Global analysis of protein palmitoylation in yeast.
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ABSTRACT:
SUBMITTER: Roth AF
PROVIDER: S-EPMC2246083 | biostudies-literature | 2006 Jun
REPOSITORIES: biostudies-literature
Publications
Global analysis of protein palmitoylation in yeast.
Roth Amy F AF Wan Junmei J Bailey Aaron O AO Sun Beimeng B Kuchar Jason A JA Green William N WN Phinney Brett S BS Yates John R JR Davis Nicholas G NG
Cell 20060601 5
Protein palmitoylation is a reversible lipid modification that regulates membrane tethering for key proteins in cell signaling, cancer, neuronal transmission, and membrane trafficking. Palmitoylation has proven to be a difficult study: Specifying consensuses for predicting palmitoylation remain unavailable, and first-example palmitoylation enzymes--i.e., protein acyltransferases (PATs)--were identified only recently. Here, we use a new proteomic methodology that purifies and identifies palmitoyl ...[more]
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Project description:BackgroundPalmitoylation is a reversible post-translational protein modification which involves the addition of palmitate to cysteine residues. Palmitoylation is catalysed by the DHHC family of palmitoyl-acyl transferases (PATs) and reversibility is conferred by palmitoyl-protein thioesterases (PPTs). Mutations in genes encoding both classes of enzymes are associated with human diseases, notably neurological disorders, underlining their importance. Despite the pivotal role of yeast studies in discovering PATs, palmitoylation has not been studied in the key animal model Caenorhabditis elegans.ResultsAnalysis of the C. elegans genome identified fifteen PATs, using the DHHC cysteine-rich domain, and two PPTs, by homology. The twelve uncategorised PATs were officially named using a dhhc-x system. Genomic data on these palmitoylation enzymes and those in yeast, Drosophila and humans was collated and analysed to predict properties and relationships in C. elegans. All available C. elegans strains containing a mutation in a palmitoylation enzyme were analysed and a complete library of RNA interference (RNAi) feeding plasmids against PAT or PPT genes was generated. To test for possible redundancy, double RNAi was performed against selected closely related PATs and both PPTs. Animals were screened for phenotypes including size, longevity and sensory and motor neuronal functions. Although some significant differences were observed with individual mutants or RNAi treatment, in general there was little impact on these phenotypes, suggesting that genetic buffering exists within the palmitoylation network in worms.ConclusionsThis study reports the first characterisation of palmitoylation in C. elegans using both in silico and in vivo approaches, and opens up this key model organism for further detailed study of palmitoylation in future.
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