Ca²+-binding properties and regulatory roles of lobster troponin C sites II and IV.

Abstract

Invertebrate troponin C typically contains Ca²⁺-specific binding sites, sites II and IV, in the N- and C-terminal domains, respectively. To investigate the roles of these sites for Ca²⁺-dependent regulation of muscle contraction, we generated lobster troponin C mutants, and analyzed their Ca²⁺-binding properties and regulatory effects on actomyosin-tropomyosin Mg-ATPase activity. The results suggest that Ca²⁺ binding to site IV is responsible for regulation at relatively low Ca²⁺ concentrations, while site II has an essential role in full activation at higher Ca²⁺ concentrations.

DOI: 10.1016/j.febslet.2013.06.042

Cite this paper

@article{Tanaka2013CabindingPA, title={Ca²+-binding properties and regulatory roles of lobster troponin C sites II and IV.}, author={Hiroyuki Tanaka and Hiroki Takahashi and Takao Ojima}, journal={FEBS letters}, year={2013}, volume={587 16}, pages={2612-6} }