循環型AMP/GMP依存型のCa2+チャネルの調節により,神経成長コーンの回転の極性が設定されます
Makoto Nishiyama1, Akemi Hoshino, Lily Tsai
1Department of Biochemistry, New York University School of Medicine, New York, New York 10016-6402, USA.
Nature
|June 27, 2003
まとめ
循環型AMP (cAMP) と循環型GMP (cGMP) の比率は,軸索の誘導方向を決定する. 高いcAMP/cGMP比は引き寄せを促進し,低い比は排斥を促し,神経発達に影響を及ぼします.
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:
- 細胞内第2伝達物質であるサイクルヌクレオチドやカルシウムイオン (Ca2+) は,軸索誘導を調節する.
- 双方向性軸索誘導の極性決定におけるこれらのメッセンジャーの正確な相互作用機構は不明である.
研究 の 目的:
- 循環性アデノシンモノフォスファート (cAMP) と循環性グアノシンモノフォスファート (cGMP) のシグナル伝達が,ネットリン-1誘発性軸索の極性を制御するためにどのように相互作用するかを調査する.
- 神経細胞の成長コン内のカルシウムチャネル活性を調節する2番目のメッセンジャーの役割を明らかにする.
主な方法:
- Xenopusの脊髄ニューロン成長コンのCa2+電流の全細胞パッチクランプ記録.
- L型Ca2+チャネル (LCC) 機能に対するサイクルヌクレオチド活性とその影響の分析.
- DCC-UNC5受容体複合体によるネトリン-1媒介反発におけるcGMPシグナル伝達の役割を調査する.
主要な成果:
- cAMPとcGMP活動の比率は,ネットリン-1誘発の軸索誘導の極性を決定し,高い比率は引き寄せを好み,低い比率は排斥を好む.
- サイクルヌクレオチドシグナル伝達は,成長コンのL型Ca2+チャネル活動を直接調節する.
- cGMPシグナリングは,ネトリン-1誘発のLCC活動を抑制し,DCC-UNC5-媒介の成長排斥に不可欠です.
結論:
- cAMPとcGMPのシグナル伝達経路と,成長コンのCa2+チャネル活動との直接的なリンクが確立されています.
- これらの発見は,双方向性軸索誘導における信号伝導のための重要な膜関連メカニズムを明らかにしています.
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