noun, plural: troponins
A regulatory protein that is a complex of three polypeptides (i.e. troponin c, troponin i, and troponin t). It has an affinity for calcium ions and is associated with tropomyosin. Together with tropomyosin, it regulates actin-myosin interactions in skeletal and cardiac muscle contraction.
Troponin is made up of three regulatory proteins:
- Troponin c – binds with calcium ions
- Troponin i– binds with actin in thin filament
- Troponin t – binds with tropomysin
Word origin: From tropomyosin. Coined by the Japanese researchers Setsuro Ebashi and Ayako Kodama in 1966.
See also: tropomyosin