カルレチクリンは,インテグリン媒介カルシウムシグナル伝達と細胞粘着に不可欠です
M G Coppolino1, M J Woodside, N Demaurex
1Division of Cancer Research, Sunnybrook Health Science Centre, Toronto, Ontario, Canada.
Nature
|April 24, 1997
まとめ
カルレチキュリンは,インテグリン媒介の細胞結合と信号伝達に不可欠です. カルレチキュリンの欠乏は,細胞の結合とインテグリン機能に不可欠なカルシウム流入を損なう.
科学分野:
- 細胞生物学 細胞生物学
- 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:
- インテグリンは細胞結合と信号伝導を媒介する.
- カルレチキュリンはインテグリンアルファサブユニットと相互作用し,細胞粘着に影響を与えます.
- インテグリン機能におけるカルレチキュリンの役割を理解することは,極めて重要です.
研究 の 目的:
- インテグリン媒介細胞結合とシグナル伝達におけるカルレチキュリンの役割を調査する.
- インテグリンエンゲージメントによって開始されたカルシウムトランジエントに対するカルレチクリンの影響を決定するために.
主な方法:
- カレチクリン欠乏性の胚性幹細胞 (ES細胞) と線維芽細胞の発達.
- 野生型およびカルレチクリン欠乏細胞におけるインテグリン媒介結合の評価.
- インテグリン結合時に生じる細胞内カルシウム濃度の変化の分析.
主要な成果:
- カルレチクリン欠乏細胞は,インテグリン媒介による粘着がひどく損なわれている.
- インテグリン発現は,カルレチキュリンがない場合でも変化しません.
- カルレチクリン欠乏症は,インテグリン結合によって典型的に誘発されるカルシウムトランジエントを廃止し,内膜カルシウム貯蔵には影響しません.
結論:
- カルレチキュリンは,インテグリン粘着機能の重要な調節剤です.
- カルレチキュリンは,インテグリンが誘発するシグナル伝達経路,特にカルシウム流入において重要な役割を果たします.
- カルレチキュリンは,内カルシウムの貯蔵に有意に関与していません.
関連する概念動画
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01:10Integrins
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01:15Activation of Integrins
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01:17Intracellular Signaling Affects Focal Adhesions
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01:24Adherens Junctions
Strong contact points between adjacent cells anchor them to each other, forming tissues. Such anchoring junctions are of two types – adherens junctions and desmosomes. Adherens junctions are abundant in tissues such as epithelium and endothelium, forming a continuous zone of adhesion called the adhesion belt. In other tissues, such as heart muscle, they appear as clusters, linking the cells to produce coordinated heart muscle contraction.
Adherens Junctions are Dynamic
The endothelial cells...
Adherens Junctions are Dynamic
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01:31Immunoglobulin-like Cell Adhesion Molecules
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Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...