The Pld2- null allele has exons 13-15 (including the catalytic activity-dependent first HKD motif) of the phospholipase D2 gene deleted. These mice may be useful in studying membrane trafficking, membrane fusion, cancer, neurodegeneration and Alzheimer's disease.
Gilbert Di Paolo, Columbia University Medical Center
Phospholipase D2 (Pld2) and its related isoform phospholipase D1 (Pld1) hydrolyze phosphatidylcholine to generate bioactive lipid phosphatidic acid (PA), are implicated in membrane trafficking/membrane fusion, and are elevated/up-regulated in various human cancers.
The Pld2- null allele has exons 13-15 (including the catalytic activity-dependent first HKD motif) of the phospholipase D2 gene deleted. Homozygous mice are viable and fertile with no reported abnormalities. No protein expression from the knockout allele is detected by western blot analysis of homozygous brain tissue.
To study the effect of PLD2-deficiency on Alzheimer's disease, the Pld2- animals can be bred to
have a transgene expressing the human APP with Familial Alzheimer's Disease Swedish mutations K670N/M671L. The resulting PLD2-deficient APPSw transgenic mice exhibit reduced Alzheimer's disease characteristics (amyloid-beta-induced synaptic dysfunction and cognitive deficits).
In addition, on a C57BL/6J genetic background, PLD2 ablation does not significantly reduce intestinal tumorigenesis in the ApcMin model (Stock No. 002020). This is contrary to the protective effect observed for deficiency of the related isoform PLD1 (Stock No. 028668) in the C57BL/6J-ApcMin model.
The Pld2- null allele was created by Dr. Gilbert Di Paolo (Columbia University Medical Center). A targeting vector was designed to have a loxP site upstream of exon 13, and a frt-flanked neo cassette with 3' loxP site just downstream of exon 15 of the phospholipase D2 gene (Pld2) on chromosome 11. The construct was electroporated into C57BL/6 x 129/SvJ embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts, and chimeric males were bred with C57BL/6J females to establish the Pld2Flox Neo colony. The mice were then bred to the C57BL/6J-congenic FLP deleter strain (Stock No. 005703) for germline removal of the frt-flanked neo. The resulting Pld2Flox colony was backcrossed to C57BL/6J wildtype mice for several generations (and the Flp-expressing transgene was removed). The donating investigator reports that mice were bred with the C57BL/6-congenic Cre deleter strain (Stock No. 003724) for germline deletion of the floxed sequences (exons 13-15 and single frt site); creating the Pld2- null allele. The Pld2- colony had been backcrossed to C57BL/6J a total of ten generations (and the cre-expressing transgene was removed) prior to sending males with black coat color to The Jackson Laboratory Repository in 2016. 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).
Of note, the donating investigator reports that, at least once during backcrossing, a heterozygous female was bred to a C57BL/6J inbred male (thus the Y chromosome of the congenic strain is of C57BL/6J origin).
|Allele Name||targeted mutation 1.1, Gilbert Di Paolo|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Pld2, phospholipase D2|
|Strain of Origin||C57BL/6 x 129/SvJ|
|Molecular Note||A loxP site was inserted upstream of exon 13, and an FRT-flanked neo cassette with a 3' loxP site was inserted downstream of exon 15. This allele is created by using either Cre-mediated recombination to remove exons 13-15 and the selection cassette or Flp-mediated recombination to remove the FRT-flanked neo cassette, followed by Cre-mediated recombination to remove exons 13 to 15. The reduction in protein expression was confirmed by western blot analysis.|
Mice homozygous for Pld2Flox are viable and fertile with no reported abnormalities. When maintaining a live colony, heterozygous mice may be bred together, to wildtype mice from the colony or to C57BL/6J inbred mice (Stock No. 000664). Alternatively, homozygous mice may be bred together.
When using the Pld2- mouse strain in a publication, please cite the originating article(s) and include JAX stock #028668 in your Materials and Methods section.