About: Summary Proteins that are concentrated in specific compartments of the endomembrane system in order to exert their organelle-specific function must possess specific localization signals that prevent their transport to distal regions of the exocytic pathway. Some resident proteins of the endoplasmic reticulum (ER) that are known to escape with low efficiency from this organelle to a post ER compartment are recognized by a recycling receptor and brought back to their site of residence. Other ER proteins, however, appear to be retained in the ER by mechanisms that operate in the organelle itself. The mammalian oligosaccharyltransferase (OST) is a protein complex that effects the cotranslational N-glycosylation of newly synthesized polypeptides, and is composed of at least four rough ER-specific membrane proteins: ribophorins I and II (RI and RII), OST48, and Dad1. The mechanism(s) by which the subunits of this complex are retained in the ER are not well understood. In an effort to identify the domains within RII responsible for its ER localization we have studied the fate of chimeric proteins in which one or more RII domains were replaced by the corresponding ones of the Tac antigen, the latter being a well characterized plasma membrane protein that lacks intrinsic ER retention signals and serves to provide a neutral framework for the identification of retention signals in other proteins. We found that the luminal domain of RII by itself does not contain retention information, while the cytoplasmic and transmembrane domains contain independent ER localization signals. We also show that the retention function of the transmembrane domain is strengthened by the presence of a flanking luminal region consisting of 15 amino acids.   Goto Sponge  NotDistinct  Permalink

An Entity of Type : fabio:Abstract, within Data Space : wasabi.inria.fr associated with source document(s)

AttributesValues
type
value
  • Summary Proteins that are concentrated in specific compartments of the endomembrane system in order to exert their organelle-specific function must possess specific localization signals that prevent their transport to distal regions of the exocytic pathway. Some resident proteins of the endoplasmic reticulum (ER) that are known to escape with low efficiency from this organelle to a post ER compartment are recognized by a recycling receptor and brought back to their site of residence. Other ER proteins, however, appear to be retained in the ER by mechanisms that operate in the organelle itself. The mammalian oligosaccharyltransferase (OST) is a protein complex that effects the cotranslational N-glycosylation of newly synthesized polypeptides, and is composed of at least four rough ER-specific membrane proteins: ribophorins I and II (RI and RII), OST48, and Dad1. The mechanism(s) by which the subunits of this complex are retained in the ER are not well understood. In an effort to identify the domains within RII responsible for its ER localization we have studied the fate of chimeric proteins in which one or more RII domains were replaced by the corresponding ones of the Tac antigen, the latter being a well characterized plasma membrane protein that lacks intrinsic ER retention signals and serves to provide a neutral framework for the identification of retention signals in other proteins. We found that the luminal domain of RII by itself does not contain retention information, while the cytoplasmic and transmembrane domains contain independent ER localization signals. We also show that the retention function of the transmembrane domain is strengthened by the presence of a flanking luminal region consisting of 15 amino acids.
subject
  • Endoplasmic reticulum
  • Animal anatomy
  • Cell anatomy
  • EC 2.4.1
  • Membrane biology
part of
is abstract of
is hasSource of
Faceted Search & Find service v1.13.91 as of Mar 24 2020


Alternative Linked Data Documents: Sponger | ODE     Content Formats:       RDF       ODATA       Microdata      About   
This material is Open Knowledge   W3C Semantic Web Technology [RDF Data]
OpenLink Virtuoso version 07.20.3229 as of Jul 10 2020, on Linux (x86_64-pc-linux-gnu), Single-Server Edition (94 GB total memory)
Data on this page belongs to its respective rights holders.
Virtuoso Faceted Browser Copyright © 2009-2025 OpenLink Software