Characterization of a new functional TCR J delta segment in humans. Evidence for a marked conservation of J delta sequences between humans, mice, and sheep.
Through analysis of TCR delta-chain cDNA derived from human gamma delta T cell clones and polyclonal gamma delta T cell lines, we isolated a novel functional J delta gene segment (termed J delta 4) whose genomic fragment has been mapped within the TCR-delta locus between J delta 2 and J delta 1. Frequency of J delta 4 use was estimated among adult gamma delta PBL by using V delta 1, V delta 2, and V delta 5 genes. In all cases, this new J element was used at a low, albeit significant frequency, close to that of J delta 2. Finally, like human J delta 1 and J delta 2, which show a high degree of homology with their counterparts in the mouse and sheep, but unlike other J gamma, J beta, or J alpha elements, J delta 4 turned out to be highly homologous to a recently described ovine J delta. These results suggest the existence of strong selective pressures, possibly linked to an Ag-driven process, leading to specific conservation of J delta sequences among these three species.
Davodeau
F
F
INSERM U211, Biology Institute, Nantes, France.
Peyrat
M A
MA
Hallet
M M
MM
Vié
H
H
Bonneville
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D016694:Gene Rearrangement, delta-Chain T-Cell Antigen Receptor; D005796:Genes; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes / Q000737:chemistry; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics*; D015183:Restriction Mapping; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012756:Sheep
D015345:Oligonucleotide Probes; D016692:Receptors, Antigen, T-Cell, gamma-delta