He described his work at the EPL symposium, “Physics In Our Times” held today (10 May) at the Fondation Del Duca de l’Institut de France, