三核钌胺钌红(RuR)抑制多种离子通道,包括K2P钾通道,TRP,钙运输者,CALHM,ryanodine受体,还有Piezos.尽管有这个非凡的阵列,关于RuR如何参与目标的信息有限。这里,使用对RuR敏感的K2P的X射线晶体学和电生理学研究,K2P2.1(TREK-1)I110D,我们表明RuR通过在通道孔上方的K2PCAP结构域拱道下结合包含“Keystone抑制剂位点”的酸性残基对而起作用。我们进一步确定Ru360,一种未知影响K2Ps的双核钌胺,使用相同的机制抑制RuR敏感的K2Ps。结构知识为创建具有纳摩尔灵敏度的K2PRuR“超级响应器”提供了可推广的设计策略。一起,数据定义了作用于新型K2P抑制剂结合位点的“大坝中的手指”抑制机制。这些发现强调了K2P药理学的多位点性质,并为K2P抑制剂的开发提供了新的框架。
The trinuclear ruthenium amine ruthenium red (RuR) inhibits diverse ion channels, including K2P potassium channels, TRPs, the calcium uniporter, CALHMs, ryanodine receptors, and Piezos. Despite this extraordinary array, there is limited information for how RuR engages targets. Here, using X-ray crystallographic and electrophysiological studies of an RuR-sensitive K2P, K2P2.1 (TREK-1) I110D, we show that RuR acts by binding an acidic residue pair comprising the \"Keystone inhibitor site\" under the K2P CAP domain archway above the channel pore. We further establish that Ru360, a dinuclear ruthenium amine not known to affect K2Ps, inhibits RuR-sensitive K2Ps using the same mechanism. Structural knowledge enabled a generalizable design strategy for creating K2P RuR \"super-responders\" having nanomolar sensitivity. Together, the data define a \"finger in the dam\" inhibition mechanism acting at a novel K2P inhibitor binding site. These findings highlight the polysite nature of K2P pharmacology and provide a new framework for K2P inhibitor development.