細胞内カルシウムイオンの局所的な増加によって誘発される神経成長コンの回転
1Department of Neuroscience and Cell Biology, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway 08854, USA. zhengiq@umdnj.edu
Nature
|January 19, 2000
まとめ
局所化されたカルシウム信号は,軸索の発達を誘導する. 細胞内カルシウム濃度 ([Ca2+]i) の直接的,側面特異的な増加は成長を惹きつけ,休息中の[Ca2+]iの減少は排斥を引き起こし,カルシウムを明らかにする.
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
- 発達生物学 発達生物学とは
背景:
- 軸の誘導は,神経回路の形成に不可欠です.
- 成長の回転は細胞外信号に依存するが,細胞内メカニズムは不明である.
- カルシウムイオン (Ca2+) は,成長コンのダイナミクスにおける第2のメッセンジャーとして関与しています.
研究 の 目的:
- 成長コンの回転における局所化された細胞内カルシウム濃度 ([Ca2+]i) の役割を調査する.
- 焦点カルシウムの上昇が細胞内指向的なシグナルとして機能するかどうかを判断する.
- カルシウム媒介の回転反応に対する変化した休憩 [Ca2+]i の影響を調べる.
主な方法:
- 空間的に制限された[Ca2+]i上昇を達成するために,ケージ化されたカルシウムを焦点レーザー誘発光分解 (FLIP) します.
- 休息状態[Ca2+]iを変化させるため,細胞外カルシウムレベルを操作する.
- 成長コーンの回転動作の観察と定量化.
主要な成果:
- 成長の片側に[Ca2+]iの直接的,焦点的な上昇は,その側への引き寄せを誘導した.
- 静止状態の[Ca2+]iが減少すると,同じ焦点の[Ca2+]iの上昇が排斥を引き起こす.
- 局所化されたカルシウム信号は,魅力的および排斥的な回転反応の両方を開始するのに十分です.
結論:
- 局所化された細胞内カルシウム信号は,軸索拡張のための直接的な方向性シグナルを提供します.
- 成長の回転反応 (引き寄せ/反発) は,局所カルシウム増加と全局カルシウムレベルの両方に依存します.
- このメカニズムは,成長コーンが開発中にナビゲーションのための信号を統合することを可能にします.
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