Tropomyosin and Profilin Cooperate to Promote Formin-Mediated Actin Nucleation and Drive Yeast Actin Cable Assembly.

ABSTRACT: Tropomyosins comprise a large family of actin-binding proteins with critical roles in diverse actin-based processes [1], but our understanding of how they mechanistically contribute to actin filament dynamics has been limited. We addressed this question in S. cerevisiae, where tropomyosins (Tpm1 and Tpm2), profilin (Pfy1), and formins (Bni1 and Bnr1) are required for the assembly of an array of actin cables that facilitate polarized vesicle delivery and daughter cell growth. Formins drive cable formation by promoting actin nucleation and by accelerating actin filament elongation together with profilin [2]. In contrast, how tropomyosins contribute mechanistically to cable formation has been unclear, but genetic studies demonstrate that Tpm1 plays a more important role than Tpm2 [3, 4]. Here

SUBMITTER: Alioto SL 

PROVIDER: S-EPMC5140752 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature