Pax-2/-5/-8 proteins interact directly with Id proteins in vitro. (A) GST pulldown analysis of full-length (FL) Pax-5 and Pax-5(1-175) with GST (lanes 3 and 4) and a GST-Id2 fusion protein (lanes 5 and 6); 20% of the input proteins are shown in lanes 1 and 2. (B) GST pulldown analysis of Pax-2(1-175), Pax-5(1-175), and Pax-8(1-175) with GST (lanes 4 to 6) and a GST-Id2 fusion protein (lanes 7 to 9); 10% of the input proteins are shown in lanes 1 to 3. (C) GST pulldown analysis of full-length Pax-5, MEF2A, NF-κB(p50), and SAP-1 with a GST-Id2 fusion protein (lanes 5 to 8); 10% of the input proteins are shown in lanes 1 to 4. (D) GST pulldown analysis of Pax-5(1-175) with the indicated GST-Id2 fusion proteins. The structures of these proteins are shown diagrammatically (above), and 10% of the input proteins are shown in lane 1.