title: Complexity of human T-cell antigen receptor beta-chain constant- and variable-region genes.
abstract: Immune systems of vertebrates function via two types of effector cells, B and T cells, which are capable of antigen-specific recognition. The immunoglobulins, which serve as antigen receptors on B cells, have been well characterized with respect to gene structure, unlike the T-cell receptors. Recently, cDNA clones thought to correspond to the beta-chain locus of the human and mouse T-cell receptor have been described. The presumptive beta-chain clones detect gene rearrangement specifically in T-cell DNA and show homology with immunoglobulin light chains. The similarity of the T-cell beta-chain gene system to the immunoglobulin genes has been further demonstrated by the recent observation of variable- and constant-region gene segments as well as joining segments and putative diversity segments. We report here the characterization of cDNA and genomic clones encoding human T-cell receptor beta-chain genes. There are two constant-region genes (C beta 1 and C beta 2), each capable of rearrangement and expression as RNA. The gene arrangement, analogous to that of mouse beta-chain genes, shows strong evolutionary conservation of the dual C beta gene system in these two species.
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D002460:Cell Line; D005796:Genes; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D011995:Recombination, Genetic; D013601:T-Lymphocytes / Q000502:physiology*
chemical_list: D007136:Immunoglobulins; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell