Rim aperture of yeast autophagic membranes balances cargo inclusion with vesicle maturation.
Dev Cell
; 59(7): 911-923.e4, 2024 Apr 08.
Article
in En
| MEDLINE
| ID: mdl-38447569
ABSTRACT
Autophagy eliminates cytoplasmic material by engulfment in membranous vesicles targeted for lysosome degradation. Nonselective autophagy coordinates sequestration of bulk cargo with the growth of the isolation membrane (IM) in a yet-unknown manner. Here, we show that in the budding yeast Saccharomyces cerevisiae, IMs expand while maintaining a rim sufficiently wide for sequestration of large cargo but tight enough to mature in due time. An obligate complex of Atg24/Snx4 with Atg20 or Snx41 assembles locally at the rim in a spatially extended manner that specifically depends on autophagic PI(3)P. This assembly stabilizes the open rim to promote autophagic sequestration of large cargo in correlation with vesicle expansion. Moreover, constriction of the rim by the PI(3)P-dependent Atg2-Atg18 complex and clearance of PI(3)P by Ymr1 antagonize rim opening to promote autophagic maturation and consumption of small cargo. Tight regulation of membrane rim aperture by PI(3)P thus couples the mechanism and physiology of nonselective autophagy.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Saccharomyces cerevisiae
/
Saccharomyces cerevisiae Proteins
Language:
En
Journal:
Dev Cell
Journal subject:
EMBRIOLOGIA
Year:
2024
Document type:
Article
Affiliation country:
Israel