SHIP-/- KO mice lack 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
SHIP-/- KO mice lack the promoter and exon 1 of the inositol polyphosphate-5-phosphatase D Inpp5d gene, abolishing gene expression. 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. Heterozygous mice are viable and fertile, while homozygous mice die between 7-12 weeks of age. Mice show a 20-fold increase in the numbers of Mac-1+Gr-1+ myeloid suppressor cells and other myelogranulocytic cell types in the spleen and lymph node. They have an increase in CD11c-Mac-1+ monocytes and CD11c+Mac-1+ dendritic cells in spleen, with only an increase in monocytes seen in the spleen. Numbers of Natural Killer (NK) cells in these mice are increased, and have abnormal cell surface markers, with increases in NK receptor, Klrb1c (NK1.1). They also have altered expression of MHC receptors. These NK cells survive longer than those in controls. SHIP- mice fail to reject fully mismatched allogeneic marrow grafts and show enhanced survival after such transplants.
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 SHIPfloxchimeric males were bred with C57BL/6J females. These floxed mice are available at The Jackson Laboratory as Stock No. 028255.
Upon arrival at The Jackson Laboratory Repository, a subset of the floxed mice were bred to B6.C-Tg(CMV-cre)1Cgn/J mice (Stock No. 006054) to delete the promoter and exon 1 to establish this colony of SHIP-/- mice.
|Allele Name||targeted mutation 1.1, William G Kerr|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Inpp5d, inositol polyphosphate-5-phosphatase D|
|Strain of Origin||129S6/SvEvTac|
|Molecular Note||Crossing with cre deleter mice excised the floxed region containing the promoter and exon 1. Western blot of spleen whole cell lysates demonstrated a lack of protein in mutants.|
When maintaining a live colony, heterozygous may be bred to wildtype (non-carrier) mice from the colony. Homozygous mice die between 7-12 weeks of age.
When using the SHIP- mouse strain in a publication, please cite the originating article(s) and include JAX stock #028269 in your Materials and Methods section.