アプタマー活動の光調節:ケージ化されたチミジン核塩基を持つ抗トロビンアプタマー
Alexander Heckel1, Günter Mayer
1Kekulé-Institute for Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany. heckel@uni-bonn.de
Journal of the American Chemical Society
|January 20, 2005
まとめ
合成されたDNAアプタマーには,光性グループがあり,光でスイッチを入れることができます. この光活性化DNAアプタマー技術は,治療用途のアプタマー機能を制御する新しい方法を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 薬用化学 薬用化学について
背景:
- アプタマーは,標的分子の特異性と親和性が高い核酸ベースのリガンドです.
- アプタマー活性を制御することは,治療的応用,特に抗凝固剤において極めて重要です.
- フォトラビルの保護群は,生物分子の光誘発活性化のための方法を提供します.
研究 の 目的:
- ティミジン残基の光耐性保護基を持つ"ケージド"DNAアプタマーを合成する.
- アンチトロンビンアプタマーの機能に対するケージドチミジンの効果を調査する.
- アプタマー活動の光誘発的回復を証明するために.
主な方法:
- 15ヌクレオチド単鎖DNA (ssDNA) 抗トロンビンアプタマーの化学合成.
- フォトラビルな保護基でチミジン核酸の改変.
- 表面プラズマ共鳴 (SPR) のような技術を使用して,トロンビンに対するアプタマー結合親和性の評価.
- アプタメルの血液凝固カスケードの阻害の評価.
- 366nmの光を用いて,改変したアプタメルの光化学的解鎖.
主要な成果:
- フォトラビルチミジン改変による"ケージ" ssDNA 抗トロビンアプタマーの合成.
- 重要な場所にある1つのケージされたチミジンは,アプタマーがトロンビンと結合することを完全に廃止しました.
- 閉じ込められたアプタミーは,血液の凝固カスケードを抑制できませんでした.
- 366nmの光で照射すると,効率的に光耐性保護群が除去されます.
- 開封は,アプタマーのトロンビンに対する親和性と,その抗凝固作用を回復させた.
結論:
- ティミジン残基の写真性"ケージング"は,アプタマー機能に対する効果的な時間的な制御を提供します.
- 光誘発による開封は,抗トロンビンアプタメアの生物学的活動を迅速に回復させます.
- この光活性化アプタマー系は,制御可能な抗凝固療法の開発に有望である.
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