A role for the cytoplasmic tail of the beta chain of CD8 in thymic selection.
The CD8 coreceptor plays a critical role in the recognition of foreign antigens by mature T cells and in the development of class I-restricted T cells. CD8 can be expressed on the surface of T cells as either a heterodimer composed of an alpha and beta chain, or as a homodimer composed of two alpha chains. In this report, we show that a CD8 beta transgene that lacks a cytoplasmic domain can suppress expression of wild-type endogenous CD8 beta and act as a dominant negative mutation. We show that this dominant negative CD8 beta transgene interferes with the development of mature CD8 T cells to different extents depending on the individual class I-restricted TCR. These data suggest CD8 beta plays a role in thymic development, and that different class I-restricted TCRs differ in their dependence on the cytoplasmic tail of CD8 beta.
Itano
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A
Department of Molecular and Cell Biology, University of California, Berkeley 94720.
Cado
D
D
Chan
F K
FK
Robey
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E
D000818:Animals; D001483:Base Sequence; D016827:CD8 Antigens / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation; D003593:Cytoplasm / Q000276:immunology; D004247:DNA / Q000235:genetics; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009154:Mutation; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*
D016827:CD8 Antigens; D015395:Histocompatibility Antigens Class I; D011948:Receptors, Antigen, T-Cell; D004247:DNA