The NAD Biosynthesis Pathway Mediated by Nicotinamide Phosphoribosyltransferase Regulates Sir2 Activity in Mammalian Cells*

By Javier R. Revollo, Andrew A. Grimm, S. Imai. Journal of Biological Chemistry, 2004

990 citations recorded by the source corpus.

Recent studies have revealed new roles for NAD and its derivatives in transcriptional regulation. The evolutionarily conserved Sir2 protein family requires NAD for its deacetylase activity and regulates a variety of biological processes, such as stress response, differentiation, metabolism, and aging. Despite its absolute requirement for NAD, the regulation of Sir2 function by NAD biosynthesis pathways is poorly understood in mammals. In this study, we determined the kinetics of the NAD biosynthesis mediated by nicotinamide phosphoribosyltransferase (Nampt) and nicotinamide/nicotinic acid mononucleotide adenylyltransferase (Nmnat), and we examined its effects on the transcriptional regulatory function of the mouse Sir2 ortholog, Sir2α, in mouse fibroblasts. We found that Nampt was the ratelimiting component in this mammalian NAD biosynthesis pathway. Increased dosage of Nampt, but not Nmnat, increased the total cellular NAD level and enhanced the transcriptional regulatory activity of the catalytic domain of Sir2α recruited onto a reporter gene in mouse fibroblasts. Gene expression profiling with oligonucleotide microarrays also demonstrated a significant correlation between the expression profiles of Nampt- and Sir2α-overexpressing cells. These findings suggest that NAD biosynthesis mediated by Nampt regulates the function of Sir2α and thereby plays an important role in controlling various biological events in mammals.

Subfields: Epidemiology, Geriatrics and Gerontology, Oncology

View Paper: https://www.semanticscholar.org/paper/29d94106c60ae0b286dfa55bf23fc5710d755c4b

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Epidemiology

1. D. Sinclair
2. W. Ying
3. W. Kraus
4. Jun Yoshino
5. Raga Krishnakumar
6. Joseph A. Baur
7. Johan Auwerx
8. E. Verdin

In Geriatrics and Gerontology

1. Johan Auwerx
2. D. Sinclair
3. Joseph A. Baur
4. S. Imai
5. C. Cantó
6. E. Verdin
7. Jun Yoshino
8. R. Houtkooper

In Oncology

1. Johan Auwerx
2. W. Kraus
3. Jun Yoshino
4. C. Cantó
5. Joseph A. Baur
6. S. Imai
7. W. Ying
8. Raga Krishnakumar

Citations in the corpus

• The PARP Side of the Nucleus: Molecular Actions, Physiological Outcomes, and Clinical Targets (2010, positive): “For example, stress-induced cell death due to PARP-1-dependent NAD+ depletion in cardiomyocytes can be reversed by overexpression of NAMPT (Pillai et al., 2005), supporting the conclusion that NAMPT catalyzes a rate-limiting step in NAD+ synthesis (Revollo et al., 2004).”
• Sirt3 blocks the cardiac hypertrophic response by augmenting Foxo3a-dependent antioxidant defense mechanisms in mice. (2009, background): “Another report has shown that increased utilization of nicotinamide, a noncompetitive inhibitor of SIRT1, by the enzyme nicotinamide phosphoribosyl transferase (Nampt), which recycles nicotinamide in the NAD de novo cycle, regulates the SIRT1 levels (33).”
• Glucose restriction inhibits skeletal myoblast differentiation by activating SIRT1 through AMPK-mediated regulation of Nampt. (2008, background): “Overexpression of exogenous Nampt regulates the transcriptional activity of a transiently transfected Gal-SIRT1 fusion protein in mammalian cells (Revollo et al., 2004).”
• Sirt3-Mediated Deacetylation of Evolutionarily Conserved Lysine 122 Regulates MnSOD Activity in Response to Stress (2010, background): “Nicotinamide phosphoribosyl transferase (NAMPT) enhances cellular NAD levels and increases Sirt1 transcriptional activity in a dose-dependent manner (Revollo et al., 2004), so it seemed reasonable to determine if NAMPT levels are increased in our fasting mice and whether this induces Sirt3.”
• The secret life of NAD+: an old metabolite controlling new metabolic signaling pathways. (2010, background): “Not surprisingly, the effects of SIRT1 on pancreatic function go hand in hand with those of NAD metabolism (36, 57), suggesting again a causal relationship where SIRT1 translates alterations of NAD levels into transcriptional events.”
• Nutrient-sensitive mitochondrial NAD+ levels dictate cell survival. (2007, background): “These data are consistent with other studies showing that Nampt catalyzes a rate-limiting step in nucleo-cytoplasmic NAD biosynthesis (Pillai et al., 2005; Revollo et al., 2004).”
• Sirtuins: critical regulators at the crossroads between cancer and aging (2007, background): “Overexpression of Nampt increases NADþ levels and induces SIRT1 activity, with changes in gene expression paralleling those in cells overexpressing SIRT1 (Revollo et al., 2004).”
• PARPs and ADP-ribosylation: recent advances linking molecular functions to biological outcomes (2017, background): “More broadly, a number of studies have shown that modulation of cellular NAD+ levels can regulate the catalytic activities of sirtuins (Anderson et al. 2002, 2003; Araki et al. 2004; Revollo et al. 2004); presumably, similar mechanisms can regulate the catalytic activities of PARPs as well.”
• NAD+/NADH and NADP+/NADPH in Cellular Functions and Cell Death: Regulation and Biological Consequences (2008, positive): “Recent studies have indicated multiple novel and interesting properties of Nampt—-another key enzyme in NAD synthesis: it has been demonstrated that three seemingly different proteins—-Nampt, the presumptive cytokine pre-B-cell colony-enhancing factor (PBEF), and a new visceral fat-derived hormone v”