Linked Life Data

11067926

Source:http://linkedlifedata.com/resource/pubmed/id/11067926

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2000-11-21
pubmed:abstractText
The high affinity IgE receptor (FcepsilonRI) is a multisubunit complex comprised of either alphagamma(2) or alphabetagamma(2) chains. The cotranslational assembly of the IgE-binding alpha-chain with a dimer of gamma-chains occurs in a highly controlled manner and is proposed to involve masking of a dilysine motif present at the cytoplasmic C terminus of the FcepsilonRI alpha-chain that targets localization of this subunit to the endoplasmic reticulum (ER). Here, we show that ER quality control modulates export from the ER of newly synthesized alphagamma(2) and alphabetagamma(2) receptors. We demonstrate that the presence of untrimmed N-linked core glycans (Glc(3)Man(9)GlcNAc(2)) on the FcepsilonRI alpha-chain activates the ER quality control mechanism to retain this subunit in the ER, despite the presence of gamma-chains. At the same time, the untrimmed, ER-localized alpha-chain exhibits IgE-binding activity, suggesting that FcepsilonRI alpha-chain folding occurs before constitutive glucose trimming. In additional experiments, we demonstrate that cell surface expression of an alpha-chain C-terminal truncation mutant is also dependent on glucose trimming, but not on gamma-chain coexpression. We suggest that glucosidase trimming of terminal glucose residues is a critical control step in the export of FcepsilonRIalpha from the ER. Finally, we show that the constitutive ER FcepsilonRI alpha-chain, expressed in the absence of the other FcepsilonRI subunits, associates with the ER lectin-like chaperone calnexin, but not the structurally similar ER chaperone calreticulin, presumably through interaction with monoglucosylated alpha-chain ER glycoforms.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
165
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5686-94
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11067926-Animals, pubmed-meshheading:11067926-Antibodies, Monoclonal, pubmed-meshheading:11067926-Biological Transport, pubmed-meshheading:11067926-CHO Cells, pubmed-meshheading:11067926-Calcium-Binding Proteins, pubmed-meshheading:11067926-Calnexin, pubmed-meshheading:11067926-Carbohydrate Conformation, pubmed-meshheading:11067926-Cell Membrane, pubmed-meshheading:11067926-Cricetinae, pubmed-meshheading:11067926-Cytoplasm, pubmed-meshheading:11067926-Endoplasmic Reticulum, pubmed-meshheading:11067926-Glucose, pubmed-meshheading:11067926-Glycoside Hydrolases, pubmed-meshheading:11067926-Glycosylation, pubmed-meshheading:11067926-HeLa Cells, pubmed-meshheading:11067926-Humans, pubmed-meshheading:11067926-Immunoglobulin E, pubmed-meshheading:11067926-Molecular Chaperones, pubmed-meshheading:11067926-Plasmids, pubmed-meshheading:11067926-Polysaccharides, pubmed-meshheading:11067926-Precipitin Tests, pubmed-meshheading:11067926-Protein Binding, pubmed-meshheading:11067926-Protein Processing, Post-Translational, pubmed-meshheading:11067926-Receptors, IgE, pubmed-meshheading:11067926-Sequence Deletion, pubmed-meshheading:11067926-Subcellular Fractions, pubmed-meshheading:11067926-Transfection
pubmed:year
2000
pubmed:articleTitle
Export of the high affinity IgE receptor from the endoplasmic reticulum depends on a glycosylation-mediated quality control mechanism.
pubmed:affiliation
Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't