Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
2005-5-9
pubmed:abstractText
Mutations in the human ether-a-go-go-related gene (hERG) cause chromosome 7-linked long QT syndrome type II (LQT2). We have shown previously that LQT2 mutations lead to endoplasmic reticulum (ER) retention and rapid degradation of mutant hERG proteins. In this study we examined the role of the ubiquitin-proteasome pathway in the degradation of the LQT2 mutation Y611H. We showed that proteasome inhibitors N-acetyl-L-leucyl-L-leucyl-L-norleucinal and lactacystin but not lysosome inhibitor leupeptin inhibited the degradation of Y611H mutant channels. In addition, ER mannosidase I inhibitor kifunensine and down-regulation of EDEM (ER degradation-enhancing alpha-mannosidase-like protein) also suppressed the degradation of Y611H mutant channels. Proteasome inhibition but not mannosidase inhibition led to the accumulation of full-length hERG protein in the cytosol. The hERG protein accumulated in the cytosol was deglycosylated. Proteasome inhibition also resulted in the accumulation of polyubiquitinated hERG channels. These results suggest that the degradation of LQT2 mutant channels is mediated by the cytosolic proteasome in a process that involves mannose trimming, polyubiquitination, and deglycosylation of mutant channels.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Acetylcysteine, http://linkedlifedata.com/resource/pubmed/chemical/Alkaloids, http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Proteinase Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Green Fluorescent Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Leupeptins, http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels, http://linkedlifedata.com/resource/pubmed/chemical/Proteasome Endopeptidase Complex, http://linkedlifedata.com/resource/pubmed/chemical/Ribonucleases, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin, http://linkedlifedata.com/resource/pubmed/chemical/acetylleucyl-leucyl-norleucinal, http://linkedlifedata.com/resource/pubmed/chemical/kifunensine, http://linkedlifedata.com/resource/pubmed/chemical/lactacystin, http://linkedlifedata.com/resource/pubmed/chemical/leupeptin
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
19419-25
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15760896-Acetylcysteine, pubmed-meshheading:15760896-Alkaloids, pubmed-meshheading:15760896-Blotting, Western, pubmed-meshheading:15760896-Cell Line, pubmed-meshheading:15760896-Cell Membrane, pubmed-meshheading:15760896-Cysteine Proteinase Inhibitors, pubmed-meshheading:15760896-Cytosol, pubmed-meshheading:15760896-Down-Regulation, pubmed-meshheading:15760896-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:15760896-Endoplasmic Reticulum, pubmed-meshheading:15760896-Enzyme Inhibitors, pubmed-meshheading:15760896-Glycosylation, pubmed-meshheading:15760896-Green Fluorescent Proteins, pubmed-meshheading:15760896-Humans, pubmed-meshheading:15760896-Immunoprecipitation, pubmed-meshheading:15760896-Leupeptins, pubmed-meshheading:15760896-Long QT Syndrome, pubmed-meshheading:15760896-Mutation, pubmed-meshheading:15760896-Potassium Channels, pubmed-meshheading:15760896-Proteasome Endopeptidase Complex, pubmed-meshheading:15760896-Ribonucleases, pubmed-meshheading:15760896-Subcellular Fractions, pubmed-meshheading:15760896-Time Factors, pubmed-meshheading:15760896-Transfection, pubmed-meshheading:15760896-Ubiquitin
pubmed:year
2005
pubmed:articleTitle
Degradation of trafficking-defective long QT syndrome type II mutant channels by the ubiquitin-proteasome pathway.
pubmed:affiliation
Division of Molecular Medicine, Department of Medicine, Oregon Health and Science University, Portland, Oregon 97239, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural