Much as adrenaline coursing through our veins drives our body’s reactions to stress, the plant hormone abscisic acid (ABA) is behind plants’ responses to stressful situations such as drought, but how it does so has been a mystery for years.
Scientists at the European Molecular Biology Laboratory (EMBL) in Grenoble, France, and the Consejo Superior de Investigaciones Cientificas (CSIC) in Valencia, Spain discovered that the key lies in the structure of a protein called PYR1 and how it interacts with the hormone. Their study, published online today in Nature, could open up new approaches to increasing crops’ resistance to water shortage.
Under normal conditions, proteins called PP2Cs inhibit the ABA pathway, but when a plant is subjected to drought, the concentration of ABA in its cells increases. This removes the brake from the pathway, allowing the signal for drought response to be carried through the plant’s cells. This turns specific genes on or off, triggering mechanisms for increasing water uptake and storage, and decreasing water loss. But ABA does not interact directly with PP2Cs, so how does it cause them to be inhibited? Recent studies had indicated that the members of a family of 14 proteins might each act as middle-men, but how those proteins detected ABA and inhibited PP2Cs remained a mystery – until now.
A group of scientists headed by José Antonio Márquez from EMBL Grenoble and Pedro Luis Rodriguez from CSIC looked at one member of this family, a protein called PYR1. When they used X-ray crystallography to determine its 3-dimensional structure, the scientists found that the protein looks like a hand. In the absence of ABA, the hand remains open, but when ABA is present it nestles in the palm of the PYR1 hand, which closes over the hormone as if holding a ball, thereby enabling a PP2C molecule to sit on top of the folded fingers. As these features seem to be conserved across most members of this protein family, these findings confirm the family as the main ABA receptors. Moreover, they elucidate how the whole process of stress response starts: by binding to PYR1, ABA causes it to hijack PP2C molecules, which are therefore not available to block the stress response.
“If you treat plants with ABA before a drought occurs, they take all their water-saving measures before the drought actually hits, so they are more prepared, and more likely to survive that water shortage – they become more tolerant to drought”, Rodriguez explains. “The problem so far”, Márquez adds, “has been that ABA is very difficult – and expensive – to produce. But thanks to this structural biology approach, we now know what ABA interacts with and how, and this can help to find other molecules with the same effect but which can be feasibly produced and applied.”
To determine the structure of PYR1, the scientists made use of the infrastructure of the Partnership for Structural Biology, including EMBL Grenoble’s high-throughput crystallisation facilities and the beamlines at the European Synchrotron Radiation Facility, located in the same campus as EMBL Grenoble.
Sonia Furtado | EMBL Press
How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH
A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
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...
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...
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...
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)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
23.06.2017 | Physics and Astronomy
23.06.2017 | Physics and Astronomy
23.06.2017 | Information Technology