| This project going to be… | Experimental (lab/field based) |
| Email | mark.banfield@jic.ac.uk |
| Position held | Group Leader |
| Title of Project | Exploring effector perception by a novel NLR immune receptor to engineer resistance to wheat blast and other crop diseases |
| Institution Department and Address | Dept. of Biochemistry & Metabolism, John Innes Centre, Norwich Research Park, Colney Lane, |
| Norwich, Norfolk NR4 7UH |
| United Kingdom |
| Full Name of Supervisor | Mark J Banfield |
| Date of Project Commencement | 26/06/2023 |
| Duration (weeks) | 10 |
| Brief Description of Project | Magnaporthe oryzae is the agent of blast disease, which causes significant losses to cereal crop yields world-wide. While rice is the best-known host of this pathogen, wheat blast disease is emerging as a major threat to cultivation of this crop around the world. To promote infection, M. oryzae delivers virulence proteins (effectors) into plant cells to remodel host processes. To defend themselves from disease, plants have evolved intracellular NLR immune receptors to detect effector proteins directly or indirectly detect their activities. Upon effector perception, NLR activation results in initiation of plant defences, which culminate in a form of programmed cell death that isolates the pathogen and prevents further spread throughout the plant. Recently, our collaborator Professor Ryohei Terauchi at the IBRC in Iwate, Japan, has identified an NLR, Pi-eTO-36, that provides resistance to isolates of M. oryzae carrying the newly characterised wheat blast effectors eTO-20 and eTO-36. We determined the crystal structures of eTO-20 and eTO-36 and revealed these effectors adopt a protein fold previously unobserved (experimentally) for M. oryzae, but shared in diverse plant pathogens. Importantly, prior to the cloning of Pi-eTO-36, there has not been an NLR reported that recognises eTO-20/eTO-36 type effectors, despite their wide distribution. We have shown that the Pi-eTO-36 NLR recognition of eTO-20/eTO-36 can be recapitulated in the model plant Nicotiana benthamiana. Surprisingly, Pi-eTO-36 is not only capable of recognising eTO-20 and eTO-36 in N. benthamiana, but can also recognise an effector from Colletotrichum that is predicted to share the same fold. As eTO-20/eTO-36 type effectors are found in diverse pathogenic fungi, this raises the possibility that Pi-eTO-36 could be a broad spectrum NLR capable of providing resistance to a range of important crop diseases. This research project aims to characterise the extent of the effector recognition profile of Pi-eTO-36 by challenging this NLR with effectors from several fungal phytopathogens, including M. oryzae, Fusarium oxysporum, Verticillium dahlia, Blumeria graminis f.sp. hordei and Cadophora malorum. The student will clone the effectors into suitable expression vectors and perform cell death and co-immunoprecipitation assays in N. benthamiana via agrobacterium-mediated transient expression. They will also attempt to map the region of the NLR to which the effectors bind, if direct interaction is confirmed. In addition to the plant assays, the student will be trained in techniques to produce and purify proteins and perform biochemical and structural studies to investigate protein function. The project will provide diverse training opportunities in a stimulating intellectual environment and within the emerging area of molecular engineering plant pathogen interactions for new resistance profiles. |
| Attach the recommended reading for the project | Jizong Wang, Wen Song, Jijie Chai (2023) Structure, biochemical function, and signaling mechanism of plant NLRs. Molecular Plant 16: 75-95 |
| Bentham AR, De la Concepcion JC, Mukhi N, Zdrzałek R, Draeger M, Gorenkin D, Hughes RK & Banfield MJ (2020) A molecular roadmap to the plant immune system. Journal of Biological Chemistry 295: 14916-35. |
| Maidment JH, Shimizu M, Sham V, Franceschetti M, Longya A, Stevenson CEM, De la Concepcion JC, Białas A, Kamoun S, Terauchi R & Banfield MJ (2022) Effector target-guided engineering of an integrated domain expands the disease resistance profile of a rice NLR immune receptor. bioRxiv: https://doi.org/10.1101/2022.06.14.496076. |
| Islam, M.T., Gupta, D.R., Hossain, A. et al. Wheat blast: a new threat to food security. Phytopathol Res 2, 28 (2020). |
