Characterization of promoter elements of an interferon-inducible Ly-6E/A differentiation antigen, which is expressed on activated T cells and hematopoietic stem cells.
The Ly-6E/A antigen is expressed on activated murine T cells. Using probes made from the previously characterized cDNA, we have isolated a genomic DNA clone encoding the Ly-6A antigen. We determined the DNA sequence of the genomic clone and conducted a functional analysis of the promoter region. Mouse fibroblast BALB/3T3 cells transfected with this genomic clone constitutively expressed Ly-6A antigen on their cell surface. This expression was inducible by alpha/beta and gamma interferons. The Ly-6E 5'-flanking region was analyzed by chloramphenicol acetyltransferase assays in fibroblast cells for cis-acting elements. At least two positive elements were found to be needed for maximum constitutive promoter activity in L cells. One of the positive elements was specifically bound by a CCAAT box-binding protein from crude nuclear extract, as shown by electrophoretic mobility shift assays and footprinting. The other element, which contains a GGAAA motif and has homology to various known enhancers, also showed a specific binding activity. This second positive element when multimerized became a very powerful enhancing element. Interferon treatment could enhance expression of the chloramphenicol acetyltransferase gene fused to the Ly-6E 5'-flanking region in stably transfected BALB/3T3 cells. The elements responsible for this enhancement lie, at least in part, between positions -1760 and -900 of the gene. Surprisingly, there is no sequence homology between this region of Ly-6E and the established consensus for the interferon-stimulated response element, which has been shown functionally important to all previously characterized alpha/beta interferon-inducible promoters. The Ly-6E gene may prove to be a novel system for the study of interferon induction.
Khan
K D
KD
Department of Biology, Yale University Medical School, New Haven, Connecticut 06510.
Lindwall
G
G
Maher
S E
SE
Bothwell
A L
AL
D000595:Amino Acid Sequence; D000818:Animals; D000950:Antigens, Ly / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects; D005796:Genes; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D007372:Interferons / Q000494:pharmacology; D007739:L Cells; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013601:T-Lymphocytes / Q000502:physiology*; D014162:Transfection
D000950:Antigens, Ly; D004268:DNA-Binding Proteins; D007372:Interferons