Related Experiment Video
Updated: Jun 9, 2026
06:58
Evaluation of LC3-II Release via Extracellular Vesicles in Relation to the Accumulation of Intracellular LC3-positive Vesicles
Published on: October 18, 2024
Autophagy-independent LC3 function in vesicular traffic.
Cornelis A M de Haan1, Maurizio Molinari, Fulvio Reggiori
1Virology Division, Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, Netherlands. C.A.M.deHaan@uu.nl
Autophagy
|September 4, 2010
Summary
The endoplasmic reticulum (ER) uses EDEMosomes to regulate protein degradation. Coronaviruses hijack ER membranes to form double-membrane vesicles (DMVs) for replication, but their assembly mechanism remains unclear.
Area of Science:
- Cell Biology
- Virology
- Molecular Biology
Background:
- Protein folding in the endoplasmic reticulum (ER) is error-prone, necessitating both folding and ER-associated degradation (ERAD) systems.
- ERAD regulators like EDEM1 and OS-9 are cleared via EDEMosomes to prevent premature degradation, a process termed ERAD tuning, distinct from macroautophagy.
- Positive-strand RNA coronaviruses (CoVs), including SARS-CoV and MHV, induce double-membrane vesicles (DMVs) in infected cells for viral replication.
Purpose of the Study:
- To investigate the mechanism of EDEM1 and OS-9 turnover in ERAD tuning.
- To elucidate the biogenesis of coronavirus-induced double-membrane vesicles (DMVs).
Main Methods:
- The study likely involves molecular biology techniques to analyze protein turnover and vesicle formation.
- Comparative analysis of ERAD tuning and DMV formation mechanisms.
Main Results:
- EDEM1 and OS-9 undergo rapid turnover through ERAD tuning, a process with similarities to, yet distinct from, macroautophagy.
- Coronaviruses induce DMVs, essential for viral replication, by hijacking ER-derived membranes.
- The precise mechanism of DMV assembly remains elusive.
Conclusions:
- ERAD tuning is a crucial regulatory mechanism for protein degradation within the ER.
- Understanding DMV biogenesis is key to comprehending coronavirus replication strategies.
- Further research is needed to fully unravel the assembly pathways of these viral replication structures.
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