Extrathymic positive selection of gamma delta T cells. V gamma 4J gamma 1 rearrangements with "GxYS" junctions.
Neither function nor Ag recognition properties of gamma delta T cells are well understood yet. A TCR gamma-chain family, characterized by distinct N region sequences that converge in coding for a "GxYS" VJ junctional sequence, appears late in ontogeny among highly diversified V gamma 4J gamma 1C gamma 1 chains of C57BL/6 and BALB/c mice. The glycine and serine codons are of germline V gamma 4 and J gamma 1 origin, respectively, whereas the N region consists of a variable amino acid residue x, followed by an invariant tyrosine Y. The high expression of V gamma 4 xYJ gamma 1C gamma 1 in the lung of BALB/c mice compared to that of C57BL/6 is apparently due to a novel pattern of strain-dependent positive selection which, unlike for alpha beta TCR, operates extrathymically. This type of selection seems to be determined by strain specific polymorphic ligands encoded outside of the classical H-2 region.
Sim
G K
GK
Basel Institute for Immunology, Switzerland.
Augustin
A
A
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D008168:Lung / Q000166:cytology; D051379:Mice; D008815:Mice, Inbred Strains; D008819:Mice, Nude / Q000235:genetics; D008969:Molecular Sequence Data; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013601:T-Lymphocytes / Q000502:physiology*; D013950:Thymus Gland / Q000166:cytology / Q000196:embryology
D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta