| Added by | pmartino |
|---|---|
| Group name | EquipePM |
| Item Type | Journal Article |
| Title | Proteasome 19S RP and translation preinitiation complexes are secreted within exosomes upon serum starvation |
| Creator | Bec et al. |
| Author | Nicole Bec |
| Author | Anne Bonhoure |
| Author | Laurent Henry |
| Author | Laurence Berry |
| Author | Christian Larroque |
| Author | Olivier Coux |
| Author | Pierre-Emmanuel Stoebner |
| Author | Michel Vidal |
| Abstract | The aim of our study was to investigate the impact of macroautophagy on exosome secretion. Exosomes are small membrane vesicles released in the extracellular space upon fusion of multivesicular endosomes with the plasma membrane. They were initially discovered as a way to remodel the reticulocyte plasma membrane before entering the blood circulation (Current Opinion in Hematology 2010, 17:177-183) and are now essentially studied as mediators of intercellular communication. Using iTRAQ proteomics, we compared the protein composition of purified exosomes secreted by cells impaired or not for macroautophagy by Atg5 depletion, during serum starvation conditions or complete medium culture. We show that the absence of serum modifies exosomal content, especially inducing secretion of two cytoplasmic protein complexes, namely proteasomal 19S regulatory particle (RP) and components of non-canonical translation preinitiation complex (PIC). This process is enhanced when autophagy is impaired by Atg5 depletion. Moreover, we show that the proteasome 20S core particle (CP) is released in the extracellular space. However, in striking contrast to what seen for its 19S RP regulator, release is independent of the exosomal vesicles, Atg5 expression and cell culture conditions. Exosome secretion can thus be considered as a cell process that participates in and reflects cell homeostasis, and care must be taken when studying potential extracellular function of exosomes due to the possible co-purification of proteasome 20S CP. This article is protected by copyright. All rights reserved. |
| Publication | Traffic (Copenhagen, Denmark) |
| Date | May 01, 2019 |
| Journal Abbr | Traffic |
| Language | eng |
| DOI | 10.1111/tra.12653 |
| ISSN | 1600-0854 |
| Library Catalog | PubMed |
| Call Number | IMPACT: 4.4 |
| Extra | PMID: 31042005 IMPACT: 4.4 |
| Tags | Autophagy, Autophagy-Related Protein 5, Cell Line, Tumor, Culture Media, Serum-Free, Cytoplasmic Granules, endosomal microautophagy, Eukaryotic Initiation Factors, Exosomes, Humans, original, PBVOL, Proteasome Endopeptidase Complex, Protein Transport, Proteome, Ribosomal Proteins, translation preinitiation complex, Vesicular Transport Proteins |
| Date Added | 2019/05/22 - 08:48:18 |
| Date Modified | 2021/03/05 - 10:43:15 |
| Notes and Attachments | Full Text (Attachment) PubMed entry (Attachment) PubMed entry (Attachment) |
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