第762回 生医研セミナー(多階層生体防御システム研究拠点)


下記の通り、石黒 啓一郎 先生によるセミナーを開催致します。皆様方のご参加を心よりお待ちしております。

※セミナーは英語で行われます。(Seminar in English)

演題 / Title

A novel nuclear factor plays a crucial role in initiation of meiosis

演者 / Speaker

石黒 啓一郎 先生
熊本大学発生医学研究所 染色体制御分野 准教授
Associate Prof. Kei-ichiro Ishiguro
Institute of Molecular Embryology and Genetics, Kumamoto University

日時 / Date

2018年1月17日(水)  Jan. 17 (Wed), 2018
16:00~17:00

場所 / Venue

病院キャンパス 生体防御医学研究所 本館1階 会議室
以下の地図の26番です。
(http://www.kyushu-u.ac.jp/f/30078/Hospital_jp-2017.pdf)

Seminar Room, Main Building 1F, Medical Institute of Bioregulation
No.26 on the following linked map.
(http://www.kyushu-u.ac.jp/f/30074/Hospital_en-2017.pdf)

要 旨 / Abstract

The switching from mitotic to meiotic cell cycle is a crucial step for reorganization of meiotic chromosome1, 2 in gametogenesis. In mammals, Stimulated by retinoic acid 8 (STRA8) is required for induction of meiosis. Although the significance of STRA8 in initiating meiosis is recognized, the underlying mechanism how STRA8 involves in meiotic initiation has been largely elusive. To elucidate the molecular mechanisms of meiotic initiation, we purified STRA8 protein complex from testes of the genetically engineered STRA8 knockin mice. Mass-spectrometric analysis identified novel factors that are associated with STRA8. Notably, StIP1 (Stra8 interacting protein-1), which is encoded by a previously uncharacterized hypothetical gene, shows germ cell specific expression patterns in both male and female germ cells. Immuno-fluorescent analysis shows that StIP1 protein is co-expressed with STRA8 in a limited population of pre-meiotic germ cells in male and female. Importantly, despite of STRA8 expression, initiation of meiosis is abolished in StIP1 KO mice. Remarkably, expression of meiotic prophase genes is largely impaired in the absence of StIP1, accounting for severe arrest of germ cells before meiosis. These results suggest that StIP1 together with STRA8 plays a crucial role in initiation of meiosis.
Here, we discuss our latest unpublished data on the issues of meiotic initiation and the consequent chromosome reorganization.

業 績 / Publications

Ishiguro, K. et al. Meiosis-specific cohesin mediates homolog recognition in mouse spermatocytes. Genes & Dev. 28, 594-607 (2014)
Kim J, Ishiguro K. et al. Meikin is a conserved regulator of meiosis I specific kinetochore function. Nature 517, 466-471 (2015)

連絡先 / Contact

生体防御医学研究所 エピゲノム制御学分野
佐々木 裕之 092(642)6759

Division of Epigenomics and Development, MIB, Hiroyuki SASAKI
Tel:092-642-6759