Oocyte growth and follicular development in KIT-deficient Fas-knockout mice.
In mammals, oocyte growth and follicular development are known to be regulated by KIT, a tyrosine kinase receptor. Fas is a member of the death receptor family inducing apoptosis. Here, we investigated germ cell survival, oocyte growth and follicular development in KIT-deficient (Wv/Wv:Fas+/+), Fas-deficient (+/+:Fas-/-), and both KIT- and Fas-deficient (Wv/Wv:Fas-/-) mice during fetal and postnatal periods. Further, the ovaries of these mice were transplanted in immunodeficient mice to compare oocyte growth and follicular development under a condition isolated from the extraovarian effects of KIT- and Fas-deficiency. Higher numbers of germ cells were found in the fetal and postnatal ovaries of Fas-deficient mice than in the same-aged wild-type mice. In KIT-deficient mice, ovaries at 13 days postcoitum (dpc) contained 1106+/-72 (n=3) germ cells, but the ovaries contained no oocytes after birth. Twenty-one days after transplantation of the ovaries at 13 dpc, no oocytes/germ cells were found. A higher number of germ cells (3843+/-108; n=3) were observed in the Wv/Wv:Fas-/- genotypes than in Wv/Wv:Fas+/+ mice at 13 dpc. Furthermore, Wv/Wv:Fas-/- mice contained 528+/-91 (n=3) oocytes at 2 days, and follicles developed to the antral stage at 14 days of age. After transplantation of fetal and neonatal ovaries from Wv/Wv:Fas-/- mice, increased numbers of growing oocytes and developing follicles were obtained compared with those in 14-day old ovaries in vivo. These results show that oocytes grow and follicles develop without KIT signaling, although KIT might be essential for the survival of germ cells/oocytes in mice.
Moniruzzaman
Mohammad
M
Graduate School of Science and Technology, Kobe University, Kobe 657-8501, Japan. 026d910n@stu.kobe-u.ac.jp
Sakamaki
Kazuhiro
K
Akazawa
Yukiko
Y
Miyano
Takashi
T
D000818:Animals; D000831:Animals, Newborn; D002452:Cell Count; D002470:Cell Survival; D053222:Fas Ligand Protein / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005838:Genotype; D051379:Mice; D018345:Mice, Knockout; D009865:Oocytes / Q000166:cytology*; D006080:Ovarian Follicle / Q000196:embryology / Q000502:physiology*; D010053:Ovary / Q000637:transplantation; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism*; D012879:Skin Physiological Phenomena
D053222:Fas Ligand Protein; D019009:Proto-Oncogene Proteins c-kit