Sequence Analysis of the Mouse RAG Locus lntergenic Region

The recombination activating genes RAG-1 and RAG-2 are highly conserved throughoutevolution and are necessary and essential for the DNA rearrangement of antigen-receptor genesegments. These convergently transcribed genes are expressed primarily by developing B and Tlineage cells. In addition, recent data suggest that the RAG locus can be reactivated in mousegerminal center B cells. Despite these well-defined patterns of expression, little is known aboutmechanism(s) regulating transcription of the RAG locus. Experiments with a mouse fibroblastline stably transfected with a genomic fragment of the RAG locus suggest that the intergenicregion between RAG-1 and RAG-2 may contain information modulating RAG transcription. Inorder to begin testing this hypothesis, we have sequenced the 7.0-kb RAG intergenic region ofthe mouse. The sequence did not contain open reading frames larger than 60 amino acids.Analysis with GCG software identified several potential transcription-factor binding sequenceswithin this region. Many of these are associated with transcriptional regulation of the Ig locus.Peer Reviewe