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Prototypic T cell receptor and CD4-like coreceptor are expressed by lymphocytes in the agnathan sea lamprey.

ABSTRACT: All jawed vertebrates have highly diverse lymphocyte receptors, which allow discrimination between self and nonself antigens as well as the recognition of potential pathogens. Key elements of the anticipatory recombinatorial immune system in jawed vertebrates are the TCR, Ig, and MHC genes, but their ancestral genes have not been found in more basal vertebrates. In this study, we extended our analysis of the transcriptome of lymphocyte-like cells in the lamprey to identify the TCR-like and CD4-like genes. The structural features of these genes and their preferential expression in lymphocytes make them attractive candidates for ancestral TCR and CD4 genes. The TCR-like gene contains both V (variable) and J (joining) sequences in its first exon and exists as a single-copy gene that is invariant. Thus, the TCR-like gene cannot account for the receptor diversity that is required for the immune responses reported for lamprey, but it could have been easily modified to serve as an evolutionary precursor of modern TCR and Ig genes.

SUBMITTER: Pancer Z

PROVIDER: S-EPMC516559 | biostudies-literature | 2004 Sep

REPOSITORIES: biostudies-literature

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Prototypic T cell receptor and CD4-like coreceptor are expressed by lymphocytes in the agnathan sea lamprey.

Pancer Zeev Z Mayer Werner E WE Klein Jan J Cooper Max D MD

Proceedings of the National Academy of Sciences of the United States of America 20040824 36

All jawed vertebrates have highly diverse lymphocyte receptors, which allow discrimination between self and nonself antigens as well as the recognition of potential pathogens. Key elements of the anticipatory recombinatorial immune system in jawed vertebrates are the TCR, Ig, and MHC genes, but their ancestral genes have not been found in more basal vertebrates. In this study, we extended our analysis of the transcriptome of lymphocyte-like cells in the lamprey to identify the TCR-like and CD4-l ...[more]

PMID: 15328402

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Dataset Information

Prototypic T cell receptor and CD4-like coreceptor are expressed by lymphocytes in the agnathan sea lamprey.

Publications

Prototypic T cell receptor and CD4-like coreceptor are expressed by lymphocytes in the agnathan sea lamprey.

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