Targeting how fungi ‘taste’ wheat could be key to developing control

Exploring how a hazardous fungal pathogen ‘tastes’ its surroundings within a wheat plant to coordinate virulence could be the key to developing new control strategies, scientists believe.

Researchers at the University of Bath and Rothamsted Research have been examining how “fungal G-protein coupled receptors”, which are similar to taste receptors on our tongues, are involved in promoting Fusarium Head Blight (FHB) – a damaging and hazardous disease of wheat which is the number one floral disease in cereals globally.

Fusarium Head Blight targets the ear and grain of the wheat plants and is therefore a major problem for farmers of one of the world’s most important crops. The disease is economically costly, damaging wheat crops towards the end of the growing cycle, and contaminating the wheat grain with fungal toxins (mycotoxins) which are dangerous for humans and animals to eat.

In the UK we have outbreaks of FHB every few years, experiencing wheat crop losses of around 10% in 2012. In other parts of the world such as the USA, Brazil and China, the disease causes severe crop losses and mycotoxin contamination problems for farmers every harvest.

Currently there are no truly effective ways to control FHB, which is spread by airborne spores.

The research team, led by fungal biologist Dr Neil Brown from the University of Bath’s Department of Biology & Biochemistry, thinks that G-protein coupled receptors are a promising targets to develop new approaches to control fungal diseases, including the FHB causing pathogen Fusarium graminearum.

These fungal receptors ‘taste’ their environment and signal changes to the fungi cell, kicking off an appropriate biological response, including mating, mycotoxin production and virulence.

In a series of experiments the scientific team demonstrated that F. graminearum’s receptors are important in wheat infection. The team made a collection of fungal mutants lacking individual receptors. They went on to show that the absence of one type of receptor, specific to fungi, allowed the wheat plant to mount a stronger defence, which causes a traffic jam of invading filamentous fungal structures called hyphae and reducing the progression of infection.

The team also showed that the removal of this receptor meant that the virulence on wheat was reduced, because various fungal processes required for infection were disrupted and dysregulated.

The research is published in PLOS Pathogens.

Dr Brown said: “Fusarium Head Blight is the number one floral disease of cereals worldwide.

“G-protein coupled receptors have been studied extensively in humans, where around 40% of our pharmaceuticals target these human receptors, as they’re exposed on the cell surface, making them accessible to drugs, and they control important biological functions. Fungi have their own G-protein coupled receptors, but we know very little about them.

“Our results show that fungal receptors are important for Fusarium infection of wheat. By learning more about the structure and function of these fungal-specific receptors, and the compounds they detect, we may be able to develop new approaches to control FHB and other plant pathogens.”

Professor Kim Hammond-Kosack said: “The options to control Fusarium floral infections in cereal crops are very limited at the moment. This is causing growers and processors in the food and feed industries a tremendous headache, and why Rothamsted has been looking to apply our considerable expertise in crop diseases to this problem. These results open up the possibility of devising novel ways to control FHB disease through either targeted drug development or by eliminating the signals these receptors perceive during a fungal attack.”

The research was funded by the Biotechnology and Biological Sciences Research Council through its Future Leaders Fellowship Programme awarded to Dr Neil Brown.

“Non-canonical fungal G-protein coupled receptors promote Fusarium head blight on wheat” is published in PLOS Pathogens and is available as an open access paper.

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For further information, please contact Chris Melvin in the University of Bath Press Office on +44 (0)1225 383 941 or [email protected]

Notes

University of Bath

The University of Bath is one of the UK’s leading universities both in terms of research and our reputation for excellence in teaching, learning and graduate prospects.

The University is rated Gold in the Teaching Excellence Framework (TEF), the Government’s assessment of teaching quality in universities, meaning its teaching is of the highest quality in the UK.

In the Research Excellence Framework (REF) 2014 research assessment 87 per cent of our research was defined as ‘world-leading’ or ‘internationally excellent’. From developing fuel efficient cars of the future, to identifying infectious diseases more quickly, or working to improve the lives of female farmers in West Africa, research from Bath is making a difference around the world. Find out more: http://www.bath.ac.uk/research/

Well established as a nurturing environment for enterprising minds, Bath is ranked highly in all national league tables. We are ranked 6th in the UK by The Guardian University Guide 2019, 5th for graduate employment in The Times & Sunday Times Good University Guide 2019, and 4th in the Times Higher Education Student Experience Survey 2018.

About Rothamsted Research

Rothamsted Research is the longest-running agricultural research institute in the world. We work from gene to field with a proud history of ground-breaking discoveries, from crop treatment to crop protection, from statistical interpretation to soils management. Our founders, in 1843, were the pioneers of modern agriculture, and we are known for our imaginative science and our collaborative influence on fresh thinking and farming practices.

Through independent science and innovation, we make significant contributions to improving agri-food systems in the UK and internationally. In terms of the institute’s economic contribution, the cumulative impact of our work in the UK was calculated to exceed £3000 million a year in 2015. Our strength lies in our systems approach, which combines science and strategic research, interdisciplinary teams and partnerships.

Rothamsted is also home to three unique resources. These National Capabilities are open to researchers from all over the world: The Long-Term Experiments, Rothamsted Insect Survey and the North Wyke Farm Platform.

We are strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC), with additional support from other national and international funding streams, and from industry. We are also supported by the Lawes Agricultural Trust (LAT).

For more information, visit https://www.rothamsted.ac.uk/; Twitter @Rothamsted

1Rothamsted Research and the Value of Excellence: A synthesis of the available evidence, by Séan Rickard (Oct 2015)

About BBSRC

The Biotechnology and Biological Sciences Research Council is part of UK Research and Innovation, a non-departmental public body funded by a grant-in-aid from the UK government.

BBSRC invests in world-class bioscience research and training on behalf of the UK public. Our aim is to further scientific knowledge, to promote economic growth, wealth and job creation and to improve quality of life in the UK and beyond.

Funded by government, BBSRC invested £469 million in world-class bioscience in 2016-17. We support research and training in universities and strategically funded institutes. BBSRC research and the people we fund are helping society to meet major challenges, including food security, green energy and healthier, longer lives. Our investments underpin important UK economic sectors, such as farming, food, industrial biotechnology and pharmaceuticals.

More information about BBSRC, our science and our impact.

More information about BBSRC strategically funded institutes

About LAT

The Lawes Agricultural Trust, established in 1889 by Sir John Bennet Lawes, supports Rothamsted Research’s national and international agricultural science through the provision of land, facilities and funding. LAT, a charitable trust, owns the estates at Harpenden and Broom’s Barn, including many of the buildings used by Rothamsted Research. LAT provides an annual research grant to the Director, accommodation for nearly 200 people, and support for fellowships for young scientists from developing countries. LAT also makes capital grants to help modernise facilities at Rothamsted, or invests in new buildings.