特殊な肝細胞のような細胞は,ドロソフィラの脂質代謝を調節する
Eugenio Gutierrez1, David Wiggins, Barbara Fielding
1Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK.
Nature
|December 1, 2006
まとめ
ドロソフィラでは,オエノサイトは飢餓中に脂質を処理し,脂肪体の下流に作用します. これは,断食と成長の間にエネルギーにとって不可欠な双方向性脂肪代謝を明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- メタボリック・レギュレーション
- 昆虫生理学 昆虫生理学とは
背景:
- 脂質代謝は,特に飢餓中に,エネルギーにとって不可欠です.
- ドロソフィラ幼虫では,断食中の脂肪体からの脂質の動員が完全に理解されていません.
- 断食昆虫における脂質処理の正確な役割と位置は不明である.
研究 の 目的:
- ドロソフィラの飢餓期における脂質滴の蓄積に責任を負う主要な細胞タイプを特定する.
- 断食中の脂質処理における体脂肪と他の組織との機能的関係を明らかにする.
- 栄養状態と断食状態の両方で脂質代謝を調節するオエノサイトの役割を調査する.
主な方法:
- 重要な代謝遺伝子 (Slimfast,Lsd2,Brummer lipase) を標的とした組織特有の遺伝子操作を使用した.
- 飢餓状態で特定の細胞タイプに脂質滴の蓄積が観察される.
- 脂肪の体脂質貯蔵にオエノサイト機能の影響を分析した.
主要な成果:
- 飢餓中に脂質滴を蓄積する主要な細胞タイプとしてオエノサイトを特定した.
- 脂質処理において脂肪体の下流にオエノサイトが機能することを示した.
- 肥満細胞は,断食中に脂肪の体脂質貯蔵物を枯渇させるのに不可欠であることを示し,双方向結合を示しています.
- 発見されたオエノサイトは,トリアシルグリセロールの調節に関与するCyp4g1を含む多数の脂質代謝タンパク質を発現します.
結論:
- オエノサイトは,脂質代謝と,断食中のドロソフィラ幼虫のエネルギーホメオスタシスにおいて重要な役割を果たします.
- 脂肪体とオエノサイトとの脂質代謝結合は双方向的で,飢餓中の生存に不可欠です.
- オエノサイトは,昆虫内の脂質処理において,哺乳類の肝臓に類似した機能を果たします.
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