Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists unveil a molecular mechanism that controls plant growth and development

31.01.2014
Researchers from Spain and the Netherlands reveal how auxin hormone-regulated proteins activate developmental genes in plants

A joint study published in Cell by the teams headed by Miquel Coll at the Institute for Research in Biomedicine (IRB Barcelona) and the Institute of Molecular Biology of CSIC, both in Barcelona, and Dolf Weijers at the University of Wageningen, in the Netherlands, unravels the mystery behind how the plant hormones called auxins activate multiple vital plant functions through various gene transcription factors.


This shows the atomic structure of an ARF/DNA complex. Auxins control the growth and development of plants through ARF

Credit: (Author: R. Boer, IRB/CSIC)

Auxins are plant hormones that control growth and development, that is to say, they determine the size and structure of the plant. Among their many activities, auxins favor cell growth, root initiation, flowering, fruit setting and delay ripening. Auxins have practical applications and are used in agriculture to produce seedless fruit, to prevent fruit drop, and to promote rooting, in addition to being used as herbicides. The biomedical applications of these hormones as anti-tumor agents and to facilitate somatic cell reprogramming (the cells that form tissues) to stem cells are also being investigated.

The effects of auxins in plants was first observed by Darwin in 1881, and since then this hormone has been the focus of many studies. However, although it was known how and where auxin is synthesized in the plant, how it is transported, and the receptors on which it acts, it was unclear how a hormone could trigger such diverse processes.

At the molecular level, the hormone serves to unblock a transcription factor, a DNA-binding protein, which in turn activates or represses a specific group of genes. Some plants have more than 20 distinct auxin-regulated transcription factors. They are called ARFs (Auxin Response Factors) and control the expression of numerous plant genes in function of the task to be undertaken, that is to say, cell growth, flowering, root initiation, leaf growth etc.

Using the Synchrotron Alba, near Barcelona, and the European Synchrotron Radiation Facility, in Grenoble, Dr. Miquel Coll, a structural biologist and his team analyzed the DNA binding mode used by various ARFs. For this purpose, the scientists prepared crystals of complexes of DNA and ARF proteins obtained by Dolf Weijers team in Wageningen, and then shot the crystals with high intensity X-rays in the synchrotron to resolve their atomic structure. The resolution of five 3D structures has revealed why a given transcription factor is capable of activating a single set of genes, while other ARFs that are very similar with only slight differences trigger a distinct set.

"Each ARF recognizes and adapts to a particular DNA sequence through two binding arms or motifs that are barrel-shaped, and this adaptation differs for each ARF," explains Roeland Boer, postdoctoral researcher in Miquel Coll's group at IRB Barcelona, and one of the first authors of the study.

The ARF binding mode to DNA has never been described in bacteria or animals. "It appears to be exclusive to plants, but we cannot rule out that it is present in other kingdoms. Our finding is highly relevant because we have revealed the ultimate effect of a hormone that controls plant development on DNA, that is to say, on genes." says Miquel Coll.

Reference article: Structural basis for DNA binding specificity by the auxin-dependent ARF transcription factors
D. Roeland Boer, Alejandra Freire-Rios, Willy van den Berg, Terrens Saaki, Iain W. Manfield, Stefan Kepinski, Irene López-Vidrieo, Jose Manuel Franco, Sacco C. de Vries, Roberto Solano, Dolf Weijers, and Miquel Coll

Cell (2014) http://dx.doi.org/10.1016/j.cell.2013.12.027

More information: Sònia Armengou. Oficina de prensa.Institut de Recerca Biomèdica (IRB). 93 403 72 55/ 618 294 070

armengou@irbbarcelona.org

Sònia Armengou | EurekAlert!
Further information:
http://www.irbbarcelona.org

More articles from Life Sciences:

nachricht Making fuel out of thick air
08.12.2017 | DOE/Argonne National Laboratory

nachricht ‘Spying’ on the hidden geometry of complex networks through machine intelligence
08.12.2017 | Technische Universität Dresden

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>