T early alpha (TEA) regulates initial TCRVAJA rearrangements and leads to TCRJA coincidence.
Both TCRA alleles are rearranged in mature T lymphocytes, as a result of a lack of allelic exclusion at the TRCA locus. We show in a series of T cell clones that the two TCRJA segments are not randomly, but rather coincidentally, rearranged in a given T cell. The TCRJA coincidence relies, in part, on the presence of "T early alpha" (TEA), a cis-regulatory genetic element located upstream of the TCRJA cluster. TEA promotes specific recombinational accessibility that targets primary TCRVAJA rearrangements on the 5' side of the TCRA locus. In a model of multiple waves of TCRVAJA recombination, this cis-regulatory effect of TEA allows for the scanning of the entire TCRJA cluster, thereby increasing the TCR alpha/beta diversity potential.
Mauvieux
L
L
Développement Normal et Pathologique du Système Immunitaire, INSERM U429, France.
Villey
I
I
de Villartay
J P
JP
D020121:5' Untranslated Regions; D000818:Animals; D002999:Clone Cells; D015332:Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor; D006825:Hybridomas; D007133:Immunoglobulin Joining Region / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008957:Models, Genetic; D020218:Response Elements; D013601:T-Lymphocytes / Q000276:immunology*
D020121:5' Untranslated Regions; D007133:Immunoglobulin Joining Region; D007135:Immunoglobulin Variable Region