Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

MicroRNAs in plants: Regulation of the regulator

09.11.2012
A phosphate switch to fine-tune the protein production in the cells

MicroRNAs are essential regulators of the genetic program in multicellular organisms. Because of their potent effects, the production of these small regulators has itself to be tightly controlled.

That is the key finding of a new study performed by Tübingen scientists at the Max Planck Institute for Developmental Biology. They identified a new component that modulates the production of micro RNAs in thale cress, Arabidopsis thaliana, by the removal of phosphate residues from a micro RNA-biogenesis enzyme. This can be as quick as the turn of a switch, allowing the plant to adapt to changing conditions. In this study, the scientists combined advanced imaging for facile detection of plants with defective microRNA activity with whole genome sequencing for rapid identification of new mutations.

The cell seems to thwart itself: Reading the DNA, a mobile messenger RNA is produced in the cell nucleus, exported to the cytoplasm where it serves as a blueprint for the production of proteins. At the same time, the cell is able to produce micro RNAs that, by binding to specific messenger RNAs, can block protein production or even initiate its destruction. But why does the cell start a costly process and immediately stops it? "Well, the answer lies on the fine balance the cell has to achieve between producing a protein and avoid having an excess of it. Reaching the right level of a protein and its adequate temporal and spatial distribution requires, sometimes, opposed forces," says Pablo Manavella, first author of the study and postdoc in the department of Detlef Weigel at the Max Planck Institute for Developmental Biology. "Once the transcript of the messenger RNA is activated it is quite stable. If you need a quick stop, regulatory mechanisms, such as the micro RNAs, will be able to hold up the process," he explains. The study was carried out in collaboration with scientists from the Center for Plant Molecular Biology (ZMBP) and the Proteome Center of the University of Tübingen.

The production of micro RNAs from its precursors has already been extensively studied, especially in animal cells. "Micro RNAs in plants have evolved in parallel and independently. We had to assume that they could be processed in a different way," Pablo Manavella explains.

The scientists used a methodical trick to study the activity of micro RNAs in cells of thale cress plants. First, they developed a reporter system based on the bioluminescent protein luciferase from firefly; its DNA was integrated in the plant cells. Secondly, the scientists inserted in the plant genome a fragment of DNA containing a precursor of an artificial micro RNA that specifically inhibits luciferase. These plants thus initially showed no light emission despite containing the genes encoding luciferase. In a mass experiment, the scientists then triggered unspecific mutations in thousands of plants. With the aid of a special hypersensitive camera the few shining plants were sorted out. "In all these individuals some part of the micro RNA pathway must have been damaged so that luciferase was no longer silenced by the artificial micro RNA," says Pablo Manavella.

To identify the genes responsible for the failure in silencing luciferase, the scientists made use of a new technology developed at the Max Planck Institute, which enables the rapid detection of causal mutations by whole-genome sequence analysis. "Just a few years ago, this project would have been difficult to complete within two years. Nowadays, whole genome sequencing is a rapid and affordable method. By combining the screening test on luciferase activity with whole genome sequencing we could reduce the study period from years to several months," Pablo Manavella explains. Among the obtained mutants the scientists identified the phosphatase CPL1 as a key component of the microRNA biogenesis pathway. This protein modulates the production of these molecules by removing phosphate residues from HYL1, one of the main co-factors in the pathway, impairing the production of micro RNAs. Once produced these micro RNAs will bind to the corresponding messenger RNAs stopping the production of the protein.

"We have identified one factor able to regulate the activity of the regulators," Pablo Manavella summarizes their results. Micro RNAs represent only one of the of genetic regulation mechanisms among many others; however, in the manner of a switch they provide quick and efficient answers to changing requirements, for example in many developmental processes. In general, micro RNAs in plants are much more specific than in animals, the scientists say. "Plants cannot run away when facing a stressful condition. Therefore they need quick ways to regulate its genes in order to adapt to such situations."
Contact
Dr. Pablo Manavella
Max Planck Institute for Developmental Biology, Tübingen
Phone: +49 7071 601-1405
Email: pablo.manavella@­tuebingen.mpg.de
Prof. Dr. Detlef Weigel
Max Planck Institute for Developmental Biology, Tübingen
Phone: +49 7071 601-1410
Email: detlef.weigel@­tuebingen.mpg.de
Janna Eberhardt
Max Planck Institute for Developmental Biology, Tübingen
Phone: +49 7071 601-444
Fax: +49 7071 601-359
Email: presse-eb@­tuebingen.mpg.de
Original publication
Pablo A. Manavella, Jörg Hagmann, Felix Ott, Sascha Laubinger, Mirita Franz, Boris Macek, Detlef Weigel
Fast-forward genetics identifies plant CPL phosphatases as regulators of miRNA processing factor HYL 1

