FIG. 8.

Combinatorial interactions of receptors with SMRT in a two-hybrid analysis in vivo. A mammalian two-hybrid protocol similar to that in Fig. 3 was used, but with a pSG5 GAL4DBD-SMRT (amino acids 751 to 1495) construct in all cases and with one or more nuclear hormone receptors being introduced simultaneously as GAL4AD fusions. The cells were incubated in the absence or presence of cognate hormones, as indicated below each panel; the cells were harvested after 48 h, and luciferase activity was determined relative to that of pCH110, used as an internal control (Relative Luc). The results represent the averages and standard deviations from at least two duplicate experiments. (A) Introduction of GAL4AD fusions of RXRα, RARα, or both. (B) Introduction of GAL4AD fusions of RXRα, T3Rα, or both. (C) Introduction of GAL4AD fusions of VDR, RXRα, or both. (D) Introduction of GAL4AD fusions of VDR, T3Rα, or both.