Tropomyosin is an actin-binding protein that regulates actin mechanics. It is important amongst other for muscle contraction. Tropomyosin, along with the troponin complex, associate with actin in muscle fibers and regulate muscle contraction by regulating the binding of myosin. In resting muscle, tropomyosin overlays the myosin binding sites on actin and is "locked" down in this position by troponin T (tropomyosin binding troponin) and troponin I (inhibitory troponin). Upon release of calcium f… (More on Tropomyosin)