Fe-Sクラスター生物発生に関与する特殊なHsp70/Hsp40複合体内の核酸依存相互作用
Jin Hae Kim1, T Reid Alderson, Ronnie O Frederick
1Mitochondrial Protein Partnership, Center for Eukaryotic Structural Genomics, and ‡Department of Biochemistry, University of Wisconsin , Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|August 2, 2014
まとめ
HscBのHPDモチーフは,ATP結合のHscAと直接相互作用する一方,HscBの第2結合部位は,ATP結合のHscAと直接相互作用する.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
背景:
- Hsp70型チャペロンとHsp40型コチャペロンは,タンパク質のホメオスタシスに不可欠です.
- これらのチャペロン間の正確な相互作用のメカニズムは,まだ完全に理解されていません.
- エシェリキア大腸菌 HscA と HscB は,鉄硫黄のクラスター移転に関与する特殊なチャペロンである.
研究 の 目的:
- HscAとHscBのATP/ADP依存の相互作用メカニズムを解明する.
- HscA-HscB複合体の形成に関与する特定のドメインと残基を特定する.
- HscBの機能におけるHPDモチーフの役割を理解する.
主な方法:
- 溶液NMRスペクトロスコピーは,HscA-HscBの相互作用を研究するために使用されました.
- サイト指向型変異は,HSCBのHPDモチーフを変更するために使用されました.
- 変異の機能的影響を評価するために,ATP水解アッセイが行われました.
主要な成果:
- HPDモチーフを含むHscBのJドメインのNMR信号は,ATP結合のHscAが加わると拡大するが,ADP結合のHscAは加わらない.
- 変異したHPDモチーフ (HscB(H32A,P33A,D34A)) のHscB変異種は,有意なNMR信号変化を示せず,HscAのATP水解刺激を廃止しました.
- HscBのC末端領域の153-171の残留物も,HscAとの相互作用でNMRの乱れを示し,第2の結合部位を示した.
結論:
- HscBのHPDモチーフは,ATP結合のHscAと直接相互作用する.
- HscAのための二次的,より少ないヌクレオチド依存の結合部位は,HscBのC端部に位置しています.
- これらの発見は,Hsp70-Hsp40のチャペロン協力の構造的基盤に関する重要な洞察を提供します.
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