Ca2+ signalling: a new route to NAADP.
NAADP (nicotinic acid-adenine dinucleotide phosphate) is a derivative of NADP (nicotinamide-adenine dinucleotide phosphate), which differs by the presence of a nicotinic acid instead of a nicotinamide moiety. This small structural difference makes NAADP one of the most powerful second messengers known, able to mobilize intracellular Ca2+ in a wide range of cellular models, ranging from invertebrates to mammals. Despite this, our understanding of NAADP homoeostasis, metabolism and physiological action is still limited. A new report by Vasudevan and colleagues in this issue of the Biochemical Journal provides important new data by describing a new synthetic activity in sperm cells which may turn out to represent the most physiologically relevant route to this second messenger.
Rutter
Guy A
GA
Department of Cell Biology, Division of Medicine, Sir Alexander Fleming Building, Imperial College, London, Exhibition Road, London SW7 2AZ, UK. g.rutter@imperial.ac.uk
Bellomo
Elisa A
EA
D000818:Animals; D020013:Calcium Signaling; D006801:Humans; D053858:Metabolic Networks and Pathways; D009249:NADP / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D015290:Second Messenger Systems
D009249:NADP; C024376:NAADP