RNPの輸出は,核エンベロープの芽生えによる

Emily M Hatch¹, Martin W Hetzer

¹Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.

Cell

|May 15, 2012

まとめ

筋肉細胞は,新しいmRNA輸出経路を利用し,核毛孔複合体を回避する. リボ核タンパク質複合体は,神経筋の結合形成のために核膜を通過します.

科学分野:

分子生物学は分子生物学である.
細胞生物学細胞生物学
神経科学は神経科学である.

背景:

核孔複合体 (NPC) は,核から細胞質へのメッセンジャーRNA (mRNA) 輸出の確立された経路である.
mRNAの輸送メカニズムを理解することは,遺伝子発現の調節と細胞機能にとって極めて重要です.

研究の目的:

特殊な細胞タイプにおける代替的なmRNAエクスポートメカニズムを調査する.
核包膜の横断でリボヌクレオプロテイン複合体輸送の経路を特定する.

主な方法:

筋肉細胞におけるmRNA輸送の生細胞イメージング.
神経筋肉の交差点形成中の核封筒のダイナミクスの分析.
輸出されたリボ核タンパク質複合体の生化学的特徴.

主要な成果:

筋肉細胞におけるmRNAエクスポートのための非NPC経路の発見.
リボヌクレオプロテイン複合体が核膜と融合し,核膜を通過する証拠.
この経路を利用して,神経筋結節の組み立てに関与する特定の複合体の特定.

結論:

核輸出は,核孔複合体によってのみ媒介されるものではない.
新しい膜密輸メカニズムは,特定の細胞機能のためのmRNAの輸出を容易にする.
この経路は,神経筋肉の結合の発達と維持に不可欠です.

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