PMID: 20428113 , Related PDB ids: 1JWY, 2AKA, 2B92, 2GJ8, 2X2E, 2X2F

Authors:

Chappie JS, Acharya S, Leonard M, Schmid SL, Dyda F

Title:

G domain dimerization controls dynamin's assembly-stimulated GTPase activity.

Journal:

Nature. 2010 May 27;465(7297):435-40. Epub 2010 Apr 28.

Abstract:

Dynamin is an atypical GTPase that catalyses membrane fission during clathrin-mediated endocytosis. The mechanisms of dynamin's basal and assembly-stimulated GTP hydrolysis are unknown, though both are indirectly influenced by the GTPase effector domain (GED). Here we present the 2.0 A resolution crystal structure of a human dynamin 1-derived minimal GTPase-GED fusion protein, which was dimeric in the presence of the transition state mimic GDP.AlF(4)(-).The structure reveals dynamin's catalytic machinery and explains how assembly-stimulated GTP hydrolysis is achieved through G domain dimerization. A sodium ion present in the active site suggests that dynamin uses a cation to compensate for the developing negative charge in the transition state in the absence of an arginine finger. Structural comparison to the rat dynamin G domain reveals key conformational changes that promote G domain dimerization and stimulated hydrolysis. The structure of the GTPase-GED fusion protein dimer provides insight into the mechanisms underlying dynamin-catalysed membrane fission.