Mice homozygous for this Fc epsilon RI alpha chain targeted mutation have an abnormal type I hypersensitivity reaction and may be useful in studies of anaphylaxis, and immunological response to allergens.
IMR Colony, The Jackson Laboratory
Mice that are homozygous for the targeted mutation are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. Cultured bone marrow-derived mast cells from homozygotes, that have been activated with interleukin-3, do not bind to monomeric IgE as analyzed by flow cytometry. Mice homozygous for the mutant allele are resistant to IgE induced passive cutaneous and systemic anaphylaxis and are more susceptible to IgG1-dependent passive and active systemic anaphylaxis treatments.
In an attempt to offer alleles on well-characterized or multiple genetic backgrounds, alleles are frequently moved to a genetic background different from that on which an allele was first characterized. This is the case for the strain above. It should be noted that the phenotype could vary from that originally described. We will modify the strain description if necessary as published results become available.
For the Fcer1atm1Knt allele, a targeting vector containing neomycin resistance and herpes simplex virus thymidine kinase genes was used to disrupt exon 4, which encodes an immunoglobulin domain. The construct was electroporated into 129S2/SvPas derived D3 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting chimeric animals were crossed to BALB/cJ mice, and then backcrossed to the same for 20 generations. The mice were then crossed to transgenic mice carrying Tg(FCER1A)1Bhk. This double mutant was backcrossed to C57BL/6 for more than 8 generations.
The double mutant B6.Cg-Fcer1atm1Knt Tg(FCER1A)1Bhk/J strain arrived at The Jackson Laboratory (as Stock No. 010506). Upon arrival, some mice were selectively bred with C57BL/6J inbred mice (Stock No. 000664) to remove the transgene and harbor only the Fcer1atm1Knt mutation (Stock No. 010512).
|Allele Name||targeted mutation 1, Jean-Pierre Kinet|
|Allele Type||Targeted (Null/Knockout)|
|Allele Synonym(s)||Fc epsilon RI alpha chain-; FcepsilonR1alpha-; FcepsilonRI-; Fcer1a-; Fcer1atm1Rav; FcerIa-|
|Gene Symbol and Name||Fcer1a, Fc receptor, IgE, high affinity I, alpha polypeptide|
|Strain of Origin||129|
|General Note||ES cell line = D3 (129S2/SvPas) or E14TG2a (129P2/OlaHsd).|
|Molecular Note||Exon 4, encoding an immunoglobulin domain, was disrupted by the insertion of a neomycin selection cassette. The absence of a functional encoded protein on the cell surface was determined by fluorescence activated cell sorting analysis of bone marrow mast cells obtained from homozygous mutant mice.|
|Mutations Made By|| |
Devin Turner, Beth Israel Deaconess Medical Center
When maintaining Fcer1atm1Knt mutant mice as a live colony, homozygous mice may be bred together.
When using the B6.129S2(Cg)-Fcer1atm1Knt/J mouse strain in a publication, please cite the originating article(s) and include JAX stock #010512 in your Materials and Methods section.