Plants are stakeholders in a subtle and complex chemical warfare to secure optimal growth conditions. Although it has been known for decades that plants produce and release chemical substances to fight their neighbors, it has remained unclear how exactly these compounds act on other plants. A team of German and French scientists has been able to show that one particular class of plant toxins slows down the development of competing plants by specifically acting on the structure of their genome.
Plants are in a constant competition with their neighbors for limited resources such as light, nutrients and water. Only the fittest survive and reproduce. To defend their territory against invading competitors, plants employ so-called allelochemicals, toxic compounds that can inhibit growth and development of other plants. The existence of this chemical warfare, referred to as ‘allelopathy’, is widespread among many plant species, and has been known for a long time to scientists and agriculturists.
To have an advantage over their neighbors, some plant species release chemicals from their roots (e.g. DIBOA). These compounds can get degraded in the soil and turn into toxic substances.
Claude Becker, Sebastián Petersen (Max Planck Institute for Developmental Biology) and Markus Burkard (University Hospital Tübingen)
Plants are able to release chemical compounds from their roots into the soil, where the substances decay or are modified by microbes. Some of these products are toxic when the roots of neighboring plants take them up. Work by Sascha Venturelli and colleagues now sheds light on the inner workings of this plant chemical warfare (The Plant Cell).
Claude Becker, one of the leaders of the study, explains the importance of the findings: “The phenomenon has been known for years, and many classes of allelochemicals have been identified over the last decades, but for first time we now understand the molecular mechanism of such a ‘territorial behaviour’ of plants”.
The scientists investigated the role a specific class of plant secondary metabolites, the cyclic hydroxamic acids DIBOA and DIMBOA. These are released by several grass species, and their degradation products are well known for their phytotoxicity.
Through structural and biochemical analyses, followed by physiological experiments, Venturelli and colleagues could show that these compounds inhibit the activity of so-called histone deacetylases. These enzymes bind to histones, a group of proteins that together with DNA form the genetic material, also known as chromatin. Histone deacetylases remove acetyl side chains from these histones, causing compaction of the DNA and leading to a reduction in gene expression.
In the model plant Arabidopsis thaliana, the scientists found that inhibition of histone deacetylases by the plant toxins lead to more histone acetylation and an increase in gene expression, ultimately causing plant growth to slow down. The study thus not only presents the first molecular mechanism for allelopathy, but also illustrates how environmental toxins can alter chromatin structure and gene expression.
Allelochemicals are important regulators in natural and agricultural plant communities, and have repeatedly been associated with the success of invasive species in their new habitats. But there is more: “Herbal natural products in general hold great potential for the therapy of human diseases”, says Sascha Venturelli from the University Clinics Tübingen, medical scientist and first author of the study, and continues: “We have found that these particular compounds efficiently inhibit the growth of human cancer cells, too.”
Indeed some inhibitors of histone deacetylases have already been approved as anti-cancer drugs. Michael Bitzer and Ulrich Lauer, initiators and co-advisors of the study explain on-going efforts: “Clinical trials at the University Clinics Tübingen currently assess the efficacy of these plant toxins in cancer patients”. Understanding the mode of action of plant toxins could therefore also be of wider significance for medical research.
Contributing authors and institutes:
Sascha Venturelli, Alexander Berger, Kyra von Horn, Ulrich M. Lauer and Michael Bitzer from the Department of Internal Medicine I, Medical University Clinic, University of Tübingen, Germany;
Regina G. Belz from the Institute of Plant Production and Agroecology in the Tropics and Subtropics, University of Hohenheim, Stuttgart, Germany;
Andreas Kämper, André Wegner and Oliver Kohlbacher from the Applied Bioinformatics Group, University of Tübingen, Tübingen, Germany;
Alexander Böcker from the Evotec AG, Hamburg, Germany;
Gérald Zabulon and Fredy Barneche from the Institut de Biologie de l’Ecole Normale Supérieure (IBENS), CNRS, Paris, France;
Tobias Langenecker, Detlef Weigel and Claude Becker from the Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
Venturelli et al.
Plants release precursors of histone deacetylase inhibitor to suppress growth of competitors
Advance Publication, The Plant Cell, November 2015 tpc.15.00585
Nadja Winter (PR Officer)
Phone: +49 7071 601-444
Nadja Winter | Max-Planck-Institut für Entwicklungsbiologie
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
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...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences