title: Regulation of NAD biosynthetic enzymes modulates NAD-sensing processes to shape mammalian cell physiology under varying biological cues.
abstract: In addition to its role as a redox coenzyme, NAD is a substrate of various enzymes that split the molecule to either catalyze covalent modifications of target proteins or convert NAD into biologically active metabolites. The coenzyme bioavailability may be significantly affected by these reactions, with ensuing major impact on energy metabolism, cell survival, and aging. Moreover, through the activity of the NAD-dependent deacetylating sirtuins, NAD behaves as a beacon molecule that reports the cell metabolic state, and accordingly modulates transcriptional responses and metabolic adaptations. In this view, NAD biosynthesis emerges as a highly regulated process: it enables cells to preserve NAD homeostasis in response to significant NAD-consuming events and it can be modulated by various stimuli to induce, via NAD level changes, suitable NAD-mediated metabolic responses. Here we review the current knowledge on the regulation of mammalian NAD biosynthesis, with focus on the relevant rate-limiting enzymes. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications.
authors.affiliation: Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy.
authors.forename: Silverio
authors.initials: S
authors.lastname: Ruggieri
authors.affiliation: Department of Clinical Sciences, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Orsomando
authors.affiliation: Department of Clinical Sciences, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Sorci
authors.affiliation: Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy. Electronic address: n.raffaelli@univpm.it.
authors.forename: Nadia
authors.initials: N
authors.lastname: Raffaelli
mesh_terms: D000818:Animals; D003463:Cues; D006801:Humans; D009243:NAD / Q000096:biosynthesis*; D054409:Nicotinamide Phosphoribosyltransferase / Q000502:physiology; D010430:Pentosyltransferases / Q000502:physiology; D037761:Sirtuins / Q000502:physiology; D000098553:Nicotinate-Nucleotide Diphosphorylase (Carboxylating)
chemical_list: D009243:NAD; D010430:Pentosyltransferases; D054409:Nicotinamide Phosphoribosyltransferase; D000098553:Nicotinate-Nucleotide Diphosphorylase (Carboxylating); D037761:Sirtuins; C021864:nicotinate phosphoribosyltransferase
keywords: Enzyme regulation; NAD biosynthesis; Nicotinamide phosphoribosyltransferase; Nicotinamide riboside kinase; Nicotinic acid phosphoribosyltransferase; Quinolinate phosphoribosyltransferase