Characterization of the mouse CD8 beta chain-encoding gene promoter region.
We identified a regulatory region of the mouse CD8 beta chain-encoding gene (CD8b) promoter. The CD8b 5' upstream sequence could not drive the expression of the bacterial chloramphenicol acetyltransferase (CAT) gene without T-cell receptor or SV40 enhancer elements. The results of transient transfection assays indicated that the dominant transcription-activating element within the CD8b-promoter is located at -45 to -40 base pairs (CCGCCC) from the transcriptional initiation site. Elimination of this element, by deletion or specific point mutation, significantly reduced transcriptional activity from this promoter. The sequence of this core region corresponds to a GC box motif known to act as a binding site for a ubiquitously expressed transcriptional activator, Sp1. However, the promoter activity appeared to be T-cell-specific, and the gel retardation assay using the core sequence as a probe revealed formation of complexes with multiple nuclear factors, one of them being specific to T lineage cells. These data suggest that the CD8b promoter requires a cis-acting element as well as several nuclear factors for full-range, tissue-specific transcription.
Kawachi
Y
Y
Department of Dermatology, The Institute of Clinical Medicine, University of Tsukuba 1-1-1, Ten-nodai, Tsukuba, Ibaraki 305, Japan.
Otsuka
F
F
Nakauchi
H
H
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D016827:CD8 Antigens / Q000235:genetics*; D002460:Cell Line; D004742:Enhancer Elements, Genetic; D005796:Genes; D007739:L Cells; D051379:Mice / Q000235:genetics*; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D016329:Sp1 Transcription Factor / Q000235:genetics; D014158:Transcription, Genetic
D016827:CD8 Antigens; D011993:Recombinant Fusion Proteins; D016329:Sp1 Transcription Factor