GST-25-kD CF Im subunit binds U1 70K protein. The first three lanes show the intensity of one-half of the input amounts of in vitro synthesized 35S-met-labeled luciferase, 68-kD CF Im subunit, and U1 70K protein. The next three lanes show the bead controls where the labeled proteins were incubated with uncharged glutathione beads. The next three lanes show the binding resulting from incubating the labeled proteins with glutathione beads charged with GST-25-kD CF Im subunit (GST CF I 25). The last two lanes show the binding resulting from incubating the labeled proteins with glutathione beads charged with a nonspecific GST fusion protein, GST-IκB. Bound proteins were eluted from the beads and separated by SDS-PAGE (see Materials and Methods).
