Mironova G D, Skarga Y Y, Grigoriev S M, Negoda A E, Kolomytkin O V, Marinov B S
Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia.
J Bioenerg Biomembr. 1999 Apr;31(2):159-63. doi: 10.1023/a:1005408029549.
Electrical properties and regulation of the mitochondrial ATP-dependent potassium channel were studied. The channel protein was solubilized from the mitochondrial membrane using an ethanol/water mixture. Reconstituted into a bilayer lipid membrane BLM), the protein formed a slightly voltage-dependent channel with a conductance of 10 pS in 100 mM KCl. Often, several channels worked simultaneously (clusters) when many channels were incorporated into the BLM. The elementary channel and the clusters were both highly potassium selective. At concentrations of 1 to 10 microM, ATP favors channel opening, while channels become closed at 1-3 mM ATP. GDP (0.5 mM) reactivated the ATP-closed channels without affecting the untreated channels. The sulfhydryl-reducing agent ditiothreitol increased the open probability at concentrations of 1 to 3 mM, but damaged the selectivity of the channel.
研究了线粒体ATP依赖性钾通道的电学性质及其调节机制。使用乙醇/水混合物从线粒体膜中溶解通道蛋白。将其重构到双层脂质膜（BLM）中，该蛋白形成了一个对电压略有依赖性的通道，在100 mM KCl中电导为10 pS。当许多通道整合到BLM中时，通常会有几个通道同时起作用（簇状）。基本通道和簇状通道都具有高度的钾选择性。在1至10 microM的浓度下，ATP有利于通道开放，而在1至3 mM ATP时通道关闭。GDP（0.5 mM）可使ATP关闭的通道重新激活，而不影响未处理的通道。巯基还原剂二硫苏糖醇在1至3 mM的浓度下增加了开放概率，但损害了通道的选择性。
