Troponin is a protein complex found in muscle tissue, particularly in cardiac and skeletal muscles. It plays a crucial role in muscle contraction by regulating the interaction between actin and myosin, the proteins responsible for muscle movement. When muscles are stimulated to contract, troponin changes shape, allowing these proteins to interact and generate force. In medical settings, measuring troponin levels in the blood is important for diagnosing heart attacks and other heart-related conditions. Elevated troponin levels indicate damage to the heart muscle, as troponin is released into the bloodstream when the heart is injured.