Phosphorylated phospholamban stabilizes a compact conformation of the cardiac calcium-ATPase.

ABSTRACT: The sarcoendoplasmic reticulum calcium ATPase (SERCA) plays a key role in cardiac calcium handling and is considered a high-value target for the treatment of heart failure. SERCA undergoes conformational changes as it harnesses the chemical energy of ATP for active transport. X-ray crystallography has provided insight into SERCA structural substates, but it is not known how well these static snapshots describe in vivo conformational dynamics. The goals of this work were to quantify the direction and magnitude of SERCA motions as the pump performs work in live cardiac myocytes, and to identify structural determinants of SERCA regulation by phospholamban. We measured intramolecular fluorescence resonance energy transfer (FRET) between fluorescent proteins fused to SERCA cytoplasmic domains.

SUBMITTER: Pallikkuth S 

PROVIDER: S-EPMC3797577 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature