B6(129S4)-Il33^tm1.1Bryc/J

Stock number: 030619
Product name: IL33^fl/fl-eGFP
Research areas: Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

IL33^fl/fl-eGFP mice possess loxP sites flanking exons 5-7 and an EGFP reporter in the 3' UTR of the interleukin 33 (Il33) locus. These mice may be useful for studying and tracking IL33 activity.

Detailed description

IL33^fl/fl-eGFP mice possess loxP sites flanking exons 5-7 of the interleukin 33 (Il33) gene. They also contain an EGFP reporter inserted into the 3' UTR. IL33 is a cytokine involved in the maturation of Th2 cells and the activation of mast cells, basophils, eosinophils and natural killer cells. Mice that are homozygous for this allele are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have part of the promoter and exons 5-7 deleted in the cre-expressing tissues. EGFP fluorescence is evident in all cell types that express IL33.

Mice express EGFP prior to Cre recombination, and the donating investigator is unsure of expression after Cre recombination in IL33 knock-out mice.

Development

The IL33^fl/fl-eGFP targeting vector was designed to insert a loxP site upstream of exon 5, and an FRT-flanked and loxP-flanked neomycin resistance (neo) cassette downstream of exon 7 of the interleukin 33 (IL33) gene. An internal ribosome entry site (IRES) fused to an enhanced green fluorescent protein sequence was inserted into the 3 prime UTR. The construct was electroporated into C57BL/6NTac-derived iTL IC1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts and resulting chimeric mice were bred with B6.129S4-Gt(ROSA)26Sor^tm2(FLP*)Sor/J mice (Stock No. 012930) to delete the neo cassette. Progeny were bred with C57BL/6J mice to remove the Flp-expressing transgene. Resulting IL33^fl/fl-eGFP mice were bred with C57BL/6J mice for at least 5 generations by the donating laboratory (see SNP note below). Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

In 2018, 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. Two 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: Il33^tm1.1Bryc
Name: targeted mutation 1.1, Paul Bryce
MGI accession ID: MGI:5897873
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Reporter
Synonyms: IL33^fl
Marker symbol: Il33
Marker name: interleukin 33
Marker synonyms: 9230117N10Rik; C9orf26; DVS27; IL1F11; Il-33; NFEHEV; NF-HEV; RGD1311155
Chromosome: 19
Strain of origin: C57BL/6NTac
Expressed genes: GFP,Green Fluorescent Protein,
Site of expression: EGFP fluorescence is observed in all cell types that express IL33.
Molecular note: The targeting vector is designed to insert a loxP site upstream of exon 5, and an FRT-flanked and loxP-flanked neomycin resistance (neo) cassette downstream of exon 7 of the gene. An internal ribosome entry site (IRES) fused to an enhanced green fluorescent protein sequence was inserted into the 3 prime UTR. Flp-mediated recombination removed the FRT-flanked neo cassette leaving exons 5 through 7 floxed.