マイクロRNA-145はOCT4,SOX2,KLF4を調節し,ヒト胚性幹細胞の多能性を抑制する
Na Xu1, Thales Papagiannakopoulos, Guangjin Pan
1Neuroscience Research Institute, Department of Molecular, Cellular, and Developmental Biology, The University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
Cell
|May 5, 2009
まとめ
マイクロRNA-145 (miR-145) レベルは,ヒト胚性幹細胞の分化中に上昇し,OCT4,SOX2,KLF4をターゲットにすることで自己更新を抑制します. これは,幹細胞の発達に不可欠なフィードバックループを明らかにしています.
科学分野:
- 発達生物学 発達生物学について
- 分子生物学は分子生物学である.
- 幹細胞生物学 幹細胞生物学
背景:
- マイクロRNA (miRNA) は,発達に影響を与える遺伝子発現の重要な調節体である.
- 人間の胚性幹細胞 (hESC) は,自己再生と分化能力を持っています.
- 多能性因子であるOCT4,SOX2,KLF4は,hESCの自己更新を維持するために重要である.
研究 の 目的:
- hESCの自己再生と分化におけるmicroRNA-145 (miR-145) の役割を調査する.
- hESCにおけるmiR-145の直接標的を特定する.
- miR-145とコアプルリポテンシー因子との規制関係を解明する.
主な方法:
- hESCの微分化中のmiR-145発現の定量分析.
- ルシフェラゼレポーターは,OCT4,SOX2,およびKLF4 3' UTRsのmiR-145ターゲティングを検証するためのアッセイである.
- hESCにおけるmiR-145の抑制と機能喪失に関する研究.
- クロマチン免疫降水 (ChIP) は,miR-145プロモーターへのOCT4結合を評価する.
主要な成果:
- miR-145の発現は,自己再生するhESCでは低く,微分化時に著しく増加する.
- miR-145は,OCT4,SOX2,KLF4.4の発現を直接標的にし,抑制する.
- 高濃度のmiR-145はhESCの自己更新を阻害し,多能性遺伝子を低調化し,分化を促進する.
- miR-145の機能の喪失は,分化に障害を与え,OCT4,SOX2,KLF4のレベルを高めます.
- OCT4は,hESCにおけるmiR-145プロモーターに直接結合し,それを抑制する.
結論:
- miR-145と多能性因子OCT4,SOX2,KLF4の間には二重負のフィードバックループが存在する.
- miR-145は,コア再プログラム因子をターゲットにすることで,hESCの差別化を調節する上で重要な役割を果たしています.
- この規制ネットワークは,幹細胞の運命と発達を制御するために不可欠です.
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