Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Critical early-defense trigger in plants found

16.05.2003


The gene for an enzyme that is key to natural disease resistance in plants has been discovered by biologists at the Boyce Thompson Institute for Plant Research (BTI) and at Cornell University. The researchers say that by enhancing the activity of the enzyme they might be able to boost natural disease resistance in crop plants without resorting to pesticides or the introduction of non-plant genes.

The research, reported in the latest (May 16) issue of the journal Cell , describes the discovery of the gene that codes for an enzyme (a protein that carries out a chemical reaction) that is activated when a plant senses it is being attacked by a pathogen. When activated, the enzyme produces nitric oxide (NO), a hormone that tells the plant to turn on its defense arsenal.

According to plant pathologist Daniel F. Klessig, lead author of the Cell paper and president of BTI, located on the Cornell campus, the discovery provides a new understanding of the biochemical and genetic pathways in plants that enable them to protect themselves from disease.



"It’s known that the hormone nitric oxide plays an important role in immunity in plants as well as in humans and other animals," says Klessig. "But the enzyme responsible for its production in plants was unknown until now. With this discovery, we may be able to modify plants so that they produce nitric oxide more quickly, or in larger amounts, when they are attacked by a disease-causing pathogen, enabling them to better protect themselves from invaders."

Authors of the Cell paper, "The Pathogen-Inducible Nitric Oxide Synthase (iNOS) in Plants is a Variant of the P Protein of the Glycine Decarboxylase Complex," also include Meena Chandok, a BTI senior research associate; Anders Jimmy Ytterberg, Cornell doctoral candidate in plant biology; and Klaas J. van Wijk, Cornell assistant professor of plant biology.

"This discovery really is a surprise because the plant enzyme looks very different from mammalian nitric oxide-synthesizing enzymes,"said Brian Crane, Cornell assistant professor of chemistry and chemical biology. Crane now is working with Klessig and Chandok to determine the three-dimensional structure of the protein that will lead biologists to understand its chemical mechanism.

The discovery is significant, the researchers note, because NO is a critical early-warning signal to the plant that it needs to activate its immune response. The difficulty inherent in the research, according to Klessig, was that the plant’s NO-producing enzyme has a completely different sequence than enzymes with similar activity found in all animals. The new research suggests, he says, that the chemistry the plant and animal enzymes use to produce NO also is different.

These differences, Klessig says, could provide clues concerning the way the animal enzyme works, which, in turn, could lead to improved treatment of human diseases by enhancing the activity of the enzyme.

"Part of the success of the green revolution depends on the use of chemical-based fungicides and other pesticides to protect crops against microbial pathogens and insects," says Klessig. "An alternative strategy to protect crops utilizes a plant’s own natural defenses. An approach in which plant molecular biologists have overproduced plant proteins with antimicrobial activity, such as PR proteins or defensin, has met with only limited success to date, perhaps because only a small portion of the defense arsenal is involved.

"Our discovery of the enzyme that produces the critical early-defense signal, NO, means that we now may be able to regulate the production of this signal.

The turning up of this signal should lead to the turning on of a large portion of the defense arsenal. The end result could be crop plants that can better ward off disease without the use of potentially harmful fungicides and other pesticides, or the introduction of non-plant genes."

Van Wijk, whose research group identified the protein by tandem mass spectrometry, stresses that without the availability of the very sensitive mass spectrometry instruments and the plant genome information "we would not have been able to find this."

The Boyce Thompson Institute was opened in 1924 and is an independent, not-for-profit plant research organization. BTI funding for the Cell research was provided, in part, by a Plants and Human Health Grant from the Triad Foundation.

David Brand | Cornell News
Further information:
http://bti.cornell.edu
http://www.cell.com
http://www.news.cornell.edu/releases/May03/NewGeneKlessig.html

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

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

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>