Actin protein (chicken gizzard muscle, >99% pure)

Question 1: Do you have purified actin protein that is primarily composed of gamma actin?

Answer 1: The isotype composition of chicken gizzard smooth muscle actin ((Cat. #AS99) is approximately 80% g-smooth muscle and 20% b-cytoplasmic actin.

Question 2: How do I measure actin polymerization with the pyrene assay when there is no available pyrene conjugate for smooth muscle actin from chicken gizzard?

Answer 2: To examine the polymerization of unlabeled smooth muscle actin, please click here for a polymerization protocol that uses an excess of the unlabeled [smooth muscle] 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 smooth muscle actin 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.