プリオン エピジェネティック スイッチ が 活性 クロマチン 状態 を 確立 する
Zachary H Harvey1, Anupam K Chakravarty1, Raymond A Futia2
1Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Cell
|February 29, 2020
まとめ
新しく発見されたプリオン[ESI+]は 活性化クロマチンの状態を世代を超えて 継承することを可能にします このプリオンはヒストン脱酸化活性を再構成し 遺伝子を活性化し ストレス抵抗性を引き出します
科学分野:
- エピジェネティクスとクロマチン生物学
- 分子遺伝学
- 細胞 の ストレス 反応
背景:
- ヒストンの改変は,発達中の機能的な染色体領域の確立に不可欠である.
- 抑制されたクロマチンの遺伝はよく知られていますが,活性化されたクロマチンの遺伝のメカニズムは欠けています.
研究 の 目的:
- 活性化クロマチン状態の世代間遺伝の背後にあるメカニズムを調査する.
- 遺伝子発現パターンの遺伝を促進する要因を特定する.
主な方法:
- ヒストン変異とクロマチンの状態を研究するために酵母モデルを使用した.
- Set3Cヒストン脱エチラゼ基板Snt1の役割を調査した.
- [ESI+]と呼ばれる新種のプリオンと,その遺伝子の活性化への影響を特徴づけた.
主要な成果:
- 活性化クロマチンの出現と遺伝を駆動するプリオンとしてSnt1を特定した.
- [ESI+]は細胞サイクル停止時にSnt1のリン酸化によって誘発される.
- [ESI+]はSnt1の活性を再構成し 遺伝子の活性化と環境ストレスへの耐性を引き起こすことが示されました
結論:
- 活性化クロマチンの状態の継承のための新しいプリオンベースのメカニズムを確立した.
- [ESI+]は,世代を超えた表遺伝子遺伝による適応的な利点を提供する役割を強調した.
- エピジェネティックな記憶と 進化におけるその役割を理解するための 新たな道を開きました
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