NMR derived model of GTPase effector domain (GED) self association: relevance to dynamin assembly

Chakraborty, Swagata ; Pratihar, Supriya ; Hosur, Ramakrishna V. (2010) NMR derived model of GTPase effector domain (GED) self association: relevance to dynamin assembly PLoS ONE, 7 (1). e30109. ISSN 1932-6203

PDF - Publisher Version

Official URL: http://www.plosone.org/article/info%3Adoi%2F10.137...

Related URL: http://dx.doi.org/10.1371/journal.pone.0030109


Self-association of dynamin to form spiral structures around lipidic vesicles during endocytosis is largely mediated by its 'coiled coil' GTPase Effector Domain (GED), which, in vitro, self-associates into huge helical assemblies. Residue-level structural characterizations of these assemblies and understanding the process of association have remained a challenge. It is also impossible to get folded monomers in the solution phase. In this context, we have developed here a strategy to probe the self-association of GED by first dissociating the assembly using Dimethyl Sulfoxide (DMSO) and then systematically monitoring the refolding into helix and concomitant re-association using NMR spectroscopy, as DMSO concentration is progressively reduced. The short segment, Arg109 - Met116, acts as the nucleation site for helix formation and self-association. Hydrophobic and complementary charge interactions on the surfaces drive self-association, as the helices elongate in both the directions resulting in an antiparallel stack. A small N-terminal segment remains floppy in the assembly. Following these and other published results on inter-domain interactions, we have proposed a plausible mode of dynamin self assembly.

Item Type:Article
Source:Copyright of this article belongs to Public Library of Science.
ID Code:80112
Deposited On:31 Jan 2012 04:21
Last Modified:18 May 2016 22:14

Repository Staff Only: item control page