Multiplicity of Ca2+ Messengers and Ca2+ Stores: A Perspective from Cyclic ADP-Ribose and NAADP
Hon Cheung Lee
Pages 227-237 (11)
It is generally believed that multiple Ca2+ stores are present in cells, a notion that has now been made substantive by the discovery of multiple Ca2+ mobilizing messengers. Cyclic ADP-ribose (cADPR) and nicotinic acid dinucleotide phosphate (NAADP) are two such messengers that are derived from NAD and NADP, respectively. A wide variety of cells, from plants to mammals, including human, have been shown to be responsive to these two novel Ca2+ messengers. Not only are their structures and mechanisms of action different, their targeted Ca2+ stores are also distinct and separable. This article explores the implications of the multiplicity of Ca2+ stores in cellular signaling. Special emphasis will be put on the recent progress in the understanding of the physiological functions of NAADP.
cyclic adp-ribose (cadpr), naadp, adp-ribosyl cyclase, cd38, mobilization
University of Minnesota,Department of Pharmacology. Minneapolis, MN 55455, USA.