The contraction of skeletal and cardiac muscle (striated muscle) is enabled when calcium ions bind to troponin, which causes a conformational change and pulls the tropomyosin off the myosin-binding sites on the actin filaments. The uncovering of the binding sites allows the myosin heads to bind the actin, forming a cross-bridge. Once ATP hydrolysis occurs, the power stroke needed for a muscle contraction pulls the actin and myosin filaments closer to the M line, shortening the sarcomere. Troponin is a trimeric complex of three proteins (I, T, and C), each with a different function that allows troponin to perform its role relating to muscle contraction.
You may include any references to papers as in: the use of JSmol in Proteopedia [1] or to the article describing Jmol [2] to the rescue.
Function
Disease
Relevance
Structural highlights
This is a sample scene created with SAT to by Group, and another to make of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes.
