Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Unraveling plant reactions to injury

30.05.2011
Identification of a key compound that regulates plant responses to wounding could provide benefits on three fronts

Better understanding of plant defense systems, and the potential to generate stress-tolerant plants and even new malaria drugs, may all stem from the documentation of a molecular mechanism that plays a significant role in the response of plants to physical injuries, such as cuts. A team of agricultural researchers in Japan, led by Fuminori Takahashi of the RIKEN Plant Science Center in Tsukuba, found that the key protein in the complex mechanism is MPK8, which is fully activated by two signaling pathways working in concert[1].

The researchers showed that MPK8 is activated while the wounded plant mounts an initial emergency response to an injury. Around the fresh wound, the plant produces reactive oxygen species (ROS), such as hydrogen peroxide. These highly toxic compounds kill any pathogens that could access internal tissues via the wound site. However, since ROS can also harm plant tissue they require close regulation. Takahashi and his team—from RIKEN and three Japanese universities—found that the regulator is MPK8.

In addition to the initial response, the injury stimulates the release of calcium ions and starts a cascade of phosphorylation or phosphate-adding compounds. The compounds involved are called mitogen-activated protein kinases (MAPKs). MPK8 is one of the MAPKs of the model plant Arabidopsis.

Takahashi and his colleagues used Arabidopsis plants to investigate how both signaling and the levels of ROS are regulated after physical injury. Using plants into which they had introduced additional copies of the MPK8 gene, the researchers showed that MPK8 was activated under stress, particularly from physical wounding. MPK8 was strongly activated by MKK3, another MAP kinase from higher up the cascade. But it was also activated by calcium ions, specifically when they were bound to proteins called calmodulins. In addition, the researchers determined that the production of MPK8 was associated with regulation of ROS, lowering its accumulation.

A region of MPK8 known as TDY is known to interact or be phosphorylated with both MKK3 and calcium-bound calmodulins. By inhibiting each of these compounds in turn, the researchers showed that full activation of MPK8 demanded activating both of them at once, bringing the signaling pathways together. Finally, by examining the expression of genes, they found that MPK8 regulates the production of ROS by repressing the gene that stimulates their production (Fig 1).

“We think our findings might eventually lead to designing a drug treatment for malaria infection,” says Takahashi, “because the Plasmodium parasite involved uses the same kind of MAPKs.”

The corresponding author for this highlight is based at the Gene Discovery Research Group, RIKEN Plant Science Center

Journal information

[1] Takahashi, F., Mizoguchi, T., Yoshida, R., Ichimura, K. & Shinozaki, K. Calmodulin-dependent activation of MAP kinase for ROS homeostasis in Arabidopsis. Molecular Cell 41, 649–660(2011).

gro-pr | Research asia research news
Further information:
http://www.riken.jp
http://www.researchsea.com

Further reports about: Arabidopsis plant Arabidopsis thaliana MAP MAPKs MPK8 RIKEN calcium ions signaling pathway

More articles from Life Sciences:

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

nachricht CWRU researchers find a chemical solution to shrink digital data storage
22.06.2017 | Case Western Reserve 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: 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)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

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

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>