Three-dimensional structure of cytoplasmic dynein bound to microtubules.
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 approximately 280 A 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.
Mizuno
Naoko
N
Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9039, USA.
Narita
Akihiro
A
Kon
Takahide
T
Sutoh
Kazuo
K
Kikkawa
Masahide
M
D000255:Adenosine Triphosphate / Q000737:chemistry; D000818:Animals; D020285:Cryoelectron Microscopy; D003593:Cytoplasm / Q000378:metabolism*; D004023:Dictyostelium / Q000378:metabolism*; D004398:Dyneins / Q000737:chemistry*; D021621:Imaging, Three-Dimensional; D008870:Microtubules / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D008958:Models, Molecular; D008968:Molecular Conformation; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry
D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D004398:Dyneins