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 For a chimpanzee, one good turn deserves another
27.06.2017 | Max-Planck-Institut für Mathematik in den Naturwissenschaften (MPIMIS)

nachricht New method to rapidly map the 'social networks' of proteins
27.06.2017 | Salk Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>