RFG (ARA70, ELE1) Interacts with the Human Androgen Receptor in a Ligand-Dependent Fashion, but Functions Only Weakly as a Coactivator in Cotransfection Assays

Abnormalities of the human androgen receptor (hAR) cause a range of clinical defects in male development. A large proportion of these mutations are single amino acid substitutions in the hormone-binding domain (HBD) that alter AR function by interfering with the capacity of the AR to bind androgen or to form stable hormone-receptor complexes. Prior studies have suggested that the formation of such stable, active hormone-receptor complexes is a crucial step in the modulation of genes by the AR. It is presumed that these hormone-receptor complexes interact with other proteins to participate in the formation of active transcription complexes at the initiation sites of androgen-responsive genes. Using a yeast two-hybrid screening method, we isolated a partial cDNA encoding the carboxy terminus of a protein that interacts with the hAR-HBD (amino acid residues 623–917) in a ligand-dependent fashion in a yeast two-hybrid assay. Sequence analysis of this clone revealed that it encoded a portion of a protein that ...