Cloning and functional characterization of LCR-F1: a bZIP transcription factor that activates erythroid-specific, human globin gene expression.
DNase I hypersensitive site 2 (HS 2) of the human beta-globin Locus Control Region (LCR) directs high level expression of the beta-globin gene located 50 kilobases downstream. Experiments in cultured cells and in transgenic mice demonstrate that duplicated AP1-like sites in HS 2 are required for this powerful enhancer activity. A cDNA clone encoding a basic, leucine-zipper protein that binds to these sites was isolated and designated Locus Control Region-Factor 1 (LCR-F1). This protein is a member of a new family of regulatory factors that contain a 63 amino acid 'CNC domain' overlapping the basic region. This domain is approximately 70% identical in the Drosophila Cap N Collar (CNC) protein, NF-E2 and LCR-F1. LCR-F1 transactivates an HS 2/gamma-globin reporter gene over 170-fold in transient transfection experiments specifically in erythroid cells. These results suggest that LCR-F1 may be a critical factor involved in LCR-mediated, human globin gene expression.
Department of Biochemistry and Molecular Genetics, School of Medicine, University of Alabama at Birmingham 35294.
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Caterina
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Donze
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Sun
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Ciavatta
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Townes
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D004247:DNA; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D005786:Gene Expression Regulation; D005914:Globins / Q000096:biosynthesis / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009154:Mutation; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; D051265:NF-E2-Related Factor 1; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; D051265:NF-E2-Related Factor 1; C494692:NFE2 protein, human; C088357:NFE2L1 protein, human; C494693:Nfe2 protein, mouse; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D005914:Globins; D004247:DNA