What does the troponin complex do?
The cardiac troponin complex, composed of three regulatory proteins (cTnI, cTnT, TnC), functions as the critical regulator of cardiac muscle contraction and relaxation. Myofilament protein-protein interactions are regulated by post-translational modifications (PTMs) to the protein constituents of this complex.
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What does the troponin complex do?
The cardiac troponin complex, composed of three regulatory proteins (cTnI, cTnT, TnC), functions as the critical regulator of cardiac muscle contraction and relaxation. Myofilament protein-protein interactions are regulated by post-translational modifications (PTMs) to the protein constituents of this complex.
Where is the troponin complex located?
The troponin complex is a group of three protein subunits located on the thin filament of the contractile apparatus. These three subunits—troponin T, troponin I, and troponin C—different in genetic and protein structure, act together to regulate muscle contraction.
Does calcium bind to troponin I or troponin C?
The troponin complex is made up of three components8–10: the calcium binding subunit, troponin C (TnC); the inhibitory subunit, troponin I (TnI); and an elongated protein, troponin T (TnT), that binds both TnC and TnI and anchors the entire complex to tropomyosin.
Which is better troponin I or T?
Cardiac troponin I appears to be a more specific marker of risk of composite cardiovascular disease and coronary heart disease, whereas cardiac troponin T is more strongly associated with risk of non–cardiovascular disease death.
What is troponin tropomyosin complex?
Troponin is a component of thin filaments (along with actin and tropomyosin), and is the protein complex to which calcium binds to trigger the production of muscular force. Troponin itself has three subunits, TnC, TnI, and TnT, each playing a role in force regulation.
Why is it called cross-bridge?
At high magnification, small bridgelike structures can be seen on the thick filaments extending toward the thin filaments in the overlap region. They are called cross bridges and are believed to be responsible for the movement and force developed during contraction (for the…
What subunit of troponin binds to actin?
Troponin I (TnI), the inhibitory subunit, binds actin in the relaxed state, thereby preventing muscle contraction by inhibiting the ATPase activity of actomyosin. Troponin T (TnT) is involved in the attachment of the troponin complex to the thin filament, binding tropomyosin and actin.
Can dehydration cause elevated troponin?
Another interesting observation is in Rhabdomyolysis, a life threatening condition involving severe skeletal muscle breakdown due to trauma, overxertion, dehydration or toxic drug abuse[5] can also lead to falsely elevated cardiac Troponin measurements, and a cause for concern in the emergency department[6].
Can high blood pressure cause elevated troponin?
Background: High-sensitivity cardiac troponin T (hs-cTnT) is individually associated with incident hypertension (HTN) and cardiovascular disease (CVD) events. We hypothesize that the increases in hs-cTnT with increases in blood pressure will be related to higher incidence of CVD.
Is troponin I and T the same?