NAMPT gene

NAMPT (nicotinamide phosphoribosyltransferase) is a protein-coding gene located on chromosome 7q22.3.

The NAMPT gene encodes a protein that catalyzes the condensation of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to form nicotinamide mononucleotide, a step in the biosynthesis of nicotinamide adenine dinucleotide. The encoded protein, called visfatin, belongs to the family of nicotinic acid phosphoribosyltransferases (NAPRTases) and is thought to be involved in many important biological processes, including metabolism, stress response and aging. The NAMPT gene has a pseudogene on chromosome 10 and an important paralog of this gene is NAPRT.

Diseases associated with NAMPT include "ageing" and gestational diabetes. Associated metabolic pathways include NAD metabolism and gene expression (transcription).

The encoded protein(visfatin) catalyzes the condensation of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to form nicotinamide mononucleotide, an intermediate of NAD biosynthesis. It is the rate-determining component in the mammalian NAD biosynthetic pathway.

The secreted form behaves both as a cytokine with immunomodulatory properties and as an adipokine with antidiabetic properties. It has no enzymatic activity, partly due to the lack of activation by ATP, which is only present in small amounts in the extracellular space and plasma.

1. Kanda N et al. (2011) Visfatin enhances CXCL8, CXCL10, and CCL20 production in human keratinocytes. Endocrinology. 152:3155-3164).
2. Mohammadi M et al. (2019) Circulating visfatin levels and cancers risk: A systematic review and meta-analysis. J Cell Physiol 234:5011-5022.
3. Sonoli SS et al (2011) Visfatin--a review. Eur Rev Med Pharmacol Sci 15:9-14.