Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UNC plant researchers discover proteins interact to form hair-trigger protection against invaders

27.06.2005


Experimenting with Arabidopsis, a fast-growing cousin of the humble mustard plant, scientists at the University of North Carolina at Chapel Hill got a big surprise while investigating how plants respond to attacks from disease organisms such as bacteria and viruses.



"Contrary to what we thought we’d find, our experiments showed that at least three different proteins work in concert with one another in tug-of war or teeter totter-fashion to keep plant defenses in a state of constant readiness," said Dr. Jeffrey L. Dangl, John N. Couch professor of biology in UNC’s College of Arts and Sciences.

Previously, he and others believed that the proteins -- RAR1, SGT1 and HSP90 -- were required for what is called signal transduction -- relaying like Paul Revere the message that an enemy had arrived, Dangl said. Instead, they are needed to form an even earlier disease surveillance antenna or hair trigger. When disease invaders pull that trigger, infected plants cells quickly commit suicide, often preventing the invader from destroying the entire plant.


The new discovery appears to be a universal mechanism for defense by all plants against not only bacteria and viruses, but also parasitic fungi, insects and worms, he said.

"This work is important because every year, these organisms cause us to lose some 30 percent of our grain, fruit and vegetable crops after all the human, water and soil energy has already gone into producing them," Dangl said. "The hope is that we might be able to manipulate plants’ immune systems to make them more resistant to pathogens using fewer expensive and polluting chemicals."

A report on the findings appears in this week’s edition (June 24) of Science Express, the online, early-release version of the journal Science. Other authors are postdoctoral fellow Dr. Ben F. Holt III and Ph.D. student Youssef Belkhadir, both in biology.

"Plants use resistance proteins to defend themselves against pathogen attack by initiating a defense response," Holt said. "The proteins RAR1, HSP90 and SGT1 were previously thought to work together to help resistance proteins in this function. To our surprise, we found that SGT1 can actually work against, or antagonize, the other two proteins to disable resistance protein function."

The researchers also showed why they antagonized each other, he said. RAR1 and HSP90 can prevent resistance proteins from disappearing, while SGT1 helps them disappear. The result is that the system remains poised for an immediate response to bacteria and other attackers.

"By controlling disappearance of resisting proteins, RAR1, HSP90 and SGT1 control whether or not the plant is about to recognize that it is under pathogen attack," Holt said. "So the emerging story is that RAR1 and HSP90 keep resistance proteins ready to perceive pathogen signals, and SGT1 probably pulls against these two to send resistance proteins to their destruction."

The National Science Foundation supported the research through its Arabidopsis 20-10 Project, which aims to describe the functions of all 28,000 genes in the model plant.

Scientists study Arabidopsis, also known as thale cress or mouse-eared cress, because it is small and can produce five to six generations a year rather than just one or two like most crop plants. That rapid reproduction allows them to study the plant’s genetics faster than they could with other species.

Understanding Arabidopsis completely will teach scientists an enormous amount about all other flowering plants, which are closely related genetically, Dangl said. The new genomics technology, developed by Patrick Brown and David Botstein at Stanford University, has been applied to yeast, fruit flies and humans but not to plants in a large, systematic way. Arabidopsis was the first plant for which scientists succeeded in mapping its entire genetic composition.

Dangl is also with UNC’s Curriculum in Genetics, Department of Microbiology and Immunology and Carolina Center for Genome Sciences.

David Williamson | EurekAlert!
Further information:
http://www.unc.edu

More articles from Life Sciences:

nachricht Repairing damaged hearts with self-healing heart cells
22.08.2017 | National University Health System

nachricht Biochemical 'fingerprints' reveal diabetes progression
22.08.2017 | Umea University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>