IDENTIFICATION OF CELLULAR PROTEIN THAT CAN INTERACT SPECIFICALLY WITH THE BASIC HELIX-LOOP-HELIX DOMAIN OF THE AROMATIC HYDROCARBON RECEPTOR

The Ah receptor is a basic helix-loop-helix (bHLH)-PAS protein and fun ctions as a ligand-activated DNA binding protein directly interacting with target genes by binding to xenobiotic responsive elements. We hav e sought to identify possible cellular proteins that can interact with the Ah receptor. The bHLH domain of the Ah receptor was fused to glut athione-S-transferase (GST), and the resulting fusion protein was used as a probe to help us to identify receptor associated protein(s). At least one such protein, 45kDa (p45), was detected in mouse lives extra cts, but it does not bind to the bHLH domain of the Ah receptor nuclea r translocator, nor to the transactivation domain of Ah receptor or GS T alone. (C) 1995 Academic Press, Inc.