[Peroxisome proliferator-activated receptor(PPAR)--structure, function, tissue distribution, gene expression].

Peroxisome proliferator-activated receptors(PPARs, alpha, beta/delta, and gamma) are members of the nuclear receptor superfamily of ligand-activated transcription factors. PPAR has been shown to be regulated the expression of genes involved in lipid metabolism by various compounds such as fibrates, thiazolidinediones, prostaglandins, and fatty acids that is important in adipocyte differentiation and glucose homeostasis. PPARs form a heterodimer with the retinoid X receptor(RXR) and bind to specific DNA sequences located upstream of peroxisome proliferator responsive genes and interact with co-activators, including SRC-1 family, CBP/p300 or TRAP/DRIP complex by ligand dependent way. It is suggested that the selective interactions of PPAR with coactivators induced by PPAR's compounds specify the biological activities of the its compounds. Such differential combinations of transcription factors/coactivators are believed to activate only particular sets of target gene promoters.