Calcium increases titin N2A binding to F-actin and regulated thin filaments.

ABSTRACT: Mutations in titin are responsible for many cardiac and muscle diseases, yet the underlying mechanisms remain largely unexplained. Numerous studies have established roles for titin in muscle function, and Ca²⁺-dependent interactions between titin and actin have been suggested to play a role in muscle contraction. The present study used co-sedimentation assays, dynamic force spectroscopy (DFS), and in vitro motility (IVM) assays to determine whether the N2A region of titin, overlooked in previous studies, interacts with actin in the presence of Ca²⁺. Co-sedimentation demonstrated that N2A - F-actin binding increases with increasing protein and Ca²⁺ concentration, DFS demonstrated increased rupture forces and decreased k_off in the presence of Ca

SUBMITTER: Dutta S 

PROVIDER: S-EPMC6167357 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature