motor protein to contribute to very fast, low-load transport functions, as well as much slower very high-load functions. It reviews basic mechanisms of dynein force production, as well as emerging mechanisms for dynein force regulation. Cytoplasmic dynein is particularly interesting for its extensive array of regulatory factors and mechanism of action. Cytoplasmic dynein is required for microtubule minus-end directed transport of diverse cellular cargoes ranging from macromolecules and membranous organelles to larger structures, such as nuclei. Cytoplasmic dynein force production has been monitored by use of laser trapping both in vitro and in vivo. In vivo measurements of dynein stall force have been made using laser trapping of lipid droplets or latex bead-containing phagosomes. In vivo studies have served to provide a check on the in vitro data.
