B6.Cg-Tg(Wfs1-cre/ERT2)2Aibs/J

Stock number: 009614
Product name: Wfs1-Tg2-CreERT2
Research areas: Neurobiology Research, Research Tools

Description

These Wfs1-Tg2-CreERT2 mice express a tamoxifen-inducible Cre recombinase under the control of the mouse Wfs1 (Wolfram syndrome 1 homolog (human)) promoter/enhancer regions, and may be useful for generating conditional mutations for studying gain or loss of function and/or fate mapping in subgroups of brain tissues (including cortex, hippocampus, and cerebellum).

Detailed description

Hemizygous Wfs1-Tg2-CreERT2 mice are viable and fertile. As the Cre-ERT2 fusion gene is under control of the Wfs1 promoter/enhancer regions within the BAC transgene, cre activity is directed to cortex, hippocampus, and cerebellum only following tamoxifen administration. The donating investigators report that Cre recombinase expression for this Wfs1-Tg2-CreERT2 line is more restricted than the Wfs1-Tg3-CreERT2 line (Stock No. Stock No. 009103). The donating investigators may not have assessed expression in tissues other than brain. The Cre-ERT2 fusion protein consists of Cre recombinase fused to a triple mutant form of the human estrogen receptor; which does not bind its natural ligand (17β-estradiol) at physiological concentrations but will bind the synthetic estrogen receptor ligands 4-hydroxytamoxifen (OHT or tamoxifen) and, with lesser sensitivity, ICI 182780. Restricted to the cytoplasm, Cre-ERT2 can only gain access to the nuclear compartment after exposure to tamoxifen. To counteract the mixed estrogen agonist effects of tamoxifen injections, which can result in late fetal abortions in pregnant mice, progesterone may be coadministered. When Wfs1-Tg2-CreERT2 mice are bred with mice containing a loxP-flanked sequence of interest, tamoxifen-inducible, Cre-mediated recombination will result in deletion of the floxed sequence(s) in the offspring. As such, these Wfs1-Tg2-CreERT2 mice may be useful for generating conditional mutations for studying gain or loss of function and/or fate mapping in subgroups of brain tissues (including cortex, hippocampus, and cerebellum).

For characterization information, see images at the Allen Institute for Brain Science website (Wfs1-Tg2-CreERT2 images).

Development

The 196 kb C57BL/6J mouse bacterial artificial chromosome (BAC) RP23-405O19, containing the entire Wfs1 locus (and other genes), was modified by targeting a CreERT2 fusion gene (Cre-ER^T2; Cre recombinase fused to a G400V/M543A/L544A triple mutation of the human estrogen receptor ligand binding domain), SV40 polyA signal, and frt-flanked neomycin cassette to the ATG start site of the Wfs1 locus. The targeted BAC sequences were further modified using FLP recombination to remove the selection cassette and linearized to remove its original vector backbone. The resulting modified BAC was microinjected into embryos from B6C3 mice ((C57BL/6 x C3H)F1 x C57BL/6). Transgenic mice from founder line Wfs1-Tg2-CreERT2 were bred to R26R-EYFP (C57BL/6J congenic background; Stock No. 006148). Next, Wfs1-Tg2-CreERT2 mice were bred with C57BL/6J inbred mice (selectively removing the R26-EYFP allele) for two generations prior to arrival at The Jackson Laboratory. Upon arrival, transgenic mice were bred with C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish this colony.

Allele

Symbol: Tg(Wfs1-cre/ERT2)2Aibs
Name: transgene insertion 2, Ed Lein
MGI accession ID: MGI:3850189
Generation method: Transgenic
Attributes: Recombinase-expressing; Inducible
Marker symbol: Tg(Wfs1-cre/ERT2)2Aibs
Marker name: transgene insertion 2, Ed Lein
Chromosome: UN
Strain of origin: (C57BL/6 x C3H)F1 x C57BL/6
Expressed genes: cre,cre recombinase,bacteriophage P1; ESR1,estrogen receptor 1,human
Site of expression: Hemizygous Wfs1-Tg2-CreERT2 mice are viable and fertile. As the Cre-ERT2 fusion gene is under control of the Wfs1 promoter/enhancer regions within the BAC transgene, cre activity is directed to cortex, hippocampus, and cerebellum only following taxomifen administration.
Molecular note: The 196 kb C57BL/6J mouse bacterial artificial chromosome (BAC) RP23-405O19, containing the entire Wsf1 locus (and other genes), was modified by targeting a CreERT2 fusion gene (Cre-ERT2; Cre recombinase fused to a G400V/M543A/L544A triple mutation of the human estrogen receptor ligand binding domain), SV40 polyA signal, and frt-flanked neomycin cassette to the ATG start site of the Wsf1 locus. The targeted BAC sequences were further modified using FLP recombination to remove the selection cassette and linearized to remove its original vector backbone. The resulting modified BAC was microinjected into embryos from B6C3 mice ((C57BL/6 x C3H)F1 X C57BL/6).