衝突したリボソームでのZAK活性化

Vienna L Huso^1,2, Shuangshuang Niu³, Marco A Catipovic^1,2

¹Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

Nature

|November 19, 2025

まとめ

リボソームの衝突によりストレス反応の鍵となる ZAKキナーゼが活性化しますこの研究は,ZAK

科学分野:

分子生物学
細胞のストレス反応
タンパク質キナーゼシグナル

背景:

リボソームの衝突は,ZAKキナーゼと下流MAPKを含むリボトキシカルストレス反応を誘発する.
ZAK- リボソームの相互作用と活性化の正確なメカニズムは十分に理解されていません.

研究の目的:

リボソーム衝突によるZAKキナーゼ活性化の構造的およびメカニズム的基礎を解明する.
ZAK,リボソーム,および調節タンパク質の間の重要な相互作用を特定する.

主な方法:

生物化学
電子冷凍顕微鏡 (EM冷凍)
ZAK SAMドメインの変数解析

主要な成果:

徴募と活性化には明確なZAK-リボソーム相互作用が必要である.
ZAKの活性化は,RACK1を含むリボソーム衝突部位でのSAMドメイン二分化によって起こります.
SERBP1は,ZAKの活性化を否定的に調節し,その構成的活動を阻害する.
ZAK SAMドメインの変異は,リボソームのオンとオフのキナーゼ活性に影響を与えます.

結論:

衝突したリボソームのZAKキナーゼ活性に対するメカニズム的な設計図を提供します.
細胞のストレス反応における ZAK-リボソーム相互作用の役割を強調する.
ZAK活性化の主要な負のレギュラーとしてSERBP1を特定します.

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