Networks are everywhere. Trying to catch connecting flights as we shuttle from one airport to the next can make distances between cities seem even greater than they are. Discovering that you are sitting next to a friend of a friend on one of those flights (social contact networks) can make the world seem a much smaller place. Diverse networks, from airports to social interactions to genes and proteins, often have surprisingly similar structure. In all of these networks, some nodes are highly connected to many other nodes, while most tend to have just a few connections. Molecular biologists have found that the connectedness of genes and proteins is correlated with a range of phenomena, from how essential genes are, to the rates at which they have evolved, to the probability that they are lost over evolutionary time. In the yeast gene regulatory network, some genes are turned on and off by just one ’regulatory gene’ while others are influenced by ten or more regulatory genes. In a study of this network, to be published in the May 2005 issue of American Naturalist, Daniel E. L. Promislow (University of Georgia) now shows that network structure can be used to understand ecological relevant traits.
Promislow analyzes the yeast gene regulatory to understand how genes influence phenotypic plasticity. ’Phenotypic plasticity’ refers to the ability of genetically identical organisms to alter their phenotype in response to an environmental change. For example, genetically identical plants grown in sun versus shade will soon look very different from one another.
It turns out that some species are more plastic than others. Until now, we have not been able to determine what kinds of genes determine whether or not an organism displays phenotypic plasticity. A previous study measured variation in activity level for each of the roughly 6000 genes found in yeast across a range of stressful environments. Some genes varied enormously in their expression levels from one environment to the next, while others were relatively constant. That is, some genes were more plastic than others. Promislow has now discovered that the more regulators a gene has, the more plastic the gene. Furthermore, he shows that the plasticity of a gene depends on its function. From these simple patterns, we gain insight into the complex genetic architecture that determines how well an organism can respond to environmental change.
Carrie Olivia Adams | EurekAlert!
Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides
16.07.2018 | Tokyo Institute of Technology
The secret sulfate code that lets the bad Tau in
16.07.2018 | American Society for Biochemistry and Molecular Biology
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences