Dataset Information

Analysis of the Candida albicans phosphoproteome

ABSTRACT: Candida albicans is an important human fungal pathogen in both immunocompetent and immunocompromised individuals. In response to environmental stimuli, C. albicans regulates complex phenotypic transitions between morphological states, mating competence, and biofilm formation. In addition, other processes related to virulence, stress resistance, and cell wall structure are also highly regulated. Based on the phenotypes of mutants lacking different kinases, it is clear that protein phosphorylation plays an important role in the regulation of these pathways. Here, we present a qualitative analysis of the phosphoproteome of C. albicans hyphae. We identified 19,590 unique peptides that corresponded to 15,906 unique phosphosites on 2,896 proteins. The ratios of serine, threonine and tyrosine phosphosites were 80.01%, 18.11%, and 1.81%, respectively. The majority of proteins (2,111) contained at least two detected phosphorylation sites. Consistent with findings in other fungi, cytoskeletal proteins were among the most highly phosphorylated proteins, and there were differences in GO terms for proteins with serine and threonine versus tyrosine phosphorylation sites. This large-scale analysis identified phosphosites in protein components of Mediator, an important transcriptional co-regulatory protein complex. In vitro studies revealed Cdk8 (Ssn3), a kinase within the Mediator complex, was sufficient to catalyze a subset of these phosphorylations suggesting the potential for autoregulation. These data represent the deepest single analysis of a fungal phosphoproteome, and will lay the groundwork for future analyses of the C. albicans phosphoproteome and specific phosphoproteins.

INSTRUMENT(S): Orbitrap Fusion, Q Exactive

ORGANISM(S): Candida Albicans (yeast)

SUBMITTER: Arminja Kettenbach

LAB HEAD: Arminja Kettenbach

PROVIDER: PXD001844 | Pride | 2015-03-25

REPOSITORIES: Pride

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Publications

Analysis of the Candida albicans Phosphoproteome.

Willger S D SD Liu Z Z Olarte R A RA Adamo M E ME Stajich J E JE Myers L C LC Kettenbach A N AN Hogan D A DA

Eukaryotic cell 20150306 5

Candida albicans is an important human fungal pathogen in both immunocompetent and immunocompromised individuals. C. albicans regulation has been studied in many contexts, including morphological transitions, mating competence, biofilm formation, stress resistance, and cell wall synthesis. Analysis of kinase- and phosphatase-deficient mutants has made it clear that protein phosphorylation plays an important role in the regulation of these pathways. In this study, to further our understanding of ...[more]

PMID: 25750214

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Dataset Information

Analysis of the Candida albicans phosphoproteome

Publications

Analysis of the Candida albicans Phosphoproteome.

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