Provided herein are methods for identifying a compound that modulates a Ryanodine receptor (Ryr). Fluorescence resonance energy transfer between an FKBP bound to an RyR and fluorescent derivatives of RyR binding partners (e.g., calmodulin) or domain-peptide biosensors is used to provide a readout dependent on the RyR functional state. The methods permit measurement of RyR present in a permeabilized cell or in a purified membrane.
Methods to identify modulators of RyR calcium channels