Identification of the coated vesicle proteins that bind calmodulin.

S 93,000 and 52,P0 were labeled. Specificity was demonstrated by the dependence of _L labeling on Ca , and by its reduction in the presence of unlabeled calmodulin or ,, Stelazine. Urea-soluble components of coated vesicles and material isolated by Sepharose CL4B chromatography formed a 52,000 MW labeled complex. Subtracting an apparent molecular weight of calmodulin of 20,000 from the weights of the covalently labeled complexes, the coated vesicle proteins that bind calmodulin are 110,000, 73,000 Sand 32,000 MW. The 32,000 MW protein is thought to participate in the coat structure but the other two are most likely associated with the vesicle.