Mapping of an inducible element in the T cell receptor V beta 2 promoter.
The murine V beta 2 promoter was analyzed for an element regulating phorbol ester inducibility of the TCR beta chain gene. In transient expression analysis of 5' nested deleted fragments of the V beta 2 promoter, the TPA-inducible element mapped between -85 and -42. The -85 to -62 oligo conferred 12-0-tetradecanoylphorbol-13-acetate (TPA) inducibility to the heterologous TPA-uninducible thymidine kinase promoter. The -85 to -62 region contained an AP-1 site (-85 to -72) and inverted repeat motif (-72 to -62). The AP-1 site required the 3' flanking inverted repeat region for conferring optimal inducibility. In vitro transcribed and translated jun/fos heterodimers bind to the V beta 2 AP-1 motif with a 16-fold lower affinity as compared to the collagenase AP-1 motif. This explains the inability of the V beta 2 AP-1 motif to confer optimal TPA inducibility by itself. The affinity of jun/fos heterodimers for the V beta 2 AP-1 motif was not increased by the presence in cis of the inverted repeat motif. The 3' flanking inverted repeat binds the ets transactivator but not jun/fos heterodimers. The demonstrated cooperativity between the AP-1 and the 3' flanking sequence to confer TPA inducibility can thus be explained by the individual contributions of jun/fos and ets transactivators.
Messier
H
H
Department of Immunology, University of Alberta, Edmonton, Canada.
Ratanavongsiri
J
J
Fuller
T
T
Mangal
S
S
Kilgannon
P
P
Fotedar
R
R
Fotedar
A
A
D000818:Animals; D001483:Base Sequence; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D051379:Mice; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D011401:Promoter Regions, Genetic; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013937:Thymidine Kinase / Q000235:genetics
D004268:DNA-Binding Proteins; D009838:Oligodeoxyribonucleotides; D016755:Proto-Oncogene Proteins c-jun; D016693:Receptors, Antigen, T-Cell, alpha-beta; D013937:Thymidine Kinase; D013755:Tetradecanoylphorbol Acetate