アミノ酸とデオキシヌクレオシド,およびそれらのオリゴマー間のフォーマルデヒド誘発のクロスリンクの構造的特徴
1Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
Journal of the American Chemical Society
|February 25, 2010
まとめ
フォーマルアルデヒドへの曝露は,DNA-タンパク質クロスリンク (DPC) を引き起こします. この研究では,アミノ酸とDNA塩基間のフォーマルデヒド誘発のクロスリンクを特徴付け,メチレンブリッジとトリアジノ環を明らかにし,バイオマーカーの識別を支援しました.
科学分野:
- 化学生物学 化学生物学とは
- 遺伝子毒理学 遺伝子毒理学
- 分子毒理学 分子毒理学
背景:
- フォーマルアルデヒドは,DNA-タンパク質クロスリンク (DPC) を引き起こす遺伝子毒性物質です.
- フォーマルデヒド誘発型DPCの特異的な構造は,ほとんど解明されていないままです.
- 8種類のアミノ酸は,ホルマルデヒドと安定したアダクトを形成することが知られている.
研究 の 目的:
- アミノ酸とDNA塩基間のホルムアルデヒド誘発のクロスリンクの構造を特徴付けるために.
- どのアミノ酸とDNA塩基がホルムアルデヒドと安定したクロスリンクを形成しているのかを特定する.
- 構造的な洞察を提供することで,DPCの形成をin vivoで理解し,ホルムアルデヒド曝露のためのバイオマーカーを開発します.
主な方法:
- フォーマルデヒドが特定のアミノ酸 (Lys,Cys,His,Trp) とDNA塩基 (dG,dA,dC) と反応する.
- 核磁共振 (NMR) と質量スペクトロメトリを用いた構造的特徴付け.
- シングルヌクレオシド,トリヌクレオチド,および8メルペプチドで形成されたクロスリンクの分析.
主要な成果:
- リンジンとdGは,交互にリンクされた製品で最も高い収量を示し,次にCysとdGが続いた.
- 交差リンクは主に,アミノ酸と核酸の間の,ホルムアルデヒド由来メチレンブリッジを含む.
- リンジンは,1,N(2) と融合したトリアジノ環を含むdGで追加の製品を形成し,これらは不安定であった.
- 構造は,NMR,質量スペクトロメトリ,および断片化パターンを用いて確認されました.
結論:
- フォーマルデヒド誘発のDNAとタンパク質のクロスリンクの詳細な構造が解明されました.
- 特定された構造にはメチレンブリッジとトリアジン環が含まれています.
- これらの発見は,DPCs in vivoの研究と,フォーマルデヒド暴露のためのバイオマーカーの開発を容易にするでしょう.
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