tropomyosin

Examples of tropomyosin in the following topics:

• Regulatory Proteins

  • Tropomyosin and troponin prevent myosin from binding to actin while the muscle is in a resting state.
  • The protein complex troponin binds to tropomyosin, helping to position it on the actin molecule.
  • Once the tropomyosin is removed, a cross-bridge can form between actin and myosin, triggering contraction.
  • Calcium then binds to troponin, causing the troponin to change shape and remove the tropomyosin from the binding sites.
  • Describe how calcium, tropomyosin, and the troponin complex regulate the binding of actin by myosin

• Control of Muscle Tension

  • As mentioned above, increasing the frequency of action potentials (the number of signals per second) can increase the force a bit more because the tropomyosin is flooded with calcium.

• Skeletal Muscle Fibers

  • Thin filaments are composed predominately of actin, tropomyosin, and troponin.