How do plants recognise fungal effector proteins?

Plant pathogens pose major challenges both to crop production and to the resilience of natural ecosystems. Every year, millions of tons of crops are lost to the destructive impact of plant diseases. How we protect plants from their most damaging pathogens is therefore vital to a future of sustainable agriculture and food security. The Kettles laboratory combines molecular biology, protein biochemistry and computational approaches to study what makes fungal and bacterial phytopathogens so adept at causing disease. We investigate how the plant innate immune system functions at the molecular level and how it could be enhanced to prevent infections. One of the model systems we use to understand these processes is the interaction between wheat plants and the hemibiotrophic fungus Zymoseptoria tritici. This pathogen is one of the most significant threats to wheat production globally, and is particularly problematic in the UK and Europe.

About PhD project

Successful pathogens secrete virulence proteins (effectors) during plant colonisation. Effectors are highly diverse, often uncharacterised proteins that function to suppress immunity or disrupt plant cellular function. Our previous work has revealed that there is a highly diverse effector repertoire in the fungus Z. tritici (Kettles et al. 2017, Kettles et al. 2018). Similar to other pathogens, many Z. tritici effectors are highly polymorphic with few putative domains or functions. We have also identified effectors with similarity to broad-spectrum toxins that may be involved in interaction with host plants or other microorganisms in the environment. Despite this work, it is still unknown how most effectors contribute to disease or are differentially recognised during infection of either host (wheat) or non-host plants. This project will investigate the extent to which effector recognition contributes to disease resistance against this pathogen.

This project aims to address three key areas:
(1) to determine the functions of Z. tritici effectors during interactions with both host and non-host plants,
(2) to assess effector diversity and subsequent impact on function across global Z. tritici populations, and
(3) to identify effector recognition and immune signalling components in plants.

This project will feature both wet-lab and computational components. The successful applicant will gain extensive experience of functional genomics, molecular biology, biochemistry, fungal handling and pathoassays, and techniques associated with protein expression and purification. There will be opportunity to perform computational genomic analysis using a global Z. tritici isolate collection to assess effector diversity. The project will also use transcriptomic analysis (RNAseq) to assess plant responses to effector variants.

For any informal enquiries, please contact [Email Address Removed]. Further details on the Kettles lab can he found here (https://www.birmingham.ac.uk/staff/profiles/biosciences/kettles-graeme.aspx). Details on how to apply for this project can be found on the MIBTP website (https://warwick.ac.uk/fac/cross_fac/mibtp/pgstudy/phd_opportunities/plantandcrop2020/combat)