ミトコンドリア内膜AAA+プロテアゼYME1の構造は,基板処理の洞察を与える
Cristina Puchades1,2, Anthony J Rampello3, Mia Shin1,2
1Department of Integrative Structural and Computational Biology, The Scripps Research Institute HZ 175, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
まとめ
ミトコンドリア内部のAAA+プロテアゼであるYME1の原子構造を明らかにしました この構造は,ATPASEが質管理のためのスパイラル階段メカニズムを通して展開されたタンパク質基板をどのように関与させ,転位させるかを示しています.
科学分野:
- 分子生物学
- 構造生物学
- セルラー品質管理
背景:
- AAA+プロテアゼは細胞のプロテオスタシスの維持に不可欠です.
- YME1は,品質管理に関与する重要な内 mitochondrial 膜 AAA+ タンパク質である.
- 基板転移のメカニズムを理解することは,プロテアースの機能を理解するための鍵です.
研究 の 目的:
- 酵母YME1タンパク質の原子構造を決定する.
- AAA+ ATPasesによる基板の関与と転位のメカニズムを解明する.
- AAA+タンパク質の保存された転位機構についての洞察を提供するためです.
主な方法:
- クリオ電子顕微鏡 (cryo-EM) ~3.4アングストームの解像度
- 酵母YME1プロテアゼの原子モデル構造
- ヌクレオチド結合状態と基板相互作用への影響の分析.
主要な成果:
- 基板に結合した酵母YME1の~3. 4アングストロムの冷凍-EM構造が得られた.
- 構造は,展開された基板の周りに螺旋の階段を形成するAAA+ ATPaseを明らかにします.
- 異なるヌクレオチド状態は,チロシン位置付けによる基板の結合と転位をアロステリックに制御する.
結論:
- 連続した環周ATP水解サイクルが基板転移を段階的に推進する.
- ヒンジライクリンカーは,ATPaseのスパイラルとタンパク質塩基間の大規模な動きに対応します.
- 解明された転位メカニズムは,様々なAAA+ ATPasesで保存されている可能性が高い.
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