Genetically identical sibling cells do not always behave the same way. So far this has been attributed to random molecular reactions. Now systems biologists of the University of Zurich have discovered an overlooked consequence of the spatial separation of cells into a nucleus and a cytoplasm. Building on top of this insight they could predict with supercomputers the activity of genes in individual human cells.
Genetically identical cells do not always behave the same way. According to the accepted theory, the reason are random molecular processes – known as random noise. For decades this view has been underpinned by numerous experiments and theoretical models.
Now the system biologists of the University of Zurich have made a momentous discovery: The spatial separation of human cells into a nucleus and cytoplasm creates some kind of passive filter. This filter suppresses the random noise and enables human cells to precisely regulate the activity of individual genes.
Observed more randomness in the nucleus
While the observations of Lucas Pelkmans and his team initially seemed at odds with current text-book knowledge, a second look revealed the missing explanation. During the activation of genes, the genetic information, which has been stored in DNA, becomes transcribed to messenger RNA.
“We could perfectly predict the messenger RNA in the cytoplasm and discovered much more randomness within the nucleus” explains Nico Battich, coauthor and PhD student at Institute of Molecular Biology. “One could envision the nucleus to act as a leaky bucket that on the one hand withholds messenger RNA, but on the other hand enables a delayed and even outflow. Thus the activity of genes in the cytoplasm becomes highly robust against random noise during the formation of messenger RNA in the nucleus.”
Smallest physiological details made visible
Thanks to their novel method, the Zurich scientists were the first ones who could study that many human genes. They managed to detect every single molecule that is produced by active genes. ”Previously one could only study few genes and in many cases these genes had to be genetically modified by researchers” says PhD student Thomas Stoeger.
“We realized that the activity of genes strongly differed between single cells, but could at the same time predict the activity for every single cell by visualizing subtle physiological details with microscopic dyes.”
The findings of the Zurich scientists impact several fields. “For example, evolutionary biology, where the spatial separation of cells marks a milestone in the emergence of intelligent life. But also biotechnology, where a precise control over artificial genes is desirable, and human medicine, if it should become possible to predict which malignant cells will respond to drugs.” concludes Prof. Lucas Pelkmans.
Nico Battich, Thomas Stoeger, Lucas Pelkmans. Control of Transcript Variability in Single Mammalian Cells. Cell. December x, 2015. Doi: 10.1016/j.cell.2015.11.018
Prof. Lucas Pelkmans
Institute of Molecular Life Sciences
University of Zurich
Phone +41 44 635 31 23
Melanie Nyfeler | Universität Zürich
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
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....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences