Recombinant Human Pre-B-Cell Colony-Enhancing Factor 1/PBEF/Visfatin (N-6His)

Source: E.coli. MW :57kD. Recombinant Human Visfatin is produced by our E.coli expression system and the target gene encoding Met1-His491 is expressed with a 6His tag at the N-terminus. Pre-B cell colony enhancing factor (PBEF) was originally identified as a cytokine that potentiated the clonal expansion and differentiation of pre-B cells, but it is also acknowledged to be the ubiquitous intracellular enzyme nicotinamide phosphoribosyltranferase (NAMPT) and the adipokine "visfatin". PBEF is constitutively expressed in the fetal membranes where its greatest expression is in the amnion. It has intracellular and extracellular forms. Most of the intracellular functions of PBEF are due to its role as a Nampt which can induce angiogenesis through upregulation of VEGF and VEGFR and secretion of MCP-1. Extracellular PBEF has been shown to increase inflammatory cytokines, such as TNF-a, IL-1 beta, IL-16, and TGF- beta1. PBEF also increases the production of IL-6, TNF-a, and IL-1 beta in CD14+ monocyctes, macrophages, and dendritic cells, enhances the effectiveness of T cells. Protein function: Catalyzes the condensation of nicotinamide with 5- phosphoribosyl-1-pyrophosphate to yield nicotinamide mononucleotide, an intermediate in the biosynthesis of NAD. It is the rate limiting component in the mammalian NAD biosynthesis pathway. The secreted form behaves both as a cytokine with immunomodulating properties and an adipokine with anti-diabetic properties, it has no enzymatic activity, partly because of lack of activation by ATP, which has a low level in extracellular space and plasma. Plays a role in the modulation of circadian clock function. NAMPT-dependent oscillatory production of NAD regulates oscillation of clock target gene expression by releasing the core clock component: CLOCK-ARNTL/BMAL1 heterodimer from NAD-dependent SIRT1-mediated suppression. [The UniProt Consortium]