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 Nanocages in the lab and in the computer: how DNA-based dendrimers transport nanoparticles
19.10.2018 | University of Vienna

nachricht Less animal experiments on the horizon: Multi-organ chip awarded
19.10.2018 | Fraunhofer-Institut für Werkstoff- und Strahltechnik IWS

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Goodbye, silicon? On the way to new electronic materials with metal-organic networks

Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz (Germany) together with scientists from Dresden, Leipzig, Sofia (Bulgaria) and Madrid (Spain) have now developed and characterized a novel, metal-organic material which displays electrical properties mimicking those of highly crystalline silicon. The material which can easily be fabricated at room temperature could serve as a replacement for expensive conventional inorganic materials used in optoelectronics.

Silicon, a so called semiconductor, is currently widely employed for the development of components such as solar cells, LEDs or computer chips. High purity...

Im Focus: Storage & Transport of highly volatile Gases made safer & cheaper by the use of “Kinetic Trapping"

Augsburg chemists present a new technology for compressing, storing and transporting highly volatile gases in porous frameworks/New prospects for gas-powered vehicles

Storage of highly volatile gases has always been a major technological challenge, not least for use in the automotive sector, for, for example, methane or...

Im Focus: Disrupting crystalline order to restore superfluidity

When we put water in a freezer, water molecules crystallize and form ice. This change from one phase of matter to another is called a phase transition. While this transition, and countless others that occur in nature, typically takes place at the same fixed conditions, such as the freezing point, one can ask how it can be influenced in a controlled way.

We are all familiar with such control of the freezing transition, as it is an essential ingredient in the art of making a sorbet or a slushy. To make a cold...

Im Focus: Micro energy harvesters for the Internet of Things

Fraunhofer IWS Dresden scientists print electronic layers with polymer ink

Thin organic layers provide machines and equipment with new functions. They enable, for example, tiny energy recuperators. In future, these will be installed...

Im Focus: Dynamik einzelner Proteine

Neue Messmethode erlaubt es Forschenden, die Bewegung von Molekülen lange und genau zu verfolgen

Das Zusammenspiel aus Struktur und Dynamik bestimmt die Funktion von Proteinen, den molekularen Werkzeugen der Zelle. Durch Fortschritte in der...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Conference to pave the way for new therapies

17.10.2018 | Event News

Berlin5GWeek: Private industrial networks and temporary 5G connectivity islands

16.10.2018 | Event News

5th International Conference on Cellular Materials (CellMAT), Scientific Programme online

02.10.2018 | Event News

 
Latest News

Nanocages in the lab and in the computer: how DNA-based dendrimers transport nanoparticles

19.10.2018 | Life Sciences

Thin films from Braunschweig on the way to Mercury

19.10.2018 | Physics and Astronomy

App-App-Hooray! - Innovative Kits for AR Applications

19.10.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>