関連する実験動画
Updated: Jul 9, 2026
10:12
Measuring Spatial and Temporal Ca2+ Signals in Arabidopsis Plants
Published on: September 2, 2014
細胞表面受容体は,ガード細胞における細胞外Ca2+) 感受を媒介する
Shengcheng Han1, Ruhang Tang, Lisa K Anderson
1Department of Biology, Developmental, Cell, and Molecular Biology Group, Duke University, Durham, North Carolina 27708, USA.
Nature
|September 12, 2003
まとめ
植物は,細胞外カルシウム (Ca2+o) を監視するために新しいカルシウム感知受容体 (CAS) を利用します. この受容体は,カルシウムホメオスタシスの調節と植物の発達,特にガード細胞において極めて重要です.
科学分野:
- 植物生理学 植物生理学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- 細胞外カルシウム (Ca2+o) は,植物生理学的および発達的プロセスに不可欠です.
- 植物は,外部の変動にもかかわらず,内部カルシウムホメオスタシスを維持し,洗練された感知機構を暗示します.
- 植物のCa2+o感知受容体の存在と性質は,ほとんど不明のままである.
研究 の 目的:
- 細胞外カルシウム (Ca2+o) を感知する植物受容体を特定する.
- カルシウムシグナル伝達と植物反応におけるこのような受容体の役割を調査する.
- 新たに特定されたCa2+o感知受容体の機能と局所を特徴づける.
主な方法:
- アラビドプシスのcDNAを分離するために哺乳類の細胞における機能的スクリーニングアッセイ.
- 植物細胞内で特定された受容体 (CAS) の局所化研究.
- カルシウムシグナル伝達と植物現象型に及ぼす影響を研究することによって,CAS機能の分析.
主要な成果:
- カルシウム感知受容体 (CAS) をコードするArabidopsisのcDNAクローンが分離されました.
- CASは,低親和度,高容量のCa2+結合を持つ,血局所化されたタンパク質です.
- CASは細胞外カルシウム誘発による細胞内カルシウム ([Ca2+]i) の増加を媒介し,特にガード細胞に作用する.
結論:
- CASは,植物における細胞外カルシウム (Ca2+o) の主要なトランスデューサーとして特定されています.
- CASは,ガード細胞と植物発達のCa2+oシグナル伝達において重要な役割を果たしています.
- CAS機能の障害は,カルシウム欠乏に対する植物の反応を損なう.
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