A decrease in NAMPT activity impairs basal PARP-1 activity in cytidine deaminase deficient-cells, independently of NAD

• Published in: Scientific reports Vol. 10; no. 1; p. 13907
• Main Authors: Silveira, Sandra Cunha, Buhagiar-Labarchède, Géraldine, Onclercq-Delic, Rosine, Gemble, Simon, Bou Samra, Elias, Mameri, Hamza, Duchambon, Patricia, Machon, Christelle, Guitton, Jérôme, Amor-Guéret, Mounira
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 17.08.2020; Nature Publishing Group; Nature Portfolio
• Subjects: 631/337; 631/67; 631/80; Anaphase; Biochemistry, Molecular Biology; Biosynthesis; Cancer; Cellular Biology; Cytidine deaminase; Cytidine Deaminase - deficiency; Cytidine Deaminase - metabolism; Cytokines - antagonists & inhibitors; Cytokines - genetics; Cytokines - metabolism; Enzymes; Genes; Genomes; HeLa Cells; Humanities and Social Sciences; Humans; Life Sciences; Molecular biology; multidisciplinary; Mutants; Mutation - genetics; NAD; NAD - metabolism; Niacinamide - metabolism; Nicotinamide phosphoribosyltransferase; Nicotinamide Phosphoribosyltransferase - antagonists & inhibitors; Nicotinamide Phosphoribosyltransferase - genetics; Nicotinamide Phosphoribosyltransferase - metabolism; Phosphoribosyltransferase; Poly (ADP-Ribose) Polymerase-1 - metabolism; Poly(ADP-ribose); Poly(ADP-ribose) polymerase; Poly(ADP-ribose) Polymerase 1; Proteins; Ribose; Science; Science (multidisciplinary)
• DOI: 10.1038/s41598-020-70874-6
• ISSN: 2045-2322

Cytidine deaminase (CDA) deficiency causes pyrimidine pool disequilibrium. We previously reported that the excess cellular dC and dCTP resulting from CDA deficiency jeopardizes genome stability, decreasing basal poly(ADP-ribose) polymerase 1 (PARP-1) activity and increasing ultrafine anaphase bridge (UFB) formation. Here, we investigated the mechanism underlying the decrease in PARP-1 activity in CDA-deficient cells. PARP-1 activity is dependent on intracellular NAD + concentration. We therefore hypothesized that defects of the NAD + salvage pathway might result in decreases in PARP-1 activity. We found that the inhibition or depletion of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD + salvage biosynthesis pathway, mimicked CDA deficiency, resulting in a decrease in basal PARP-1 activity, regardless of NAD + levels. Furthermore, the expression of exogenous wild-type NAMPT fully restored basal PARP-1 activity and prevented the increase in UFB frequency in CDA-deficient cells. No such effect was observed with the catalytic mutant. Our findings demonstrate that (1) the inhibition of NAMPT activity in CDA-proficient cells lowers basal PARP-1 activity, and (2) the expression of exogenous wild-type NAMPT, but not of the catalytic mutant, fully restores basal PARP-1 activity in CDA-deficient cells; these results strongly suggest that basal PARP-1 activity in CDA-deficient cells decreases due to a reduction of NAMPT activity.