B6;129-Igf1r^tm2Arge/J

Stock number: 012251
Product name: Igf1r^(lox)
Strain synonyms: Igf1r^c
Research areas: Research Tools

Description

These floxed mutant mice possess loxP sites flanking exon 3 of the Igf1r gene. This strain may be useful for generating conditional mutations for studies of mammary tumorigenesis, myelination and bone development.

Detailed description

These mice possess loxP sites on either side of exon 3 of the targeted 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 these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exon 3 deleted in the cre-expressing tissue(s).

When crossed with a mouse overexpressing constitutively active Kras and expressing mammary gland specific Cre recombinase, this IGF1R^Lox mutant mouse strain may be useful in studies of mammary tumorigenesis (Proc Natl Acad Sci U S A 2009 Feb 17;106(7):2359-64).

When bred to a strain with Cre recombinase expression in the CNS, this mutant mouse strain may be useful in studies of myelination (Genesis 2000 Feb;26(2):133-5).

When bred to a strain carrying Tg(BGLAP-cre)1Clem (Stock No. 019509), Cre recombinase expression in osteoblasts results in abnormal bone matrix mineralization (J Biol Chem 2002 Nov 15;277(46):44005-12).

When bred to a strain carrying Tg(Tek-cre)1Ywa (Stock No. 008863), Cre recombinase expression in endothelial cells results in impaired endothelial regeneration following arterial injury.

Development

A targeting vector containing a loxP site flanked neo selection cassette was utilized in the construction of this mutant. This selection cassette was inserted downstream of exon 3 of the targeted gene, and another loxP site was inserted upstream of exon 3. This construct was electroporated into 129 derived embryonic stem (ES) cells. Correctly targeted ES cells were transiently transfected with a Cre expression plasmid for the purpose of removing the selectable marker cassette. ES cells that had successfully undergone Cre recombination and no longer retained the cassette but did retain the loxP-flanked exon 3 were injected into recipient blastocysts. The resulting chimeric animals were crossed to other mutant strains. Upon arrival at The Jackson Laboratory the mice were crossed to C57BL/6J at least once to remove the other mutant allele and to establish the colony.

Allele

Symbol: Igf1r^tm2Arge
Name: targeted mutation 2, Argiris Efstratiadis
MGI accession ID: MGI:2389580
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Igf1r
Marker name: insulin-like growth factor I receptor
Chromosome: 7
Strain of origin: 129/SvEv
Molecular note: Exon 3 was flanked by a floxed neo cassette in intron 2 and a single loxP site in intron 3.