Establishment of novel in vitro systems to produce mammalian oocytes

2017 Fiscal Year Final Research Report

• Project Area: Mechanisms regulating gamete formation in animals
• Project/Area Number: 25114008
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: Tokyo University of Agriculture
• Principal Investigator: Yayoi Obata 東京農業大学, 生命科学部, 教授 (70312907)
• Co-Investigator(Kenkyū-buntansha): 平尾 雄二 国立研究開発法人農業・食品産業技術総合研究機構, 畜産研究部門, ユニット長 (10355349)
• Project Period (FY): 2013-06-28 – 2018-03-31
• Keywords: 卵子形成 / 卵胞形成 / in vitro / 培養

Outline of Final Research Achievements

In this study, we successfully established an in vitro system that produces mature oocytes from mouse primordial germ cells (PGC), for the first time.
The main challenge which we had to overcome was abnormal follicle formation in vitro. To understand the cause of abnormal follicle formation, RNA-seq analysis was conducted in the explants. We found that the estrogen pathway was excessively activated in the cultured ovaries. Therefore, an antagonist of estrogen receptor was added to the medium. This resulted in secondary follicle formation in the cultured ovary. The isolated secondary follicles were cultured in the medium supplemented with macromolecular compounds. Addition of macromolecular compounds to the medium increased the number of matured oocytes. These mature oocytes were able to develop to offspring after fertilization and embryo transfer. In the future, this in vitro system will be useful tools which assist in understanding oogenesis and producing a lot of mammalian oocytes.

Free Research Field

発生工学