title: Structure, expression and divergence of T-cell receptor beta-chain variable regions.
abstract: Analysis of three new T-cell receptor beta-chain variable regions together with those in the literature indicates that they have both remarkable similarities and differences with those of immunoglobulin. Less than 10 V regions appear to predominate in the thymus. V beta sequences are much more heterogeneous at the amino acid level than are immunoglobulin V regions and they appear to diverge between species much more quickly, apparently the result of additional hypervariable regions. Three of these putative new hypervariable regions lie outside of the classical immunoglobulin binding site, an indication that important interactions may be occurring in these regions with polymorphic MHC determinants.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D004262:DNA Restriction Enzymes; D005796:Genes; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D007136:Immunoglobulins / Q000235:genetics; D046911:Macromolecular Substances; D008285:Major Histocompatibility Complex; D051379:Mice; D008807:Mice, Inbred BALB C; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D007135:Immunoglobulin Variable Region; D007136:Immunoglobulins; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell; D004262:DNA Restriction Enzymes