A new chemical tool to analyze plant hormone pathways is established by Prof. Dr. Markus Kaiser, Centre for Medical Biotechnology, University of Duisburg-Essen (UDE), and Dr. Erich Kombrink, Max Planck Institute for Plant Breeding Research, Cologne. In the latest issue of „Nature Chemical Biology“, the researchers disclose a small molecule inhibitor, which interferes with the activity of the plant hormone jasmonic acid. The approach resembles concepts, which are well established in medical therapy and opens new opportunities for plant research. (Doi:10.1038/nchembio.1591).
Currently, research into plant hormone signalling relies primarily on molecular genetics. Genes of interest are modified or extinguished to then study resultant changes in the plant’s phenotype. This strategy is powerful but has its limitations, as is highlighted by the plant hormone jasmonic acid.
Although jasmonic acid controls a diversity of biological functions, as flower formation, root growth, protection against insect attack and infections, wound healing, plant aging and others, only one signal transduction pathway has been elucidated so far.
This single pathway however is not sufficient to explain the broad spectrum of hormone actions. Other, so far unknown, signaling pathways and mechanisms must exist. To get a better understanding of jasmonic acid’s signaling mechanisms, alternative experimental approaches are therefore required. The teams from Essen and Cologne took up this challenge and used a procedure, which is well established in medical research but still rarely used in plant science:
They searched for a chemical drug that can be used to block a specific signalling pathway. In medicine, such compounds find applications as drugs to treat diseases. In plant science, however, such inhibitors may represent important chemical tools to advance the study of plant signalling pathways.
In the search of candidate inhibitors of jasmonic acid signalling, the scientists performed studies in intact plants. They started with a screening in the ‘model plant’ Arabidopsis thaliana. From 1.728 tested compounds, 16 molecules were identified that impaired jasmonic acid signalling. These were then studied in more detail and finally, only one compound was confirmed as a suitable specific inhibitor.
The compound was called Jarin-1. “Structurally, the compound is a plant alkaloid whose amino groups may carry different side chains” the researchers comment. “The activity of the compound depends on a specific side chain. Modifications deactivate the inhibitor. As a final proof of the active chemical structure, we synthesized it from scratch.’
As a next step the scientists looked for the molecular target of the new inhibitor. The already known signal transduction pathway of jasmonic acid starts with an enzyme called JAR1 that links the plant hormone jasmonic acid to the amino acid isoleucine. The resulting chemical product then modulates the transcription of various genes that together form the particular biological activity of jasmonic acid.
Kombrink and Kaiser were able to show that this enzyme JAR1 is the target of the inhibitor Jarin-1. Inhibition of JAR1 causes depletion of the required jasmonic acid-isoleucine conjugate, thus impairing gene transcription. They furthermore found that the molecule Jarin-1 is not only active in Arabidopsis but also in Candamine hirsuta, lamb’s cress. Therefore, the inhibitor seems to be broadly applicable and thus may be used in future applications to advance the understanding of jasmonic acid signalling.
What is particular about this new approach and caused the renowned journal “Nature Chemical Biology” to publish the work? Small molecules are promising new tools for plant research. The scientists demonstrate exemplarily how to screen for a specific small molecule inhibitor, how to characterize it and how to identify its target protein and they point out possible applications. The scope of the study turns the publication into something highly special.
Dr. Erich Kombrink
Max-Planck-Institut for Plant Breeding Research
Telefon: +49 221 5062 320
Prof. Dr. Markus Kaiser
Center for Medical Biotechnology
Beate Kostka | idw - Informationsdienst Wissenschaft
First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife
Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
25.10.2016 | Earth Sciences
25.10.2016 | Life Sciences
25.10.2016 | Earth Sciences