C57BL/6-Gt(ROSA)26Sor^{tm3(CAG-MIR17-92,-EGFP)Rsky}/J

Stock number: 008517
Product name: miR-17-92
Research areas: Apoptosis Research, Cancer Research, Developmental Biology Research, Immunology, Inflammation and Autoimmunity Research, Internal/Organ Research, Mouse/Human Gene Homologs, Research Tools

Description

These mice harbor the miR-17-92 transgene targeted to the Gt(ROSA)26Sor locus. miR-17-92 transgenic mice allow the cre-inducible expression of the human miR-17-92 cluster which has been associated with lymphomas and other cancers, autoimmune defects, and altered expression of tumor suppressor and pro-apoptotic genes.

Detailed description

Mice homozygous for the "miR-17-92 transgene" conditional allele are viable and fertile, with a loxP-flanked Neo-STOP cassette preventing transcription of the downstream bicistronic sequences (human miR-17-92 cluster (encoding the precursor of seven miRNA molecules; miR-17-5p, miR-17-3p, miR-18a, miR-19a, miR-20a, miR-19b and miR-92) and EGFP). When bred to mice that express Cre recombinase, the resulting offspring will have the STOP cassette deleted in the cre-expressing tissue(s); resulting in expression of the human miR-17-92 cluster. Because the synthetic CAG promoter driven miR-17-92 transgene was targeted for insertion into the Gt(ROSA)26Sor locus, expression of the transgene is determined by which tissue(s) express Cre recombinase. EGFP fluorescence, however, is not reported following exposure to Cre recombinase (presumably due to RNaseIII excision of the stem-loop structures encoding individual miRNA destabilizing the EGFP portion of the primary transcript). These miR-17-92 transgenic mice allow inducible expression of the human miR-17-92 cluster that has been associated with lymphomas and other cancers, autoimmune defects, and altered expression of tumor suppressor and pro-apoptotic genes.

Development

The "miR-17-92 transgene" was designed with (from 5' to 3') a synthetic CAG promoter, a loxP-flanked Neo-STOP cassette, a genomic DNA fragment encoding the human miR-17-92 cluster (encoding the precursor of seven miRNA molecules; miR-17-5p, miR-17-3p, miR-18a, miR-19a, miR-20a, miR-19b and miR-92), a frt-flanked internal ribosomal entry site-enhanced green fluorescent protein (IRES-EGFP), and polyadenylation signal. This transgene was inserted between exons 1 and 2 of the Gt(ROSA)26Sor locus via electroporation into C57BL/6-derived Bruce-4 embryonic stem (ES) cells. Correctly targeted ES cells were selected and chimeric animals were bred to generate mutant mice. These "miR-17-92 transgenic" mice were maintained on a C57BL/6 genetic background as a homozygous colony for many generations (see SNP note below). Upon arrival at The Jackson Laboratory, mice were bred with C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.

A 32 SNP (single nucleotide polymorphism) panel analysis, with 27 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the rederived living colony at The Jackson Laboratory Repository. While the 27 markers throughout the genome suggested a C57BL/6 genetic background, 2 of 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J ; C57BL/6N genetic background.

Allele

Symbol: Gt(ROSA)26Sor^{tm3(CAG-MIR17-92,-EGFP)Rsky}
Name: targeted mutation 3, Klaus Rajewsky
MGI accession ID: MGI:3778920
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Reporter; Humanized sequence; No functional change
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Chromosome: 6
Strain of origin: B6.Cg-Thy1^a
Expressed genes: GFP,Green Fluorescent Protein,; Mirn17-92,microRNA cluster 17-92,
Site of expression: When bred to mice that express Cre recombinase, the resulting offspring will have the STOP cassette deleted in the cre-expressing tissue(s); resulting in expression of the human miR-17-92 cluster. EGFP fluorescence, however, is not reported following exposure to Cre recombinase.
Molecular note: A cassette containing the chicken beta actin promoter CAG driving the expression of a floxed neo-STOP cassette followed by cDNA encoding human MIRN 17, 18a, 19a, 20a, 19b and 92 plus an frt-flanked IRES-EGFP cassette and a poly-adenylation site were inserted into the ROSA locus. This allele is also a knockin allele that allows for expression of the human MIRNs contained within it following the cre-mediated removal of the neo-STOP cassette.