These mice carry a targeted knockout of the Stra8 (stimulated by retinoic acid gene 8) gene on a C57BL/6 genetic background. Both male and female homozygous knockout mice are infertile as germ cells fail to initiate meiosis.
David Page, Whitehead Institute for Biomedical Research
The mouse Stra8 (stimulated by retinoic acid gene 8) gene is expressed exclusively in premeiotic germ cells in both males and females. In females, it is expressed in the embryonic ovary. In males, it is expressed in pubertal and adult testes, in pre-meiotic spermatogenic cells.
These mice carry a targeted knockout of the Stra8 gene on a C57BL/6N genetic background. Exons 2-7 were replaced with an IRES-LacZ/pgk-Neo cassette which is transcribed, but may not produce protein. Both male and female homozygous knockout mice are infertile as germ cells fail to initiate meiosis. STRA8 expression is not detectable by immunohistochemistry or by RT-PCR from homozygous adult testes or fetal ovaries. The phenotype is very sensitive to strain background (particluarly for the males).
A 7.8 kb region containing a portion of exons 2, and exons 3-7 was replaced with an IRES-LacZ/pgk-Neo cassette through homologous recombination in (C57BL/6 x 129S4/SvJae)F1-derived V6.5 embryonic stem (ES) cells. This strain was backcrossed to C57BL/6NTac for 26 generations by the donating laboratory (see SNP results below). Upon arrival at The Jackson Laboratory, this strain was rederived using C57BL/6NJ (see Stock No. 005304).
In 2014, a 32 SNP (single nucleotide polymorphism) panel analysis, with 27 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the first generation rederived living colony at The Jackson Laboratory Repository. While the 27 markers throughout the genome suggested a C57BL/6 genetic background, all 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating in all mice. These data suggest that the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J genetic background.
|Allele Name||targeted mutation 1, David C Page|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Stra8, stimulated by retinoic acid gene 8|
|Strain of Origin||(C57BL/6 x 129S4/SvJae)F1|
|Molecular Note||An IRES-lacZ-neocassette was inserted into exon 2, replacing exons 3-6 and part of exon 7.|
Heterozygous mice are viable and fertile, but some males are poor breeders. Both female and male homozygotes are infertile due to a failure of germ cells to initiate meiosis.
When using the B6.Cg-Stra8tm1Dcp/J mouse strain in a publication, please cite the originating article(s) and include JAX stock #023805 in your Materials and Methods section.