Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2000-11-6
pubmed:abstractText
Ventricular fibrillation leading to sudden cardiac death can occur even in the absence of structural heart disease. One form of this so-called idiopathic ventricular fibrillation (IVF) is characterized by ST segment elevation (STE) in the electrocardiogram. Recently we found that IVF with STE is linked to mutations of SCN5A, the gene encoding the cardiac sodium channel alpha -subunit. Two types of defects were identified: loss-of-function mutations that severely truncate channel proteins and missense mutations (e.g. a double mutation, R1232W and T1620M) that cause only minor changes in channel gating. Here we show that co-expression of the R1232W+T1620M missense mutant alpha -subunits in a mammalian cell line stably transfected with human sodium channel beta(1)-subunits results in a phenotype similar to that of the truncation mutants. In the presence of beta(1)subunits the expression of both ionic currents and alpha -subunit-specific, immunoreactive protein was markedly suppressed after transfection of mutant, but not wild-type alpha -subunits when cells were incubated at physiological temperature. Expression was partially restored by incubation at reduced temperatures. Our results reconcile two classes of IVF mutations and support the notion that a reduction in the amplitude of voltage-gated sodium conductance is the primary cause of IVF.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-2828
pubmed:author
pubmed:copyrightInfo
Copyright 2000 Academic Press.
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1873-84
pubmed:dateRevised
2011-7-22
pubmed:meshHeading
pubmed-meshheading:11013131-Animals, pubmed-meshheading:11013131-Cell Line, pubmed-meshheading:11013131-DNA, Complementary, pubmed-meshheading:11013131-Electrophysiology, pubmed-meshheading:11013131-Humans, pubmed-meshheading:11013131-Immunoblotting, pubmed-meshheading:11013131-Ions, pubmed-meshheading:11013131-Kinetics, pubmed-meshheading:11013131-Models, Biological, pubmed-meshheading:11013131-Mutagenesis, Site-Directed, pubmed-meshheading:11013131-Mutation, Missense, pubmed-meshheading:11013131-Oocytes, pubmed-meshheading:11013131-Phenotype, pubmed-meshheading:11013131-Protein Folding, pubmed-meshheading:11013131-Protein Structure, Secondary, pubmed-meshheading:11013131-Protein Structure, Tertiary, pubmed-meshheading:11013131-Sodium Channel Blockers, pubmed-meshheading:11013131-Sodium Channels, pubmed-meshheading:11013131-Temperature, pubmed-meshheading:11013131-Time Factors, pubmed-meshheading:11013131-Transfection, pubmed-meshheading:11013131-Ventricular Fibrillation, pubmed-meshheading:11013131-Xenopus
pubmed:year
2000
pubmed:articleTitle
Functional suppression of sodium channels by beta(1)-subunits as a molecular mechanism of idiopathic ventricular fibrillation.
pubmed:affiliation
Rammelkamp Center for Education and Research, Case Western Reserve University, Cleveland, OH 44109, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't