B6.129P2(SJL)-Myd88^tm1Defr/J

Stock number: 008888
Product name: Myd88^fl
Research areas: Apoptosis Research, Cancer Research, Cell Biology Research, Developmental Biology Research, Hematological Research, Immunology, Inflammation and Autoimmunity Research, Internal/Organ Research, Neurobiology Research, Research Tools

Description

These Myd88^fl mice have loxP sites flanking exon 3 of the myeloid differentiation primary response gene 88 (Myd88). These mutant mice may be useful for Cre-lox studies of signal transduction, Toll-like receptor signaling and natural killer cells.

Detailed description

Myd88^fl mice have loxP sites flanking exon 3 of the myeloid differentiation primary response gene 88 (Myd88). Mice that are homozygous for this allele are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exon 3 deleted in the cre-expressing tissue(s).

When bred to a strain with inducible Cre recombinase expression in dendritic cells (see Stock No. 008068 for example), this mutant mouse strain may be useful in studies of Toll-like receptor signaling during immune responses.

When bred to a strain with Cre recombinase expression in hematopoietic cells (see Stock No. 008610 for example), this mutant mouse strain may be useful in studies of Toll-like receptor signaling and natural killer cells.

When bred to a strain with Cre recombinase expression in villi and crypt cells of the small and large intestines (see Stock No. 004586 for example), this mutant mouse strain may be useful in studies of microbial intestinal flora.

Development

The Myd88^fl allele was designed by Dr. Anthony L. DeFranco (University of California San Francisco) to have loxP sites flanking exon 3 of the myeloid differentiation primary response gene 88 (Myd88) on chromosome 9. Specifically, the targeting vector placed a frt-flanked neomycin resistance cassette and loxP site upstream of exon 3, and a second loxP site just downstream of exon 3 of the myeloid differentiation primary response gene 88 locus (Myd88) on chromosome 9. The construct was electroporated into 129P2/OlaHsd-derived E14 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts. Chimeric animals were bred with Actin-FLPe mice (on a C57BL/6 congenic background; see Stock No. 005703) to achieve germline transmission and to remove the neo cassette. The resulting Myd88^fl mice (retaining the loxP site flanked exon 3 and a single residual frt site) were then backcrossed to C57BL/6J for 11 generations (and the Flpe-expressing transgene was removed) prior to sending heterozygous males with black coat color to The Jackson Laboratory Repository in 2009. 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: Myd88^tm1Defr
Name: targeted mutation 1, Anthony L DeFranco
MGI accession ID: MGI:3809600
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Myd88
Marker name: myeloid differentiation primary response gene 88
Chromosome: 9
Strain of origin: 129P2/OlaHsd
Molecular note: Exon 3 was flanked by loxP sites by placing a FRT-flanked neo-cassette with a 3' loxP site upstream of exon 3 with an additional loxP site being placed downstream of exon 3. Founders were crossed with ACTB-FLPe mice to remove the neo selection cassette. Expression levels of Myd88 were unaffected by loxP insertion. Cre-recombination is predicted to excise exon 3 and create a null allele.