STOCK Foxj1^{tm1.1(cre/ERT2/GFP)Htg}/J

Stock number: 027012
Product name: Foxj1^CreERT2::GFP
Research areas: Research Tools

Description

These Foxj1^CreERT2::GFP knock-in/knock-out mice express GFP and tamoxifen inducible Cre recombinase in epithelial cells with motile cilia. They are suitable for use in applications related to the study of ciliogenesis, as well as lineage tracing of Foxj1 expressing cells.

Detailed description

The Foxj1 gene encodes for a transcription factor that is involved in regulation of motile cilia production and left-right asymmetry determination. Polymorphisms in the human FOXJ1 gene are associated with systemic lupus erythematosus and allergic rhinitis. These mice carry an eGFPCreERt2 (GCE) fusion gene knock in allele of the Foxj1 gene. Mice homozygous for the knock in mutation recapitulates the null phenotype: exhibiting postnatal lethality, situs inversus and hydrocephalus with lack of apical ependymal cell cilia. Mice that are heterozygous for the targeted mutation are viable and fertile. When crossed to a reporter strain, tamoxifen treatment induces permanent labeling of Foxj1 expressing cells, and cells derived from putative Foxj1 expressing progenitor cells. Expression of the cre/ERT2/GFP fusion gene was restricted to the cytoplasm of ependymal cells in brain sections of mice not treated with tamoxifen. With tamoxifen treatment, the majority of GFP positive cells co-labelled with the reporter in the nuclei of ependymal cells. Tamoxifen treatment of pregnant female mice allows induction of the cre/ERT2/GFP in the choroid plexus of the embryos. The expression pattern of the cre/ERT2/GFP is similar to the endogenous pattern of Foxj1 gene expression. Tamoxifen inducible cre recombinase activity is detected in epithelial cells with motile cilia in the lungs, oviducts and seminiferous tubules, as well as spermatocytes and spermatozoa.

Development

A targeting vector containing a cDNA encoding an eGFPCreERt2 (GCE) fusion protein and a FRT site flanked neo cassette was used to insert the GFP::CreERT2 upstream of the start codon in exon 2 of the Foxj1 gene. The construct was electroporated into 129P2/OlaHsd derived E14Tg2a.4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting male chimeric animals were crossed to C57BL6/J females. The mice were crossed with FLPeR mice, on the 129S4/SvJaeSor background (Stock No. 003946), to excise the FRT site flanked neo cassette. The mice may have been crossed to another mutant line on the CD1 background. The strain was then cryopreserved as sperm, and recovered on C57BL/6J (Stock No. 000664) at least once to establish the colony.

Allele

Symbol: Foxj1^{tm1.1(cre/ERT2/GFP)Htg}
Name: targeted mutation 1.1, H Troy Gashghaei
MGI accession ID: MGI:5585638
Generation method: Targeted
Attributes: Recombinase-expressing; Reporter; Inducible
Marker symbol: Foxj1
Marker name: forkhead box J1
Chromosome: 11
Strain of origin: 129P2/OlaHsd
Expressed genes: GFP,Green Fluorescent Protein,; cre/ERT2,Cre recombinase and estrogen receptor 1 (human) fusion gene,
Site of expression: GFP and tamoxifen inducible Cre recombinase are expressed in epithelial cells with motile cilia.
Molecular note: A cassette composed of a GFP, cre, an ERT2 and finally an FRT flanked neomycin selection cassette was inserted in exon 2 before the translation start site. The selection cassette was subsequently removed by flp recombinase expression.