PhD "Genetics of Rhizobium phaseoli", John Innes Institute, 1980
In 1990 I moved to Wye College and took the opportunity to move into research on the pathology of the then developing model plant Arabidopsis. In an ongoing collaboration with Eric Holub and Ian Crute at HRI I became involved in the cloning of disease resistance genes from Arabidopsis as the first step to understanding of disease resistance mechanisms in plants. To further cement this collaboration I joined HRI in 1997. We have published on the cloning of three such genes, all of which tell unique stories in terms of gene evolution and disease resistance mechanisms. One of these genes, RPP13, shows the greatest variation between alleles of any plant gene cloned to date and we believe it will become a key gene in understanding the evolution of resistance gene structure and function.
In order to progress further, however, it became clear to me that we needed to clone the genes in the pathogen that triggered the resistance response. Hence, together with Eric Holub and Ian Crute, we developed all the necessary tools to study the downy mildew pathogen Hyaloperonospora arabidopsidis (formerly Peronospora parasitic). This was a major achievement as the organism is an oomycete, a little studied group of very serious pathogens, and is an obligate biotroph, meaning that it can only be cultured by growing on its host plant. We succeeded in cloning two pathogenicity effector genes from this pathogen and are in the process of analysing their role in the plant. This groundbreaking work was published in Science and Plant Cell.
Collaborations have always formed an important part of my research. A very important collaboration has been with Paul Birch at the James Hutton Institute (formerly SCRI), which have revealed some fascinating relationships between H. arabidopsidis and Phytopthora infestans (potato blight).
Then came bioinformatics. A collaboaration with Prof. Brett Tyler (VBI, USA) resulted in the sequencing of the H. arabidopsidis genome, which was published in Science in 2010. This wealth of information enabled us to identify a unique motif within effector proteins allowing over 130 putative effectors to be identified. Currently, my group is using the effector proteins as baits to identify their host targets. This is revealing a complex and highly interconnected network of proteins representing the immune interactome.
Since 2008, I have been leading a collaboration with colleagues in Warwick, Exeter and Essex Universities where we are using systems biology approaches to analyse plant stress responses. Using high resolution transcript profiling we are using mathematical techniques to predict networks of genes responding to biotic and abiotic challenges.
Integrating the transcriptional models and protein interaction networks is a key goal of my current research.