The V-ATPase proteolipid cylinder promotes the lipid-mixing stage of SNARE-dependent fusion of yeast vacuoles.

Details

Serval ID
serval:BIB_DBB56E1E865C
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
The V-ATPase proteolipid cylinder promotes the lipid-mixing stage of SNARE-dependent fusion of yeast vacuoles.
Journal
EMBO Journal
Author(s)
Strasser B., Iwaszkiewicz J., Michielin O., Mayer A.
ISSN
1460-2075 (Electronic)
ISSN-L
0261-4189
Publication state
Published
Issued date
2011
Volume
30
Number
20
Pages
4126-4141
Language
english
Abstract
The V-ATPase V(0) sector associates with the peripheral V(1) sector to form a proton pump. V(0) alone has an additional function, facilitating membrane fusion in the endocytic and late exocytic pathways. V(0) contains a hexameric proteolipid cylinder, which might support fusion as proposed in proteinaceous pore models. To test this, we randomly mutagenized proteolipids. We recovered alleles that preserve proton translocation, normal SNARE activation and trans-SNARE pairing but that impair lipid and content mixing. Critical residues were found in all subunits of the proteolipid ring. They concentrate within the bilayer, close to the ring subunit interfaces. The fusion-impairing proteolipid substitutions stabilize the interaction of V(0) with V(1). Deletion of the vacuolar v-SNARE Nyv1 has the same effect, suggesting that both types of mutations similarly alter the conformation of V(0). Also covalent linkage of subunits in the proteolipid cylinder blocks vacuole fusion. We propose that a SNARE-dependent conformational change in V(0) proteolipids might stimulate fusion by creating a hydrophobic crevice that promotes lipid reorientation and formation of a lipidic fusion pore.
Keywords
Lipid Metabolism, Membrane Fusion, Proteolipids/metabolism, SNARE Proteins/metabolism, Saccharomyces cerevisiae/metabolism, Saccharomyces cerevisiae Proteins/metabolism, Vacuolar Proton-Translocating ATPases/metabolism, Vacuoles/metabolism
Pubmed
Web of science
Open Access
Yes
Create date
25/10/2011 8:31
Last modification date
20/08/2019 16:00
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