Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Great mystery of a plant defence pathway unravelled

03.06.2013
Together with several partners, scientists from Wageningen UR (University & Research centre) have discovered that RLP-receptors located at the outside of plant cells and playing an important role in plant defence, join forces with other proteins present at the same location to warn the plant when a fungus attacks.

This finally answers a question that has been haunting several plant scientists around the world for many years. The findings provide new leads for breeding crops with an improved defence against diseases caused by pathogenic microbes.

Plants are constantly challenged by pathogens such as fungi and bacteria. They almost always succeed in warding off pathogens by using special receptors, either present at the outside or inside of the plant cell, to identify the pathogen.

The receptors located at the outside usually also have a domain that protrudes through the cell membrane into the cell. This is used to warn the cell and stimulate the plant cell to take action. This generally results in a ‘programmed cell death’, ensuring that the fungus, for example, can no longer enter the cell and absorb nutrients.

Although much is known about the defence system of plants, there are still quite some mysteries to be solved. For some time, for instance, we know about the existence of so-called RLK-receptors. These receptors are located at the cell membrane of the plant cells and have a domain on both the inside and the outside of the cell. Whenever they receive a signal on the outside - from a fungus, for example - the part on the inside of the cell (the kinase) activates the signal to mount a defence response against the invading fungus.

In addition to RLK-receptors there are also RLP-receptors. These are also located at the cell membrane, but they do not have a kinase domain on the inside of the cell to pass on signals. For over twenty years, scientists have been mystified as to how these receptors manage to warn the plant to enable it to protect itself against pathogens.

The first RLP-receptor was identified in tomato plants about 20 years ago. We now know that all plant species contain such RLPs. For example, tomato contains around 180 different RLPs. Scientists developed the hypothesis that RLP-receptors involved in defence against attacking microbes possibly work together with RLK-receptors to pass on signals, but such an RLK-receptor remained to be identified. After purifying an RLP-receptor complex from leaves of tomato plants, Wageningen UR scientists have now discovered that a number of RLP-receptors do indeed recruit an RLK-receptor, referred to as SOBIR1, in order to warn the cell for fungal attacks.

Switching off the gene for this RLK-receptor cause the RLP-receptors to be non-functional. The scientists have hereby shown that RLP-receptors cannot warn the cell without cooperating with SOBIR1 and their research results have been published in the scientific journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).

As all plant species use RLP-receptors to protect themselves against pathogens, and all contain a gene closely related to SOBIR1, this RLK-receptor is highly likely to be an essential and universal link in the defence system of plants. The discovery therefore provides many opportunities for further studies on this type of defence system. Once more is known about the essential links in plant defence systems, it will be easier to breed plants that are more resistant to pathogenic microbes, which in turn would lead to a reduced use of pesticides. The Wageningen UR scientists will now continue to study what exactly occurs in the plant cells once the SOBIR1 kinase sends out warning signals.

The research was performed by scientists from the Laboratory of Phytopathology, together with colleagues from Plant Research International (PRI), the Centre for BioSystems Genomics (CBSG) and the Sainsbury Laboratory in the UK. It was financed by the Centre for BioSystems Genomics (CBSG), the Netherlands Organisation for Scientific Research (NWO) and the Gatsby Charitable Foundation.

Notes for the editor
Publication
Liebrand, T et al., (2013). Receptor-like kinase SOBIR1/EVR interacts with receptor-like proteins in plant immunity against fungal infection. Proceedings of the National Academy of Sciences. doi: 10.1073/pnas.1220015110
Link to the article in PNAS
http://www.pnas.org/content/early/2013/05/22/1220015110.abstract.html?etoc
Images (can be used freely)
https://picasaweb.google.com/115915961286327465946/GreatMysteryInPlantDefenceU?authuser=0&feat=directlink
Contact
For more information you can contact Paulien Poelarends, communication department Plant Sciences Group, part of Wageningen UR. Paulien.poelarends@wur.nl / +31 317481292

The mission of Wageningen UR (University & Research centre) is ‘To explore the potential of nature to improve the quality of life’. Within Wageningen UR, nine research institutes – both specialised and applied – have joined forces with Wageningen University to help answer the most important questions in the domain of healthy food and living environment. With approximately 40 locations (in the Netherlands, Brazil and China), 6500 members of staff and 10,000 students, Wageningen UR is one of the leading organisations in its domain worldwide. The integral approach to problems and the cooperation between the exact sciences and the technological and social disciplines are at the heart of the Wageningen Approach.

Paulien Poelarends | Wageningen University
Further information:
http://www.wur.nl

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>