title: Steroid-dependent interaction of transcription factors with the inducible promoter of mouse mammary tumor virus in vivo.
abstract: We have used exonuclease protection in vivo as an assay to detect interaction of nuclear factors with the steroid-inducible promoter of mouse mammary tumor virus. Binding of two factors is detected uniquely at the steroid-activated promoter, and results in protection of sequences between -82 and approximately +12 One factor is identified as the murine homolog of nuclear factor 1. The second (designated factor i) binds downstream of nuclear factor 1 and protects sequences extending over the cap site. Binding activities associated with both factors can be detected in crude nuclear extracts; their apparent concentrations are unaffected by hormone treatment of the cells. These results demonstrate that glucocorticoid induction of transcription results from receptor-mediated establishment of a transcription factor complex at the promoter rather than activation of a preexisting complex.
mesh_terms: D000818:Animals; D002460:Cell Line; D002843:Chromatin / Q000378:metabolism; D004279:DNA, Viral / Q000378:metabolism; D003907:Dexamethasone / Q000378:metabolism / Q000494:pharmacology*; D005090:Exodeoxyribonucleases / Q000378:metabolism; D005814:Genes, Viral; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D051379:Mice; D011401:Promoter Regions, Genetic; D011965:Receptors, Glucocorticoid / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D002843:Chromatin; D004279:DNA, Viral; D011965:Receptors, Glucocorticoid; D014157:Transcription Factors; C028697:dexamethasone receptor; D003907:Dexamethasone; D005090:Exodeoxyribonucleases; C020133:exodeoxyribonuclease III