These Kitl mutant mice carry a floxed exon which, when excised through a cross with a cre strain, enables tissue-specific disruption of gene expression.
Sean J Morrison, University of Texas Southwestern Medical Center
These mice possess loxP sites on either side of exon 1 of the Kitl (kit ligand; also called Scf, stem cell factor) gene. Mice that are homozygous for this allele are viable and fertile with no observed abnormalities. When these mutant mice are bred to mice that express Cre recombinase, the resulting offspring will have exon 1 deleted in cre-expressing tissues.
Mice generated from a cross of these mice with Ubc-creER animals (e.g. Stock No. 008085) can be treated with tamoxifen to induce widespread deletion of the floxed segment. These mice become anemic and show significantly lower red blood cell counts, trend towards lower white blood cell and pletelet counts, and exhibit approximately twofold reductions in the overall cellularity of bone marrow and spleen.
A loxP site was introduced 5' of exon 1 and an Frt-Neo-Frt-loxP cassette was placed 3' of exon 1 in sites that do not disrupt regulatory elements of the targeted gene. C57BL/6-derived Bruce 4 G9 embryonic stem (ES) cells were used to create the mutation. Chimeric mice were bred with C57BL/6-Tyrc-2J mice to obtain germline transmission. Animals were then crossed with C57BL/Ka background Flp-expressing mice to excise the neomycin cassette, leaving exon 1 flanked by loxP sites. This strain was backcrossed to C57BL/Ka for six generations by the donating laboratory. Upon arrival at The Jackson Laboratory, C57BL/6J was used for rederivation.
|Allele Name||targeted mutation 2.1, Sean J Morrison|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Kitl, kit ligand|
|Strain of Origin||B6.Cg-Thy1a|
|Molecular Note||An FRT-flanked neo cassette with loxP site was inserted downstream of exon 1 and an additional loxP site was inserted upstream of exon 1. The neo cassette was removed by flp-mediated recombination.|
|Mutations Made By|| |
Sean Morrison, University of Texas Southwestern Medical Center
Both heterozygotes and homozygotes are viable and fertile.
When using the Scf (Kitl) floxed mouse strain in a publication, please cite the originating article(s) and include JAX stock #017861 in your Materials and Methods section.