Structural correlates of selectivity and inactivation in potassium channels

• Published in: Biochimica et biophysica acta Vol. 1818; no. 2; pp. 272 - 285
• Main Authors: McCoy, Jason G., Nimigean, Crina M.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2012
• Subjects: Amino Acid Sequence; Animals; Humans; Inactivation; KCSA; Models, Molecular; Molecular Sequence Data; Potassium channel; Potassium Channels - chemistry; Potassium Channels - genetics; Potassium Channels - metabolism; Protein Structure, Secondary; Selectivity; Sequence Alignment; Selectivity; Inactivation; KCSA; Potassium channel
• ISSN: 0005-2736; 0006-3002; 1879-2642; 0006-3002
• DOI: 10.1016/j.bbamem.2011.09.007

Potassium channels are involved in a tremendously diverse range of physiological applications requiring distinctly different functional properties. Not surprisingly, the amino acid sequences for these proteins are diverse as well, except for the region that has been ordained the “selectivity filter”. The goal of this review is to examine our current understanding of the role of the selectivity filter and regions adjacent to it in specifying selectivity as well as its role in gating/inactivation and possible mechanisms by which these processes are coupled. Our working hypothesis is that an amino acid network behind the filter modulates selectivity in channels with the same signature sequence while at the same time affecting channel inactivation properties. This article is part of a Special Issue entitled: Membrane protein structure and function. ► We review the role of the selectivity filter region in selectivity and inactivation. ► We focus on three different families of potassium channels: Kv, Kir, and KCa. ► Residues near the filter modulate selectivity and inactivation.