4uud
Human dynamin 1 K44A superconstricted polymer stabilized with GTPHuman dynamin 1 K44A superconstricted polymer stabilized with GTP
Structural highlights
FunctionDYN1_HUMAN Microtubule-associated force-producing protein involved in producing microtubule bundles and able to bind and hydrolyze GTP. Most probably involved in vesicular trafficking processes. Involved in receptor-mediated endocytosis. Publication Abstract from PubMedDynamin is a 100 kDa GTPase that organizes into helical assemblies at the base of nascent clathrin-coated vesicles. Formation of these oligomers stimulates the intrinsic GTPase activity of dynamin, which is necessary for efficient membrane fission during endocytosis. Recent evidence suggests that the transition state of dynamin's GTP hydrolysis reaction serves as a key determinant of productive fission. Here, we present the structure of a transition-state-defective dynamin mutant K44A trapped in a prefission state at 12.5 A resolution. This structure constricts to 3.7 nm, reaching the theoretical limit required for spontaneous membrane fission. Computational docking indicates that the ground-state conformation of the dynamin polymer is sufficient to achieve this superconstricted prefission state and reveals how a two-start helical symmetry promotes the most efficient packing of dynamin tetramers around the membrane neck. These data suggest a model for the assembly and regulation of the minimal dynamin fission machine. A dynamin mutant defines a superconstricted prefission state.,Sundborger AC, Fang S, Heymann JA, Ray P, Chappie JS, Hinshaw JE Cell Rep. 2014 Aug 7;8(3):734-42. doi: 10.1016/j.celrep.2014.06.054. Epub 2014, Jul 31. PMID:25088425[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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