Figure 14.

Cooperative effect of increasing concentrations of mutant RXRα LBD and SR11237 on promoting recruitment of coactivator CBP-1 by the PPARγ LBD. One-hundred nanomolar sGFP-PPARγ LBD was used throughout. Recruitment of biotin-labeled CBP-1 coactivator peptide (12 nM) coupled to Tb-SA (12 nM) was detected as an increase in homogeneous time-resolved FRET. The recruitment was stimulated by titration of SR11237 (up to 100 μM) and/or unlabeled mutant RXRα LBD (up to 8 μM; mutations blocking cofactor recruitment) and referenced to activation of isolated sGFP-PPARγ LBD by its agonist rosiglitazone. Data are the mean; N = 2 (SD is reported separately in the Supplemental Data). CBP-1, CREB-binding protein coactivator motif 1; LBD, ligand-binding domain; PPAR, peroxisome proliferator-activated receptor; RXR, retinoid X receptor; sGFP, super folder green fluorescent protein; Tb-SA, terbium cryptate conjugated to streptavidin.