Stac proteins associate with the critical domain for excitation-contraction coupling in the II-III loop of Ca_V1.1.

ABSTRACT: In skeletal muscle, residues 720-764/5 within the Ca_V1.1 II-III loop form a critical domain that plays an essential role in transmitting the excitation-contraction (EC) coupling Ca²⁺ release signal to the type 1 ryanodine receptor (RyR1) in the sarcoplasmic reticulum. However, the identities of proteins that interact with the loop and its critical domain and the mechanism by which the II-III loop regulates RyR1 gating remain unknown. Recent work has shown that EC coupling in skeletal muscle of fish and mice depends on the presence of Stac3, an adaptor protein that is highly expressed only in skeletal muscle. Here, by using colocalization as an indicator of molecular interactions, we show that Stac3, as well as Stac1 and Stac2 (predominantly neuronal Stac isoforms), in

SUBMITTER: Polster A 

PROVIDER: S-EPMC5881444 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature