B6;SJL-Tg(Foxl1-cre)1Khk/J

Stock number: 017738
Research areas: Research Tools

Description

Mice harboring the Foxl1-Cre transgene express Cre recombinase under the control of the mouse Foxl1, forkhead box L1, promoter, in the mesenchymal cells of the stomach and intestine, and in oval cells in injured liver. They may be useful for generating conditional mutations in gastrointestinal mesenchyme and liver progenitor cells.

Detailed description

These transgenic mice express Cre recombinase under the control of the mouse Foxl1, forkhead box L1, promoter. Foxl1 is expressed in the stomach and intestine, and in oval cells in injured liver tissue. Oval cells are bipotential progenitor cells that differentiate into cholangiocytes and hepatocytes. Cre recombinase expression is detected in the mesenchymal cells of the stomach and intestine, and in cells of the liver portal triad after injury, mimicking the endogenous Foxl1 expression pattern. Mice hemizygous for the transgenic insert are viable and fertile. The Donating Investigator reports that homozygotes are not viable.

Development

The mouse bacterial artificial chromosome (BAC) RP23-446J14 containing the entire Foxl1 promoter and 189kb of flanking sequence, including the coding region, was modified in 2 steps. First, the Foxc2 coding region was replaced with an FRT site-flanked kanamycin cassette (to inactivate expression of Foxc2). Transient arabinose-inducible FLP recombinase expression was used to remove the kanamycin selection cassette. Next, the Foxl1 coding region was replaced with IRES-cre sequence. The modified BAC was then linearized and microinjected into (C57BL/6 X SJL)F1 fertilized oocytes. Founder animals were maintained on the B6;SJL background. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.

Allele

Symbol: Tg(Foxl1-cre)1Khk
Name: transgene insertion 1, Klaus H Kaestner
MGI accession ID: MGI:3769667
Generation method: Transgenic
Attributes: Recombinase-expressing
Marker symbol: Tg(Foxl1-cre)1Khk
Marker name: transgene insertion 1, Klaus H Kaestner
Chromosome: UN
Strain of origin: (C57BL/6 x SJL)F1
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: removal of kanamycin by flp-mediated recombination results in the expression of Cre in the mesenchymal cells of the stomach and intestines.
Molecular note: Using BAC RP23-446J14, the researchers replaced the Foxl1 open reading frame with an IRES-cre cassette and the Foxc2 gene with an frt-flanked kanamycin cassette to prevent any expression from it. The kanamycin was later removed by flp-mediated recombination. Cre is expressed in the mesenchymal cells of the stomach and intestines.