tropomyosin
(noun)
any of a family of muscle proteins that regulate the interaction of actin and myosin
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.