C.129X1-Il4ra^tm1Tch/J

Stock number: 007680
Research areas: Cell Biology Research, Diabetes and Obesity Research, Hematological Research, Immunology, Inflammation and Autoimmunity Research, Internal/Organ Research, Research Tools

Description

These IL4Rα Y500F mutant mice may be useful in immunological studies of mitogenic signal transduction in response to IL-4, specifically antigen-specific antibody responses, allergic airway inflammation, and asthma.

Detailed description

Mice homozygous for this "IL4Rα Y500F" mutant allele are viable and fertile. The mice express a mutant IL4Rα chain with a phenylalanine substitution at the proximal tyrosine residue (Y500F) in the cytoplasmic tail. This residue is a critical component of the insulin/interleukin-4 receptor (I4R) motif, and is required for binding by phosphotyrosine-binding domain (PTB) adaptor proteins and for initiating subsequent downstream signaling cascades in response to IL-4. Allele-specific PCR verifies the amino acid substitution. The Y500F mutation abrogates insulin receptor substrate-2 (IRS-2) phosphorylation, and impairs IL-4-induced CD4+ lymphocyte proliferation with no reported effect on Stat6 activation, IL-4-responsive gene product up-regulation, or Th cell differentiation under Th2 polarizing conditions. In vivo, the Y500F mutation is associated with increased allergen-induced IgE production, airway hyper-responsiveness (AHR), tissue eosinophilia, goblet cell metaplasia, and mucus production. These IL4Rα Y500F mutant mice may be useful in immunological studies of mitogenic signal transduction in response to IL-4, specifically antigen-specific antibody responses, allergic airway inflammation, and asthma.

Development

The targeting vector was designed (by site-directed mutagenesis) to change an adenine to thymidine at basepair 1735 of the murine IL-4Rα cDNA sequence, resulting in a corresponding single amino acid substitution of tyrosine to phenylalanine at codon 500 (Y500F). A loxp-flanked PGK-neo cassette was also inserted within intron 11. The construct was electroporated into 129X1/SvJ-derived RW4 embryonic stem (ES) cells. Correctly targeted ES cells were transiently transfected with a cre-expressing vector to remove the selection cassette (leaving a single loxp site in intron 11) and then injected into C57BL/6 blastocysts. The resulting chimeric males were crossed to BALB/c females. Heterozygotes were bred to BALB/c for 12 generations prior to arrival at The Jackson Laboratory.

Allele

Symbol: Il4ra^tm1Tch
Name: targeted mutation 1, Talal A Chatila
MGI accession ID: MGI:2680722
Generation method: Targeted
Attributes: Inserted expressed sequence
Marker symbol: Il4ra
Marker name: interleukin 4 receptor, alpha
Chromosome: 7
Strain of origin: 129X1/SvJ
Molecular note: A single A to T substitution was created at the position equivalent to 1735 of the cDNA. This caused a codon change for amino acid residue 500 from tyrosine to phenylalanine (Y500F) disrupting the PTB domain. In addition, a floxed PGK-neomycin resistance cassette was inserted into intron 11. This cassette was removed from successfully targeted clones by transient transfection with a Cre recombinase. The mutant is transcribed at rates equivalent to those of wild-type as indicated by RT-PCR.