Fig. 7. The HDAC3-containing SMRT and N-CoR complexes interact with unliganded TR. HeLa nuclear extracts were incubated with the immobilized GST control or GST–TR fusion protein. The super natants and bound fractions were then fractionated by SDS–PAGE and analyzed by western blotting using the antibodies indicated. The HeLa NE (nuclear extract) in lane 1 and FT (supernatant) in lanes 2 and 4 were equivalent to 20% of the HeLa nuclear extracts used for pull-down.