Definition:

Small calcium binding protein that plays important roles in several biological processes such as Ca(2+) homeostasis, chondrocyte biology and cardiomyocyte regulation. In response to an increase in intracellular Ca(2+) levels, binds calcium which triggers conformational changes. These changes allow interactions with specific target proteins and modulate their activity. Regulates a network in cardiomyocytes controlling sarcoplasmic reticulum Ca(2+) cycling and mitochondrial function through interaction with the ryanodine receptors RYR1 and RYR2, sarcoplasmic reticulum Ca(2+)-ATPase/ATP2A2 and mitochondrial F1-ATPase. Facilitates diastolic Ca(2+) dissociation and myofilament mechanics in order to improve relaxation during diastole.