Ion selectivity in a semisynthetic K+ channel locked in the conductive conformation

Francis Valiyaveetil, Manuel Leonetti, Tom W. Muir, Roderick MacKinnon

Research output: Contribution to journalArticle

105 Citations (Scopus)

Abstract

Potassium channels are K+-selective protein pores in cell membrane. The selectivity filter is the functional unit that allows K + channels to distinguish potassium (K+) and sodium (Na+) ions. The filter's structure depends on whether K+ or Na+ ions are bound inside it. We synthesized a K+ channel containing the D-enantiomer of alanine in place of a conserved glycine and found by x-ray crystallography that its filter maintains the K+ (conductive) structure in the presence of Na+ and very low concentrations of K+. This channel conducts Na+ in the absence of K+ but not in the presence of K+. These findings demonstrate that the ability of the channel to adapt its structure differently to K+ and Na+ is a fundamental aspect of ion selectivity, as is the ability of multiple K+ ions to compete effectively with Na+ for the conductive filter.

Original languageEnglish (US)
Pages (from-to)1004-1007
Number of pages4
JournalScience
Volume314
Issue number5801
DOIs
StatePublished - Nov 10 2006

Fingerprint

Ions
Porins
Crystallography
Potassium Channels
Alanine
Glycine
Potassium
Sodium
Cell Membrane
X-Rays
protein K

ASJC Scopus subject areas

  • General

Cite this

Ion selectivity in a semisynthetic K+ channel locked in the conductive conformation. / Valiyaveetil, Francis; Leonetti, Manuel; Muir, Tom W.; MacKinnon, Roderick.

In: Science, Vol. 314, No. 5801, 10.11.2006, p. 1004-1007.

Research output: Contribution to journalArticle

Valiyaveetil, Francis ; Leonetti, Manuel ; Muir, Tom W. ; MacKinnon, Roderick. / Ion selectivity in a semisynthetic K+ channel locked in the conductive conformation. In: Science. 2006 ; Vol. 314, No. 5801. pp. 1004-1007.
@article{9bd5b410ef95477cbe5635d258073977,
title = "Ion selectivity in a semisynthetic K+ channel locked in the conductive conformation",
abstract = "Potassium channels are K+-selective protein pores in cell membrane. The selectivity filter is the functional unit that allows K + channels to distinguish potassium (K+) and sodium (Na+) ions. The filter's structure depends on whether K+ or Na+ ions are bound inside it. We synthesized a K+ channel containing the D-enantiomer of alanine in place of a conserved glycine and found by x-ray crystallography that its filter maintains the K+ (conductive) structure in the presence of Na+ and very low concentrations of K+. This channel conducts Na+ in the absence of K+ but not in the presence of K+. These findings demonstrate that the ability of the channel to adapt its structure differently to K+ and Na+ is a fundamental aspect of ion selectivity, as is the ability of multiple K+ ions to compete effectively with Na+ for the conductive filter.",
author = "Francis Valiyaveetil and Manuel Leonetti and Muir, {Tom W.} and Roderick MacKinnon",
year = "2006",
month = "11",
day = "10",
doi = "10.1126/science.1133415",
language = "English (US)",
volume = "314",
pages = "1004--1007",
journal = "Science",
issn = "0036-8075",
publisher = "American Association for the Advancement of Science",
number = "5801",

}

TY - JOUR

T1 - Ion selectivity in a semisynthetic K+ channel locked in the conductive conformation

AU - Valiyaveetil, Francis

AU - Leonetti, Manuel

AU - Muir, Tom W.

AU - MacKinnon, Roderick

PY - 2006/11/10

Y1 - 2006/11/10

N2 - Potassium channels are K+-selective protein pores in cell membrane. The selectivity filter is the functional unit that allows K + channels to distinguish potassium (K+) and sodium (Na+) ions. The filter's structure depends on whether K+ or Na+ ions are bound inside it. We synthesized a K+ channel containing the D-enantiomer of alanine in place of a conserved glycine and found by x-ray crystallography that its filter maintains the K+ (conductive) structure in the presence of Na+ and very low concentrations of K+. This channel conducts Na+ in the absence of K+ but not in the presence of K+. These findings demonstrate that the ability of the channel to adapt its structure differently to K+ and Na+ is a fundamental aspect of ion selectivity, as is the ability of multiple K+ ions to compete effectively with Na+ for the conductive filter.

AB - Potassium channels are K+-selective protein pores in cell membrane. The selectivity filter is the functional unit that allows K + channels to distinguish potassium (K+) and sodium (Na+) ions. The filter's structure depends on whether K+ or Na+ ions are bound inside it. We synthesized a K+ channel containing the D-enantiomer of alanine in place of a conserved glycine and found by x-ray crystallography that its filter maintains the K+ (conductive) structure in the presence of Na+ and very low concentrations of K+. This channel conducts Na+ in the absence of K+ but not in the presence of K+. These findings demonstrate that the ability of the channel to adapt its structure differently to K+ and Na+ is a fundamental aspect of ion selectivity, as is the ability of multiple K+ ions to compete effectively with Na+ for the conductive filter.

UR - http://www.scopus.com/inward/record.url?scp=33750968787&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33750968787&partnerID=8YFLogxK

U2 - 10.1126/science.1133415

DO - 10.1126/science.1133415

M3 - Article

C2 - 17095703

AN - SCOPUS:33750968787

VL - 314

SP - 1004

EP - 1007

JO - Science

JF - Science

SN - 0036-8075

IS - 5801

ER -