Figure 4. Transcription on the Jβ1^σ allele during development.

A. Northern blot analyses of thymocytes from Rag-2^-/- mice with a wild type TCRβ locus (WT:Rag-2^-/-) and from Jβ1^ω/ω:Rag-2^-/- and Jβ1^σ/σ:Rag-2^-/- mice using probe D (see Fig. 3D). The relative level of probe D hybridizing germline Dβ1-Jβ1 transcripts in each lane is indicated, normalized to β-actin expression. B. Northern blot analyses of splenocytes from Jβ1^ω/ω and Jβ1^σ/σ mice using probes to the Cβ and Cα constant region genes. The relative level of Cβ and Cα hybridizing mature transcripts is indicated, normalized to β-actin expression. C. Flow cytometric analyses showing TCRβ expression on Thy1 expressing (T cells) Jβ1^ω/ω and Jβ1^σ/σ splenocytes.