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- Mycosphaerella graminicola, the causal agent of wheat Septoria tritici blotch, causes up 40% yield loss. It is the most devastating wheat pathogen in Western Europe (Kema et al. 2002, Genetics 161:1497), with economic losses of at least $400 million dollars (Ponomarenko et al. 2011, Plant Health Instructor.DOI:10.1094). M. graminicola invades and colonises its host plants by hyphal tip growth. In response to infection, the plant innate defence system recognize pathogens and trigger a complex set of physiological responses (Dodds & Rathjen 2010, Nat Rev Genet 11:539; Jones & Dangl, Nature 444:323). It is vital for fungal pathogens to overcome this host immunity very early in the infection process. An important step in the fungal protection is the secretion of a battery of effector proteins Kale & Tyler 2011, Cell Microbiol 13:1839; Rafiqi et al., 2012, Curr Opin Plant Biol 15:477), which suppress plant immunity, thereby allowing rapid fungal colonization of the host. Our most recent research in the plant pathogen Ustilago maydis has shown that expression and secretion of all three effector genes and proteins, respectively, depends on long-range early endosome-based signalling (Bielska et al. 2014, Nat. Commun., 5:5097). This pathway is novel and entirely unknown in fungal host-pathogen interaction. This project aims to analyse a role of early endosomes in effector secretion in M. graminicola. We have already visualise early endosome motility in this fungus. In this project, a student will (i) determine the molecular machinery behind this motility, (ii) interfere with this machinery to block early endosome motility, and (iii) investigate the effect of this on virulence and effector secretion during early plant infection. The student will clone three effector genes and express them in motor mutants. The secretion of these effectors will be monitored using confocal microscopy and effector transcription will be measured using real-time PCR. From a technical/educational point, the project includes (i) molecular cloning, (ii) live cell imaging (confocal, laser-based epi-fluorescence), (iii) plant pathogenicity assays, and (iv) real-time PCR. This will be complemented by a 16 week rotation project in the lab of Prof. Sarah Gurr. Here, the student will apply a mathematical modelling approach, interrogating FERA databases, to analyse wheat blotch outbreaks and predict the movement of M. graminicola in the European Union. A similar approach was previously published by Prof. Gurr (Bebber et al. 2014, Global Ecol. Biogeogr., DOI: 10.1111). This theoretical project perfectly complements the lab work of the prospective student.