Actin-binding domain of Rng2 sparsely bound on F-actin strongly inhibits actin movement on myosin II.

ABSTRACT: We report a case in which sub-stoichiometric binding of an actin-binding protein has profound structural and functional consequences, providing an insight into the fundamental properties of actin regulation. Rng2 is an IQGAP contained in contractile rings in the fission yeast Schizosaccharomyces pombe Here, we used high-speed atomic force microscopy and electron microscopy and found that sub-stoichiometric binding of the calponin-homology actin-binding domain of Rng2 (Rng2CHD) induces global structural changes in skeletal muscle actin filaments, including shortening of the filament helical pitch. Sub-stoichiometric binding of Rng2CHD also reduced the affinity between actin filaments and muscle myosin II carrying ADP and strongly inhibited the motility of actin filaments on myosin II

SUBMITTER: Hayakawa Y 

PROVIDER: S-EPMC9610768 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature