SHIPflox mice possess loxP sites flanking the promoter and exon 1 of the Inpp5d gene making them useful for studying survival signaling pathways in hematopoietic cell lineages.
William G. Kerr, SUNY Upstate Medical University
SHIPflox mice possess loxP sites flanking the promoter and exon 1 of the inositol polyphosphate-5-phosphatase D Inpp5d gene. Mice that are homozygous for this allele are viable and fertile. SHIP is a signaling phosphatase that acts as a mediator of survival signals in a hematopoietic lineage. It has also been implicated in limiting the success of allogeneic marrow transplantation by playing a role in graft rejection and graft-versus-host disease. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have the promoter and exon 1 deleted in cre-expressing tissues.
For example, when crossed to B6.129P2-Lyz2tm1(cre)Ifo/J mice (Stock No. 004781) expressing Cre recombinase in myeloid cell lineages, resulting LysCreSHIPflox/flox mice show expansion of both myeloid-derived suppressor cell (MDSC) and SHIP-competent FoxP3+ T cells in both the spleen and lymph nodes.
A targeting vector was designed by Dr William Kerr to insert a single loxP site upstream of exon 1, containing the promoter, and a loxP-flanked neomycin resistance (neo) cassette downstream of exon 1 of the inositol polyphosphate-5-phosphatase D (Inpp5d) gene. The construct was electroporated into 129S6/SvEvTac-derived TL1 embryonic stem (ES) cells. Correctly targeted ES cells were transiently transfected with a Cre Recombinase expression plasmid to delete the neo cassette. Resulting ES cells contained multiple gene rearrangments; intact floxed-exon 1, intact floxed-neo cassette, or excision of both exon 1 and the neo cassette. Correctly targeted ES cells, containing only the floxed-exon 1, were injected into blastocysts and resulting chimeric males were bred with C57BL/6J females. Resulting offspring were backcrossed to C57BL/6J mice for at least 10 generations to establish a colony of SHIPflox mice. Upon arrival at The Jackson Laboratory Repository, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).
|Allele Name||targeted mutation 1, William G Kerr|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Inpp5d, inositol polyphosphate-5-phosphatase D|
|Strain of Origin||129S6/SvEvTac|
|Molecular Note||A loxP site was inserted upstream of exon 1 and a floxed neomycin cassette was placed downstream of exon 1. Cre recombinase was transiently expressed in correctly targeted ES cells to remove the neomycin selection cassette, leaving exon 1 flanked by loxP sites. Genomic PCR and Southern blotting confirmed removal of the neo cassette and the flox-state of exon 1.|
When maintaining a live colony mice homozygous for the floxed allele may be bred together.
When using the SHIPflox mouse strain in a publication, please cite the originating article(s) and include JAX stock #028255 in your Materials and Methods section.