Visfatin (VF)

Visfatin, an adipocytokine that is highly enriched in the visceral fat of both Mouses and mice and whose expression level in plasma increases during the development of obesity. Visfatin corresponds to pre-B cell colony-enhancing factor (PBEF), a 52-kD cytokine expressed in lymphocytes. The gene encoding PBEF was originally isolated from an activated lymphocyte cDNA library.The 3-prime UTR of PBEF contains several TATT motifs, destabilizing sequences characteristic of cytokine messages. The deduced 473-amino acid protein has a calculated molecular mass of 52 kDa. PBEF has a hydrophobic N terminus, 2 N-glycosylation sites, several putative phosphorylation sites, and 6 cysteines. Northern blot analysis detected transcripts of about 2.0, 2.4, and 4.0 kb in all tissues examined, with highest expression in liver, followed by muscle.