Development of Retrotransposon Expression Control for High-Efficiency In Vitro Spermatogenesi

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K21657
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 56:Surgery related to the biological and sensory functions and related fields
• Research Institution: Yokohama City University
• Principal Investigator: SATO Takuya 横浜市立大学, 医学部, 講師 (70599505)
• Co-Investigator(Kenkyū-buntansha): 古目谷 暢 横浜市立大学, 医学部, 助教 (60721082)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: 精子形成 / 精巣 / レトロトランスポゾン / 逆転写酵素阻害剤

Outline of Final Research Achievements

By organ culturing neonatal mouse testes, it has become possible to induce differentiation of spermatogonial stem cells into sperm. However, inducing spermatogenesis in vitro from more immature fetal testes (Embryonic day 12.5) has been challenging. In this study, we achieved, for the first time, the induction of differentiation up to round spermatids and elongating spermatids by organ culturing fetal testes in a medium supplemented with a reverse transcriptase inhibitor. Furthermore, to confirm the normality of these spermatid cells, we conducted microinsemination experiments and successfully obtained healthy offspring. These results demonstrate the successful progression of in vitro spermatogenesis in fetal testes.

Free Research Field

発生生物学

Academic Significance and Societal Importance of the Research Achievements

本研究により、逆転写酵素阻害剤が体外精子形成の誘導効率を改善することがあきらかとなり、新たに胎仔期精巣の培養法を確立することができた。これによって胎仔期精巣の発達から出生後の精子形成の開始、精子完成にいたる過程が体外で解析が可能になった。本研究において開発した胎仔精巣の培養は、胎仔期の精巣発生モデルとして、 発生学的な観点から新たな情報を提供できることが期待される。