Germ-line transcription occurs on both the functional and the non-functional alleles of immunoglobulin constant heavy chain genes.
In B cells undergoing class switching, recombination is usually directed to the same switch sequences on both homologous chromosomes and is generally preceded by germ-line transcription initiated from I promoters upstream of immunoglobulin constant heavy chain genes. Whether germ-line transcription occurs on both alleles or is restricted to the productive one has not been directly addressed before. To clearly distinguish between these two possibilities, a system is needed in which one might detect allele-specific germ-line transcripts. We used homologous recombination to set up two in vivo systems in which one gamma3 allele was marked by a loxP sequence whereas the other allele was silenced by inhibiting mu heavy chain production. Here, we provide evidence that germ-line transcription occurs on both the functional and the non-functional alleles.
Delpy
Laurent
L
CNRS UMR 6101, Laboratoire d'Immunologie, Faculté de Médecine, Limoges, France.
Le Bert
Marc
M
Cogné
Michel
M
Khamlichi
Ahmed Amine
AA
D000483:Alleles; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D020868:Gene Silencing; D018390:Gene Targeting; D005803:Genes, Immunoglobulin; D017578:Immunoglobulin Class Switching; D007127:Immunoglobulin Constant Regions / Q000235:genetics*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D051379:Mice; D018345:Mice, Knockout; D014158:Transcription, Genetic
D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains