Phosphatidylinositol 4,5-bisphosphate regulates two steps of homotypic vacuole fusion.

Détails

ID Serval
serval:BIB_0E5712005183
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Phosphatidylinositol 4,5-bisphosphate regulates two steps of homotypic vacuole fusion.
Périodique
Molecular Biology of the Cell
Auteur(s)
Mayer A., Scheglmann D., Dove S., Glatz A., Wickner W., Haas A.
ISSN
1059-1524 (Print)
ISSN-L
1059-1524
Statut éditorial
Publié
Date de publication
2000
Peer-reviewed
Oui
Volume
11
Numéro
3
Pages
807-817
Langue
anglais
Résumé
Yeast vacuoles undergo cycles of fragmentation and fusion as part of their transmission to the daughter cell and in response to changes of nutrients and the environment. Vacuole fusion can be reconstituted in a cell free system. We now show that the vacuoles synthesize phosphoinositides during in vitro fusion. Of these phosphoinositides, phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate (PI(4,5)P(2)) are important for fusion. Monoclonal antibodies to PI(4,5)P(2), neomycin (a phosphoinositide ligand), and phosphatidylinositol-specific phospholipase C interfere with the reaction. Readdition of PI(4, 5)P(2) restores fusion in each case. Phosphatidylinositol 3-phosphate and PI(3,5)P(2) synthesis are not required. PI(4,5)P(2) is necessary for priming, i.e., for the Sec18p (NSF)-driven release of Sec17p (alpha-SNAP), which activates the vacuoles for subsequent tethering and docking. Therefore, it represents the kinetically earliest requirement identified for vacuole fusion so far. Furthermore, PI(4,5)P(2) is required at a step that can only occur after docking but before the BAPTA sensitive step in the latest stage of the reaction. We hence propose that PI(4,5)P(2) controls two steps of vacuole fusion.
Mots-clé
Membrane Fusion, Phosphatidylinositol 4,5-Diphosphate/physiology, Phosphatidylinositols/physiology, Saccharomyces cerevisiae/physiology, Vacuoles/physiology
Pubmed
Web of science
Création de la notice
24/01/2008 16:06
Dernière modification de la notice
20/08/2019 13:35
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