The Ca²⁺-signaling pathway

The Ca²⁺-signaling pathway involves the use of calcium ions (Ca²⁺) as messengers within cells. When a cell receives a signal, it triggers an increase in internal Ca²⁺ levels, often by releasing these ions from storage areas inside the cell or allowing them to enter from outside. The rise in Ca²⁺ activates various proteins and processes, leading to responses such as gene expression, muscle contraction, or secretion. Afterward, Ca²⁺ levels return to normal, resetting the system for future signals. This pathway is fundamental for coordinating many cellular functions and communication.