TY - JOUR
T1 - A functional γ gene formed from known γ-gene segments is not necessary for antigen-specific responses of murine cytotoxic T lymphocytes
AU - Reilly, E. B.
AU - Kranz, D. M.
AU - Tonegawa, S.
AU - Eisen, H. N.
PY - 1986
Y1 - 1986
N2 - Structural similarities between surface immunoglobulins (s Ig) on B cells and antigen-specific receptors on T cells suggest that a T cell, like a B cell, should express only two immunoglobulin-like genes, one for each subunit of the disulphide-linked, heterodimeric, antigen-specific (αβ) T-cell receptor. However, cytotoxic T lymphocytes (Tc cells) and immature thymocytes also contain RNA transcripts of a third immunoglobulin-like gene, called γ (refs 1-4). A polypeptide corresponding to the γ gene has not yet been identified and the function of this gene remains an enigma. Judging from its nucleotide sequence, the rearranged γ gene is expected to encode an integral membrane polypeptide chain, and γ complementary DNAs from two cloned Tc cell lines have previously been found to have different sequences around the V-J (variable region-joining region) junction 1,2, suggesting that, in these cells, the γ-gene product is a clonally diverse surface structure that may form part of an as yet unidentified, antigen-specific receptor. To analyse further the extent of diversity of the γ-gene product, we have determined the partial sequences of 11 γ cDNA clones from three other cloned Tc cell lines, and report here that the sequences are indeed clonally diverse, but in all instances they are out-of-phase in the region of the V-J junction. This finding and the pattern of γ-gene rearrangements in these cell lines indicate that a polypeptide product of the previously reported γ gene, V2J2-C2, is not expressed in them and is, therefore, not necessary for the antigen-specific cytotoxic and proliferative responses of these mature T cells.
AB - Structural similarities between surface immunoglobulins (s Ig) on B cells and antigen-specific receptors on T cells suggest that a T cell, like a B cell, should express only two immunoglobulin-like genes, one for each subunit of the disulphide-linked, heterodimeric, antigen-specific (αβ) T-cell receptor. However, cytotoxic T lymphocytes (Tc cells) and immature thymocytes also contain RNA transcripts of a third immunoglobulin-like gene, called γ (refs 1-4). A polypeptide corresponding to the γ gene has not yet been identified and the function of this gene remains an enigma. Judging from its nucleotide sequence, the rearranged γ gene is expected to encode an integral membrane polypeptide chain, and γ complementary DNAs from two cloned Tc cell lines have previously been found to have different sequences around the V-J (variable region-joining region) junction 1,2, suggesting that, in these cells, the γ-gene product is a clonally diverse surface structure that may form part of an as yet unidentified, antigen-specific receptor. To analyse further the extent of diversity of the γ-gene product, we have determined the partial sequences of 11 γ cDNA clones from three other cloned Tc cell lines, and report here that the sequences are indeed clonally diverse, but in all instances they are out-of-phase in the region of the V-J junction. This finding and the pattern of γ-gene rearrangements in these cell lines indicate that a polypeptide product of the previously reported γ gene, V2J2-C2, is not expressed in them and is, therefore, not necessary for the antigen-specific cytotoxic and proliferative responses of these mature T cells.
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U2 - 10.1038/321878a0
DO - 10.1038/321878a0
M3 - Article
C2 - 3487735
AN - SCOPUS:0022655571
SN - 0028-0836
VL - 321
SP - 878
EP - 880
JO - Nature
JF - Nature
IS - 6073
ER -