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Lineage-specific expression of a T cell receptor variable gene promoter controlled by upstream sequences.

1989; Rockefeller University Press; Volume: 169; Issue: 4 Linguagem: Inglês

10.1084/jem.169.4.1213

1540-9538

Don J. Diamond, Forrest B. Nelson, Ellis L. Reinherz,

Monoclonal and Polyclonal Antibodies Research

We have characterized the sequence contribution of DNA 5' of a functionally rearranged TCR promoter (V beta 8.1) on its T lineage-specific expression through the use of the chloramphenicol acetyl-transferase (CAT) reporter gene. A 230-bp fragment located 570 bp upstream of the determined transcription start site of the V beta 8.1 promoter confers a T lineage specificity of expression to a heterologous promoter. The inability of the V beta 8.1 promoter and its associated elements to function in B cells suggests the existence of a mechanism to prevent inappropriate V beta gene expression in B cells. Of considerable interest is the fact that both a B cell-specific and a nontissue-specific enhancer element were incapable of stimulating significant expression of this promoter in B cells. We discuss the implication of these results on the process of rearrangement of both Ig and TCR genes, and the differentiation of the lymphoid system.