Fig. 1. Identification of TGIF as a mSin3-interacting protein. A, mSin3 and TGIF are shown schematically, together with the LexA-PAH2 fusion used as a bait in the two hybrid screen and the VP16 activation domain fusions to TGIF isolated. B, TGIF interacts directly with the PAH2 domain of mSin3. His 6-tagged bacterially expressed TGIF was incubated with glutathione agarose alone (Lane 4; beads) or in the presence of purified GST or GST-PAH2 as indicated (Lanes 5 and 6). After extensive washing, bound proteins were separated by SDS-PAGE and visualized by Coomassie blue staining. A portion of each of the input proteins is shown (Lanes 1–3), and the GST-PAH2-bound TGIF is indicated.