Diversity of T cell receptor delta-chain cDNA in the thymus of a one-month-old pig.
Pig TCR delta-chain cDNA sequences were obtained from the anchored PCR products of the reverse-transcribed RNA from the thymus of a 1-mo-old germfree pig. Among 43 sequences analyzed, 4 different J delta sequences were found, and in the cDNA sequences of rearranged V-D-J junctional regions, three putative D delta sequences were assigned. Also, the V delta region sequences were grouped into five families. One family, V delta 1, consisted of a large number of members and the other families consisted of limited members as determined by cDNA sequences as well as genomic Southern blots. Using PCR, V delta 1 gene segments were also obtained from liver genomic DNA of the same individual pig. Thirty-one distinct sequences were found for the V delta 1 family including the sequences obtained from both the thymic RNA and the PCR product of liver DNA. All the V delta 1 genes were found to be associated with almost identical leader gene sequences. The amino acid sequences of the complimentarity-determining region 3 coded by the V-D-J joints gave long and variable lengths with a high content of tryptophan and charged amino acids. The length of the complimentarity-determining region 3 in the porcine TCR delta-chain supports the idea that TCR delta-chain is designed to see Ags directly similar to the Ig heavy chain. Data presented from this study shows that the porcine TCR delta-chain has extensive V region diversity as well as junctional diversity. The combination of these two creates a level of diversity that is the highest of any lymphocyte Ag receptor studied so far.
Yang
Y G
YG
Department of Immunology, Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan.
Ohta
S
S
Yamada
S
S
Shimizu
M
M
Takagaki
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000737:chemistry*; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D021382:Protein Sorting Signals / Q000235:genetics; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000737:chemistry / Q000235:genetics*; D013552:Swine / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology*
D018076:DNA, Complementary; D021382:Protein Sorting Signals; D016692:Receptors, Antigen, T-Cell, gamma-delta