Characterization of the adenosinetriphosphatase and calsequestrin isolated from sarcoplasmic reticulum of normal and dystrophic chickens

Abstract

The Ca2+ + Mg2+-dependent ATPase (EC 3.6.1.3) and calsequestrin were isolated from the sarcoplasmic reticulum of normal and dystrophic chicken muscle. The ATPases, isolated from the 2 lines of chickens were identical in molecular weight, enzyme activity and in Ca2+ + Mg2+-dependence. Calsequestrins isolated from the 2 lines bound identical amounts of Ca. There were no differences in the Ca2+ transport functions of the SR membrane, isolated from the 2 lines of chickens. Morphological differences in dystrophic chicken SR, described by Sabbadini et al. apparently cannot be ascribed to qualitative differences in the ATPase or calsequestrin.