Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Good preparation is key – even for plant cells and symbiotic fungi

11.11.2011
Not only mineral oil and petroleum gas, also phosphorous is a scarce resource.

Phosphorous, this important and essential mineral, is part of our DNA and, therefore, irreplaceable. Many soils are already depleted for phosphorous and plants growing on them are only able to take up enough phosphorous by living in symbiosis with arbuscular mycorrhizal fungi (AM fungi). This symbiosis is a non-synchronous process, which means that different cells in the root can show different phases of symbiotic interaction with the fungus. For this reason, the scientists used laser capture microdissection to excise single root cells and deciphered their specific gene activity.

When scientists are analysing the molecular composition of plant cells they usually assume that different cells from the same tissue are alike. In many cases, this assumption is true. The majority of cells from leaves, stems or roots show similar levels of gene expression and metabolic activity. It gets more complicated when plants undergo symbiosis, because interactions with the symbiotic partner may alter the cell’s metabolism. And even cells adjacent to colonised cells that have not yet come into direct contact with the fungus can show drastic changes in their gene expression levels.

The most prevalent plant symbiosis is that between root cells and arbuscular mycorrhizal fungi, called AM fungi. AM fungi make sure that plants can grow on nutrient-depleted soil – unnoticed by most people. These fungi outstretch their filamentary cells, called hyphae, far into the soil and are thereby able to take up more nutrients than plants can absorb with their roots. The fungus takes up mainly phosphate, but possibly also nitrate and metal ions like copper, zinc and iron and gives these willingly to the plant. In return, it is rewarded with sugars that plants produce via photosynthesis.

Interestingly, fungus and plant cell never really merge; they are constantly separated by membranes, the outer boundaries of the cells. To enable the relatively big sugar and phosphate molecules to pass through these membranes, the plant cells insert big protein complexes that resemble tunnels through which the molecules can freely travel from one cell to another. This was already known, and it was not astounding that the scientists around Franziska Krajinski found genes that encode for such transport proteins to be highly expressed in cells that are already colonised by the fungus. A more surprising discovery was, however, that even cells that are in close vicinity of the colonised cells seemed to be already reprogrammed. More than 800 genes showed enhanced activity exclusively in these cells. “The higher transcription rate of genes that are responsible for transport proteins, lipid acid metabolism and gene regulation does not seem to be a result of the colonisation by the fungus,” explains Nicole Gaude, first author of the study. “It is more likely that cells are preparing themselves for an imminent colonisation by the fungus.”

These very precise and specific results were obtained with the help of laser capture microdissection. In this method, a laser beam is used to excise individual cells from a tissue. At least 5000 cells were cut out by Gaude and her team; a time-consuming manual labour that even Sisyphus would have been proud of. But the time and effort were worth it. “We now know which genes are activated even before a symbiosis is physically established,” explains Gaude.

Understanding the symbiotic programme of plants could enable the use of AM fungi in agriculture and reduce the application of expensive, artificial fertilizer in the future.

Contact

Nicole Gaude/Franziska Krajinski
Max-Planck-Institute of Molecular Plant Physiology
Tel. 0331/567 8355
Gaude@mpimp-golm.mpg.de
Krajinski@mpimp-golm.mpg.de
Claudia Steinert
Public Relations
Max-Planck-Institute of Molecular Plant Physiology
Tel. 0331/567 8275
Steinert@mpimp-golm.mpg.de
http://www.mpimp-golm.mpg.de
Original Work
Nicole Gaude, Silvia Bortfeld, Nina Duensing, Marc Lohse, Franziska Krajinski
Arbuscule-containing and non-colonized cortical cells of mycorrhizal roots undergo a massive and specific reprogramming during arbuscular mycorrhizal development

The Plant Journal, Advanced Online Publication 06 October, DOI: 10.1111/j.1365-313X.2011.04810.x

Ursula Ross-Stitt | Max-Planck-Institut
Further information:
http://www-en.mpimp-golm.mpg.de/

More articles from Life Sciences:

nachricht Individual Receptors Caught at Work
19.10.2017 | Julius-Maximilians-Universität Würzburg

nachricht Rapid environmental change makes species more vulnerable to extinction
19.10.2017 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>