Calmodulin

Calmodulin (CaM) is a small calcium-binding protein that acts as a key calcium sensor and regulator in cells. It has four calcium-binding sites and undergoes conformational changes upon binding Ca²⁺, allowing it to interact with and activate various target proteins, such as kinases, phosphatases, and ion channels. Calmodulin plays a critical role in regulating processes like metabolism, cell proliferation, muscle contraction, and learning and memory.