L1調節器の全ゲノムスクリーンで明らかにされたエウクロマティックL1の選択的な静止
Nian Liu1, Cameron H Lee2, Tomek Swigut1
1Department of Chemical and Systems Biology, Stanford School of Medicine, Stanford University, Stanford, California 94305, USA.
Nature
|December 7, 2017
まとめ
LINE-1 (L1) のような移植可能な要素は,ゲノム進化と病気に影響を与えます. この研究では,L1の活動を制御する遺伝子を特定し,HUSHとMORC2がL1をエピジェネティックに静止させ,宿主遺伝子の発現を変更する新しい経路を明らかにしました.
科学分野:
- 遺伝学
- エピジェネティクス
- 分子生物学
背景:
- 移植可能な元素,特に長間隔の元素-1 (LINE-1またはL1) は,ゲノム進化に影響を与え,病気を引き起こす移動性遺伝子配列である.
- L1sは遺伝子変異に不可欠ですが,宿主遺伝子発現における正確な調節と役割は完全に理解されていません.
研究 の 目的:
- CRISPR-Cas9を使用してLINE-1 (L1) リトロトランスポーゼーションを調節する遺伝子を識別する全ゲノムスクリーンを実施する.
- MORC2とHUSH複合体を含む特定の要因がL1活動を制限するメカニズムを解明する.
- エピジェネティック・モディファイヤーによるL1サイレンシングが宿主遺伝子の発現にどのように影響するかを調査する.
主な方法:
- ヒト細胞系における全ゲノムCRISPR-Cas9スクリーニングで,L1逆転移の調節体を特定する.
- MORC2とHUSH複合体のサブユニット (MPP8,TASOR) とL1要素の相互作用を調査する.
- ヒストン改変 (H3K9me3) と宿主遺伝子発現に対するL1サイレンスの影響の評価.
主要な成果:
- L1の逆転を促すか抑制する様々な遺伝子の特定が,しばしばヒトの病気と関連している.
- HUSH複合体とMORC2が,ユークロマチン内の若くて長身のL1を選択的に結合することを発見した.
- HUSHとMORC2がH3K9me3の沈殿を促進し,近くの宿主遺伝子をダウンレギュレーションする.
結論:
- HUSHとMORC2を含む新しいL1制限経路が解明され,トランポゾンに対する表遺伝的制御が強調された.
- 宿主遺伝子の内にある L1 サイレンシングは遺伝子発現プログラムを再構築し,トランポゾンとゲノムの複雑な相互作用を強調します.
- この研究は,L1逆転とゲノム調節と疾患におけるその影響を理解するための貴重なリソースを提供します.
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