FIG. 6.

XAP2 is a subunit stably associated with the unliganded AhR core complex in COS-1 and Hepa 1 cells. (A) COS-1 cells were transfected with 9 μg of pcDNA3/βmAhR-FLAG or pcDNA3, immunoabsorbed with M2 affinity gel, resolved on SDS-PAGE, blotted, and probed with antibodies raised against the AhR (RPT1), hsp90 (hsp 86/84), and XAP2. Lanes: 1, pcDNA3/βmAhR-FLAG; 2, pcDNA3/βmAhR-FLAG with M2 resin blocked with FLAG peptide; 3, pcDNA3 (cytosol from Hepa 1 cells was immunoabsorbed with polyclonal AhR antisera or rabbit immunoglobulin G, resolved on SDS-PAGE, and used for immunoblot analysis); 4, polyclonal AhR antisera; 5, rabbit IgG.