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
A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences