X-ray scattering study of actin polymerization nuclei assembled by tandem W domains.

ABSTRACT: The initiation of actin polymerization in cells requires actin filament nucleators. With the exception of formins, known filament nucleators use the Wiskott-Aldrich syndrome protein (WASP) homology 2 (WH2 or W) domain for interaction with actin. A common architecture, found in Spire, Cobl, VopL, and VopF, consists of tandem W domains that tie together three to four actin monomers to form a polymerization nucleus. Uncontrollable polymerization has prevented the structural investigation of such nuclei. We have engineered stable nuclei consisting of an actin dimer and a trimer stabilized by tandem W domain hybrid constructs and studied their structures in solution by x-ray scattering. We show that Spire-like tandem W domains stabilize a polymerization nucleus by lining up actin subunits along

SUBMITTER: Rebowski G 

PROVIDER: S-EPMC2504828 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature