核毛孔複合体の年齢による劣化は,転移後の細胞における核の完全性の喪失を引き起こします
Maximiliano A D'Angelo1, Marcela Raices, Siler H Panowski
1Salk Institute for Biological Studies, Molecular and Cell Biology Laboratory, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
Cell
|January 27, 2009
まとめ
核孔複合体 (NPC) は,分裂細胞とは異なり,分化細胞では長寿である. NPCの老化はNPCの損傷につながり,核透過性を高め,NPCが老化過程で役割を果たしていることを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 老化に関する研究
- 分子生物学は分子生物学である.
背景:
- 核孔複合体 (NPC) は,核サイトプラズマ輸送に不可欠である.
- NPCは細胞分裂 (ミトーシス) 時に分解して再構成する.
- 非分裂 (転移後) 細胞におけるNPCの運命と安定性は,依然としてほとんど特徴づけられていない.
研究 の 目的:
- 分化され,転移後の細胞におけるNPCの転移と安定性を調査する.
- NPCが年齢に関連した変化を経験するかどうかを判断する.
- 老化中のNPC変化の機能的影響を調査する.
主な方法:
- 微分化された細胞における核ポリン (NPC成分) の安定性を追跡するための技術を使用した.
- 異なる年齢の細胞でNPCの完全性と核浸透性を評価した.
- 古い細胞におけるヌクレオポリンによる酸化ダメージ状態を調査した.
主要な成果:
- 核孔複合体 (NPC) は,微分化した細胞ではターンオーバーを示さない. 基板核ポリンは,細胞の寿命を通して例外的に安定している.
- NPCコンポーネントのサブセット (例えば,Nup153,Nup50) は,継続的に交換されます.
- 老化は,NPCの劣化,核透性の増加,細胞質タンパク質の核への漏出と相関しています.
- ヌクレオポリンに対する酸化的損傷は,老いた細胞で観察される.
結論:
- 核毛孔複合体は,微分化した細胞の非常に安定した構造です.
- NPCは老化に関連した損傷を受け,核の透過性を高めるのに寄与します.
- NPCでの損傷の蓄積は,細胞の老化における重要な出来事です.
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