TCR beta and TCR alpha gene enhancers confer tissue‐ and stage‐specificity on V(D)J recombination events.

We describe transgenic mice carrying germline variable gene segments associated with either the T cell receptor (TCR) beta or alpha gene enhancers (E beta or E alpha). Transgenic constructs underwent high rates of site‐specific rearrangements predominantly in T cells from independent mice. Rearrangements of the E beta‐containing transgenes began at different stages of T cell differentiation in embryonic and adult thymus than did the E alpha‐containing ones, with a pattern superimposable upon the patterns of TCR beta or TCR alpha gene expression, respectively. We demonstrate that sequences within the TCR beta and TCR alpha gene enhancers confer tissue‐ and stage‐specificity upon the V(D)J recombination events affecting adjacent gene segments. The patterns of transgene expression also gave information on developmental events and lineage relationships (gamma delta versus alpha beta) during T cell development.