V(D)J recombination is regulated similarly in RAG-transfected fibroblasts and pre-B cells.
Here we compare the regulation of V(D)J recombination in the fibroblast cell line L4 and the pre-B cell line 38B9. The former has been rendered recombination-competent by stable transfection of a genomic fragment comprising the recombination activating genes, RAG-1 and RAG-2, along with some of their flanking sequences. We show that V(D)J recombination is similarly regulated in these two cell lines. Activating signals are transmitted through the protein kinase A (PKA) pathway, and inhibitory signals through the protein kinase C (PKC) and the calcium signalling pathways. In both cell lines, recombinational activity reflects steady state levels of mRNA transcribed from the RAG-1 and RAG-2 genes. This suggests that transcription of the RAG genes is a major determinant regulating V(D)J recombination. A comparison of RAG-1 and RAG-2 mRNA levels within each cell line reveals almost identical response patterns indicating that RAG-1 and RAG-2 transcription is coordinately regulated. Together, these results imply that the RAG-containing fragment in L4 fibroblasts carries most, if not all, control regions regulating the transcription of the RAG-1 and RAG-2 genes.
Döbbeling
U
U
Institut für Veterinärbiochemie, Universität Zürich, Switzerland.
Hobi
R
R
Berchtold
M W
MW
Kuenzle
C C
CC
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D005347:Fibroblasts / Q000276:immunology; D005803:Genes, Immunoglobulin / Q000235:genetics / Q000276:immunology; D016654:Genes, RAG-1 / Q000235:genetics* / Q000276:immunology; D051379:Mice; D012333:RNA, Messenger / Q000235:genetics; D011995:Recombination, Genetic; D015398:Signal Transduction / Q000235:genetics* / Q000276:immunology; D014162:Transfection
D012333:RNA, Messenger