The role of short homology repeats and TdT in generation of the invariant γδ antigen receptor repertoire in the fetal thymus

Yi Zhang, Dragana Cado, David M. Asarnow, Toshihisa Komori, Frederick W. Alt, David H. Raulet, James P. Allison

Research output: Contribution to journalArticle

45 Scopus citations


Fetal thymic and adult epithelial Vγ3+ and Vγ4+ T cells express γδ antigen receptors (TCR) with invariant junctions lacking N nucleotides. Using transgenic recombination substrates, we show that di- or trinucleotide repeats, either in the coding region or in P elements, have strong effects on the site of recombination. In other mice bearing a terminal deoxynucleotidyl transferase (TdT) transgene under the control of the CD2 promoter, we found that the frequency of canonical junctions was markedly reduced with a concomitant increase in in-frame noncanonical junctions with N nucleotides. Together, our results show that short homology repeats direct the site of rearrangement and thus play a critical role in the generation of γδ T cell receptor canonical junctions. Increased TdT activity in Vγ3+ T cells has a inhibitory effect on junctional homogeneity in these cells.

Original languageEnglish (US)
Pages (from-to)439-447
Number of pages9
Issue number4
StatePublished - Oct 1995


ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology
  • Infectious Diseases

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