Figure 4.

Temporal and compositional differences in RXR dimer occupancy at PPARγ:RXR-binding sites in early adipogenesis. (A) Effect of PPARδ and PPARγ knockdown on binding of RXR to target sites at days 0 and 1. Preadipocytes were infected with shRNA-expressing lentivirus prior to confluence. shRNAi directed against LacZ was used as control. Chromatin was isolated at days 0 and 1, and RXR ChIP-PCR was performed for the indicated target sites. Recoveries are shown as the percent of input. (NC) No gene control. (B) PPARγ ChIP-PCR for the indicated target sites on the same chromatin as in A. (C) Day 0 and day 1 preadipocytes were treated with a specific agonist of PPARγ (1 μM BRL49653/rosiglitazone) or PPARδ (1 μM L165041) for 6 h before chromatin was harvested. RNAPII ChIP-PCR was performed using primers located within the body of the indicated genes. RNAPII antibody and DNA were analyzed as in A. All results are representative of a minimum of two independent experiments.