DNA損傷反応画面は,ATRシグナル伝達に必要な9-1-1とTopBP1の相互作用タンパク質であるRHINOを識別します
Cecilia Cotta-Ramusino1, E Robert McDonald, Kristen Hurov
1Department of Genetics, Harvard University Medical School, Howard Hughes Medical Institute, Division of Genetics, Brigham and Women's Hospital, Boston, MA 02115, USA.
Science (New York, N.Y.)
|June 11, 2011
まとめ
研究者らは,DNA損傷反応 (DDR) に不可欠なタンパク質であるRHINOを特定しました. RHINOは他のタンパク質と連携して,DNA修復と細胞サイクル停止に不可欠なATRシグナリングを活性化します.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
背景:
- DNA損傷反応 (DDR) は,DNA損傷を検知し修復する細胞経路の複雑なネットワークです.
- 細胞サイクル停止は,DDRの重要な結果であり,損傷した細胞が複製するのを防ぐ.
研究 の 目的:
- DDR経路に関与する新しいタンパク質を特定する.
- ATRシグナル伝達と細胞サイクル停止における非特徴化されたタンパク質の役割を明らかにする.
主な方法:
- DNA損傷による細胞サイクル停止を誘発した細胞欠乏のスクリーニング.
- 分子生物学の技術を用いて,DNA損傷の部位におけるタンパク質の相互作用を調査する.
主要な成果:
- スクリーンでは,損傷誘発細胞サイクル停止が欠けている細胞を特定し,ATRシグナル伝達におけるファンコーニ貧血と同類復合タンパク質の役割を明らかにした.
- 3つの候補DDRタンパク質,INTS7,CLOCK,RHINOがDNA損傷部位に採用されました.
- RHINOは,Rad9-Rad1-Hus1 (9-1-1) 複合体とTopBP1.1に独立して結合することが判明しました.
- 9-1-1複合体によるDNA損傷部位へのRHINOの徴募は,Chk1の活性化を促進する.
結論:
- RHINOは,9-1-1複合体とTopBP1.1を橋渡しすることで,ATRシグナル伝達に重要な役割を果たしています.
- RHINO,9-1-1複合体,およびTopBP1は,DDRのキーキナーゼであるATRを完全に活性化するために一緒に機能します.
- これらの発見はATR活性化のための新しいメカニズムを明らかにし,DNA修復経路における潜在的な治療標的としてRHINOを強調しています.
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