PDF(Pubmed)
Abstract：
Ion channels establish the voltage gradient across cellular membranes by providing aqueous pathways for ions to selectively diffuse down their concentration gradients. The selectivity of any given channel for its favored ions has conventionally been viewed as a stable property, and in many cation channels, it is determined by an ion-selectivity filter within the external end of the ion-permeation pathway. In several instances, including voltage-activated K+ (Kv) channels, ATP-activated P2X receptor channels, and transient receptor potential (TRP) channels, the ion-permeation pathways have been proposed to dilate in response to persistent activation, dynamically altering ion permeation. Here, we discuss evidence for dynamic ion selectivity, examples where ion selectivity filters exhibit structural plasticity, and opportunities to fill gaps in our current understanding.
摘要：
离子通道通过为离子提供水性途径以选择性地向下扩散其浓度梯度来建立跨细胞膜的电压梯度。任何给定通道对其有利离子的选择性通常被视为稳定的性质。在许多阳离子通道中，它是由离子渗透途径外端内的离子选择性过滤器确定的。在一些情况下，包括电压激活的K+(Kv)通道，ATP激活的P2X受体通道，和瞬时受体电位（TRP）通道，离子渗透途径已被提出为响应于持续活化而扩张，动态改变离子渗透。这里,我们讨论了动态离子选择性的证据，离子选择性过滤器表现出结构可塑性的例子，以及填补我们当前理解空白的机会。
