端末軸索の分岐は,前シナプス的なミトコンドリア捕獲を通して,LKB1-NUAK1キナーゼ経路によって調節されます

Julien Courchet¹, Tommy L Lewis, Sohyon Lee

¹Dorris Neuroscience Center and Department of Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla, CA 92037-1000, USA.

Cell

|June 25, 2013

まとめ

LKB1-NUAK1経路は,哺乳類のニューロン軸索の分岐に極めて重要です. この経路は,前シナプス部位でのミトコンドリアの不動化を制御することによって,分岐を調節する.

科学分野:

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

背景:

アクソン樹木化は神経回路形成に不可欠ですが,その分子機構は不明のままです.
ニューロンがどのように複雑な接続を形成するのかを理解することは,神経科学の研究にとって不可欠です.

研究の目的:

哺乳類の皮質軸索の分岐を調節する分子経路を特定する.
アクソン発育におけるキナーゼLKB1とNUAK1の役割を明らかにする.
ミトコンドリア輸送と軸索の分岐の間の関係を調査するために.

主な方法:

条件付きの遺伝子削除とノックダウン技術 in vivo.
キナーゼ機能を評価するための過剰発現の研究.
ミトコンドリア輸送を研究するためにシンタフィリンの操作.
顕微鏡検査と画像検査で,軸索の形態学とミトコンドリアの位置を分析する.

主要な成果:

LKB1-NUAK1キナーゼ経路は,体内で皮質軸索の分岐に不可欠である.
LKB1の削除またはNUAK1のノックダウンにより,軸索の分岐が著しく減少します.
LKB1またはNUAK1の過剰発現は,軸索の分岐を高めます.
この経路は,軸索内のミトコンドリアの不動化を促進することによって,軸索の分岐を調節する.
LKB1とNUAK1はミトコンドリアを,特に新生前シナプス部位で固定する.

結論:

LKB1-NUAK1経路は,哺乳類のニューロンにおける軸索の分岐の重要な調節体である.
LKB1-NUAK1によって媒介されるミトコンドリアの不動化は,軸索の樹木化のための重要なメカニズムです.
この研究は,前シナプス的なミトコンドリア捕捉とニューラル接続の形成の間の新しいリンクを明らかにしています.

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