Ipomoeassin FはSec61αに結合し,タンパク質の転位を阻害する
Guanghui Zong1, Zhijian Hu, Sarah O'Keefe2
1Department of Chemistry and Biochemistry , University of Maryland , College Park , Maryland 20742 , United States.
Journal of the American Chemical Society
|May 7, 2019
まとめ
植物由来の細胞毒素であるイポモエアシンFは,Sec61α (タンパク質輸送タンパク質Sec61サブユニットアルファ同型1) に直接結合し,タンパク質の転位と分泌を抑制する. この発見は,Sec61αを標的としたがん薬の発見に新しい道を開きます.
科学分野:
- 生物化学
- 分子生物学
- 薬理学について
背景:
- Ipomoeassin Fは未知の生物学的性質を持つ強力な天然細胞毒素である.
- 以前の研究で,イポメアシンFの全合成と薬学的性質が確認された.
研究 の 目的:
- 生体細胞におけるイポメアシンFの直接的な分子標的を特定する.
- イポメアシンFが標的に結合する機能的影響を調査する.
- 治療薬としてイポメアシンFを研究する
主な方法:
- バイオチニル化イポメアシンFアナログを用いた化学プロテオミクス
- アフィニティ・プルダウン・アッセイと ウエスタン・ブロッティング
- インビトロタンパク質転位試験
- 生体内のタンパク質分泌の測定
- Sec61αのサイト指向型変異.
主要な成果:
- Sec61トランスロコンの孔を形成するサブユニットであるSec61α (タンパク質輸送タンパク質Sec61サブユニットアルファ同型1) は,イポメアシンFの直接結合パートナーとして特定されました.
- イポメアシンFとSec61αの相互作用は特異的で強く,逆転可能である.
- イポメアシンFの結合は,活体細胞におけるタンパク質転位とタンパク質分泌を選択的に阻害する.
- Sec61αの特定の変異は,イポメアシンFに耐性を与え,それが主要な分子標的であることを確認します.
結論:
- Ipomoeassin Fは,Sec61αを標的とする最初の植物由来炭水化物ベースの分子です.
- この天然製品は,Sec61α機能を研究するための新しい化学的探査機を提供します.
- Ipomoeassin Fは,がんやその他のタンパク質転位欠陥を含む疾患を標的とした薬剤の発見のための潜在的な治療的リードを表しています.
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