Ligand-inducible retinoid X receptor-mediated protein: DNA interactions in the retinoic acid receptor beta2 gene promoter in vivo.
Retinoid X receptors (RXRs) are recently characterized transcription factors that are members of the nuclear hormone receptor superfamily. However, it is not known whether the endogenous RXR complex requires its ligand for access to its hormone response element (HRE) of a target gene in vivo. Hence, dimethyl sulfate-based genomic footprinting was carried out to examine occupancy of HREs in the retinoic acid (RA) receptor beta2 (RARbeta2) gene promoter in the murine melanoma cell line S91 cultured in the absence or presence of T3, all-trans-RA (atRA), or CD2624, an RXR-selective retinoid. No footprint was observed at the RA-response element (betaRARE) in the absence of ligands. However, a footprint was detected at the betaRARE and other cis-acting elements after a 6 h incubation with CD2624 and atRA. Interestingly, only the betaRARE was footprinted after 60 min incubation with CD2624. These results suggest that the endogenous RXR complex can interact with an HRE of a target gene in the presence of ligand, and subsequently may initiate additional interactions between DNA and other transcription factors.
Ikeda
M
M
The Third Department of Internal Medicine, Yamanashi Medical University, Tamaho, Japan.
Spanjaard
R A
RA
Noordhoek
E W
EW
Kawaguchi
A
A
Onaya
T
T
Chin
W W
WW
D000818:Animals; D001565:Benzoates / Q000494:pharmacology; D004247:DNA / Q000378:metabolism*; D018983:DNA Footprinting; D019281:Dimerization; D005786:Gene Expression Regulation / Q000187:drug effects; D008156:Luciferases / Q000235:genetics; D008546:Melanoma, Experimental / Q000378:metabolism; D051379:Mice; D009281:Naphthalenes / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D018168:Receptors, Retinoic Acid / Q000235:genetics* / Q000502:physiology*; D011993:Recombinant Fusion Proteins; D047488:Retinoid X Receptors; D014157:Transcription Factors / Q000378:metabolism* / Q000502:physiology*; D014162:Transfection; D014212:Tretinoin / Q000494:pharmacology; D014284:Triiodothyronine / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D001565:Benzoates; C111955:CD 2624; D009281:Naphthalenes; D018168:Receptors, Retinoic Acid; D011993:Recombinant Fusion Proteins; D047488:Retinoid X Receptors; D014157:Transcription Factors; D014284:Triiodothyronine; D014212:Tretinoin; D004247:DNA; D008156:Luciferases