Bone morphogenetic protein 8B (BMPBB) is a member of the TGF beta superfamily of growth factors. In the mouse Bmp8b is expressed in male germ cells of the testis and trophoblast cells of the placenta. Homozygous Bmp8btm1Blh mutant males exhibit variable degrees of germ-cell deficiency and infertility. Germ cells of all homozygous mutants either fail to proliferate or show a marked reduction in proliferation and a delayed differentiation during early puberty (2 weeks old or younger). There is a significant increase in apoptosis of spermatocytes, leading to germ-cell depletion and sterility. Sertoli cells and Leydig cells appear relatively unaffected in adult mutants.
The tm1Blh targeted mutation of Bmp8b was generated in a 129-derived embryonic stem cell in the laboratory of Dr. Brigit Hogan. Bmp8btm1Blh on a mixed 129 x Black Swiss background was imported into the laboratory of Dr. Eva Eicher at The Jackson Laboratory where it was backcrossed once to C57BL/6J females then backcrossed onto the C57BL/6JEi background until N12. In 2004 embryos were cryopreserved from in vitro fertilization of C57BL/6J females and N12 heterozygous males.
|Allele Name||targeted mutation 1, Brigid L Hogan|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Bmp8b, bone morphogenetic protein 8b|
|Strain of Origin||129/Sv|
|General Note||ES cell line = R1 ((129X1/SvJ x 129S1/Sv)F1-Kitl+) or TL1 (129S6/SvEvTac).|
|Molecular Note||A 7 kb genomic fragment containing exon 4 was replaced with a neomycin selection cassette. The deleted sequences encode the conserved dibasic proteolytic cleavage site between the pro- and mature regions of the encoded protein. In situ hybridization experiments on sections of testis of homozygous male mice confirmed that no detectable transcript was produced from this allele.|
When using the B6 x B6Ei.129(Cg)-Bmp8btm1Blh/EiJ mouse strain in a publication, please cite the originating article(s) and include JAX stock #005032 in your Materials and Methods section.