Early B-cell factor, E2A, and Pax-5 cooperate to activate the early B cell-specific mb-1 promoter.
Mol Cell Biol
; 22(24): 8539-51, 2002 Dec.
Article
em En
| MEDLINE
| ID: mdl-12446773
ABSTRACT
Previous studies have suggested that the early-B-cell-specific mb-1(Igalpha) promoter is regulated by EBF and Pax-5. Here, we used in vivo footprinting assays to detect occupation of binding sites in endogenous mb-1 promoters at various stages of B-cell differentiation. In addition to EBF and Pax-5 binding sites, we detected occupancy of a consensus binding site for E2A proteins (E box) in pre-B cells. EBF and E box sites are crucial for promoter function in transfected pre-B cells, and EBF and E2A proteins synergistically activated the promoter in transfected HeLa cells. Other data suggest that EBF and E box sites are less important for promoter function at later stages of differentiation, whereas binding sites for Pax-5 (and its Ets ternary complex partners) are required for promoter function in all mb-1-expressing cells. Using DNA microarrays, we found that expression of endogenous mb-1 transcripts correlates most closely with EBF expression and negatively with Id1, an inhibitor of E2A protein function, further linking regulation of the mb-1 gene with EBF and E2A. Together, our studies demonstrate the complexity of factors regulating tissue-specific transcription and support the concept that EBF, E2A, and Pax-5 cooperate to activate target genes in early B-cell development.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fatores de Transcrição
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Linfócitos B
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Receptores de Antígenos de Linfócitos B
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Antígenos CD
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Transativadores
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Regiões Promotoras Genéticas
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Proteínas de Ligação a DNA
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article