In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 95, No. 25 ( 1998-12-08), p. 14909-14914
Abstract:
T cell antigen receptor (TCR) and pre-TCR complexes are composed of clonotypic heterodimers in association with dimers of signal transducing invariant subunits (CD3γ, -δ, -ɛ, and ζ). The role of individual invariant subunits in T cell development has been investigated by generating gene-specific mutations in mice. Mutation of CD3γ, -δ, or ζ results in an incomplete block in development, characterized by reduced numbers of mature T cells that express low levels of TCR. In contrast, mature T cells are absent from CD3ɛ −/− mice, and thymocyte development is arrested at the early CD4 − CD8 − stage. Although these results suggest that CD3ɛ is essential for pre-TCR and TCR expression/function, their interpretation is complicated by the fact that expression of the CD3γ and CD3δ genes also is reduced in CD3ɛ −/− mice. Thus, it is unclear whether the phenotype of CD3ɛ −/− mice reflects the collective effects of CD3γ, -δ, and -ɛ deficiency. By removing the selectable marker (PGK-NEO) from the targeted CD3ɛ gene via Cre/ lox P-mediated recombination, we generated mice that lack CD3ɛ yet retain normal expression of the closely linked CD3γ and CD3δ genes. These (CD3ɛ Δ/Δ ) mice exhibited an early arrest in T cell development, similar to that of CD3ɛ −/− mice. Moreover, the developmental defect could be rescued by expression of a CD3ɛ transgene. These results identify an essential role for CD3ɛ in T cell development not shared by the CD3γ, CD3δ, or ζ-family proteins and provide further evidence that PGK-NEO can influence the expression of genes in its proximity.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.95.25.14909
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
1998
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
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