STOCK Igf2^tm1.1Thor/J

Stock number: 032493
Product name: Igf2 flox
Research areas: Cell Biology Research, Metabolism Research, Research Tools

Description

These floxed mutant mice possess loxP sites flanking exon 4 of the Igf2 gene. This strain may be useful for generating conditional mutations in applications related to the regulation of growth and metabolism.

Detailed description

The targeted Igf2 gene encodes a polypeptide growth factor that is produced and secreted by adult pancreatic β cells and can act as a mitogen. Mutations in this gene have been associated with growth restriction, severe, with distinctive facies These mice possess loxP sites on either side of exon 4 of the targeted gene. Mice that are homozygous for this allele are viable and fertile. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exon 4 deleted in the cre-expressing tissues. Removal of the floxed sequence creates a null allele.

When bred to a strain with Cre recombinase expression in pancreatic beta cells (see Stock No. 026801 for example), this mutant mouse strain may be useful in studies of β cell proliferation.

 

Development

A targeting vector containing a FRT site flanked Neo selection cassette was utilized in the construction of this mutant. This selection cassette and a 5’ loxP site were inserted downstream of exon 4 of the targeted gene, and another loxP site was inserted upstream of exon 4. This construct was electroporated into unspecified embryonic stem (ES) cells. Correctly targeted (129S6/SvEvTac x C57BL/6NCrl)F1 derived G4 ES cells were injected into blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were crossed to unspecified FLP-deleter mice (on the C57BL/6J background) to excise the selection cassette. Mice that retained the loxP site flanked exon 4 were then bred to C57BL/6 mice to remove the FLP recombinase allele/transgene. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Igf2^tm1.1Thor
Name: targeted mutation 1.1, Bernard Thorens
MGI accession ID: MGI:6144126
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Igf2^lox
Marker symbol: Igf2
Marker name: insulin-like growth factor 2
Marker synonyms: C11orf43; GRDF; Igf-2; IGFII; IGF-II; M6pr; Mpr; MSA; Peg2; PP9974; RNIGF2; SRS3
Chromosome: 7
Strain of origin: (129S6/SvEvTac x C57BL/6NCrl)F1
Molecular note: Exon 4 was flanked by loxP sites. An FRT-flanked neomycin selection cassette was inserted downstream of exon 4 but before the second loxP site. Flp-mediated recombination removed the neomycin cassette.