"For years people have been trying to understand this beautiful formation," said Dr. Enrico Scarpella, from the U of A's Department of Biological Sciences. "We were able to connect the mechanism responsible for the initiation of the veins in the leaf with that of formation of the shoot and root. With our piece of the puzzle added, it indeed seems the same mechanism is responsible for all these events."
What Scarpella and his research team--Dr. Thomas Berleth's group from the University of Toronto and Dr. Jiri Friml from the University of Tuebingen--discovered has interested scientists around the world. For several years it has been known that a hormone called auxin stimulated the formation of the veins. "It was believed that auxin would behave like man--build the streets on which man himself would travel," said Scarpella. "However, the theory argued that in each individual vein auxin could only run one way at any given time, making them sort of alternate one-way streets."
By labeling the protein that transports the hormone auxin with a fluorescent tag, he could then shine a light on the leaves and watch how auxin was being transported during vein formation. Thanks to this approach, the team identified cells within individual veins that transport the hormone auxin in two opposite directions. He also showed for the first time that the epidermis of the leaf is very important in the transport of this hormone and in the formation of the veins.
One of the objections to the idea that veins might act as a channel to transport auxin was that there were mutant leaves that produced dotted, rather than continuous veins for auxin to run through. But the research team showed that the leaves with the dotted veins were a mature version and that at an earlier stage, the veins were continuous and did act as transporters. "We didn't have the technology to see those early stages before and now we do," he said. "We now know that the veins are the backbone of the leaf and are somehow responsible for the final shape of the plant."
But one of the biggest discoveries, perhaps the one with the most evolutionary implications, is that plants use the same mechanism to regulate vein formation in the leaf and branch formation on the main trunk and on the main root. The finding that the leaf is like a two-dimensional model of a tree may change the way plant scientists work, says Scarpella. "If each leaf can make more than 100 veins, you can see the process over and over compared to the formation of branches in a big, three-dimensional slowly growing tree or the difficulties in studying root branching in their natural environment, which is the dirt," he said. "Our findings will contribute to the way we will manipulate plant development to our advantage. Once we know all the players in the game we will be able to say, we want more leaves on this, more branches on this one or fewer flowers on this plant."
Phoebe Dey | EurekAlert!
'Y' a protein unicorn might matter in glaucoma
23.10.2017 | Georgia Institute of Technology
Microfluidics probe 'cholesterol' of the oil industry
23.10.2017 | Rice University
Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
23.10.2017 | Event News
17.10.2017 | Event News
10.10.2017 | Event News
23.10.2017 | Life Sciences
23.10.2017 | Physics and Astronomy
23.10.2017 | Health and Medicine