Location: Cereal Crops Improvement Research
Project Number: 3060-22000-051-009-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2023
End Date: Mar 31, 2025
Objective:
1) Use available molecular techniques to characterize the mode of action of SnTox267 and SnTox5
2) Validate and functionally characterize classical effectors (non-NEs) critical or beneficial for the pathogen to complete its pathogenic life cycle.
Approach:
Fungal diseases of cereals cause billions of dollars of annual losses to growers in the form of loss of yield and quality as well as added production costs such as fungicide application. The Parastagonospora nodorum is an economically important pathogen of wheat that causes regular yield losses by the infection of wheat leaves and glumes. The P. nodorum-wheat interaction is a classic example of a necrotrophic interaction where the pathogen targets host pathways that result in disease. Compared to classical biotrophic interactions such as the rusts and powdery mildews, less is known about how necrotrophic pathogens attach their respective hosts. Our research on the P. nodorum-wheat interaction has shown that this pathogen uses multiple necrotrophic effectors (NEs) to target vulnerable susceptibility gene pathways to induce cell death resulting in the release of plant nutrients to the pathogen. However, little is known about the mode of action of these NEs. Additionally, we have almost no understanding of what other effectors are needed for the necrotrophic pathogens to evade the negative effects (oxidative burst, anti-microbials, upregulation of pathogenesis related (PR) proteins) of the host defense response to complete its life cycle. Recent work in our lab has identified several classical effector genes that are potentially involved in evading or manipulating the host defense response. The post-doc on this project will continue the functional characterization of the validated NEs SnTox267 and SnTox5. The functional characterization of these effectors will include the investigation of mode of action of these effectors using techniques including but not limited to heterologous protein expression and protein purification, localization studies using fusion proteins, CRISPR-Cas9 based gene editing, gene transformation, yeast 2-hybrid, and confocal microscopy. Additionally, validation of classical effectors will be accomplished using CRISPR-based gene disruption and editing to validate these genes followed by their functional characterization. Results from this work will give us a better understanding of how this pathogen manipulates its host (wheat) to colonize and reproduce This work will ultimately provide possible options for how to control this and other important necrotrophic diseases.
