Dynactin increases the processivity of the cytoplasmic dynein motor

Abstract

Cytoplasmic dynein supports long-range intracellular movements of cargo in vivo but does not appear to be a processive motor protein by itself. We show here that the dynein activator, dynactin, binds microtubules and increases the average length of cytoplasmic-dynein-driven movements without affecting the velocity or microtubule-stimulated ATPase kinetics of cytoplasmic dynein. Enhancement of microtubule binding and motility by dynactin are both inhibited by an antibody to dynactin’s microtubule-binding domain. These results indicate that dynactin acts as a processivity factor for cytoplasmic-dynein-based motility and provide the first evidence that cytoskeletal motor processivity can be affected by extrinsic factors.

Cite this article

King, S., Schroer, T. Dynactin increases the processivity of the cytoplasmic dynein motor. Nat Cell Biol 2, 20–24 (2000). https://doi.org/10.1038/71338

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