新しく合成された膜タンパク質を,軸索の成長コンズに優先的に添加する
A M Craig1, R J Wyborski, G Banker
1Department of Neuroscience, University of Virginia School of Medicine, Charlottesville 22908, USA.
Nature
|June 15, 1995
まとめ
新しく合成されたプラズマ膜タンパク質は,好ましくニューロンに追加されます.
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:
- アクソンの成長には,プラズマ膜タンパク質の添加が必要です.
- 成長するアクソン膜にタンパク質が挿入されるメカニズムは完全に理解されていません.
- 潜在的なメカニズムには,成長コンの挿入,均一の挿入,または大量フローで細胞体の挿入が含まれます.
研究 の 目的:
- 軸索の成長中に新しいプラズマ膜タンパク質の添加部位を調査する.
- 優先成長コンの挿入,均一の挿入,またはバルクフローの細胞体の挿入を区別するために.
主な方法:
- 欠陥のあるヘルペスウイルスベクトルを,マウスのヒポカンパニューロン培養で遺伝子発現に利用した.
- 局所化を追跡するために,外因的トランスメブランタンパク質,CD8αを発現した.
- 顕微鏡を用いてタンパク質の分布を時間とともに観察した.
主要な成果:
- 新しく合成されたCD8αタンパク質は,当初,成長の軸索表面にほぼ独占的に現れました.
- 成長コンの好ましい加算は,未成熟のデンドライトでも,成熟したデンドライトでは認められませんでした.
- 数時間かけて,CD8αはニューロンの表面全体に均一な分布を達成し,拡散と内細胞循環を示唆した.
結論:
- プラズマ膜タンパク質は,神経細胞の成長コーンで選択的に追加されます.
- この成長の好ましい挿入は,軸索表面分子の極化分布に寄与する.
- この発見は,成長コンのターゲティングが軸索の発達と膜組成の重要なメカニズムであるモデルを支持する.
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