Organelle size control - increasing vacuole content activates SNAREs to augment organelle volume through homotypic fusion.
Details
State: Public
Version: Final published version
Serval ID
serval:BIB_6E205EDE96C6
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Organelle size control - increasing vacuole content activates SNAREs to augment organelle volume through homotypic fusion.
Journal
Journal of Cell Science
ISSN
1477-9137 (Electronic)
ISSN-L
0021-9533
Publication state
Published
Issued date
2016
Volume
129
Number
14
Pages
2817-2828
Language
english
Abstract
Cells control the size of their compartments relative to cell volume, but there is also size control within each organelle. Yeast vacuoles neither burst nor do they collapse into a ruffled morphology, indicating that the volume of the organellar envelope is adjusted to the amount of content. It is poorly understood how this adjustment is achieved. We show that the accumulating content of yeast vacuoles activates fusion of other vacuoles, thus increasing the volume-to-surface ratio. Synthesis of the dominant compound stored inside vacuoles, polyphosphate, stimulates binding of the chaperone Sec18/NSF to vacuolar SNAREs, which activates them and triggers fusion. SNAREs can only be activated by lumenal, not cytosolic, polyphosphate (polyP). Control of lumenal polyP over SNARE activation in the cytosol requires the cytosolic cyclin-dependent kinase Pho80-Pho85 and the R-SNARE Nyv1. These results suggest that cells can adapt the volume of vacuoles to their content through feedback from the vacuole lumen to the SNAREs on the cytosolic surface of the organelle.
Keywords
Membrane fusion, Organelle size, Polyphosphate, SNAREs, Vacuole, Lysosome
Pubmed
Web of science
Open Access
Yes
Create date
16/09/2016 10:00
Last modification date
20/08/2019 15:27