RASは,let-7マイクロRNAファミリーによって調節されます
Steven M Johnson1, Helge Grosshans, Jaclyn Shingara
1Department of Molecular, Cellular and Developmental Biology, Yale University, P.O. Box 208103, New Haven, CT 06520, USA.
Cell
|March 16, 2005
まとめ
let-7マイクロRNAファミリーは,虫とヒトの両方のRAS遺伝子発現を調節する. ヒトの肺腫瘍におけるレット-7の低いレベルは,高いRASタンパク質と相関し,がんにおける役割を示唆している.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学について
背景:
- マイクロRNA (miRNA) は,真核生物における遺伝子発現の重要な調節因子である.
- let-7 miRNAファミリーは,細胞の分化を含む発達過程において重要な役割を果たします.
- RAS遺伝子は,ヒトの癌で頻繁に変異し,細胞の成長と増殖に関与しています.
研究 の 目的:
- let-7 miRNAファミリーとRAS経路の間の規制関係を調査する.
- let-7がモデル生物とヒトの両方のRAS遺伝子を直接標的にするかどうかを判断する.
- 肺がんの文脈におけるlet-7とRASの潜在的な役割を調査する.
主な方法:
- レポーター遺伝子アッセイは,let-60/RAS.のlet-7媒介調節を評価するためのものです.
- C. elegansの発達中のlet-7ファミリーメンバーの表現の分析.
- 人間の肺腫瘍組織におけるlet-7およびRAS発現レベルの検査.
主要な成果:
- let-7ファミリーは,C. elegans.におけるlet-60/RASをネガティブに調節することが示されました.
- let-60/RASの3'UTRで複数のlet-7補完部位 (LCS) が特定され,let-7依存抑制を媒介している.
- 人間のRAS遺伝子3'UTRには,LCSも含まれており,レット-7調節が保存されていることを示している.
- Let-7発現の減少とRASタンパク質の濃度の上昇は,ヒトの肺腫瘍で観察されました.
結論:
- let-7 miRNAファミリーは,保存されたメカニズムを通じてRAS遺伝子発現を直接抑制する.
- let-7-RAS軸の調節不良は,let-7の減少とRASの増加とともに,ヒトの肺腫瘍発生に関与しています.
- この研究は,レット7機能とがん発症の間の分子関連性を示しています.
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