This discovery has broad implications in a wide range of fields, including medical gene therapy and bioengineering of crop plants. The discovery could be especially useful in the production of biofuels, where being able to control the types of cells that develop could yield more useable plant matter.
The research – conducted at the Boyce Thompson Institute for Plant Research (BTI) in collaboration with Duke University and the Universities of Helsinki and Uppsala – was published online in the journal Nature on April 21.
The discovery of this molecular pathway represents the first time researchers have demonstrated that microRNA – small ribonucleic acid molecules that function to turn off genes in an organism – move between cells as a regulatory signal.
"Many organisms are made up of multiple types of cells, and we do not yet fully understand how these cells are put in the right places, although we believe cells communicate with each other ," said Ji-Young Lee, assistant scientist at BTI and a lead author of the article. "This is the first time anyone has clearly demonstrated cells are communicating through the movement of microRNA. It's likely that this kind of communication process is generally happening in many cell types in many organisms."
The researchers conducted the study in the root of Arabidopsis, a small flowering plant related to cabbage, where they took a closer look at the development of two types of root cells – protoxylem and metaxylem. These are key cells responsible for the transport of water and mineral nutrients in most terrestrial plants. Their goal was to determine the molecular pathway that leads to the differentiation of these two cell types.
Using a combination of molecular and cellular techniques including high-resolution imaging, they discovered a complex sequence of events at the molecular level that creates the distinction between protoxylem and metaxylem cells.
The researchers discovered that a protein molecule called SHORTROOT moves from the vascular cylinder to the endodermis, an inner skin within the root. Once there, it activates another similar protein, SCARECROW. Together, these proteins trigger the creation of the molecule microRNA 165/6. These microRNAs seem to move out of the endodermis as signaling molecules.
MicroRNA 165/6 dissolves a corresponding molecule of messenger RNA, which carries the chemical blueprint for creating proteins. High dosage of these messenger RNA molecules lead cells to become metaxylem, whereas low dosage leads to protoxylem.
Since microRNA 165/6 moves out from its source cells and dissolves their target messenger RNAs, in areas where there are high levels of microRNA 165/6, nearby cells are more likely to become protoxylem. In areas where there are lower levels of microRNA 165/6,cells turn into metaxylem.
There is reason to think that these interactions were key in the evolutionary transition from water dependent mosses to plants that grow as tall as Giant Sequoias 450 million years ago. That's because the layer of cells the researchers studied builds a waterproof tube through which plants can carry water from roots to branches, leaves and flowers.
Other lead authors of the article include Annelie Carlsbecker of Uppsala University, Yrjo Helariutta of Helsinki University and Philip N. Benfey of Duke University. BTI post doctoral associate Jose Sebastian and graduate student Jing Zhou also contributed to the paper.
You can find the full article online at http://www.nature.com/nature/journal/vaop/ncurrent/index.html
Lorraine S. Johnson | EurekAlert!
Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel
Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
26.04.2017 | Materials Sciences
26.04.2017 | Agricultural and Forestry Science
26.04.2017 | Physics and Astronomy