Actin protein (bovine cardiac muscle, >99% pure)

Question 1: What is the isotype composition of the cardiac actin from bovine heart muscle?

Answer 1: Bovine cardiac actin ((Cat. #AD99) is composed of 84% a-cardiac and 16% a??˜-skeletal actin isoforms.

Question 2: How do I measure actin polymerization with the pyrene assay when there is no available pyrene conjugate for cardiac actin?

Answer 2: To examine the polymerization of unlabeled cardiac actin ((Cat. #AD99), please click here for a polymerization protocol that uses an excess of the unlabeled [cardiac] actin plus 10% of pyrene-labeled skeletal muscle actin. The pyrene muscle actin will not polymerize on its own at the concentration used in this assay, so the reaction is dependent on unlabeled cardiac actin ((Cat. #AD99) for F-actin formation. In this way, the pyrene-labeled muscle actin is taken up and polymerized to serve as a reporter for polymerization of the unlabeled actin that is present at a much greater concentration.