酵母核孔複合体の総合的な構造と機能的適応

Christopher W Akey¹, Digvijay Singh², Christna Ouch³

¹Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, Boston, MA 02118, USA.

Cell

|January 4, 2022

まとめ

酵母核孔複合体 (NPC) の構造を決定し NPC層を繋ぐ柔軟なコネクターを明らかにしましたこの発見は,細胞分裂中のNPCの組み立て,輸送,および潜在的な規制に関する洞察を提供します.

科学分野:

細胞生物学
構造生物学
生物化学

背景:

核孔複合体 (NPC) は,核と細胞質の間の輸送を調節する重要な分子機構である.
NPC構造を理解することは,核細胞質輸送機構の解読に不可欠です.

研究の目的:

内輪を中心に分離された酵母NPCの高解像度構造を解明する.
NPCの組み立てと機能における柔軟なコネクタの役割を調査する.
現地でのNPC構造をモデル化し,輸送規制に関連する特徴を特定する.

主な方法:

低ナノメートルの解像度での冷凍電子顕微鏡 (cryo-EM)
インサイト構造分析のための冷凍電子トモグラフィー (冷凍ET).
ヌクレオポリン相互作用と輸送因子モチーフの分析

主要な成果:

構造と機能の層を繋ぐ柔軟なコネクタを詳細に解明した.
核ポリンと輸送因子の間の保存された相互作用モチーフを特定し,組み立てと輸送の間のリンクを示唆した.
機能的な特異性を持つ3つの主要なNPCの証拠を提供した.
核バスケット,中央トランスポーター,そして膨張を制限するPom152リングの役割を明らかにするインシットNPCのモデルを開発した.

結論:

NPCの構造的可塑性は,効率的な核細胞質輸送に不可欠である可能性があります.
柔軟なコネクタは,フォスフォリレーションと分解によって制御される重要な構造要素です.
同様の相互作用のモチーフは,NPCの組み立てと輸送プロセスの間の進化的および機械的なリンクを示唆しています.

キーワード:

NPCの進化について核孔複合体クリオ電子顕微鏡冷凍電子トモグラフィー内輪の膨張原子力バスケット核サイトプラズマ輸送核ポリン構造的アイソフォーム

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