Abstract
T cell receptor (TCR) and B cell receptors (BCR) junctions, also known as the CDR3, are where the V, D, and J gene segments converge, coding for a loop structure important for contacting ligands. J segments contribute to the formation of the CDR3 loop through their 5′ ends that vary in length and show high sequence variability. The 5′ ends of J segments of TCRα genes show nucleotide sequence similarities to TCRDδ segments as high as 89% and show a preponderance of murine TCRDδ2 or human TCRDδ3 amino acid sequence similarities. Surprisingly, most of the 5′ ends of TCRJγ segments show nucleotide and amino acid sequence similarities with TCRDβ segments. All murine and human BCRJH segments and most TCRJδ segments contain amino acid sequences at their 5′ ends that resemble their own D segments, a finding that is not seen with TCRJβ segments. TCRα and TCRγ genes thus make up for their lack of separate D segments with distinct D-like segments that are built into the 5′ ends of their J segments. Additionally, in some cases, TCR and BCR genes that utilize separate D segments also receive additional D-like contributions though the 5′ ends of their J segments to add additional diversity to their CDR3 loops.
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References
Alt FW, Oltz EM, Young F, Gorman J, Taccioli G, Chen J (1992) VDJ recombination. Immunol Today 13:306–314
Arden B, Clark MP, Kabelitz D, Mak TW (1995) Mouse T-cell receptor variable gene segment families. Immunogenetics 42:501–530
Chothia C, Lesk AM (1987) Canonical structures for the hypervariable regions of immunoglobulins. J Mol Biol 186:901–917
Chothia C, Boswell DR, Lesk AM (1988) The outline structure of the T-cell αβ receptor. EMBO J 7:3745–3755
Criscitiello MF, Saltis M, Flajnik MF (2006) An evolutionarily mobile antigen receptor variable region gene: double rearranging NAR-TcR genes in sharks. Proc Natl Acad Sci 103:5036–5041
Davies DR, Padllan EA, Sheriff S (1990) Antibody-antigen complexes. Ann Rev Biochem 59:439–473
Engel I, Henrick SM (1988) Site-directed mutations in the VDJ junctional region of a T-cell receptor beta chain cause changes in antigenic peptide recognition. Cell 54:473–484
Fellah JS, Kerfourn F, Dumay AM, Aubet G, Charlemagne J (1997) Structure and diversity of the T-cell receptor alpha chain in the Mexican axolotl. Immunogenetics 45:235–241
Koop BF, Rowen L, Wang K, Kuo CL, Seto D, Lenstra JA, Howard S, Shan W, Deshpande P, Hood L (1994) Genomics 19:478–493 The human T-cell receptor TCRAC/TCRDC (C alpha/C delta) region: organization, sequence, and evolution of 97.6 kb of DNA
Pattern P, Yokota T, Rothbard J, Chien Y, Arai K, Davis MM (1984) Structure, expression, and divergence of T-cell receptor beta-chain variable regions. Nature 312:40–46
Raulet DH (1989) The structure, function, and molecular genetics of the γ/δ T cell receptor. Annu Rev Immunol 7:175–207
Reardon CL, Hu L-J, Yin X, Born WK, Arden B, O'Brien RL (2007) A new mechanism for generating TCR diversity: a TCR Jα-like gene that inserts partial nucleotide sequences in a D-gene manner. Mol Immunol 44:906–915
Rock EP, Sibbald PR, Davis MM, Chien Y-H (1994) CDR3 length in antigen-specific immune receptors. J Exp Med 179:323–328
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Much thanks go to Rebecca O'Brien and Willi K. Born for their reviews of this manuscript and their helpful suggestions. The manuscript is the result of work supported with resources and the use of facilities through the Phoenix VA Health Care System. The contents do not represent the views of the Department of Veterans Affairs or the United States Government.
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Reardon, C.L. TCRJ and BCRJ gene segments contain 5′ D-segment sequences that contribute to repertoire diversity. Immunogenetics 61, 673–687 (2009). https://doi.org/10.1007/s00251-009-0388-5
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DOI: https://doi.org/10.1007/s00251-009-0388-5