Poster Presentation 25th Annual Lorne Proteomics Symposium 2020

Towards the generation of a comprehensive proteome map for Phytophthora cinnamomi, the causal agent of native dieback (#91)

Christina Andronis 1 , Tammy Casey 2 , Giles Hardy 3 , James Hane 1 , Richard Oliver 1 , Richard Lipscombe 2 , Kar-Chun Tan 1
  1. Curtin University, Perth, WA, Australia
  2. Proteomics International, Perth, WA, Australia
  3. Centre for phytophthora Science and Management, Murdoch University, Perth, WA, Australia

Phytophthora cinnamomi is a pathogenic oomycete that poses a significant threat to global biodiversity. It causes loss of vegetation/ crops and tree death by attaching to the fine-feeder roots and releasing apoplastic and cytosolic effectors. The destructive nature of these effectors during plant-pathogen interactions drives a complex array of defence responses and when successful, the pathogen can cause plant death. Phytophthora cinnamomi exhibits various life stages, which enable it to survive through harsh environments. This has contributed to its success as a pathogen as it takes advantage of weakened potential hosts

However, the molecular mechanism of P. cinnamomi pathogenicity is not well-understood. In order to better understand the pathogen, a proteomic approach was used to dissect sub-cellular proteomes of P. cinnamomi. We were able to extract high quality intracellular, secreted, zoospore and membrane proteomes of P. cinnamomi and perform analysis using gel-free label-free shotgun proteomics in addition to iTRAQ. We predicted functional annotations using gene ontologies for deferentially-abundant proteins, with a view to understand pathogen proteins production during host infection. A proteomic pipeline was also applied to non-quantitative data to identify gene models that were not predicted using traditional methods. This provided us with a second set of draft gene models that were subsequently defined via predicted gene ontology terms. This data is working toward a comprehensive reference proteome for the pathogen.