Insulators to improve expression of a 3(')IgH LCR-driven reporter gene in transgenic mouse models.
A locus control region (LCR) containing four transcriptional enhancers lies downstream of the IgH chain locus. We studied transgenes carrying a 3(')IgH LCR-driven GFP reporter gene for expression and B cell differentiation stage specificity. We also compared transgenes that were or were not flanked by two copies of the beta-globin HS4 insulator, an element defined by its ability to protect transgenes from the influences of surrounding genes at the insertion site. Results indicate that insulators are instrumental in sustaining GFP expression in GFP-3(')LCR transgenic mice when they were included. Flow cytometry experiments reported a strictly B cell specific GFP expression from pre-B cells in bone marrow to mature B cells in spleen. Despite addition of 5(')HS4 insulators to the GFP-3(')LCR construct, complete transgene silencing occurred in some transgenic lines and was systematically observed in ageing animals from all lines.
Guglielmi
Laurence
L
UMR CNRS 6101, Faculté de Médecine, 2 rue Dr Marcland, 87025, Limoges, France.
Le Bert
Marc
M
Truffinet
Véronique
V
Cogné
Michel
M
Denizot
Yves
Y
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D015870:Gene Expression; D016654:Genes, RAG-1; D017930:Genes, Reporter; D005914:Globins / Q000235:genetics; D049452:Green Fluorescent Proteins; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D038101:Insulator Elements; D019901:Locus Control Region; D008164:Luminescent Proteins / Q000096:biosynthesis / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D012333:RNA, Messenger / Q000096:biosynthesis; D013234:Stem Cells / Q000378:metabolism; D019076:Transgenes
D007143:Immunoglobulin Heavy Chains; D008164:Luminescent Proteins; D012333:RNA, Messenger; D049452:Green Fluorescent Proteins; D005914:Globins