Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
45
pubmed:dateCreated
2010-11-1
pubmed:abstractText
The epithelial Na(+) channel (ENaC) mediates the rate-limiting step in transepithelial Na(+) transport in the distal segments of the nephron and in the lung. ENaC subunits are cleaved by proteases, resulting in channel activation due to the release of inhibitory tracts. Peptides derived from these tracts inhibit channel activity. The mechanism by which these intrinsic inhibitory tracts reduce channel activity is unknown, as are the sites where these tracts interact with other residues within the channel. We performed site-directed mutagenesis in large portions of the predicted periphery of the extracellular region of the ? subunit and measured the effect of mutations on an 8-residue inhibitory tract-derived peptide. Our data show that the inhibitory peptide likely binds to specific residues within the finger and thumb domains of ENaC. Pairwise interactions between the peptide and the channel were identified by double mutant cycle experiments. Our data suggest that the inhibitory peptide has a specific peptide orientation within its binding site. Extended to the intrinsic inhibitory tract, our data suggest that proteases activate ENaC by removing residues that bind at the finger-thumb domain interface.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
5
pubmed:volume
285
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35216-23
pubmed:dateRevised
2011-11-7
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Allosteric inhibition of the epithelial Na+ channel through peptide binding at peripheral finger and thumb domains.
pubmed:affiliation
Departments of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural