Repression of retinoic acid-induced transactivation by embryonal LTR binding protein.
The mechanism of repression of transcription by ELP, the embryonal long terminal repeat binding protein, was investigated. ELP represses the Moloney murine leukemia virus long terminal repeat by binding to a site which overlaps with a sequence element for retinoic acid receptor binding. This suggests possible competition of ELP with retinoic acid receptor for the same sequence elements. Oligonucleotides corresponding to ELP and/or retinoic acid receptor binding elements were placed upstream of the SV40 promoter and their effect on gene expression was analyzed by CAT assay. Elements which have affinity to both ELP and retinoic acid receptor were activated by retinoic acid receptor and these activations were repressed by ELP. An ELP binding element without affinity to retinoic acid receptor was insensitive to both activation by retinoic acid receptor and repression by ELP. Furthermore, cellular ELP binding elements and the Moloney leukemia virus long terminal repeat were activated by retinoic acid. These data suggest that one of the mechanism of transcriptional repression by ELP is competition for binding sites with transactivators such as retinoic acid receptors.
Kotomura
N
N
Department of Molecular Pathology, Hiroshima University.
Okada
M
M
Ninomiya
Y
Y
Tsukiyama
T
T
Umesono
K
K
Evans
R M
RM
Niwa
O
O
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D018398:Homeodomain Proteins; D051379:Mice; D008969:Molecular Sequence Data; D008979:Moloney murine leukemia virus / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D018160:Receptors, Cytoplasmic and Nuclear; D018168:Receptors, Retinoic Acid / Q000378:metabolism / Q000502:physiology; D012097:Repressor Proteins / Q000378:metabolism / Q000494:pharmacology*; D000072482:Retinoic Acid Receptor alpha; D012680:Sensitivity and Specificity; D054339:Steroidogenic Factor 1; D014157:Transcription Factors; D015533:Transcriptional Activation / Q000187:drug effects*; D014162:Transfection; D014212:Tretinoin / Q000037:antagonists & inhibitors* / Q000494:pharmacology*
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; C000607072:Rara protein, mouse; D018160:Receptors, Cytoplasmic and Nuclear; D018168:Receptors, Retinoic Acid; D012097:Repressor Proteins; D000072482:Retinoic Acid Receptor alpha; D054339:Steroidogenic Factor 1; D014157:Transcription Factors; D014212:Tretinoin