Palmitoylation determines the function of Vac8 at the yeast vacuole
Abstract
Palmitoylation stably anchors specific proteins to membranes, but may also have a direct effect on the function of a protein. The yeast protein Vac8 is required for efficient vacuole fusion, inheritance and cytosol-to-vacuole trafficking. It is anchored to vacuoles by an N-terminal myristoylation site and three palmitoylation sites, also known as the SH4 domain. Here, we address the role of Vac8 palmitoylation and show that the position and number of substrate cysteines within the SH4 domain determine the vacuole localization of Vac8: stable vacuole binding of Vac8 requires two cysteines within the N-terminus, regardless of the combination. Importantly, our data suggest that palmitoylation adds functionality to Vac8 beyond simple localization. A mutant Vac8 protein, in which the palmitoylation sites were replaced by a stretch of basic residues, still localizes to vacuole membranes and functions in cytosol-to-vacuole transport, but can only complement the function of Vac8 in morphology and inheritance if it also contains a single cysteine within the SH4 domain. Our data suggest that palmitoylation is not a mere hydrophobic anchor required solely for localization, but influences the protein function(s).
Additional Information
Published by The Company of Biologists 2006. Accepted 7 March 2006. First published online 23 May 2006. We thank Daniel Klionsky, Michael Knop, Sean Munro, and Herbert Tschochner for plasmids and antibodies, members of the Ungermann lab for discussions, and Nadine Decker and Gabriela Müller for expert technical assistance. This work was supported by a grant from the DFG (UN111/2-3), the SFB 638, the EMBO Young Investigator program, the Fonds der Chemischen Industrie and by predoctoral fellowships of the Boehringer Ingelheim Fonds (to L.E.P.D., K.S. and H.H.) and the National Science Foundation Graduate Research Fellowship Program (to T.J.L.). Supplementary material available online at http://jcs.biologists.org/cgi/content/full/119/12/2477/DC1.Attached Files
Published - SUBjcs06.pdf
Supplemental Material - SUBjcs06table1.pdf
Supplemental Material - SUBjcs06table2.pdf
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Additional details
- Eprint ID
- 12161
- Resolver ID
- CaltechAUTHORS:SUBjcs06
- UN111/2-3
- Deutsche Forschungsgemeinschaft (DFG)
- 638
- Sonderforschungsbereiche
- European Molecular Biology Organization
- Fonds der Chemischen Industrie
- Boehringer Ingelheim Fonds
- National Science Foundation
- Created
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2008-10-27Created from EPrint's datestamp field
- Updated
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2021-11-08Created from EPrint's last_modified field