Determinants of cation transport selectivity: Equilibrium binding and transport kinetics

The crystal structures of channels and transporters reveal the chemical nature of ion-binding sites and, thereby, constrain mechanistic models for their transport processes. However, these structures, in and of themselves, do not reveal equilibrium selectivity or transport preferences, which can be discerned only from various functional assays. In this Review, I explore the relationship between cation transport protein structures, equilibrium binding measurements, and ion transport selectivity. The primary focus is on K+-selective channels and nonselective cation channels because they have been extensively studied both functionally and structurally, but the principles discussed are relevant to other transport proteins and molecules.

• Publication year

  2015

• Venue

  The Journal of General Physiology

• Publication date

  2015-07-01

• Fields of study

  Biology, Medicine, Chemistry

• Identifiers
  DOI 10.1085/jgp.201511371PMID 26078056PMCID 4485025
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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