Nav: Home

Breakthrough in battle against rice blast

March 26, 2018

Scientists have found a way to stop the spread of rice blast, a fungus that destroys up to 30% of the world's rice crop each year.

An international team led by the University of Exeter showed that chemical genetic inhibition of a single protein in the fungus stops it spreading inside a rice leaf - leaving it trapped within a single plant cell.

The finding is a breakthrough in terms of understanding rice blast, a disease that is hugely important in terms of global food security.

However, the scientists caution that this is a "fundamental" discovery - not a cure that can yet be applied outside the laboratory.

The research revealed how the fungus can manipulate and then squeeze through natural channels (called plasmodesmata) that exist between plant cells.

"This is an exciting breakthrough because we have discovered how the fungus is able to move stealthily between rice cells, evading recognition by the plant immune system," said senior author Professor Nick Talbot FRS, of the University of Exeter.

"It is clearly able to suppress immune responses at pit fields (groups of plasmodesmata), and also regulate its own severe constriction to squeeze itself through such a narrow space.

"And all this is achieved by a single regulatory protein. It's a remarkable feat."

Rice blast threatens global food security, destroying enough rice each year to feed 60 million people.

It spreads within rice plants by invasive hyphae (branching filaments) which break through from cell to cell.

In their bid to understand this process, the researchers used chemical genetics to mutate a signalling protein to make it susceptible to a specific drug.

The protein, PMK1, is responsible for suppressing the rice's immunity and allowing the fungus to squeeze through pit fields - so, by inhibiting it, the researchers were able to trap the fungus within a cell.

This level of precision led the team to discover that just one enzyme, called a MAP kinase, was responsible for regulating the invasive growth of rice blast.

The research team hope this discovery will enable them to identify targets of this enzyme and thereby determine the molecular basis of this devastating disease.

The research was led by Dr Wasin Sakulkoo, who recently received his PhD from Exeter.

Dr Sakulkoo is a Halpin Scholar, a programme initiated by the generosity of Exeter alumni Les and Claire Halpin, which funds students from rice-growing regions of the world to study with Professor Talbot's research group.

Dr Sakulkoo is from Thailand, and has returned home to a new position in industry following graduation.
-end-
The project involved state-of-the-art live cell imaging procedures pioneered at Exeter by postdoctoral fellow Dr George Littlejohn, who is now a lecturer at Plymouth University, and electron microscopy specialists Christian Hacker and Ana Correia.

The research was also an international effort involving collaborators from Kansas State University, Dr Barbara Valent and Dr Ely Oliviera Garcia, and former Marie Curie Fellow Dr Miriam Oses-Ruiz.

The work was funded by the European Research Council (ERC).

Professor Talbot said: "International collaboration is central to our research and vital to keep us operating at the frontiers of understanding.

"Support from the ERC was pivotal to this project, as was the generous support of Claire Halpin, who has continued to support my research work and believe in the power of fundamental research and retraining to solve one of the world's most devastating diseases."

The paper, published in the journal Science, is entitled: "A single fungal MAP kinase controls plant cell-to-cell invasion by the rice blast fungus."

University of Exeter

Related Fungus Articles:

Taming the wild cheese fungus
The flavors of fermented foods are heavily shaped by the fungi that grow on them, but the evolutionary origins of those fungi aren't well understood.
Candida auris is a new drug-resistant fungus emerging globally and in the US early detection is key to controlling spread of deadly drug-resistant fungus
Early identification of Candida auris, a potentially deadly fungus that causes bloodstream and intra-abdominal infections, is the key to controlling its spread.
Genetic blueprint for extraordinary wood-munching fungus
The first time someone took note of Coniochaeta pulveracea was more than two hundred years ago, when the South African-born mycologist Dr Christiaan Hendrik Persoon mentioned it in his 1797 book on the classification of fungi.
How a fungus can cripple the immune system
An international research team led by Professor Oliver Werz of Friedrich Schiller University, Jena, has now discovered how the fungus knocks out the immune defenses, enabling a potentially fatal fungal infection to develop.
North American checklist identifies the fungus among us
Some fungi are smelly and coated in mucus. Others have gills that glow in the dark.
Tropical frogs found to coexist with deadly fungus
In 2004, the frogs of El Copé, Panama, began dying by the thousands.
Deadly amphibian fungus has its origins in East Asia
The fungus kills frogs, toads and salamanders, and now we know where it emerged.
How wheat can root out the take-all fungus
In the soils of the world's cereal fields, a family tussle between related species of fungi is underway for control of the crops' roots, with food security on the line.
Fungus senses gravity using gene borrowed from bacteria
The pin mold fungus Phycomyces blakesleeanus forms a dense forest of vertically growing fruiting bodies, but how does it know which way is 'up'?
Invasion of the body-snatching fungus
UConn researchers recently documented in Nature Scientific Reports a gory and fascinating relationship between periodical cicadas and a fungus that infects them, hijacks their behavior, and causes a scene straight out of a zombie movie.
More Fungus News and Fungus Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab