Elucidation of oocyte molecular mechanism on imprinted X chromosome inactivation enabling a sequential development

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H01588
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Obstetrics and gynecology
• Research Institution: National Center for Child Health and Development
• Principal Investigator: Akutsu Hidenori 国立研究開発法人国立成育医療研究センター, 生殖医療研究部, 部長 (50347225)
• Co-Investigator(Kenkyū-buntansha): 中林 一彦 国立研究開発法人国立成育医療研究センター, 周産期病態研究部, 室長 (10415557) ; 佐渡 敬 近畿大学, 農学部, 教授 (70321601)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: Xist / Oct4 / 初期胚

Outline of Final Research Achievements

During oocyte maturation, the chromatin is condensed, but after fertilization, the chromatin becomes asymmetric condensing. At the early blastocyst stage, each allylic chromatin relaxes and becomes "Neutral" (chromatin initialization). Subsequently, it has been shown that although placental development takes the form of asymmetric chromatin, random inactivation of the X chromosome occurs in ontogenetic systems under the condensation of random chromatin of both sexes during the peri-implantation periods. Oct4 gene, a pluripotent factor, is responsible for controlling the condensation and relaxation of nuclear chromatin that controls X-chromosome inactivation, and the OCT4 protein acts as a chromatin opener that leads to a relaxed state from chromatin condensation, indicating that the spatiotemporal control of OCT4 is associated with totipotency.

Free Research Field

生殖発生医学

Academic Significance and Societal Importance of the Research Achievements

X染色体不活化は、卵子、初期胚の細胞内動態が胎盤発生と成体健康状態・疾患へ明確に影響するバイオシステムとして研究できる唯一の発生モデルである。着床周辺期までに決定するX染色体不活化分子制御機構を明らかにすることは女性の細胞基本動態を理解することで多領域にわたる女性医学の進展に大きく貢献するものである。