Nucleotide switches in molecular motors: structural analysis of kinesins and myosins.

Recent breakthroughs in the structural biology of cytoskeletal motor proteins show that two distinct families of motors--kinesins and myosins - use a similar mechanism of conformational switching for converting small structural changes in their nucleotide-binding sites into larger movements to provide force generation and motion. This mechanism is found to be similar to that employed by G proteins, the well-known molecular switches that regulate protein-protein interactions in many biological systems.