Calcium signaling in physiology and pathophysiology

Calcium ions are the most ubiquitous and pluripotent cellular signaling molecules that control a wide variety of cellular processes. The calcium signaling system is represented by a relatively limited number of highly conserved transporters and channels, which execute Ca²⁺ movements across biological membranes and by many thousands of Ca²⁺-sensitive effectors. Molecular cascades, responsible for the generation of calcium signals, are tightly controlled by Ca²⁺ ions themselves and by genetic factors, which tune the expression of different Ca²⁺-handling molecules according to adaptational requirements. Ca²⁺ ions determine normal physiological reactions and the development of many pathological processes.