PPARG Epigenetic Deregulation and Its Role in Colorectal Tumorigenesis

Figure 2

(a) PPARG schematic structure at chromosome 3p25. The arrows indicate the transcription start sites for each specific mRNA isoform; the boxes indicate the exons. (b) The four mature transcribed mRNAs are depicted. (c) The PPARG1, 3, and 4 mRNA isoforms are translated into the unique PPARγ1 protein; the PPARG2 transcript is translated into PPARγ2, containing 28 additional amino acids at its N-terminal region. The four functional domains of the mature protein are reported. (d) PPARγ mechanisms of action. Transactivation: in the presence of ligands, PPARγ binds the cognate PPRE as heterodimer with RXR and activates gene expression. Transrepression: in the presence of ligands, the SUMOylated form of the receptor interacts with others transcription factors, such as NFκB, and represses their target genes transcription, adapted from reference [26].