Author/Editor     Verkhratsky, Alexei; Parpura, Vladimir
Title     Calcium signalling and calcium channels
Type     članek
Vol. and No.     Letnik 739
Publication year     2014
Volume     str. 1-3
ISSN     1879-0712 - European journal of pharmacology
Language     eng
Abstract     Calcium as a divalent cation was selected early in evolution as a signaling molecule to be used by both prokaryotes and eukaryotes. Its low cytosolic concentration likely reflects the initial concentration of this ion in the primordial soup/ocean as unicellular organisms were formed. As the concentration of calcium in the ocean subsequently increased, so did the diversity of homeostatic molecules handling calcium. This includes the plasma membrane channels that allowed the calciumentry, as well as extrusion mechanisms, i.e., exchangers and pumps. Further diversification occurred with the evolution of intracellular organelles, in particular the endoplasmic reticulum and mitochondria, which also contain channels, exchanger(s) and pumps to handle the homeostasis of calciumions. Calcium signalling system, based around coordinated interactions of the above molecular entities,can be activated by the opening of voltage-gated channels, neurotransmitters, second messengers and/or mechanical stimulation, and as such is all-pervading pathway in physiology and pathophysiology of organisms.
Keywords     calcium
evolution
prokaryotes
eucaryotes
channels
transporters