Membrane tethering by the atlastin GTPase depends on GTP hydrolysis but not on forming the cross-over configuration.

ABSTRACT: The membrane-anchored atlastin GTPase couples nucleotide hydrolysis to the catalysis of homotypic membrane fusion to form a branched endoplasmic reticulum network. Trans dimerization between atlastins anchored in opposing membranes, accompanied by a cross-over conformational change, is thought to draw the membranes together for fusion. Previous studies on the conformational coupling of atlastin to its GTP hydrolysis cycle have been carried out largely on atlastins lacking a membrane anchor. Consequently, whether fusion involves a discrete tethering step and, if so, the potential role of GTP hydrolysis and cross-over in tethering remain unknown. In this study, we used membrane-anchored atlastins in assays that separate tethering from fusion to dissect the requirements for each. We found tha

SUBMITTER: Saini SG 

PROVIDER: S-EPMC4244202 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature