B6.Cg-Gt(ROSA)26Sor^{tm3(CEBPB)Myz}/J

Stock number: 035506
Product name: Rosa26-C/EBPβ^loxtg
Research areas: Cell Biology Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

Rosa-hC/EBPβ mice conditionally express Myc-tagged human CEBPB (CCAAT/enhancer binding protein (C/EBP), beta) and may be useful for the study of immune and inflammatory responses and endoplasmic reticulum-related autophagy.

Detailed description

Cebpb (CCAAT/enhancer binding protein (C/EBP), beta) encodes a transcription factor containing a basic leucine zipper (bZIP) domain important in the regulation of genes involved in immune and inflammatory responses. Rosa-hC/EBPβ mice conditionally express Myc-tagged human CEBPB. The transgene contains a loxP-flanked puromycin cassette followed by a Myc-tagged human CEBPB cDNA. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have puro deleted in cre-expressing tissues - allowing expression of human CEBPB. Homozygous Rosa-hC/EBPβ mice are viable, but subfertile. At JAX, all homozygous mice exhibit weight gain by weaning, with 3 of 9 mice appearing significantly obese. The donating investigator reports that in general Rosa26 floxed homzygotes can be leaky.

When combined with mice expressing Cre recombinase in liver (B6.Cg-Speer6-ps1^{Tg(Alb-cre)21Mgn}/J; Stock No. 003574), progeny exhibit liver steatosis and increased protein levels of a starvation-induced truncated isoform of the ER-resident cargo receptor, RETREG1 (Fam134B-2). CEBPB overexpression increases FAM134B-2 recruitment into autophagosomes and lysosomal degradation.

Development

RMCE (recombinase-mediated cassette exchange) was utilized to insert a Myc-tagged human CEBPB sequence into the Gt(ROSA)26Sor locus. R26FNF3-1F1 (1F1) embryonic stem (ES) cells were transfected with plasmids pFLSLF2-Myc human CEPBP (carrying loxP pA-puromycin-PGK-Sv40 pA (in reverse orientation)-loxP-Myc-CEBPB-WPRE-BGH pA) and pCAG-Flpe (expressing FLP recombinase). The 1F1 ES cell line used to generate the mutation was created by targeting Gt(ROSA)26Sor with an FRT- and F3-flanked PGK-neomycin selection cassette by homologous recombination in (C57BL/6J x 129X1/SvJ)F1-derived EC7.1 ES cells. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were bred to C57BL/6J mice and progeny were backcrossed to C57BL/J for at least 10 generations. Upon arrival, mice were bred to C57BL/6J for at least one generation to establish the colony.

Allele

Symbol: Gt(ROSA)26Sor^{tm3(CEBPB)Myz}
Name: targeted mutation 3, Makoto Miyazaki
MGI accession ID: MGI:6450900
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Inserted expressed sequence; Humanized sequence
Synonyms: Rosa26-C/EBPbeta^loxtg
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Marker synonyms: beta geo; Gtrgeo26; Gtrosa26; R26; ROSA26; SETD5-AS1; Thumpd3as1
Chromosome: 6
Strain of origin: (C57BL/6J x 129X1/SvJ)F1
Site of expression: cre-inducible
Molecular note: RMCE (recombinase-mediated cassette exchange) was utilized to insert a Myc-tagged human CEBPB sequence into the Gt(ROSA)26Sor locus. R26FNF3-1F1 (1F1) embryonic stem (ES) cells were transfected with plasmids pFLSLF2-Myc human CEPBP (carrying loxP pA-puromycin-PGK-Sv40 pA (in reverse orientation)-loxP-Myc-CEBPB-WPRE-BGH pA) and pCAG-Flpe (expressing FLP recombinase). The 1F1 ES cell line used to generate the mutation was created by targeting Gt(ROSA)26Sor with an FRT- and F3-flanked PGK-neomycin selection cassette by homologous recombination in (C57BL/6J x 129X1/SvJ)F1-derived EC7.1 ES cells.