核孔複合体を通したプレ-60S粒子の核輸出

Zongqiang Li^1,2, Shuaijiabin Chen^1,2, Liang Zhao^1,2

¹School of Life Sciences, Southern University of Science and Technology, Shenzhen, China.

Nature

|May 31, 2023

まとめ

研究者らは酵母核孔複合体 (NPC) 構造を視覚化し,輸出因子がNPCチャネルを通じて大きなリボソームサブユニット (pre-60S粒子) の輸送をどのように促進するか明らかにしました.

科学分野:

細胞生物学
構造生物学
分子生物学

背景:

核孔複合体 (NPC) は,核と細胞質の間の分子の輸送を調節する.
リボソームサブユニット前駆体 (pre-60Sとpre-40S粒子) は,NPC転移のために輸出因子を必要とする大きな貨物です.

研究の目的:

イーストのNPC内のネイティブのプレ-60S粒子の構造を決定する.
NPCを通じて60S前粒子の輸出のメカニズムを解明する.

主な方法:

クリオ電子顕微鏡 (cryo-EM) を使用して,酵母 NPC のネイティブのプレ-60S 粒子を視覚化しました.
NPC内のプレ-60S粒子の分布を研究するために,in silico分析が行われました.

主要な成果:

凍結-EM構造は,既知の組立因子と,プレ-60S粒子に結合した複数の輸出因子を明らかにした.
これらの要因は,核ポリン内のフェニララニングリシン (FG) リピートと相互作用し,NPC結合のアンカーサイトを形成し,通過を促進します.
シリコ分析では,NPCは内輪領域に濃縮された最大4つのプレ-60S粒子を収容することが示された.

結論:

輸出要因は,NPCを通過するプレ-60S粒子を媒介する上で重要な役割を果たします.
NPCのFG-リピートネットワークとの因子相互作用の重要性を強調する,60S以前の粒子の輸出のための転位モデルが提案されています.

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