Figure 2: General Schematics of PPAR function. General mechanisms of (a) genomic expression and (b) transrepression of gene expression by PPAR/RXR heterodimers. In (a), upon ligand binding PPAR associates with RXR and coactivator to turn on target genes via the PPAR response element (PPRE). In (b), blocking the dissociation of corepressor from transcription factor at the gene locus, association of transcription factor to PPAR/RXR by tethering, and association of coactivator with PPAR/RXR by squelching, inhibit the transcription of different genes. R = corepressors, filled circle = ligand, A = coactivators, TF = transcription factor. Su indicates modulation by small regulatory protein (sumoylation).