Identification of a functional androgen-response element in the exon 1-coding sequence of the cystatin-related protein gene crp2

Mol Endocrinol. 1997 Jul;11(8):1033-43. doi: 10.1210/mend.11.8.9961.

Abstract

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 biological function of all three AR-binding sites as transcription control elements has been studied. The ARBSd/crp2 element clearly shows androgen-response element characteristics. The contribution of the common upstream element to the androgen-dependent control of reporter gene transcription is less clear. The transcription of a reporter gene construct containing the crp2 footprint fragment crp2F (-273/+88) is hormonally regulated as determined by transfection into the human breast cancer cell line T-47D. Androgens, but also glucocorticoids, efficiently stimulate steroid-dependent transcription of the chloramphenicol acetyltransferase gene. Mutation of the 5'-TGTACA-3' sequence in ARBSd/crp2 destroys the AR binding and abolishes the androgen-dependent synthesis of chloramphenicol acetyltransferase. A large fragment derived from intron 1 of the crp1 and crp2 gene can also provide the androgen-dependent transcription of chimeric constructs in T-47D cells. However, the induction measured is less than the one observed with crp2F (-273/+88), and this activity seems to reside in several subfragments that each display a low but consistent androgen responsiveness.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Androgens / metabolism*
  • Androgens / pharmacology
  • Animals
  • Binding Sites
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cystatins
  • DNA Footprinting
  • DNA Mutational Analysis
  • Deoxyribonuclease I / genetics
  • Deoxyribonuclease I / metabolism
  • Electrophoresis / methods
  • Exons
  • Genes, Reporter
  • Humans
  • Male
  • Proteins / genetics*
  • Proteins / metabolism*
  • RNA, Messenger / drug effects
  • Rats
  • Rats, Wistar
  • Receptors, Androgen / genetics
  • Receptors, Androgen / metabolism*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Regulatory Sequences, Nucleic Acid
  • Transcription, Genetic
  • Transfection
  • Tumor Cells, Cultured

Substances

  • Andpro protein, rat
  • Androgens
  • Cystatins
  • P22k15 protein, rat
  • Proteins
  • RNA, Messenger
  • Receptors, Androgen
  • Recombinant Proteins
  • Deoxyribonuclease I