Molecular organization and force-generating mechanism of dynein.

Dynein, which is a minus-end-directed microtubule motor, is crucial to a range of cellular processes. The mass of its motor domain is about 10 times that of kinesin, the other microtubule motor. Its large size and the difficulty of expressing and purifying mutants have hampered progress in dynein research. Recently, however, electron microscopy, X-ray crystallography and single-molecule nanometry have shed light on several key unsolved questions concerning how the dynein molecule is organized, what conformational changes in the molecule accompany ATP hydrolysis, and whether two or three motor domains are coordinated in the movements of dynein. This minireview describes our current knowledge of the molecular organization and the force-generating mechanism of dynein, with emphasis on findings from electron microscopy and single-molecule nanometry.