Analysis of novel protein complexes that regulate Polycomb silencing

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K07451
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Genetics/Chromosome dynamics
• Research Institution: Saga University
• Principal Investigator: NISHIOKA KENICHI 佐賀大学, 医学部, 客員研究員 (80370120)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: エピゲノム制御 / ポリコームサイレンシング / Mbf1 / Pacman

Outline of Final Research Achievements

Several candidate genes for Polycomb silencing regulators have been identified in previous our study.
Mbf1, known as a nuclear coactivator that regulates stress response genes, is localized mainly in cytoplasm although function of cytoplasmic Mbf1 is not known. The cytoplasmic Mbf1 binds to E(z) mRNA encoding a catalytic subunit of PRC2, thereby protecting the mRNA from the attack by Pacman, 5'-to-3' exoribonuclease, and which contribute to maintain robustness of Polycomb silencing. Mbf1 also binds to mRNAs derived from many stress response genes. Our study elucidates a unique feature of Mbf1 in that Mbf1 demonstrates different biochemical activity according to its subcellular localization although both activities contribute a similar biological function.

Free Research Field

エピゲノム制御

Academic Significance and Societal Importance of the Research Achievements

Mbf1はこれまでストレス関連遺伝子を活性化する核内コアクチベーターとして知られていたが、主な局在である細胞質における機能は分かっていなかった。 一方で、Pacmanが絡む5'側のRNA分解制御メカニズムについてはこれまでほとんどわかっていなかった。もうすこし詳細な生化学的実験が必要であるが、当該制御メカニズムについて新たな知見が得られたこととなる。また、本論文の報告をもって遺伝子スクリーニング方法の妥当性を証明できたことも特筆すべき点で ある。