Infertile female Zp2 knock-out mice exhibit an abnormal zona matrix with a thin zona matrix present in early follicles but not sustained in pre-ovulatory follicles.
Jurrien Dean, NIH / NIDDK
Mice that are homozygous null for the Zp2 gene are viable, normal in size and do not display any gross physical abnormalities. No Zp2 gene protein product is immunodetectable in ovary tissue. Although the ovaries appear normal with follicles at all stages of development present, homozygous females are infertile. A thin zona matrix is present in early follicles but is not sustained in pre-ovulatory follicles. The abnormal zona matrix does not affect initial folliculogenesis, but there is a significant decrease in the number of antral stage follicles in ovaries isolated from mice lacking a zona pellucida. Few eggs are detected in the oviduct after stimulation with gonadotropins, and no two-cell embryos are recovered after mating Zp2-null females with normal male mice. Although zona-free oocytes mature and can be fertilized in vitro and successfully progress to the blastocyst stage, the developmental potential of blastocysts derived from homozygous Zp2-null eggs appears compromised. The donating investigator has not observed live births when fertilized null eggs are transferred to foster mothers. Male homozygotes are fertile and phenotypically normal.
A targeting vector containing neomycin resistance and herpes simplex virus thymidine kinase genes was used to disrupt a 5' region of the Zp2 gene (exons 1-2). The construct was electroporated into 129X1/SvJ x 129S1/Sv-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6N blastocysts. The resulting chimeric animals were crossed to outbred CF1 mice.
|Allele Name||targeted mutation 1, Jurrien Dean|
|Allele Type||Targeted (Null/Knockout)|
|Allele Synonym(s)||Zp2tm; Zp2tm1Nih; Zp2tm2Nih|
|Gene Symbol and Name||Zp2, zona pellucida glycoprotein 2|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||Part of exon 1 and exon 2 were replaced by a neomycin cassette. Absence of the protein was confirmed by immunohistochemistry on ovarian sections of mutant female mice.|
|Mutations Made By|| |
Jurrien Dean, NIH / NIDDK
This strain originated on a B6;129 background and was crossed to outbred CF1 mice. When held in a live colony, they may be maintained by crossing homozygous males with heterozygous females.
When using the Zp2 KO mouse strain in a publication, please cite the originating article(s) and include JAX stock #004129 in your Materials and Methods section.