Recoverin, a novel calcium-binding protein from vertebrate photoreceptors

Photoreceptor guanylyl cyclase activity is modulated by an endogenous calcium-binding protein called recoverin. A modified isolation procedure for recoverin using gel-filtration chromatography instead of a heat denaturation step is presented. The elution volume of recoverin corresponds to a monomer. Recoverin exhibits a calcium-dependent mobility shift in a native gel electrophoresis. Isoelectric focusing revealed a pI of 5.25. No subspecies of recoverin were detected.