PPARδ represses transcription and interacts with corepressors.
(A) PPARδ represses basal transcription. CV-1 cells
were transfected with GAL4 DBD or GAl4-PPAR fusions. Normalized
luciferase activity was 8.94 for GAL4 DBD, 12.58 for GAL4-PPARα, 9.45
for PPARγ, and 0.19 for PPARδ. Fold repression was determined
relative to the GAL4 DBD activity. (B) PPARδ interacts
with SMRT and NCoR. CV-1 cells were transfected with GAL4-SMRT RID
(G4-SMRT) or NCoR RID (G4-NCoR) together with VP or VP-PPARδ.
(C) PPARδ LBD interacts with SMRT. CV-1 cells were
transfected with G4-SMRT and VP, VP-PPARδ, or VP-PPARδ LBD
(VP-δLBD). (D) The ID1 of SMRT interacts with PPARδ.
Transfection was performed with VP-PPARδ and GAL4 DBD or GAL4 fusion
of SMRT ID1, ID2, and three ID1 mutants.