Proteomic analysis of phytophthora infestans reveals the importance of cell wall proteins in pathogenicity

Research output: Contribution to journalArticle

Abstract

The oomycete Phytophthora infestans is the most harmful pathogen of potato. It causes the disease late blight, which generates increased yearly costs of up to one billion euro in the EU alone and is difficult to control. We have performed a large-scale quantitative proteomics study of six P. infestans life stages with the aim to identify proteins that change in abundance during development, with a focus on preinfectious life stages. Over 10 000 peptides from 2061 proteins were analyzed. We identified several abundance profiles of proteins that were up- or downregulated in different combinations of life stages. One of these profiles contained 59 proteins that were more abundant in germinated cysts and appressoria. A large majority of these proteins were not previously recognized as being appressorial proteins or involved in the infection process. Among those are proteins with putative roles in transport, amino acid metabolism, pathogenicity (including one RXLR effector) and cell wall structure modification. We analyzed the expression of the genes encoding nine of these proteins using RT-qPCR and found an increase in transcript levels during disease progression, in agreement with the hypothesis that these proteins are important in early infection. Among the nine proteins was a group involved in cell wall structure modification and adhesion, including three closely related, uncharacterized proteins encoded by PITG-01131, PITG-01132, and PITG-16135, here denoted Piacwp1-3. Transient silencing of these genes resulted in reduced severity of infection, indicating that these proteins are important for pathogenicity. Our results contribute to further insight into P. infestans biology, and indicate processes that might be relevant for the pathogen while preparing for host cell penetration and during infection. The mass spectrometry data have been deposited to ProteomeXchange via the PRIDE partner repository with the data set identifier PXD002446.

Details

Authors
  • Svante Resjö
  • Maja Brus
  • Ashfaq Ali
  • Harold J. G. Meijer
  • Marianne Sandin
  • Francine Govers
  • Fredrik Levander
  • Laura J. Grenville-Briggs
  • Erik Andreasson
Organisations
External organisations
  • Swedish University of Agricultural Sciences
  • Wageningen University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biochemistry and Molecular Biology
  • Microbiology
Original languageEnglish
Pages (from-to)1958-1971
Number of pages14
JournalMolecular and Cellular Proteomics
Volume16
Issue number11
Publication statusPublished - 2017 Nov 1
Publication categoryResearch
Peer-reviewedYes