Activation of muscle contraction has been a topic of interest for over 60 years, During this period researchers have used various approaches such as electron microscopy, X-ray diffraction and solution kinetics to understand the structural and molecular basis of cooperative activation of muscle contraction. Muscle contraction is a process which occurs because of the interaction of a globular protein, myosin, with the thin filament which consists of filamentous F -actin. However this interaction is regulated by the presence of tropomyosin and troponin on the thin filament, where tropomyosin spans across seven actin monomers and troponin (which is bound to tropomyosin and also interacts with actin) acts as a calcium switch. Tropomyosin is positioned such that it blocks myosin binding sites on actin. The binding of calcium to troponin causes a positional change in the adjacent tropomyosin molecule; as a result the tropomyosin moves away exposing myosin binding sites on the thin filament, facilitating muscle contraction. However, calcium is not the only regulator of thin filament activation, strong myosin-binding also plays a crucial role in activating thin filaments (Rosenfeld and Taylor, 1985).
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:635902 |
| Date | January 2014 |
| Creators | Desai, Rama A. |
| Publisher | University of Essex |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
Page generated in 0.0026 seconds