TY - JOUR
T1 - Sequence and evolution of the human T-cell antigen receptor β-chain genes
AU - Tunnacliffe, A.
AU - Kefford, R.
AU - Milstein, C.
AU - Forster, A.
AU - Rabbitts, T. H.
PY - 1985
Y1 - 1985
N2 - We present the nucleotide sequences of the two genomic constant (C)-region gene segments, C(β)1 and C(β)2, encoding the β chain of the human T-cell antigen receptor. The two C(β) genes are organized identically to each other and to the corresponding mouse genes, both having four exons, whose boundaries were confirmed from the sequence of a C(β)2 cDNA clone from the T-cell line MOLT-4. The predicted amino acid sequences of human C(β)1 and C(β)2 differ at only five positions, which suggests that the proteins have very similar functions. This similarity is the result of strong nucleotide-sequence conservation in protein-coding regions, which extends to silent positions. A quantitative analysis of an alignment of the nucleotide sequences of the two human genes shows that whereas the 5' ends (including the first exon) are extremely homologous, the 3' ends are widely divergent, with other regions having intermediate levels of homology. Analysis of published data [Gascoigne, N.R.J., Chien, Y., Becker, D.M., Kavaler, J. & Davis, M.M. (1984) Nature (London) 310, 387-391] shows that the mouse C(β)1 and C(β)2 genes are also virtually identical in their first exons but more divergent in the remaining coding regions. Therefore, partial gene conversion events may have occurred during the evolution of both human and mouse C(β) genes.
AB - We present the nucleotide sequences of the two genomic constant (C)-region gene segments, C(β)1 and C(β)2, encoding the β chain of the human T-cell antigen receptor. The two C(β) genes are organized identically to each other and to the corresponding mouse genes, both having four exons, whose boundaries were confirmed from the sequence of a C(β)2 cDNA clone from the T-cell line MOLT-4. The predicted amino acid sequences of human C(β)1 and C(β)2 differ at only five positions, which suggests that the proteins have very similar functions. This similarity is the result of strong nucleotide-sequence conservation in protein-coding regions, which extends to silent positions. A quantitative analysis of an alignment of the nucleotide sequences of the two human genes shows that whereas the 5' ends (including the first exon) are extremely homologous, the 3' ends are widely divergent, with other regions having intermediate levels of homology. Analysis of published data [Gascoigne, N.R.J., Chien, Y., Becker, D.M., Kavaler, J. & Davis, M.M. (1984) Nature (London) 310, 387-391] shows that the mouse C(β)1 and C(β)2 genes are also virtually identical in their first exons but more divergent in the remaining coding regions. Therefore, partial gene conversion events may have occurred during the evolution of both human and mouse C(β) genes.
UR - http://www.scopus.com/inward/record.url?scp=0022253055&partnerID=8YFLogxK
U2 - 10.1073/pnas.82.15.5068
DO - 10.1073/pnas.82.15.5068
M3 - Article
C2 - 3860845
AN - SCOPUS:0022253055
VL - 82
SP - 5068
EP - 5072
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 15
ER -