Recombinase activating gene expression in thymic subpopulations. A transitional cell type has lost RAG-2 but not RAG-1.
We have used a highly sensitive Northern blot probing technique to examine RAG-1 and RAG-2 mRNA expression in unmanipulated murine thymocytes of various developmental phenotypes sorted by flow cytometry. We have found that neither RAG-1 nor RAG-2 are down-regulated until thymocytes reach the TCRhi stage. TCRhi, CD8+CD4+ cells have lost RAG-2 mRNA but continue to express significant levels of RAG-1 mRNA, providing molecular evidence that this cell type is transitional between the TCRlo, CD4+CD8+ and the TCRhi, CD4+CD8-, or CD4-CD8+ phenotypes.
Campbell
J J
JJ
University of Pennsylvania, School of Medicine, Department of Pathology, Philadelphia 19104.
Hashimoto
Y
Y
D000818:Animals; D001483:Base Sequence; D004268:DNA-Binding Proteins; D005434:Flow Cytometry; D015870:Gene Expression; D015329:Gene Rearrangement, T-Lymphocyte; D018398:Homeodomain Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D011995:Recombination, Genetic; D013950:Thymus Gland / Q000166:cytology* / Q000254:growth & development; D001613:beta 2-Microglobulin / Q000235:genetics
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D009838:Oligodeoxyribonucleotides; D011506:Proteins; D012333:RNA, Messenger; C499308:Rag2 protein, mouse; D011948:Receptors, Antigen, T-Cell; C064655:V(D)J recombination activating protein 2; D001613:beta 2-Microglobulin; C064658:RAG-1 protein