We are currently advertising DTP and CASE studentships for October 2019 start. The deadline for applications is the 26th November 2018.

27 / 09 / 2018

Natural selection in action: molecular evolution of fungicide resistance (BROWN_J19DTP)

how to apply

Evolution of resistance to drugs and pesticides is a problem of great practical importance but is also one of the clearest demonstrations of natural selection in action. In this project, the student will investigate the evolution of fungal resistance to morpholine fungicides as a model for fitness costs of resistance. The morpholines are a small but important group of fungicides used in agriculture and medicine, and target two proteins in the sterol biosynthesis pathway, ERG24 and ERG2.

Although some crop pathogens have moderate resistance to morpholines, there has been no known outbreak of complete resistance in commercial farming. This is a striking contrast to experience with other fungicides. It suggests that resistance to morpholines involves a fitness penalty and that stronger resistance incurs a higher cost.

The student will test this hypothesis by studying the effect of mutations in ERG24 and ERG2 on responses to morpholines. This will first involve identifying sequence variation associated with morpholine resistance in crop pathogens. The function of these mutations will then be tested in yeast as a model organism, using a range of CRISPR/Cas9 protocols for site-directed mutagenesis. The work will include assessment of the effects of mutations on fungicide resistance, the target protein and fungal fitness in yeast.

The project will give a student outstanding training and research experience in molecular genetics, plant pathology and evolution.