Identification of residues within tropomodulin-1 responsible for its localization at the pointed ends of the actin filaments in cardiac myocytes.

ABSTRACT: Tropomodulin is a tropomyosin-dependent actin filament capping protein involved in the structural formation of thin filaments and in the regulation of their lengths through its localization at the pointed ends of actin filaments. The disordered N-terminal domain of tropomodulin contains three functional sites: two tropomyosin-binding and one tropomyosin-dependent actin-capping sites. The C-terminal half of tropomodulin consists of one compact domain containing a tropomyosin-independent actin-capping site. Here we determined the structural properties of tropomodulin-1 that affect its roles in cardiomyocytes. To explore the significance of individual tropomyosin-binding sites, GFP-tropomodulin-1 with single mutations that destroy each tropomyosin-binding site was expressed in cardiomyocytes.

SUBMITTER: Tsukada T 

PROVIDER: S-EPMC3023515 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature