1. Academic Validation
  2. Activation of cytoplasmic dynein motility by dynactin-cargo adapter complexes

Activation of cytoplasmic dynein motility by dynactin-cargo adapter complexes

  • Science. 2014 Jul 18;345(6194):337-41. doi: 10.1126/science.1254198.
Richard J McKenney 1 Walter Huynh 1 Marvin E Tanenbaum 1 Gira Bhabha 1 Ronald D Vale 2
Affiliations

Affiliations

  • 1 Department of Cellular and Molecular Pharmacology and the Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA.
  • 2 Department of Cellular and Molecular Pharmacology and the Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA. vale@ucsf.edu.
Abstract

Cytoplasmic dynein is a molecular motor that transports a large variety of cargoes (e.g., organelles, messenger RNAs, and viruses) along microtubules over long intracellular distances. The dynactin protein complex is important for dynein activity in vivo, but its precise role has been unclear. Here, we found that purified mammalian dynein did not move processively on microtubules in vitro. However, when dynein formed a complex with dynactin and one of four different cargo-specific adapter proteins, the motor became ultraprocessive, moving for distances similar to those of native cargoes in living cells. Thus, we propose that dynein is largely inactive in the cytoplasm and that a variety of adapter proteins activate processive motility by linking dynactin to dynein only when the motor is bound to its proper cargo.

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