The promoter of the CD19 gene is a target for the B-cell-specific transcription factor BSAP.
The CD19 protein is expressed on the surface of all B-lymphoid cells with the exception of terminally differentiated plasma cells and has been implicated as a signal-transducing receptor in the control of proliferation and differentiation. Here we demonstrate complete correlation between the expression pattern of the CD19 gene and the B-cell-specific transcription factor BSAP in a large panel of B-lymphoid cell lines. The human CD19 gene has been cloned, and several BSAP-binding sites have been mapped by in vitro protein-DNA binding studies. In particular, a high-affinity BSAP-binding site instead of a TATA sequence is located in the -30 promoter region upstream of a cluster of heterogeneous transcription start sites. Moreover, this site is occupied by BSAP in vivo in a CD19-expressing B-cell line but not in plasma or HeLa cells. This high-affinity site has been conserved in the promoters of both human and mouse CD19 genes and was furthermore shown to confer B-cell specificity to a beta-globin reporter gene in transient transfection experiments. In addition, BSAP was found to be the only abundant DNA-binding activity of B-cell nuclear extracts that interacts with the CD19 promoter. Together, this evidence strongly implicates BSAP in the regulation of the CD19 gene.
Kozmik
Z
Z
Institute of Molecular Pathology, Vienna, Austria.
Wang
S
S
Dörfler
P
P
Adams
B
B
Busslinger
M
M
D000818:Animals; D015703:Antigens, CD / Q000235:genetics*; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte / Q000235:genetics*; D001402:B-Lymphocytes / Q000502:physiology*; D001483:Base Sequence; D005075:Biological Evolution; D004268:DNA-Binding Proteins / Q000502:physiology*; D005786:Gene Expression Regulation; D005796:Genes; D006801:Humans; D007438:Introns; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000502:physiology*; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D051757:PAX5 Transcription Factor; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid; D016415:Sequence Alignment; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D015703:Antigens, CD; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D009838:Oligodeoxyribonucleotides; D051757:PAX5 Transcription Factor; C497281:PAX5 protein, human; C497282:Pax5 protein, mouse; D012333:RNA, Messenger; D014157:Transcription Factors