Conformational Changes in the Foot Protein of the Sarcoplasmic Reticulum Assessed by Site-Directed Fluorescent Labeling

Ca 2+ release from sarcoplasmic reticulum during excitation-contraction coupling is likely to be mediated by conformational changes in the foot protein moiety of the triadic vesicles. As a preparative step toward the studies of dynamic conformational changes in the foot protein moiety, we have developed a new method that permits specific labeling of the foot protein moiety of the isolated membranes with a fluorophore