Assortment of Phosphatidylinositol 3-Kinase Complexes—Atg14p Directs Association of Complex I to the Pre-autophagosomal Structure inSaccharomyces cerevisiae
Open Access
- 1 April 2006
- journal article
- Published by American Society for Cell Biology (ASCB) in Molecular Biology of the Cell
- Vol. 17 (4), 1527-1539
- https://doi.org/10.1091/mbc.e05-09-0841
Abstract
In the yeast Saccharomyces cerevisiae, two similar phosphatidylinositol 3-kinase complexes (complexes I and II) function in distinct biological processes, complex I in autophagy and complex II in the vacuolar protein sorting via endosomes. Atg14p is only integrated into complex I, likely facilitating the function of complex I in autophagy. Deletion analysis of Atg14p revealed that N-terminal region containing the coiled-coil structures was essential and sufficient for autophagy. Atg14p localized to pre-autophagosomal structure (PAS) and vacuolar membranes, whereas Vps38p, a component specific to complex II, localized to endosomes and vacuolar membranes. Vps34p and Vps30p, components shared by the two complexes, localized to the PAS, vacuolar membranes, and several punctate structures that included endosomes. The localization of these components to the PAS was Atg14p dependent but not dependent on Vps38p. Conversely, localization of these proteins to endosomes required Vps38p but not Atg14p. Vps15p, regulatory subunit of the Vps34p complexes, localized to the PAS, vacuolar membranes, and punctate structures independent of both Atg14p and Vps38p. Together, these results indicate that complexes I and II function in distinct biological processes by localizing to specific compartments in a manner mediated by specific components of each complex, Atg14p and Vps38p, respectively.Keywords
This publication has 43 references indexed in Scilit:
- Global analysis of protein localization in budding yeastNature, 2003
- Yeast autophagosomes: de novo formation of a membrane structureTrends in Cell Biology, 2002
- Dissection of Autophagosome Formation Using Apg5-Deficient Mouse Embryonic Stem CellsThe Journal of cell biology, 2001
- Retrograde Traffic Out of the Yeast Vacuole to the TGN Occurs via the Prevacuolar/Endosomal CompartmentThe Journal of cell biology, 1998
- Tor, a Phosphatidylinositol Kinase Homologue, Controls Autophagy in YeastPublished by Elsevier BV ,1998
- Wortmannin causes mistargeting of procathepsin D. evidence for the involvement of a phosphatidylinositol 3-kinase in vesicular transport to lysosomes.The Journal of cell biology, 1995
- Role for phosphatidylinositol 3-kinase in the sorting and transport of newly synthesized lysosomal enzymes in mammalian cells.The Journal of cell biology, 1995
- Novel System for Monitoring Autophagy in the Yeast Saccharomyces cerevisiaeBiochemical and Biophysical Research Communications, 1995
- Isolation of autophagocytosis mutants of Saccharomyces cerevisiaeFEBS Letters, 1994
- Isolation and characterization of autophagy‐defective mutants of Saccharomyces cerevisiaeFEBS Letters, 1993