Nicotinamide phosphoribosyltransferase (Nampt; pre-B cell colony-enhancing factor; PBEF; Visfatin) is an 52kD adipokine secreted by adipose tissue and involved in the biosynthesis of nicotinamide adenine dinucleotide (NAD+). Two forms of Nampt exist, an intracellular form (iNampt) and an extracellular form (eNampt). While the function of iNampt as an essential and rate-limiting NAD+ biosynthetic enzyme is well established, the physiological role of eNampt is still a matter of debate. Nampt has various functions, including the promotion of vascular smooth muscle cell maturation and inhibition of neutrophil apoptosis. It activates insulin receptor and has insulin-mimetic effects, lowering blood glucose and improving insulin sensitivity. The protein is highly expressed in visceral fat and serum levels of the protein correlate with obesity.
Biological Activity:Shows adipogenic effects in stimulated differentiating 3T3-L1 cells.
Sequence:Human Nampt (visfatin/PBEF) (aa1-491) is fused at the N-terminus to a FLAG®-tag.
Storage and Stability:Lyophilized powder may be stored at -20°C. Stable for 12 months after receipt at -20°C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
