title: R/L, a double reporter mouse line that expresses luciferase gene upon Cre-mediated excision, followed by inactivation of mRFP expression.
abstract: The Cre/loxP system has become an important tool for the conditional gene knockout and conditional gene expression in genetically engineered mice. The applications of this system depend on transgenic reporter mouse lines that provide Cre recombinase activity with a defined cell type-, tissue-, or developmental stage-specificity. To develop a sensitive assay for monitoring Cre-mediated DNA excisions in mice, we generated Cre-mediated excision reporter mice, designated R/L mice (R/L: mRFP(monomeric red fluorescent protein)/luciferase), express mRFP throughout embryonic development and adult stages, while Cre-mediated excision deletes a loxP-flanked mRFP reporter gene and STOP sequence, thereby activating the expression of the second reporter gene luciferase, as assayed by in vivo and ex vivo bioluminescence imaging. After germ line deletion of the floxed mRFP and STOP sequence in R/L mice by EIIa-Cre mice, the resulting luciferase transgenic mice in which the loxP-mRFP-STOP-loxP cassette is excised from all cells express luciferase in all tissues and organs examined. The expression of luciferase transgene was activated in liver of RL/Alb-Cre double transgenic mice and in brain of RL/Nestin-Cre double transgenic mice when R/L reporter mice were mated with Alb-Cre mice and Nestin-Cre mice, respectively. Our findings reveal that the double reporter R/L mouse line is able to indicate the occurrence of Cre-mediated excision from early embryonic to adult lineages. Taken together, these findings demonstrate that the R/L mice serve as a sensitive reporter for Cre-mediated DNA excision both in living animals and in organs, tissues, and cells following necropsy.
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Junshuang
authors.initials: J
authors.lastname: Jia
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Lin
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Lin
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Taoyan
authors.initials: T
authors.lastname: Lin
authors.affiliation: b Laboratory Animal Center, Southern Medical University, Guangzhou 510515, China.
authors.forename: Bangzhu
authors.initials: B
authors.lastname: Chen
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Weichao
authors.initials: W
authors.lastname: Hao
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Yushuang
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Meijuan
authors.initials: M
authors.lastname: Dian
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.
authors.forename: Kaitai
authors.initials: K
authors.lastname: Yao
authors.affiliation: a Guangdong Provincial Key Laboratory of Cancer Immunotherapy and Guangzhou Key Laboatory of Tumor Immunology Research, Cancer Research Institute, Southern Medical University, Guangzhou 510515, China.|b Laboratory Animal Center, Southern Medical University, Guangzhou 510515, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Xiao
authors.affiliation: b Laboratory Animal Center, Southern Medical University, Guangzhou 510515, China.
authors.forename: Weiwang
authors.initials: W
authors.lastname: Gu
mesh_terms: D000818:Animals; D005260:Female; D015870:Gene Expression; D055786:Gene Knockout Techniques; D017930:Genes, Reporter; D059765:Homologous Recombination; D019426:Integrases / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008156:Luciferases / Q000235:genetics*; D008164:Luminescent Proteins / Q000235:genetics*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D010641:Phenotype; D015533:Transcriptional Activation; D000097573:Red Fluorescent Protein
chemical_list: D019426:Integrases; D008156:Luciferases; D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein; C045073:Cre recombinase
keywords: Cre transgenic mice; Cre/loxP system; conditional gene expression and knockout; expression et inactivation conditionnelle; luciferase; luciférase; monomeric red fluorescent protein; protéine fluorescente rouge monomérique; souris transgéniques Cre; système Cre/loxP