Isolation of troponin like complex from bovine brain cortex

A troponin-like complex has been isolated from bovine brain cortex. This troponin-like complex, with brain tropomyosin, confers Ca²⁺ sensitivity to the actin-activated myosin adenosinetriphosphatase (ATP phosphohydrolase, EC 3.6.1.3). That is, the Mg²⁺-stimulated ATPase activity generated by the interaction of purified muscle actin with muscle myosin is inhibited in the absence of Ca²⁺ but not in the presence of Ca²⁺ as a result of the addition of both brain tropomyosin and troponin-like complex. The troponin-like complex contains 3 components, one of which is similar in molecular weight to the troponin T of skeletal actomyosin.