Calcium signalling - an overview

Calcium (Ca2+) is an almost universal intracellular messenger controlling a diverse range of cellular processes, such as gene transcription (see Mellstrom and Naranjo, this issue), muscle contraction and cell proliferation. The ability of a simple ion such as Ca2+ to play a pivotal role in cell biology results from the facility that cells have to Ca2+ signals in the dimensions of space, time and shape Ca2+ signals. To generate the variety of observed Ca2+ signals, different cell types employ components selected from a Ca2+ signalling 'toolkit', which comprizes an array of signalling, homeostatic and sensory mechanisms. By mixing and marching components from the toolkit, cells can obtain Ca2+ signals that suit their physiology.