Name

NAMPTP2 Gene

nicotinamide phosphoribosyltransferase pseudogene 2

NAMPTP1 Gene

nicotinamide phosphoribosyltransferase pseudogene 1

NAMPT Gene

nicotinamide phosphoribosyltransferase

This gene encodes a protein that catalyzes the condensation of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to yield nicotinamide mononucleotide, one step in the biosynthesis of nicotinamide adenine dinucleotide. The protein belongs to the nicotinic acid phosphoribosyltransferase (NAPRTase) family and is thought to be involved in many important biological processes, including metabolism, stress response and aging. This gene has a pseudogene on chromosome 10. [provided by RefSeq, Feb 2011]

NNMT Gene

nicotinamide N-methyltransferase

N-methylation is one method by which drug and other xenobiotic compounds are metabolized by the liver. This gene encodes the protein responsible for this enzymatic activity which uses S-adenosyl methionine as the methyl donor. [provided by RefSeq, Jul 2008]

NMRK2 Gene

nicotinamide riboside kinase 2

Enables ribosylnicotinamide kinase activity and ribosylnicotinate kinase activity. Predicted to be involved in NAD metabolic process. Predicted to act upstream of or within negative regulation of myoblast differentiation. Located in nucleoplasm and plasma membrane. [provided by Alliance of Genome Resources, Mar 2025]

NMRK1 Gene

nicotinamide riboside kinase 1

Nicotinamide adenine dinucleotide (NAD+) is essential for life in all organisms, both as a coenzyme for oxidoreductases and as a source of ADP-ribosyl groups used in various reactions. Nicotinic acid and nicotinamide, collectively known as niacin, are the vitamin precursors of NAD+. Nicotinamide riboside kinases, such as NRK1, function to synthesize NAD+ through nicotinamide mononucleotide using nicotinamide riboside as the precursor (Bieganowski and Brenner, 2004 [PubMed 15137942]).[supplied by OMIM, Mar 2008]

NMNAT2 Gene

nicotinamide nucleotide adenylyltransferase 2

This gene product belongs to the nicotinamide mononucleotide adenylyltransferase (NMNAT) enzyme family, members of which catalyze an essential step in NAD (NADP) biosynthetic pathway. Unlike the other human family member, which is localized to the nucleus, and is ubiquitously expressed; this enzyme is cytoplasmic, and is predominantly expressed in the brain. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

NMNAT3 Gene

nicotinamide nucleotide adenylyltransferase 3

This gene encodes a member of the nicotinamide/nicotinic acid mononucleotide adenylyltransferase family. These enzymes use ATP to catalyze the synthesis of nicotinamide adenine dinucleotide or nicotinic acid adenine dinucleotide from nicotinamide mononucleotide or nicotinic acid mononucleotide, respectively. The encoded protein is localized to mitochondria and may also play a neuroprotective role as a molecular chaperone. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Jan 2011]

NMNAT1 Gene

nicotinamide nucleotide adenylyltransferase 1

This gene encodes an enzyme which catalyzes a key step in the biosynthesis of nicotinamide adenine dinucleotide (NAD). The encoded enzyme is one of several nicotinamide nucleotide adenylyltransferases, and is specifically localized to the cell nucleus. Activity of this protein leads to the activation of a nuclear deacetylase that functions in the protection of damaged neurons. Mutations in this gene have been associated with Leber congenital amaurosis 9. Alternative splicing results in multiple transcript variants. Pseudogenes of this gene are located on chromosomes 1, 3, 4, 14, and 15. [provided by RefSeq, Jul 2014]

NNT Gene

nicotinamide nucleotide transhydrogenase

This gene encodes an integral protein of the inner mitochondrial membrane. The enzyme couples hydride transfer between NAD(H) and NADP(+) to proton translocation across the inner mitochondrial membrane. Under most physiological conditions, the enzyme uses energy from the mitochondrial proton gradient to produce high concentrations of NADPH. The resulting NADPH is used for biosynthesis and in free radical detoxification. [provided by RefSeq, Sep 2016]

HPRT1P1 Gene

hypoxanthine phosphoribosyltransferase 1 pseudogene 1

HPRT1P2 Gene

hypoxanthine phosphoribosyltransferase 1 pseudogene 2

HPRT1P3 Gene

hypoxanthine phosphoribosyltransferase 1 pseudogene 3

APRT Gene

adenine phosphoribosyltransferase

Adenine phosphoribosyltransferase belongs to the purine/pyrimidine phosphoribosyltransferase family. A conserved feature of this gene is the distribution of CpG dinucleotides. This enzyme catalyzes the formation of AMP and inorganic pyrophosphate from adenine and 5-phosphoribosyl-1-pyrophosphate (PRPP). It also produces adenine as a by-product of the polyamine biosynthesis pathway. A homozygous deficiency in this enzyme causes 2,8-dihydroxyadenine urolithiasis. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

NAPRT Gene

nicotinate phosphoribosyltransferase

Nicotinic acid (NA; niacin) is converted by nicotinic acid phosphoribosyltransferase (NAPRT; EC 2.4.2.11) to NA mononucleotide (NaMN), which is then converted to NA adenine dinucleotide (NaAD), and finally to nicotinamide adenine dinucleotide (NAD), which serves as a coenzyme in cellular redox reactions and is an essential component of a variety of processes in cellular metabolism including response to stress (Hara et al., 2007).[supplied by OMIM, Mar 2008]

UPRT Gene

uracil phosphoribosyltransferase (FUR1) homolog (S. cerevisiae)

This gene encodes uracil phosphoribosyltransferase, which catalyzes the conversion of uracil and 5-phosphoribosyl-1-R-diphosphate to uridine monophosphate (UMP). This reaction is an important part of nucleotide metabolism, specifically the pyrimidine salvage pathway. The enzyme localizes to the nucleus and cytoplasm. The protein is a potential target for rational design of drugs to treat parasitic infections and cancer. [provided by RefSeq, Nov 2009]

QPRT Gene

quinolinate phosphoribosyltransferase

This gene encodes a key enzyme in catabolism of quinolinate, an intermediate in the tryptophan-nicotinamide adenine dinucleotide pathway. Quinolinate acts as a most potent endogenous exitotoxin to neurons. Elevation of quinolinate levels in the brain has been linked to the pathogenesis of neurodegenerative disorders such as epilepsy, Alzheimer's disease, and Huntington's disease. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015]

HPRT1 Gene

hypoxanthine phosphoribosyltransferase 1

The protein encoded by this gene is a transferase, which catalyzes conversion of hypoxanthine to inosine monophosphate and guanine to guanosine monophosphate via transfer of the 5-phosphoribosyl group from 5-phosphoribosyl 1-pyrophosphate. This enzyme plays a central role in the generation of purine nucleotides through the purine salvage pathway. Mutations in this gene result in Lesch-Nyhan syndrome or gout.[provided by RefSeq, Jun 2009]