20 min listen
Parallel phospholipid transfer by Vps13 and Atg2 determines autophagosome biogenesis dynamics
Parallel phospholipid transfer by Vps13 and Atg2 determines autophagosome biogenesis dynamics
ratings:
Length:
20 minutes
Released:
Nov 10, 2022
Format:
Podcast episode
Description
Link to bioRxiv paper:
http://biorxiv.org/cgi/content/short/2022.11.10.516013v1?rss=1
Authors: Dabrowski, R., Tulli, S., Graef, M.
Abstract:
During autophagy, rapid membrane assembly expands small phagophores into large double-membrane autophagosomes. Theoretical modelling predicts the majority of autophagosomal phospholipids is derived from highly efficient non-vesicular phospholipid transfer (PLT) across phagophore-ER contacts (PERCS). Currently, the phagophore-ER tether Atg2 is the only PLT protein known to drive phagophore expansion in vivo. Here, our quantitative live-cell-imaging analysis reveals poor correlation between duration and size of forming autophagosomes and number of Atg2 molecules at PERCS of starving yeast cells. Strikingly, we find Atg2-mediated PLT is non-rate-limiting for autophagosome biogenesis, because membrane tether and PLT protein Vps13 localizes to the rim and promotes expansion of phagophores in parallel with Atg2. In the absence of Vps13, the number of Atg2 molecules at PERCS determines duration and size of forming autophagosomes with an apparent in vivo transfer rate of ~200 phospholipids per Atg2 molecule and second. We propose conserved PLT proteins cooperate in channeling phospholipids across organelle contact sites for non-rate-limiting membrane assembly during autophagosome biogenesis.
Copy rights belong to original authors. Visit the link for more info
Podcast created by Paper Player, LLC
http://biorxiv.org/cgi/content/short/2022.11.10.516013v1?rss=1
Authors: Dabrowski, R., Tulli, S., Graef, M.
Abstract:
During autophagy, rapid membrane assembly expands small phagophores into large double-membrane autophagosomes. Theoretical modelling predicts the majority of autophagosomal phospholipids is derived from highly efficient non-vesicular phospholipid transfer (PLT) across phagophore-ER contacts (PERCS). Currently, the phagophore-ER tether Atg2 is the only PLT protein known to drive phagophore expansion in vivo. Here, our quantitative live-cell-imaging analysis reveals poor correlation between duration and size of forming autophagosomes and number of Atg2 molecules at PERCS of starving yeast cells. Strikingly, we find Atg2-mediated PLT is non-rate-limiting for autophagosome biogenesis, because membrane tether and PLT protein Vps13 localizes to the rim and promotes expansion of phagophores in parallel with Atg2. In the absence of Vps13, the number of Atg2 molecules at PERCS determines duration and size of forming autophagosomes with an apparent in vivo transfer rate of ~200 phospholipids per Atg2 molecule and second. We propose conserved PLT proteins cooperate in channeling phospholipids across organelle contact sites for non-rate-limiting membrane assembly during autophagosome biogenesis.
Copy rights belong to original authors. Visit the link for more info
Podcast created by Paper Player, LLC
Released:
Nov 10, 2022
Format:
Podcast episode
Titles in the series (100)
A genome-wide CRISPR interference screen using an engineered trafficking biosensor reveals a role for RME-8 in opioid receptor regulation by PaperPlayer biorxiv cell biology