分子混雑は,基質認識の前に内生タンパク質を持つ非特異的な複合体へと活性Pin1を駆動する
Laura M Luh1, Robert Hänsel, Frank Löhr
1Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University , Frankfurt, 60438, Germany.
Journal of the American Chemical Society
|August 24, 2013
まとめ
細胞の混雑は,弱い魅力的な相互作用を通してタンパク質の行動に影響を与える. Ficoll 70のような分子混雑剤は,これらの細胞内相互作用を正確に模倣することはできません.
科学分野:
- バイオケミストリー バイオケミストリー
- 細胞生物学 細胞生物学
- バイオフィジックス 生物物理学
背景:
- マクロ分子混雑は,細胞環境に大きな影響を及ぼし,タンパク質のダイナミクス,構造,および活動に影響を与えます.
- 混雑がタンパク質の機能を in vivo で変化させる正確なメカニズムについては,議論が続いている.
- これらの効果を理解することは,細胞のプロセスを理解する上で極めて重要です.
研究 の 目的:
- Xenopus laevis卵細胞内のペプチジルプロリルイソメラーゼPin1における分子混雑の役割を調査する.
- 混雑した細胞環境におけるタンパク質の行動に影響を与える特異的および非特異的相互作用を区別する.
- 本来の細胞内状態を複製する合成混雑剤の適性を評価する.
主な方法:
- 細胞内核磁気共振 (NMR) スペクトロスコピーは,Pin1.1を研究するために使用されました.
- 実験はネイティブのXenopus laevisの卵細胞と混雑した卵細胞抽出物で行われました.
- Pin1の相互作用に対するリン酸化の影響を分析した.
主要な成果:
- アクティブPin1は,基板結合の前に細胞内タンパク質と弱い魅力的な相互作用をします.
- Pin1の基板認識部位は,特定と非特定の両方の魅力的な相互作用を媒介する.
- Pin1のWWドメインのリン酸化は,基板認識と内生タンパク質の相互作用を無効にする.
- Ficoll 70のような合成混雑剤は,in vivoで見られる本質的な弱引力相互作用を複製することができない.
結論:
- この研究は,混雑した環境で複合体を形成する中性球状タンパク質に関するマコニーの仮説を裏付けている.
- 非特異的な弱引力相互作用は,細胞内環境の重要な構成要素である.
- 合成の混雑剤は,複雑なネイティブの細胞環境を正確にシミュレートするには不十分です.
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