Figure 2.

Coexpression of GRIP1 in yeast increases the transactivation by TRβ₁ and TRα₁ homodimers in response to T3 ligand. Yeast transformants expressing TRs alone or with GRIP1 and containing β-gal reporter genes with a single copy of DR4 (Top), F2 (Middle), or PAL (Bottom) response element as TREs were grown for 16 hr in the presence of no ligand (open bars) or 1 μM T3 (shaded bars) and β-gal was assayed [U, Miller unit (39)].