The ligand binding domain of peroxisome proliferator-activated receptors
The ligand binding domain (LBD) of peroxisome proliferator-activated receptors (PPAR): Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily of ligand-activated transcription factors. PPARs play important roles in regulating cellular differentiation, development and lipid metabolism. Activated PPAR forms a heterodimer with the retinoid X receptor (RXR) that binds to the hormone response element located upstream of the peroxisome proliferator responsive genes and interacts with co-activators. There are three subtypes of peroxisome proliferator activated receptors, alpha, beta (or delta), and gamma, each with a distinct tissue distribution. Several essential fatty acids, oxidized lipids and prostaglandin J derivatives can bind and activate PPAR. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, PPAR has a central well conserved DNA binding domain (DBD), a variable N-terminal regulatory domain, a flexible hinge a nd a C-terminal ligand binding domain (LBD).