These Csf1rfl/fl floxed mutant mice possess loxP sites flanking exon 5 of the colony stimulating factor 1 receptor (Csf1r) gene and may be useful in studying the role of CSF1R in development.
Jeffrey W Pollard, Albert Einstein College of Medicine
These Csf1rfl/fl floxed mutant mice possess loxP sites flanking exon 5 of the colony stimulating factor 1 receptor (Csf1r) gene. Csf1r encodes Cd115 which acts as the receptor for colony stimulating factor 1, a cytokine which controls the production, differentiation, and function of macrophages. Expressed in macrophages, expression is also seen in oocytes, osteoclasts, trophoblasts, CNS microglia, and some myoblasts. Mice that are homozygous for this allele are viable and fertile. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exon 5 and the neo cassette deleted in cre-expressing tissues.
For example, when crossed to B6.Cg-Tg(Nes-cre)1Kln/J mice ( Stock No. 003771), expressing Cre recombinase in the neural progenitors, resulting offspring exhibit smaller
brain size, an expanded neural progenitor pool and elevated cellular apoptosis in cortical forebrain.
When crossed to B6.FVB-Tg(Zp3-cre)3Mrt/J mice (Stock No. 003394), expressing Cre recombinase in the female germ line, resulting offspring exhibit premature death by 6 weeks of age, smaller body size, and osteoporosis. Offspring also lack teeth.
A targeting vector was designed to insert a single loxP site upstream of exon 5, and a loxP-flanked neomycin resistance (neo) cassette downstream of exon 5 of the colony stimulating factor 1 receptor (Csf1r) gene. The construct was electroporated into STOCK (129/Sv and C57BL/6J and SJL)-derived WW6 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts and resulting chimeric males were bred with C57BL/6J females. Mice were crossed to a cre-expressing line to remoce the neo cassette, and resulting offspring were crossed to remove the cre-expressing transgene. These Csf1rfl/fl mice were bred to C57BL/6J mice for at least 15 generations. Upon arrival, mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.
|Allele Name||targeted mutation 1.2, Jeffrey W Pollard|
|Allele Type||Targeted (Conditional ready (e.g. floxed))|
|Gene Symbol and Name||Csf1r, colony stimulating factor 1 receptor|
|Strain of Origin||STOCK 129/Sv and C57BL/6J and SJL|
|Molecular Note||A targeting vector was designed to insert a single loxP site upstream of exon 5, and a loxP-flanked neomycin resistance (neo) cassette downstream of exon 5. Cre-mediated recombination removed the neo cassette leaving exon 5 floxed.|
When maintaining a live colony mice homozygous for the floxed allele may be bred together.
When using the Csf1rflox mouse strain in a publication, please cite the originating article(s) and include JAX stock #021212 in your Materials and Methods section.