B6.129(Cg)-Flt4^tm2.1Ali/OuluJ

Stock number: 037678
Product name: Vegfr3^lx
Research areas: Neurobiology Research, Research Tools

Description

Vegfr3^lx mice possess loxP sites flanking exon 1 of the Flt4 (FMS-like tyrosine kinase 4 also known as Vegfr) gene. These floxed mice are useful for tissue specific deletion of Flt4 when studying the development of the lymphatic, circulatory, and nervous systems.

Detailed description

Flt4 (FMS-like tyrosine kinase 4 also known as Vegfr) encodes a tyrosine kinase receptor for vascular endothelial grown factors C and D (VEGF-C, VEGF-D). In adults Flt4 is expressed in the lymphatic vasculature and in fenestrated blood vascular endothelial cells. In embryos, Flt4 is expressed on blood vessels and is involved in the remodeling of the blood vascular network. VEGFR-3 is also expressed in the neural stem cells of the subventricular zone (SVZ) of the adult brain where it has been reported to stimulate neurogenesis. Germline deletion of VEGFR-3 results in embryonic lethality by E10.5. These Vegfr3^lx/lx mice possess loxP sites flanking exon 1 and part of intron 1 of the FMS-like tyrosine kinase 4 (Flt4) gene. Mice that are homozygous for this allele are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exon 1 deleted in the cre-expressing tissues.

Development

The targeting vector is designed to insert a loxP site upstream of exon 1 followed by a neomycin resistance (neo) cassette flanked by FRT sites and loxP sites in intron 1 of the FMS-like tyrosine kinase 4 (Flt4) gene on chromosome 11. The construct was electroporated into (129X1/SvJ x 129S1/Sv)F1-Kitl⁺-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were aggregated with ICR morulae and the resulting chimeric blastocysts were implanted in pseudopregnant females. The resulting chimeric offspring were bred with mice carrying Tg(ACTFLPe)9205Dym mice on an unspecified background to delete the neo cassette, and progeny were crossed to remove the Flp-expressing transgene. These Vegfr3^lx/lx were backcrossed to C57BL/6NCrl mice for greater than 10 generations by the donating laboratory (see SNP notes below) and cryopreserved as sperm. Upon arrival, sperm will be recovered using C57BL/6NJ females (Stock No. 005304) for at least one generation to establish the colony.

In 2023, a 48 SNP (single nucleotide polymorphism) panel analysis, with 43 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. One of the 43 markers throughout the genome was segregating with 129, on Chromosome 7. Also, one marker on Chromosome 11 was segregating with 129, likely a passenger segment from Flt4 mutation. All 4 of the 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/6N;C57BL/6J genetic background.

Allele

Symbol: Flt4^tm2.1Ali
Name: targeted mutation 2.1, Kari Alitalo
MGI accession ID: MGI:3805195
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Vegfr3^lx
Marker symbol: Flt4
Marker name: FMS-like tyrosine kinase 4
Marker synonyms: CHTD7; FLT-4; FLT41; LMPH1A; LMPHM1; PCL; Vegfr3; VEGFR-3
Chromosome: 11
Strain of origin: (129X1/SvJ x 129S1/Sv)F1-Kitl⁺
Molecular note: A loxP site was inserted upstream of the translation initiation codon and a floxed, frt-flanked neo cassette was inserted downstream of exon 1. The frt flanked neo cassette was then removed by germ-line FLPe-mediated recombination.