Three-dimensional structure of cytoplasmic dynein bound to microtubules

doi:10.1073/pnas.0710406105

Three-dimensional structure of cytoplasmic dynein bound to microtubules

*Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9039;
^‡Exploratory Research for Advanced Technology Office Actin Filament Dynamics Project and
^§RIKEN Harima Institute, Japan Scence and Technology Agency, Sayo, Hyogo, 679-5418, Japan;
^¶Division of Biological Science, Graduate School of Science, Nagoya University, Division of Biological Science, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan; and
^‖Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan

Communicated by Chikashi Toyoshima, University of Tokyo, Tokyo, Japan, November 1, 2007 (received for review July 5, 2007)

Abstract

Cytoplasmic dynein is a large, microtubule-dependent molecular motor (1.2 MDa). Although the structure of dynein by itself has been characterized, its conformation in complex with microtubules is still unknown. Here, we used cryoelectron microscopy (cryo-EM) to visualize the interaction between dynein and microtubules. Most dynein molecules in the nucleotide-free state are bound to the microtubule in a defined conformation and orientation. A 3D image reconstruction revealed that dynein's head domain, formed by a ring-like arrangement of AAA+ domains, is located ≈280 Å away from the center of the microtubule. The order of the AAA+ domains in the ring was determined by using recombinant markers. Furthermore, a 3D helical image reconstruction of microtubules with a dynein's microtubule binding domain [dynein stalk (DS)] revealed that the stalk extends perpendicular to the microtubule. By combining the 3D maps of the dynein-microtubule and DS-microtubule complexes, we present a model for how dynein in the nucleotide-free state binds to microtubules and discuss models for dynein's power stroke.

Footnotes

^††To whom correspondence should be addressed. E-mail: mkikkawa{at}em.biophys.kyoto-u.ac.jp
Author contributions: N.M., K.S., and M.K. designed research; N.M. performed research; N.M., A.N., T.K., and K.S. contributed new reagents/analytic tools; N.M. and A.N. analyzed data; and N.M. and M.K. wrote the paper.
↵ ^†Present address: Laboratory of Structural Biology, National Institute for Arthritis, Musculoskeletal, and Skin Diseases, National Institutes of Health, Bethesda, MD 20892.
↵**Present address: Graduate School of Science, Kyoto University, Oiwake, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502, Japan.
The authors declare no conflict of interest.
This article contains supporting information online at www.pnas.org/cgi/content/full/0710406105/DC1.