| Budget Amount *help |
¥28,990,000 (Direct Cost: ¥22,300,000、Indirect Cost: ¥6,690,000)
Fiscal Year 2011: ¥9,100,000 (Direct Cost: ¥7,000,000、Indirect Cost: ¥2,100,000)
Fiscal Year 2010: ¥9,880,000 (Direct Cost: ¥7,600,000、Indirect Cost: ¥2,280,000)
Fiscal Year 2009: ¥10,010,000 (Direct Cost: ¥7,700,000、Indirect Cost: ¥2,310,000)
|
|---|
| Research Abstract |
Although neonatal mammalian ovaries contain many nongrowing primordial oocytes, most degenerate and only a few contribute to the oocyte pool in the mature ovary. If these arrested neonatal primordial oocytes could be rescued effectively, they would form a potentially valuable source for research, clinical, and zoological purposes. In this research, we developed a follicle-free culture system that enables a large number of arrested oocytes to develop in vitro. By selective culture of ovarian cells from newborn (2-4 days old) mice, spherical colonies consisting exclusively of primordial oocytes and putative thecal stem cells were obtained. Upon treatment with a stem cell factor (c-kit ligand), these embedded oocytes were released from the colonies. The released oocytes-more than 800 per animal-continued to develop without any supporting cells, formed a zona pellucida, and were able to fuse with spermatozoa. This culture system provides a unique experimental model for studying the mechanisms of oogenesis, as it can supply many granulosa cell-free oocytes at specific stages. We successfully generated MII oocytes using ectopic transplantation method that was constructed by in vitro cultured oocytes and neonatal ovarian somatic cells. Furthermore, we noticed a novel oocyte apoptosis mechanism which is controlled by oocyte autonomously.
|
