FIG. 6.
GT198 is a nuclear receptor coactivator. (A) CV-1 cells were cotransfected in 24-well plates with MMTV luciferase reporter (100 ng), GR (10 ng), and GT198 (200 ng), or empty vector as control. Cells were grown in the presence of increasing amounts of dexamethasone (Dex) for GR (0, 10−11, 10−10, 10−9, 10−8, and 10−7 M). (B) CV-1 cells were transfected with the indicated luciferase reporters containing different minimal enhancer elements (2XGRE, 2XERE, F2 TRE, and 5XCRE) (100 ng). GT198 (200 ng), AR, GR, PR, ERα, ERβ, or TRβ1 (10 ng) and inducer plasmid containing the catalytic subunit of PKA (20 ng) for CRE were also cotransfected. For nuclear receptors, each cognate ligand (100 nM) was added to the medium 24 h after the transfection (mibolerone for AR, dexamethasone for GR, progesterone for PR, 17β-estradiol for ERα or ERβ, and T3 for TRβ1). Ligand-dependent activities are shown as the means of triplicate transfections ± standard errors.