Investigation of negative regulators for proliferation and development of germ cells

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22437
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 44:Biology at cellular to organismal levels, and related fields
• Research Institution: National Institute of Genetics
• Principal Investigator: Sakai Noriyoshi 国立遺伝学研究所, 遺伝形質研究系, 准教授 (50202081)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: 生殖幹細胞 / 組織微小環境 / 全胚移植法 / ゼブラフィッシュ

Outline of Final Research Achievements

To explore intrinsic changes in micro environments of living organs with aging, we analyzed interaction of the heterochronic parabiotic testes after transplantation of whole living larvae as grafts in an immunodeficient adult zebrafish. When we used meioc mutants whose testes have only germ-line stem cells (GSCs) as a host, development of testes in grafted larvae was not affected, but GSCs of the host decreased. This result showed a possibility that factors that depend on differentiating germ cells suppress proliferation of GSCs. In addition, we developed transplantation experiments using ovarian germ cell aggregates to explore interaction between oocytes and GSCs.

Free Research Field

生殖生物学

Academic Significance and Societal Importance of the Research Achievements

生体組織は胚性期に未分化細胞により器官原器が形成され、成長過程を経て最終的な成体の組織へと成熟する。成体組織は少数の成体幹細胞と多数の分化型細胞により構成され、胚性期の未分化細胞により構成される器官原器とは、その微小環境も質的に異なるものと予想されるが、その実体はほとんどわかっていない。本課題の成体幹細胞の増殖を負に制御する因子もまだ見つけられていない要素で、その発見は成体組織の幹細胞維持システムに新たな概念をもたらすことが期待される。