Abstract
In addition to the well-known metabolic functions of NAD and NADP, it is rapidly emerging that these 2 pyridine nucleotides and their derivatives also play important roles in cell signaling. Surprisingly, a number of NAD(P) metabolizing enzymes and NAD(P) targets have been found on the outer surface of the plasma membrane and the presence of NAD has been confirmed in extracellular fluids. These findings have opened the door to a new field of research aimed at elucidating the contribution of extracellular pyridine nucleotides in physiological signaling pathways and pathological conditions.

Similar content being viewed by others
References
Berger F, Ramirez-Hernandez MH, Ziegler M. (2004) The new life of a centenarian: signaling functions of NAD(P). Trends Biochem. Sci. 29:111–8.
Thjötta T, Avery OT. (1921) Studies on bacterial nutrition: II. Growth accessory substances in the cultivation of hemophilic bacilli. J. Exp. Med. 34:97–114.
Lwoff A, Lwoff M. (1937) Studies on codehydrogenases. 1. Nature of growth factor ‘V’. Proc. Roy. Soc., London, series B. 122:352–9.
Zocchi E et al. (1999) Ligand-induced internalization of CD38 results in intracellular Ca2+ mobilization: role of NAD transport across cell membranes. Faseb. J. 13:273–83.
O’Reilly T, Niven DF. (2003) Levels of nicotinamide adenine dinucleotide in extracellular body fluids of pigs may be growth-limiting for Actinobacillus pleuropneumoniae and Haemophilus parasuis. Can. J. Vet. Res. 67:229–31.
Seman M, Adriouch S, Scheuplein F et al. (2003) NAD-induced T cell death: ADP-ribosylation of cell surface proteins by ART2 activates the cytolytic P2 /times/ 7 purinoceptor. Immunity. 19:571–82.
Smyth LM, Bobalova J, Mendoza MG, Lew C, Mutafova-Yambolieva VN. (2004) Release of beta-nicotinamide adenine dinucleotide upon stimulation of postganglionic nerve terminals in blood vessels and urinary bladder. J. Biol. Chem. 279:48893–903.
Bruzzone S, Guida L, Zocchi E, Franco L, De Flora A. (2001) Connexin 43 hemi channels mediate Ca2+-regulated transmembrane NAD+ fluxes in intact cells. FASEB. J. 15:10–2.
De Flora A, Zocchi E, Guida L, Franco L, Bruzzone S. (2004) Autocrine and paracrine calcium signaling by the CD38/NAD+/cyclic ADP-ribose system. Ann. N.Y. Acad. Sci. 1028:176–91.
Ziegler M, Niere M. (2004) NAD+ surfaces again. Biochem. J. 382:e5–6.
Aksoy P, White TA, Thompson M, Chini EN. (2006) Regulation of intracellular levels of NAD: a novel role for CD38. Biochem. Biophys. Res. Commun. 345:1386–92.
Young GS, Choleris E, Lund FE, Kirkland JB. (2006) Decreased cADPR and increased NAD+ in the Cd38-/-mouse. Biochem. Biophys. Res. Commun. 346:188–92.
Koch-Nolte F et al. (2006) ADP-ribosylation of membrane proteins: unveiling the secrets of a crucial regulatory mechanism in mammalian cells. Ann. Med. 38:188–99.
Aktories K, Just I. (2000) Bacterial Protein Toxins. Springer Verlag, Berlin.
Okazaki IJ, Moss J. (1998) Glycosylphosphatidylinositol-anchored and secretory isoforms of mono-ADP-ribosyltransferases. J. Biol. Chem. 273:23617–20.
Glowacki G et al. (2002) The family of toxin-related ecto-ADP-ribosyltransferases in humans and the mouse. Protein Sci. 11:1657–70.
Haag F, Koch-Nolte F, Kuhl M, Lorenzen S, Thiele HG. (1994) Premature stop codons inactivate the RT6 genes of the human and chimpanzee species. J. Mol. Biol. 243:537–46.
Bannas P et al. (2005) Activity and specificity of toxin-related mouse T cell ecto-ADP-ribosyltransferase ART2.2 depends on its association with lipid rafts. Blood. 105:3663–70.
Han MK, Cho YS, Kim YS, Yim CY, Kim UH. (2000) Interaction of two classes of ADP-ribose transfer reactions in immune signaling. J. Biol. Chem. 275:20799–805.
Nemoto E, Yu Y, Dennert G. (1996) Cell surface ADP-ribosyltransferase regulates lymphocyte function-associated molecule-1 (LFA-1) function in T cells. J. Immunol. 157:3341–9.
Krebs C et. al. (2005) CD38 controls ADP-ribosyltransferase-2-catalyzed ADP-ribosylation of T cell surface proteins. J. Immunol. 174: 3298–305.
Chen J et al. (2006) Targeted disruption of CD38 accelerates autoimmune diabetes in NOD/Lt mice by enhancing autoimmunity in an ART2-dependent fashion. J. Immunol. in press.
Sano Y et al. (2001) Immunocyte Ca2+ influx system mediated by LTRPC2. Science. 293:1327–30.
Moreschi I et al. (2006) Extracellular NAD+ is an agonist of the human P2Y11 purinergic receptor in human granulocytes. J. Biol. Chem. 281:31419–29.
Bruzzone S et al. (2006) Extracellular NAD+ regulates intracellular calcium levels and induces activation of human granulocytes. Biochem. J. 393:697–704.
Judkins CP et al. (2006) NADPH-induced contractions of mouse aorta do not involve NADPH oxidase: a role for P2X receptors. J. Pharmacol. Exp. Ther. 317:644–50.
Heidemann AC, Schipke CG, Kettenmann H. (2005) Extracellular application of nicotinic acid adenine dinucleotide phosphate induces Ca2+ signaling in astrocytes in situ. J. Biol. Chem. 280:35630–40.
Singaravelu K, Deitmer JW. (2006) Calcium mobilization by nicotinic acid adenine dinucleotide phosphate (NAADP) in rat astrocytes. Cell Calcium. 39:143–53.
De Flora A, Guida L, Franco L, Zocchi E. (1997) The CD38/Cyclic ADP-ribose system: A topological paradox. E. Int. J. Biochem. Cell Biol. 29:1149–66.
Billington RA et al. (2006) A transport mechanism for NAADP in a rat basophilic cell line. FASEB. J. 20:521–3.30.
Franco L et al. (2001) Paracrine roles of NAD+ and Cyclic ADP-ribose in increasing intracellular calcium and enhancing cell proliferation of 3T3 fibroblasts. J. Biol. Chem. 276:21642–8.
Lauwereys M et al. (1998) Potent enzyme inhibitors derived from dromedary heavy-chain antibodies. EMBO. J. 17:3512–20.
Goodrich SP et al. (2005) Production of calcium-mobilizing metabolites by a novel member of the ADP-ribosyl cyclase family expressed in Schistosoma mansoni. Biochemistry. 44:11082–97.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Billington, R.A., Bruzzone, S., De Flora, A. et al. Emerging Functions of Extracellular Pyridine Nucleotides. Mol Med 12, 324–327 (2006). https://doi.org/10.2119/2006-00075.Billington
Received:
Accepted:
Published:
Issue date:
DOI: https://doi.org/10.2119/2006-00075.Billington

