Molecular interaction of retinoic acid receptors with coregulators PCAF and RIP140.
p300/CBP-associating factor (PCAF) is a ligand-dependent coactivator, whereas receptor-interacting protein 140 (RIP140) is a ligand-dependent negative coregulator for retinoic acid (RA) receptor (RAR) and retinoid X receptor (RXR). To compare these molecular interactions and to determine the effect of RXR ligands, we focus on PCAF/RAR/RXR complex formation in this study for a comparison to RIP140/RAR/RXR complex formation. The LBD of RXR is identified as its primary PCAF-interacting motif. BIAcore studies determine the Kd of RAR/RXR association with PCAF as 9.35 nM in the presence of RXR ligand AGN194204, and 47.2 nM in the absence of ligand. Cross-linking study demonstrates tri-molecular complex consisting of one RAR/RXR pair and one PCAF. In competition experiments, RIP140 strongly competes with PCAF for interaction with RAR/RXR both in vitro and in vivo. Chromatin immunoprecipitation demonstrates recruitment of RIP140 and PCAF to the endogenous RA-regulated gene, the RARbeta2 promoter. This study presents kinetic evidence for competition of RIP140 with PCAF for ligand-dependent interactions with RAR/RXR, and provides kinetic explanation for the suppressive activity of RIP140 in RA-activated gene expression.
Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church St. SE, Minneapolis, MN 55455, USA.
Yixin
Y
Chen
Xinli
X
Hu
Li-Na
LN
Wei
D000123:Acetyltransferases / Q000378:metabolism*; D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D002843:Chromatin / Q000378:metabolism; D003432:Cross-Linking Reagents; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D051548:Histone Acetyltransferases; D006801:Humans; D047468:Immunoprecipitation; D007700:Kinetics; D008024:Ligands; D009687:Nuclear Proteins / Q000378:metabolism*; D000078723:Nuclear Receptor Interacting Protein 1; D018168:Receptors, Retinoic Acid / Q000378:metabolism*; D047488:Retinoid X Receptors / Q000378:metabolism*; D020349:Surface Plasmon Resonance; D014157:Transcription Factors / Q000378:metabolism*; D014212:Tretinoin / Q000494:pharmacology*; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor
D000123:Acetyltransferases; D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins; D002843:Chromatin; D003432:Cross-Linking Reagents; D005982:Glutathione Transferase; D051548:Histone Acetyltransferases; D008024:Ligands; D009687:Nuclear Proteins; D000078723:Nuclear Receptor Interacting Protein 1; D018168:Receptors, Retinoic Acid; D047488:Retinoid X Receptors; D014157:Transcription Factors; D014212:Tretinoin; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor; C000627127:NRIP1 protein, human