Abstract
Previous work has showed that ergosterol and sphingolipids become sorted to secretory vesicles immunoisolated using a chimeric, artificial raft membrane protein as bait. In this study, we have extended this analysis to three populations of secretory vesicles isolated using natural yeast plasma membrane (PM) proteins: Pma1p, Mid2p and Gap1*p as baits. We compared the lipidomes of the immunoisolated vesicles with each other and with the lipidomes of the donor compartment, the trans-Golgi network, and the acceptor compartment, the PM, using a quantitative mass spectrometry approach that provided a complete lipid overview of the yeast late secretory pathway. We could show that vesicles captured with different baits carry the same cargo and have almost identical lipid compositions; being highly enriched in ergosterol and sphingolipids. This finding indicates that lipid raft sorting is a generic feature of vesicles carrying PM cargo and suggests a common lipid-based mechanism for their formation.
© 2011 John Wiley & Sons A/S.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Amino Acid Transport Systems / chemistry
-
Amino Acid Transport Systems / genetics
-
Amino Acid Transport Systems / metabolism
-
Ergosterol / chemistry
-
Ergosterol / metabolism*
-
Intracellular Signaling Peptides and Proteins / chemistry
-
Intracellular Signaling Peptides and Proteins / genetics
-
Intracellular Signaling Peptides and Proteins / metabolism
-
Lipid Metabolism
-
Mass Spectrometry
-
Membrane Glycoproteins / chemistry
-
Membrane Glycoproteins / genetics
-
Membrane Glycoproteins / metabolism
-
Membrane Microdomains / chemistry
-
Membrane Microdomains / metabolism*
-
Membrane Proteins / chemistry
-
Membrane Proteins / genetics
-
Membrane Proteins / metabolism*
-
Proton-Translocating ATPases / chemistry
-
Proton-Translocating ATPases / genetics
-
Proton-Translocating ATPases / metabolism
-
Saccharomyces cerevisiae / cytology
-
Saccharomyces cerevisiae / metabolism*
-
Saccharomyces cerevisiae Proteins / chemistry
-
Saccharomyces cerevisiae Proteins / genetics
-
Saccharomyces cerevisiae Proteins / metabolism
-
Secretory Vesicles / chemistry
-
Secretory Vesicles / metabolism*
-
Sphingolipids / chemistry
-
Sphingolipids / metabolism*
-
trans-Golgi Network / metabolism
Substances
-
Amino Acid Transport Systems
-
GAP1 protein, S cerevisiae
-
Intracellular Signaling Peptides and Proteins
-
MID2 protein, S cerevisiae
-
Membrane Glycoproteins
-
Membrane Proteins
-
Saccharomyces cerevisiae Proteins
-
Sphingolipids
-
PMA1 protein, S cerevisiae
-
Proton-Translocating ATPases
-
Ergosterol