Curtin University researchers have used Artificial Intelligence to explain how fungal pathogens such as those that cause grey mould and sclerotinia stem rot can continuously and successfully infect plants.
Published in Nature Communications, researchers from Curtin’s Centre for Crop and Disease Management and the Université de Toulouse, France, have studied the structures of effectors – which are proteins secreted by fungal pathogens that cause disease on their plant hosts – uncovering important evolutionary information.
Dr Mark Derbyshire, who led the CCDM component of the collaboration, said thanks to AI technology, their study allowed them to understand protein structures at the whole genome scale. Before now, studies on effectors were largely restricted to protein sequences.
“Effectors are hard to find, but when we do find them, they can allow us to find the corresponding gene within the plant species. This information helps with breeding and disease monitoring in the field, which provide agricultural industries with better disease management,” he said.
“Traditionally we would search for effectors by looking at the genome sequence of a pathogen, which often leads to low success. Thanks to this new capability of looking at protein structures at scale, we can better pinpoint where effectors are and speed up the development of better disease management options for growers.”
Dr Derbyshire said the key finding was establishing that pathogens with high genetic diversity between one another can still have similar protein structures, and that these structures likely share common ancestors despite their diversity.
He said with further evolutionary analysis of the protein structures, the study showed that many changes at the protein’s surface affect thermodynamic stability, which could be important for binding to different host proteins.
“What this means is that we’re now at the point of explaining why effectors have such diverse sequences but similar structures,” he said.
“As plants and pathogens are always in an arms race to try and overcome each other’s defence and attack systems, pathogens are continuously evolving to find new ways to attack the plant, and changes in thermodynamic stability at the protein’s surface may be one way of doing this.”
CCDM Director Professor Mark Gibberd said this discovery is another example of CCDM contributing to global scientific knowledge in one of the highest impact journals, yet still continuing to find on-farm solutions to crop disease.
“Not only did Dr Derbyshire and his research team discover a major finding that answers big questions about the way pathogens evolve, but they also continue to find ways to improve profitability for Australian growers,” Professor Gibberd said.
“This is the beauty of our research centre, where we are structured in a way to allow high impact, blue sky science discoveries, yet still make a difference to a grower’s farming business.”
The paper, “Surface frustration re-patterning underlies the structural landscape and evolvability of fungal orphan candidate effectors” can be found here.
CCDM is a national research centre co-supported by Curtin University and the Grains Research and Development Corporation.