Identification of a Functional Androgen-Response Element in the Exon 1-Coding Sequence of the Cystatin-Related Protein Gene crp2

Two hormone-responsive segments, one in the region of the promoter and one in intron 1, are identified in two homologous androgen-regulated and differentially expressed rat genes encoding the cystatin-related proteins (CRPs). Footprint analysis with the androgen receptor (AR) DNA-binding domain on the promoter-containing fragments reveals an AR-binding site downstream of the transcription start point in the crp2 gene (ARBSd/crp2,+ 40/+63). It displays an androgen response element-like sequence motif 5′-AGAAGAaaaTGTACA-3′ and overlaps with the ATG translation start codon. A double-stranded oligonucleotide containing this sequence forms a DNA-protein complex with the full-length AR synthesized by vaccinia, as seen in band shift assays. Additional AR-binding sites, ARBSu/crp1 and ARBSu/crp2, occur 5′ upstream of the transcription start point and are located at an identical position (−142/−120) in crp1 and crp2. The AR affinity for these two slightly different sequence motifs is relatively weak. The biologica...