CD3- T cells with cis- or trans-acting mutations affecting expression of T cell receptor beta-chain mRNA.
Mutants of an untransformed T cell clone that no longer respond to TCR/CD3 stimulation have been derived using a selection procedure based on the loss of functional response to Ag. This functional selection gives rise to clones of several different phenotypes. We have previously described mutants with a TCR/CD3+ cell surface phenotype whose TCR are uncoupled from cellular responses. We describe six additional mutants that do not express TCR/CD3 at the cell surface. One of the CD3- clones contains a deletion in the successfully rearranged TCR-alpha gene, whereas another carries a deletion in the successfully rearranged TCR-beta gene. TCR/CD3 expression in these deletion mutants can be restored by transfection of TCR-alpha or TCR-beta DNA. Four other clones do not express TCR-beta mRNA, yet contain no obvious deletions or rearrangements in the TCR-beta genes. One of these clones does not transcribe TCR-beta chain mRNA. The mutation in this clone does not reside in the TCR-beta gene itself, but may instead reside in a trans-acting regulatory element affecting TCR-beta gene expression, because the TCR-beta mRNA-phenotype is complemented by fusion with a TCR-alpha-beta- cell line. TCR-beta chain regulatory mutants will be valuable in contributing to our understanding of how TCR expression is regulated.
Wong
J G
JG
Division of Tumour Virology, Dana-Farber Cancer Institute, Boston, MA 02115.
Kasibhatla
S
S
Nalefski
E A
EA
Rao
A
A
D000818:Animals; D015152:Blotting, Northern; D017252:CD3 Complex / Q000276:immunology*; D002999:Clone Cells; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000235:genetics*; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor / Q000502:physiology; D007376:Interleukin-2 / Q000096:biosynthesis; D009115:Muridae; D012333:RNA, Messenger / Q000096:biosynthesis*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis* / Q000235:genetics*; D013601:T-Lymphocytes / Q000276:immunology*; D014158:Transcription, Genetic
D017252:CD3 Complex; D007376:Interleukin-2; D012333:RNA, Messenger; D016693:Receptors, Antigen, T-Cell, alpha-beta