Structural mapping of divergent regions in the type 1 ryanodine receptor using fluorescence resonance energy transfer.

ABSTRACT: Ryanodine receptors (RyRs) release Ca(2+) to initiate striated muscle contraction. Three highly divergent regions (DRs) in the RyR protein sequence (DR1, DR2, and DR3) may confer isoform-specific functional properties to the RyRs. We used cell-based fluorescence resonance energy transfer (FRET) measurements to localize these DRs to the cryoelectron microscopic (cryo-EM) map of the skeletal muscle RyR isoform (RyR1). FRET donors were targeted to RyR1 using five different FKBP12.6 variants labeled with Alexa Fluor 488. FRET was then measured to the FRET acceptors, Cy3NTA or Cy5NTA, targeted to decahistidine tags introduced within the DRs. DR2 and DR3 were localized to separate positions within the "clamp" region of the RyR1 cryo-EM map, which is presumed to interface with Cav1.1. DR1 was loc

SUBMITTER: Mahalingam M 

PROVIDER: S-EPMC4156536 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature