Aug 3, 2020
ERdj8 governs the size of autophagosomes during the formation process
Journal of Cell Biology
- Volume
- 219
- Number
- 8
- Language
- Publishing type
- Research paper (scientific journal)
- DOI
- 10.1083/jcb.201903127
- Publisher
- Rockefeller University Press
In macroautophagy, membrane structures called autophagosomes engulf substrates and deliver them for lysosomal degradation. Autophagosomes enwrap a variety of targets with diverse sizes, from portions of cytosol to larger organelles. However, the mechanism by which autophagosome size is controlled remains elusive. We characterized a novel ER membrane protein, ERdj8, in mammalian cells. ERdj8 localizes to a meshwork-like ER subdomain along with phosphatidylinositol synthase (PIS) and autophagy-related (Atg) proteins. ERdj8 overexpression extended the size of the autophagosome through its DnaJ and TRX domains. ERdj8 ablation resulted in a defect in engulfing larger targets. C. elegans, in which the ERdj8 orthologue dnj-8 was knocked down, could perform autophagy on smaller mitochondria derived from the paternal lineage but not the somatic mitochondria. Thus, ERdj8 may play a critical role in autophagosome formation by providing the capacity to target substrates of diverse sizes for degradation.
- Link information
- ID information
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- DOI : 10.1083/jcb.201903127
- ISSN : 0021-9525
- eISSN : 1540-8140