Cell, Vol. 151, 4

Dr. Pablo Manavella | EurekAlert!
Further information:
http://www.mpg.de/6616426/micro-RNAs-plants

More articles from Life Sciences:

nachricht How to become a T follicular helper cell
31.07.2015 | La Jolla Institute for Allergy and Immunology

nachricht Heating and cooling with light leads to ultrafast DNA diagnostics
31.07.2015 | University of California - Berkeley

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Gefangen in Ruhelosigkeit

Mit ultrakalten Atomen lässt sich ein neuer Materiezustand beobachten, in dem das System nicht ins thermische Gleichgewicht kommt.

Was passiert, wenn man kaltes und heißes Wasser mischt? Nach einer Weile ist das Wasser lauwarm – das System hat ein neues thermisches Gleichgewicht erreicht....

Im Focus: Quantum Matter Stuck in Unrest

Using ultracold atoms trapped in light crystals, scientists from the MPQ, LMU, and the Weizmann Institute observe a novel state of matter that never thermalizes.

What happens if one mixes cold and hot water? After some initial dynamics, one is left with lukewarm water—the system has thermalized to a new thermal...

Im Focus: Superschneller Wellenritt im Kristall: Elektronik auf Zeitskala einzelner Lichtschwingungen möglich

Physikern der Universitäten Regensburg und Marburg ist es gelungen, die von einem starken Lichtfeld getriebene Bewegung von Elektronen in einem Halbleiter in extremer Zeitlupe zu beobachten. Dabei konnten sie ein grundlegend neues Quantenphänomen entschlüsseln. Die Ergebnisse der Wissenschaftler sind jetzt in der renommierten Fachzeitschrift „Nature“ veröffentlicht worden (DOI: 10.1038/nature14652).

Die rasante Entwicklung in der Elektronik mit Taktraten bis in den Gigahertz-Bereich hat unser Alltagsleben revolutioniert. Sie stellt jedoch auch Forscher...

Im Focus: On the crest of the wave: Electronics on a time scale shorter than a cycle of light

Physicists from Regensburg and Marburg, Germany have succeeded in taking a slow-motion movie of speeding electrons in a solid driven by a strong light wave. In the process, they have unraveled a novel quantum phenomenon, which will be reported in the forthcoming edition of Nature.

The advent of ever faster electronics featuring clock rates up to the multiple-gigahertz range has revolutionized our day-to-day life. Researchers and...

Im Focus: Erster Nachweis von Lithium in einem explodierenden Stern

Erstmals konnte das chemische Element Lithium in der ausgestoßenen Materie einer Nova nachgewiesen werden. Beobachtungen von Nova Centauri 2013 mit Teleskopen des La Silla-Observatoriums der ESO und in der Nähe von Santiago de Chile helfen bei der Aufklärung des Rätsels, warum so viele junge Sterne mehr von diesem Element enthalten als erwartet. Diese Entdeckung liefert ein seit langem fehlendes Teil im Puzzle der chemischen Entwicklungsgeschichte unserer Galaxie und ist ein großer Fortschritt für das Verständnis des Mischungsverhältnisses der chemischen Elemente in den Sternen unserer Milchstraße.

Das leichte chemische Element Lithium ist eines der wenigen Elemente, das nach unserer Modellvorstellung auch beim Urknall vor 13,8 Milliarden Jahren...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Türme und Maste aus Stahl – Neues aus Forschung und Anwendung

31.07.2015 | Veranstaltungen

Tagung „Brandschutz im Tank- und Gefahrgutlager“ am 16. November 2015 im Essener Haus der Technik stellt praktische Lösungen vor

30.07.2015 | Veranstaltungen

12. BMBF-Forum für Nachhaltigkeit: Green Economy, Energiewende und die Zukunft der Städte

30.07.2015 | Veranstaltungen

 
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Gefangen in Ruhelosigkeit

31.07.2015 | Physik Astronomie

RNA-bindendes Protein beeinflusst zentralen Mediator zellulärer Entzündungs- und Stressreaktionen

31.07.2015 | Biowissenschaften Chemie

Dem Altern auf den Fersen

31.07.2015 | Biowissenschaften Chemie