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Updated: Jun 11, 2026
10:32
On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids
Published on: March 2, 2012
カルシウムイオンとイノシトール1,4,5-トリスフォスファートのメッセンジャー作用の範囲
N L Allbritton1, T Meyer, L Stryer
1Department of Cell Biology, Stanford University, CA 94305.
Science (New York, N.Y.)
|December 11, 1992
まとめ
イノシトール1,4,5-トリスホスファート (IP3) は,20ミクロン未満の細胞でグローバルメッセンジャーとして作用し,カルシウム (Ca2+) はバッファリングにより制限ドメインで機能する.
科学分野:
- 細胞信号伝達と分子生物学.
- 拡散と分子相互作用の生体物理学.
背景:
- カルシウムイオン (Ca2+) とイノシトール1,4,5-トリフォスファート (IP3) は,細胞内伝達物質として重要な役割を果たしています.
- 拡散ダイナミクスを理解することは,細胞の反応を解読する鍵です.
研究 の 目的:
- Ca2+およびIP3ポイントソースの有効な作用範囲を決定する.
- これらのメッセンジャーの拡散特性を細胞抽出物で比較するために.
主な方法:
- Xenopus laevisの卵細胞細胞抽出物における [3H]IP3とCa2+の拡散係数 (D) の測定.
- 異なる濃度 (90 nMから1 microM) でCa2+拡散の分析.
主要な成果:
- IP3の拡散係数 (D) は283ミクロン2/秒でした.
- Ca2+拡散係数 (D) は,濃度が増加するにつれて13から65ミクロン2/sの範囲であった.
- 計算された有効範囲は,自由Ca2+ (0.1ミクロン),バッファリ化Ca2+ (5ミクロン),IP3 (24ミクロン) です.
結論:
- IP3は,20ミクロン未満の細胞でグローバルメッセンジャーとして作用します.
- Ca2+は,移動性および不移動性コンポーネントによるバッファリングにより,局所化されたメッセンジャーとして作用します.
- バッファリングは,IP3と比較してCa2+の拡散範囲を大幅に制限します.
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