ハームは,哺乳類のカルシウム依存性Slo1 BKチャネルに結合し,それを阻害することができます
Xiang Dong Tang1, Rong Xu, Mark F Reynolds
1Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Nature
|October 3, 2003
まとめ
タンパク質に欠かせないヘームは,カルシウム依存性Slo1 BKチャネルを直接調節する. この結合は,カリウム電流を阻害し,急性シグナル伝達分子としてのヘムの新たな役割を明らかにします.
科学分野:
- バイオケミストリー バイオケミストリー
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
背景:
- ヘムはヘムタンパク質の重要なコファクターであり,酸化還元反応に不可欠です.
- ヘミは,生殖過程で酵素的にアポヘムタンパク質に組み込まれます.
- 大導電性カルシウム依存性Slo1 BKチャネルは,保存されたヘム結合モチーフを特徴としています.
研究 の 目的:
- ヘムとSlo1 BKチャネルの間の直接的な相互作用を調査する.
- BKチャネル活動に対するヘム結合の機能的影響を明らかにする.
主な方法:
- クローン化された人間のSLO1とネズミの脳の野生型のBKチャネルの電気生理学的記録.
- ヘム-チャネル相互作用の構造的証拠分析.
主要な成果:
- ヘムは,酸化状態と還元状態の両方でヒトのSlo1 (hSlo1) チャンネルタンパク質に直接結合します.
- ヘム結合は,膜を越えたK+電流を深刻に阻害する.
- 阻害は,チャネル開封の頻度を下げることによって発生します.
結論:
- ヘムは,Slo1 BKチャネルを直接調節する.
- この相互作用は,急性シグナル伝達分子としてのヘムの新しい機能を明らかにします.
- BKチャネルは,ヘム媒介の調節のための直接的な標的である.
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