Protecting plants from stealthy diseases

Protecting plants from stealthy diseases
A team of international scientists led by Michigan State University's Sheng Yang He is helping plants counter attacks by boosting plants' alert system. Credit: Gary Malerba AP and HHMI

Stealthy diseases sometimes trick plants by hijacking their defense signaling system, which issues an alarm that diverts plant resources for the wrong attack and allows the enemy pathogens to easily overrun plants.

A team of international scientists led by Michigan State University, however, is helping counter these attacks by boosting plants' alert system. New research in the current issue of Proceedings of the National Academy of Sciences shows that the team has engineered the receptor for jasmonate, a plant hormone that plays a central role in plant defense, to fend off such stealthy attacks from highly evolved .

"This is the first example of using receptor engineering to fix a disease-vulnerable component of the plant immune system that is frequently hijacked by highly evolved pathogens to cause disease," said Sheng Yang He, an MSU Distinguished Professor in the MSU-Department of Energy Plant Research Laboratory. "This new strategy is different from conventional resistance gene-based crop breeding and is based on a deep understanding of a key component, the jasmonate receptor, of the plant immune system."

This study may have significant practical implications and may serve as an example of finding and fixing disease-vulnerable components of the plant immune system. It also may provide a general strategy of producing a new generation of disease-resistant crop plants against many plant diseases, which collectively cause crop losses of more than $200 billion annually worldwide, added He, a Howard Hughes Medical Institute-Gordon and Betty Moore Foundation Plant Biology Investigator.

Jasmonate regulates plant defenses against a wide variety of pathogens and insects. In an evolutionary arms race between plants and pathogens, however, a group of highly evolved pathogens produce a jasmonate-mimicking toxin, coronatine. The wily bacteria use this toxin to override the jasmonate receptor, which divert plant resources to allow these pathogens to waltz through the security door without tripping any alarms.

To stem this hijacking, He and his team created an enhanced receptor, one that can still signal for insect defense but also has a greatly reduced sensitivity to coronatine toxin. The team's proof-of-concept demonstration shows that the coronatine-based takeover of the jasmonate receptor by bacterial pathogens can be stopped and that plants can be engineered to be resistant to both insects and pathogens, which has been one of the elusive goals of plant pathology/entomology research.

"It took many years of fundamental research by a number of laboratories, but we made a precise repair of the jasmonate decoding system so that it can now distinguish between endogenous jasmonate in plants and bacterial toxin coronatine," He said. "We show that modified Arabidopsis plants equipped with the repaired jasmonate decoding system not only protects against insects, but it also does not allow bacteria to cause disease."

The concept of repairing plant defense system components is appealing and could become a new trend in future efforts to protect plants from numerous plant diseases.


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More information: Host target modification as a strategy to counter pathogen hijacking of the jasmonate hormone receptor, Proceedings of the National Academy of Sciences, www.pnas.org/cgi/doi/10.1073/pnas.1510745112
Citation: Protecting plants from stealthy diseases (2015, November 2) retrieved 20 September 2019 from https://phys.org/news/2015-11-stealthy-diseases.html
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JVK
Nov 02, 2015
Journal article excerpt: "Our results provide a proof-of-concept demonstration that host target modification can be a promising new approach to prevent the virulence action of highly evolved pathogens."

The idea that pathogens evolve should be dismissed in the context of what is currently known about the biophysically constrained chemistry of RNA-mediated protein folding that links ecological variation to ecological adaptation via nutrient-dependent amino acid substitutions that protect organized genomes from virus-driven pathology.

Hosts adapt. Pathogens force hosts to adapt to the theft of nutrient energy that is required for proper protein folding during thermodynamic cycles of protein biosynthesis and degradation that link organism-level thermoregulation to supercoiled DNA, which protects organized genomes from virus-driven genomic entropy.

Nov 02, 2015
"The idea that pathogens evolve should be dismissed because I'm a young earth creationist crank"

There, I fix it for you.

JVK
Nov 02, 2015
Re:
...a young earth creationist crank


If you are going to claim that pathogens or that anything else evolves you will need to explain how the bacterial flagellum re-evolved over-the-weekend.

See: Evolutionary resurrection of flagellar motility via rewiring of the nitrogen regulation system reported as: http://www.the-sc...ewiring/ with my comments to The Scientist on Lenski's ridiculous misrepresentations of how ecological variation leads to ecological adaptations in species from microbes to humans.

Nov 02, 2015
"The route to rewiring – technical background"
https://rewiredfl...ess.com/

A clear and concise explanation, something JVK is incapable of writing.

JVK
Nov 02, 2015
Excerpt: "...in the face of catastrophic mutation threatening bacterial extinction, there is still the capacity for innovative changes to rescue the mutants and save the day."

Nutrient-dependent RNA-mediated amino acid substitutions saved the day in the context of the physiology of pheromone-controlled reproduction.

Nothing "re-evolved." The bacterial flagellum is a required ecological adaptation not a functional structure that mutated its way to existence.

Nov 02, 2015
Another comprehension fail by JVK.

JVK
Nov 03, 2015
Who is this anonymous "Vietvet" (aka Steven Taylor) who claims to be able to tell you what I comprehend about cell type differentiation in the context of an atoms to ecosystems model of nutrient-dependent protection against virus-driven genomic entropy?

Why don't anonymous fools ever tell others what they think they comprehend?

See for example: http://nar.oxford...761.long "Understanding the structure and thermodynamics of base–base interactions provides a foundation for elucidating RNA structure/function relationships, engineering novel applications such as RNA-based therapeutics and addressing questions related to the origins of life (6)."

See also: Nutrient-dependent pheromone-controlled ecological adaptations: from atoms to ecosystems http://figshare.c...s/994281

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