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Atomic force microscopy reveals the architecture of the epithelial sodium channel (ENaC).
Stewart AP, Haerteis S, Diakov A, Korbmacher C, Edwardson JM.
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The epithelial sodium channel (ENaC) is a member of the ENaC/degenerin superfamily. ENaC is a heteromultimer containing three homologous subunits (α, β, and γ); however, the subunit stoichiometry is still controversial. Here, we addressed this issue using atomic force microscopy imaging of complexes between isolated ENaC and antibodies/Fab fragments directed against specific epitope tags on the α-, β- and γ-subunits. We show that for α-, β- and γ-ENaC alone, pairs of antibodies decorate the channel at an angle of 120°, indicating that the individual subunits assemble as homotrimers. A similar approach demonstrates that αβγ-ENaC assembles as a heterotrimer containing one copy of each subunit. Intriguingly, all four subunit combinations also produce higher-order structures containing two or three individual trimers. The trimer-of-trimers organization would account for earlier reports that ENaC contains eight to nine subunits.
Anantharam,
Determination of epithelial Na+ channel subunit stoichiometry from single-channel conductances.
2007, Pubmed,
Xenbase
Anantharam,
Determination of epithelial Na+ channel subunit stoichiometry from single-channel conductances.
2007,
Pubmed
,
Xenbase Barrera,
Determination of the architecture of ionotropic receptors using AFM imaging.
2008,
Pubmed Barrera,
Atomic force microscopy imaging demonstrates that P2X2 receptors are trimers but that P2X6 receptor subunits do not oligomerize.
2005,
Pubmed Canessa,
Epithelial sodium channel related to proteins involved in neurodegeneration.
1993,
Pubmed
,
Xenbase Canessa,
Amiloride-sensitive epithelial Na+ channel is made of three homologous subunits.
1994,
Pubmed
,
Xenbase Carnally,
Direct visualization of the trimeric structure of the ASIC1a channel, using AFM imaging.
2008,
Pubmed Carnally,
Demonstration of a direct interaction between sigma-1 receptors and acid-sensing ion channels.
2010,
Pubmed Collier,
Identification of epithelial Na+ channel (ENaC) intersubunit Cl- inhibitory residues suggests a trimeric alpha gamma beta channel architecture.
2011,
Pubmed
,
Xenbase Coscoy,
The Phe-Met-Arg-Phe-amide-activated sodium channel is a tetramer.
1998,
Pubmed
,
Xenbase Diakov,
Cleavage in the {gamma}-subunit of the epithelial sodium channel (ENaC) plays an important role in the proteolytic activation of near-silent channels.
2008,
Pubmed
,
Xenbase Diakov,
A novel pathway of epithelial sodium channel activation involves a serum- and glucocorticoid-inducible kinase consensus motif in the C terminus of the channel's alpha-subunit.
2004,
Pubmed
,
Xenbase Dijkink,
The epithelial sodium channel (ENaC) is intracellularly located as a tetramer.
2002,
Pubmed
,
Xenbase Eskandari,
Number of subunits comprising the epithelial sodium channel.
1999,
Pubmed
,
Xenbase Firsov,
The heterotetrameric architecture of the epithelial sodium channel (ENaC).
1998,
Pubmed
,
Xenbase Haerteis,
The delta-subunit of the epithelial sodium channel (ENaC) enhances channel activity and alters proteolytic ENaC activation.
2009,
Pubmed
,
Xenbase Huber,
Functional characterization of a partial loss-of-function mutation of the epithelial sodium channel (ENaC) associated with atypical cystic fibrosis.
2010,
Pubmed
,
Xenbase Ismailov,
Triple-barrel organization of ENaC, a cloned epithelial Na+ channel.
1996,
Pubmed
,
Xenbase Jasti,
Structure of acid-sensing ion channel 1 at 1.9 A resolution and low pH.
2007,
Pubmed Kellenberger,
Epithelial sodium channel/degenerin family of ion channels: a variety of functions for a shared structure.
2002,
Pubmed Kobori,
The transient receptor potential channels TRPP2 and TRPC1 form a heterotetramer with a 2:2 stoichiometry and an alternating subunit arrangement.
2009,
Pubmed Korbmacher,
A calcium-activated and nucleotide-sensitive nonselective cation channel in M-1 mouse cortical collecting duct cells.
1995,
Pubmed Krueger,
Cholesterol depletion of the plasma membrane prevents activation of the epithelial sodium channel (ENaC) by SGK1.
2009,
Pubmed
,
Xenbase Loffing,
Regulated sodium transport in the renal connecting tubule (CNT) via the epithelial sodium channel (ENaC).
2009,
Pubmed Neaves,
Atomic force microscopy of the EcoKI Type I DNA restriction enzyme bound to DNA shows enzyme dimerization and DNA looping.
2009,
Pubmed Newbolt,
Membrane topology of an ATP-gated ion channel (P2X receptor).
1998,
Pubmed
,
Xenbase Rauh,
A mutation of the epithelial sodium channel associated with atypical cystic fibrosis increases channel open probability and reduces Na+ self inhibition.
2010,
Pubmed
,
Xenbase Rossier,
Activation of the epithelial sodium channel (ENaC) by serine proteases.
2009,
Pubmed Schneider,
Molecular weights of individual proteins correlate with molecular volumes measured by atomic force microscopy.
1998,
Pubmed Snyder,
Electrophysiological and biochemical evidence that DEG/ENaC cation channels are composed of nine subunits.
1998,
Pubmed
,
Xenbase Staruschenko,
Fluorescence resonance energy transfer analysis of subunit stoichiometry of the epithelial Na+ channel.
2004,
Pubmed Stockand,
Insight toward epithelial Na+ channel mechanism revealed by the acid-sensing ion channel 1 structure.
2008,
Pubmed Waldmann,
Molecular cloning and functional expression of a novel amiloride-sensitive Na+ channel.
1995,
Pubmed
,
Xenbase WELCH,
The generalisation of student's problems when several different population variances are involved.
1947,
Pubmed Zhou,
Human alpha4beta2 acetylcholine receptors formed from linked subunits.
2003,
Pubmed
,
Xenbase
