Affiliation:
1. Department of Chemistry Yale University New Haven CT USA
2. Departments of Molecular Cellular and Developmental Biology, of Molecular Biophysics and Biochemistry and of Cell Biology Yale University New Haven CT USA
Abstract
Members of the Wiskott–Aldrich Syndrome protein (WASp) family activate Arp2/3 complex (actin‐related proteins 2 and 3 complex) to form actin filament branches. The proline‐rich domain (PRD) of WASp contributes to branching nucleation, and the PRD of budding yeast Las17 binds actin filaments [Urbanek AN et al. (2013) Curr Biol 23, 196–203]. Biochemical assays showed the recombinant PRD of fission yeast Schizosaccharomyces pombe Wsp1p binds actin filaments with micromolar affinity. Recombinant PRDs of both Wsp1p and Las17p slowed the elongation of actin filaments by Mg‐ATP‐actin monomers by half and slowed the spontaneous polymerization of Mg‐ATP‐actin monomers modestly. The affinity of PRDs of WASp‐family proteins for actin filaments is high enough to contribute to the reported stimulation of actin filament branching by Arp2/3 complex.
Funder
National Institutes of Health
Subject
Cell Biology,Genetics,Molecular Biology,Biochemistry,Structural Biology,Biophysics