Linked Life Data

15901736

Source:http://linkedlifedata.com/resource/pubmed/id/15901736

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
28
pubmed:dateCreated
2005-7-11
pubmed:abstractText
Increasing evidence suggests that the folding and maturation of monomeric proteins and assembly of multimeric protein complexes in the endoplasmic reticulum (ER) may be inefficient not only for mutants that carry changes in the primary structure but also for wild type proteins. In the present study, we demonstrate that the rat luteinizing hormone receptor, a G protein-coupled receptor, is one of these proteins that matures inefficiently and appears to be very prone to premature degradation. A substantial portion of the receptors in stably transfected human embryonic kidney 293 cells existed in immature form of M(r) 73,000, containing high mannose-type N-linked glycans. In metabolic pulse-chase studies, only approximately 20% of these receptor precursors were found to gain hormone binding ability and matured to a form of M(r) 90,000, containing bi- and multiantennary sialylated N-linked glycans. The rest had a propensity to form disulfide-bonded complexes with a M(r) 120,000 protein in the ER membrane and were eventually targeted for degradation in proteasomes. The number of membrane-bound receptor precursors increased when proteasomal degradation was inhibited, and no cytosolic receptor forms were detected, suggesting that retrotranslocation of the misfolded/incompletely folded receptors is tightly coupled to proteasomal function. Furthermore, a proteasomal blockade was found to increase the number of receptors that were capable of hormone binding. Thus, these results raise the interesting possibility that luteinizing hormone receptor expression at the cell surface may be controlled at the ER level by regulating the number of newly synthesized proteins that will mature and escape the ER quality control and premature degradation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26622-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15901736-Acetylcysteine, pubmed-meshheading:15901736-Animals, pubmed-meshheading:15901736-Blotting, Western, pubmed-meshheading:15901736-Cell Line, pubmed-meshheading:15901736-Cell Membrane, pubmed-meshheading:15901736-Cytosol, pubmed-meshheading:15901736-DNA, pubmed-meshheading:15901736-Disulfides, pubmed-meshheading:15901736-Electrophoresis, Gel, Two-Dimensional, pubmed-meshheading:15901736-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:15901736-Endoplasmic Reticulum, pubmed-meshheading:15901736-Gene Expression Regulation, pubmed-meshheading:15901736-Humans, pubmed-meshheading:15901736-Immunoblotting, pubmed-meshheading:15901736-Immunoprecipitation, pubmed-meshheading:15901736-Ligands, pubmed-meshheading:15901736-Male, pubmed-meshheading:15901736-Oligosaccharides, pubmed-meshheading:15901736-Polysaccharides, pubmed-meshheading:15901736-Proteasome Endopeptidase Complex, pubmed-meshheading:15901736-Protein Binding, pubmed-meshheading:15901736-Rats, pubmed-meshheading:15901736-Rats, Sprague-Dawley, pubmed-meshheading:15901736-Receptors, LH, pubmed-meshheading:15901736-Subcellular Fractions, pubmed-meshheading:15901736-Time Factors, pubmed-meshheading:15901736-Transfection
pubmed:year
2005
pubmed:articleTitle
Inefficient maturation of the rat luteinizing hormone receptor. A putative way to regulate receptor numbers at the cell surface.
pubmed:affiliation
Biocenter Oulu and Department of Anatomy and Cell Biology, University of Oulu, Finland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't