p300 functions as a coactivator for the peroxisome proliferator- activated receptor α

Abstract

The integrator protein, p300, was demonstrated to interact with mouse peroxisome proliferator-activated receptor α in a ligand-enhanced manner. The PPARα-interacting domain of p300 was mapped to amino acids 39-117 which interacted strongly with PPARα but did not interact with retinoic acid receptor-γ or retinoid X receptor-α. Amino acids within the carboxyl terminus of PPARα as well as residues within the hinge region were required for ligand-dependent interaction with p300. p300 enhanced the transcriptional activation properties of PPARα and, therefore, can be considered a bona fide coactivator for this nuclear receptor. These observations extend the group of p300-interacting proteins to include mPPARα and further characterize the molecular mechanisms of PPARα-mediated transcriptional regulation.