Auxin tells shoots to grow away from the ground and toward light and water. Charles Darwin conducted early experiments that showed how auxin affects plant growth. Most plants and animals have an internal clock that allows them to match their activities to the time of day or season of the year.
The circadian rhythms appear to act by "gating" the effect of auxin, the researchers said. In other words, the plant becomes more responsive to auxin at a certain time of day.
Postdoctoral researcher Michael Covington and Stacey Harmer, professor in the Section of Plant Biology at UC Davis, used microarray chips to look at thousands of genes from the laboratory plant Arabidopsis at the same time. About 10 percent showed some regulation by time of day.
In the auxin signaling pathway, nearly every step in the chain of events from the production of auxin through to the final growth response showed some regulation by the clock.
Covington and Harmer made plants that would glow when the auxin signaling was active. They found a natural rhythm of activity, peaking late in the night when water is most available and the plants are preparing for daylight.
A circadian response to auxin was actually observed in 1937 but then forgotten for 70 years, Harmer said. The researchers hope to understand exactly why having a functional internal clock is important for plant health.
Andy Fell | EurekAlert!
Zap! Graphene is bad news for bacteria
23.05.2017 | Rice University
Discovery of an alga's 'dictionary of genes' could lead to advances in biofuels, medicine
23.05.2017 | University of California - Los Angeles
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
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...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
23.05.2017 | Physics and Astronomy
23.05.2017 | Life Sciences
23.05.2017 | Medical Engineering