troponin

American  

[troh-puh-nin, trop-uh-] / ˈtroʊ pə nɪn, ˈtrɒp ə- /

noun

Biochemistry.

1. a protein of muscle tissue that binds calcium ions and is involved in contraction.

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troponin Scientific  

/ trō′pə-nĭn,trŏp′ə- /

1. One of the proteins that make up the thin filaments of muscle tissue and that regulate muscle contraction and relaxation. Troponin occurs in three forms bound together in a complex. One of the three forms is a receptor of calcium ions that induces structural changes that allow the actin in the thin filaments to interact with myosin, causing contraction.

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Etymology

Origin of troponin

1965–70; tropo(myosin) ( see tropo-, myosin) + -n- (of uncertain origin) + -in ²

Example Sentences

To determine whether these cytokines directly harm the heart, the team vaccinated young male mice and observed increased cardiac troponin levels, indicating heart muscle injury.

From Science Daily • Dec. 27, 2025

"My troponin levels, which is a heart attack marker, were extremely high."

From BBC • Feb. 13, 2025

The thin filament consists of F-actin, troponin, tropomyosin, and nebulin.

From Science Daily • Nov. 1, 2023

None met the criteria for myocarditis but 40 had high levels of troponin, a molecule that can indicate damage to the heart muscle.

From Science Magazine • Oct. 17, 2022

Myosin binding sites are covered by tropomyosin to which the troponin complex is attached.

From Textbooks • Jun. 9, 2022