核インポートの2段階である核封筒への標的と核孔を通過する転位には,異なる細胞分裂因子が必要です

M S Moore¹, G Blobel

¹Laboratory of Cell Biology, Howard Hughes Medical Institute, Rockefeller University, New York, New York 10021.

Cell

|June 12, 1992

まとめ

研究者らは,哺乳類の細胞に核を輸入するために不可欠な2つの重要なXenopus卵細胞細胞分子を特定しました. 断片Aは核包膜の結合を促進し,断片Bは核孔を通して転位を促す.

科学分野:

細胞生物学細胞生物学
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

背景:

核インポートは,遺伝子調節と細胞機能に不可欠な基本的な細胞プロセスです.
核の輸入を制御する分子機構を理解することは,細胞のコミュニケーションと病気のメカニズムを解読するために不可欠です.

研究の目的:

哺乳類の細胞における核輸入を媒介するXenopusの卵細胞から細胞分解因子を分離し,特徴づけること.
核インポートの2つの重要な段階である核包膜結合と毛孔転移における異なる細胞分子の役割の区別を図る.

主な方法:

Xenopusの卵細胞から2つの異なる細胞分裂分数 (分数Aと分数B) を分離した.
ディジトニンに浸透した哺乳類の細胞を用いて核輸入を測定する.
結合と転位活動を評価するために,核局所化配列ベアリングコンジュガットを使用します.
核輸入経路の各ステップのATP依存性を調査する.

主要な成果:

断片Aは,輸入に適したコンジュガートのATP無関係な結合を核封筒に独立して媒介することが判明しました.
フラクションBは,フラクションAと結合されたり,後に追加されたりすると,結合体のATP依存の転位を核に促進した.
ミュータントの結合体は,輸入に適した結合体とは異なり,フラクションAと相互作用せず,特異性を強調した.

結論:

クセノプス・オオサイトから得られた2つの異なる細胞分解因子は,核インポート中の核包膜結合と核孔転位の両方にとって必要で十分である.
断片Aは核封筒の初期認識とドッキングを担当し,断片Bは核孔複合体を通るエネルギー依存の経路を駆動する.

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