In the beginning is the fertilized egg cell. Following numerous cell divisions, it then develops into a complex organism with different organs and tissues. The largely unexplained process whereby the cells simply "know" the organs into which they should later develop is an astonishing phenomenon. Scientists from the Center for Plant Molecular Biology (ZMBP) of the University of Tübingen and the University of Wageningen, in cooperation with colleagues from the Max Planck Institute for Developmental Biology, have investigated how this process is controlled. Based on their studies of the thale cress, Arabidopsis thaliana, they have succeeded in demonstrating how the plant forms its first roots: the root founder cell in the tiny group of cells contained in the seed is activated by a combination of a plant hormone and a transcription factor. These insights could contribute to the breeding of plants with a particularly effective root system in the future. (Nature, advance online publication on March 10, 2010)
In the seed of the thale cress, the embryo forms from the fertilised egg cell that initially divides into two daughter cells. One of these two cells later goes on to form almost the entire embryo, while the other generates connective tissue that anchors the embryo in the endosperm or nutritive tissue. When the embryo has grown into a small cluster of cells, the connective tissue cell that borders the embryo is stimulated by activating signals to become part of the embryo and form the root tissue. The scientists studied these processes in detail under the supervision of Gerd Jürgens and Dolf Weijers and succeeded in identifying several of the players involved in this complex regulatory network.
The formation of the root tissue depends firstly on the accumulation of the plant hormone auxin, which is channelled to the root founder cell by the embryo. This process is reinforced by the transcription factor MONOPTEROS. However, this is not sufficient on its own. The researchers concluded that MONOPTEROS must deliberately activate other genes. In a comprehensive survey of all of the genes activated by MONOPTEROS, they identified two genes that already play a role in embryonic development: TMO5 and TMO7 (TMO = Target of MONOPTEROS). Both of these genes are required for the formation of the root tissue. For this purpose, the protein formed by the TMO7 gene must migrate from the location of its emergence in the embryo to the root founder cell. "With TM07 we have identified a hitherto unknown intercellular signal for root formation in the embryo," says Gerd Jürgens. The detective work in the plant researchers’ genetics laboratory does not end here, however. "Because the transcription factor TM07 is involved in other regulatory network of plant development, there can be no doubt that it holds further insights in store for us," says Jürgens.
Original work:Alexandra Schlereth, Barbara Möller, Weilin Liu, Marika Kientz, Jacky Flipse, Eike H. Rademacher, Markus Schmid, Gerd Jürgens und Dolf Weijers
Nature, advance online publication on March 10th, 2010, doi 10.1038/nature08836
Contact:Prof. Dr. Gerd Jürgens
Barbara Abrell | EurekAlert!
Scientists enlist engineered protein to battle the MERS virus
22.05.2017 | University of Toronto
Insight into enzyme's 3-D structure could cut biofuel costs
19.05.2017 | DOE/Los Alamos National Laboratory
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...
For the first time, scientists have succeeded in studying the strength of hydrogen bonds in a single molecule using an atomic force microscope. Researchers from the University of Basel’s Swiss Nanoscience Institute network have reported the results in the journal Science Advances.
Hydrogen is the most common element in the universe and is an integral part of almost all organic compounds. Molecules and sections of macromolecules are...
22.05.2017 | Event News
17.05.2017 | Event News
16.05.2017 | Event News
22.05.2017 | Materials Sciences
22.05.2017 | Life Sciences
22.05.2017 | Physics and Astronomy