Dilation of Ion Selectivity Filters in Cation Channels

Overview

Journal Trends Biochem Sci

Specialty Biochemistry

Date 2024 Mar 21

PMID 38514273

Authors

Kate Huffer

Xiao-Feng Tan

Ana I Fernandez-Marino

Surbhi Dhingra

Kenton J Swartz

Affiliations

Soon will be listed here.

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.

Citing Articles

Structure of the human K13.1 channel reveals a hydrophilic pore restriction and lipid cofactor site.

Roy-Chowdhury S, Jang S, Abderemane-Ali F, Naughton F, Grabe M, Minor Jr D Nat Struct Mol Biol. 2025; .

PMID: 40011746 DOI: 10.1038/s41594-024-01476-3.

Structure of the human K13.1(THIK-1) channel reveals a novel hydrophilic pore restriction and lipid cofactor site.

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