Epigenetic regulation during the loss of totipotency

2023 Fiscal Year Final Research Report

• Project Area: Program of totipotency: From decoding to designing
• Project/Area Number: 19H05754
• 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: Institute of Physical and Chemical Research
• Principal Investigator: Inoue Azusa 国立研究開発法人理化学研究所, 生命医科学研究センター, チームリーダー (60814910)
• Co-Investigator(Kenkyū-buntansha): 山口 新平 東邦大学, 理学部, 講師 (80740795)
• Project Period (FY): 2019-06-28 – 2024-03-31
• Keywords: クロマチン / 卵子 / 初期胚

Outline of Final Research Achievements

A single fertilized egg has the ability to differentiate into any cell (totipotency). However, it is not well understood how the molecular program establishes and loses totipotency. In this study, we focused on heterochromatin, which is responsible for opening and closing chromatin, and analyzed the dynamics and function of heterochromatin during oocyte formation and fertilization (establishment of totipotency) and preimplantation development (maintenance and loss of totipotency). As a result, we found that totipotent zygotes and early preimplantation embryos have very unique heterochromatin and that they undergo a stepwise transition towards typical heterochromatin during preimplantation development. Thus, we think the atypical heterochromatin state may underlie totipotency.

Free Research Field

エピジェネティクス

Academic Significance and Societal Importance of the Research Achievements

哺乳類の生命は一つの受精卵から誕生します。その小さな細胞の中で、父親と母親から受け継がれた二つのゲノムが混ざり合い、個体の全ての細胞に分化する能力である「全能性」を獲得します。本研究では、受精卵の元となる卵子の形成過程から、受精、そして初期胚発生の間に、どのように全能性が確立されるのかを解明しました。この成果は今後、細胞に全能性を付与する技術の開発に貢献することが期待されます。