The genomic structure and promoter analysis of the human ABF-1 gene.
The human ABF-1 gene is expressed in activated B-cells and Epstein-Barr virus-immortalized lymphoblastoid cell lines. ABF-1 represents the only member belonging to the basic helix-loop-helix (bHLH) family of transcription factors whose expression pattern is restricted to B-cells. ABF-1 forms heterodimeric complexes with E2A to modulate gene transcription. We report the cloning and characterization of the human ABF-1 gene and the promoter region. The gene spans more than 3 kb and contains two exons. Exon 1 contains 274 bp of a 5'-untranslated sequence (UTR) while exon 2 contains 1097 bp of 3'-UTR. Promoter analysis of the 5'-flanking region revealed no apparent B-cell-restricted control elements within approximately 700 bp, but clearly demonstrated the presence of a functional minimal promoter residing immediately upstream of the transcription start site. Analysis of the region containing the minimal promoter activity identified no CCAAT or TATA sequence. Lastly, we have assigned the ABF-1 gene to human chromosome 8q21.1 using fluorescence in situ hybridization (FISH). The cloning of the human ABF-1 gene will facilitate further biochemical and genetic studies of its function in the regulation of B-cell differentiation.
Mitchell
B
B
Department of Biology, University of the Pacific, Stockton, CA 95211, USA.
Mugiya
M
M
Youngblom
J
J
Funes-Duran
M
M
Miller
R
R
Ezpeleta
J
J
Rigby
N
N
Vierra
C
C
D001483:Base Sequence; D002874:Chromosome Mapping; D002898:Chromosomes, Human, Pair 8; D004247:DNA / Q000032:analysis; D004268:DNA-Binding Proteins / Q000235:genetics*; D015894:Genome, Human; D015698:Genomic Library; D006801:Humans; D007621:Karyotyping; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins; D016385:TATA Box; D014157:Transcription Factors / Q000235:genetics*; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured
C061886:ABF1 protein, S cerevisiae; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D004247:DNA