C.129X1-Il4ra^tm2Tch/J

Stock number: 007746
Research areas: Cell Biology Research, Hematological Research, Immunology, Inflammation and Autoimmunity Research, Internal/Organ Research, Research Tools

Description

These Il4ra^R576 mutant mice (harboring the Q576R polymorphism) may be useful in immunological studies of mitogenic signal transduction, specifically antigen-specific antibody responses, allergic airway inflammation, atopy, and asthma.

Detailed description

Mice homozygous for this IL4Rα Q576R polymorphic allele (Il4ra^R576) are viable and fertile. The mutation introduces an arginine substitution at glutamine 576 (Q576R) in the protein sequence. This polymorphism is associated with severe asthma susceptibility and rapid smoking-associated lung function decline in human populations. Allele-specific PCR verifies the amino acid substitution. Homozygous mice exhibit heightened IgE responses in vivo, and augmented antigen- and IL-13-driven allergic airway inflammation. T cells from homozygotes show increased production of IL-4 in a Th2 polarized milieu. The R576 substitution is associated with enhanced Erk kinase activation with no reported effect on the activation of other canonical IL-4Rα-coupled pathways. These Il4ra^R576 mutant mice may be useful in immunological studies of mitogenic signal transduction, specifically antigen-specific antibody responses, allergic airway inflammation, atopy, and asthma.

Development

Two base pair substitutions, (adenine (A) to guanine (G) and G to A at basepair 1964 and 1965, respectively), were introduced into the Il4ar gene using site-directed mutagenesis. These mutations result in a single amino acid substitution of glutamine to arginine at codon 576 (Q576R). A targeting vector which included these two mutations and a loxp-flanked PGK-neo cassette inserted within intron 11. 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 PGK-neo 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/cAnNTac females. Heterozygotes were bred to BALB/cAnNTac for at least 10 generations prior to the strain's arrival at The Jackson Laboratory.

Allele

Symbol: Il4ra^tm2Tch
Name: targeted mutation 2, Talal A Chatila
MGI accession ID: MGI:3720593
Generation method: Targeted
Marker symbol: Il4ra
Marker name: interleukin 4 receptor, alpha
Chromosome: 7
Strain of origin: 129X1/SvJ
Molecular note: The targeting vector was designed (by site-directed mutagenesis) to change the alanine-guanine to guanine-alanine at basepair 1964-65 of murine IL-4Ra cDNA, corresponding to a single amino acid substitution of glutamine to arginine at codon 576 (Q576R). This also inserted a loxp-flanked PGK-neo cassette 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.