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
Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex
New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences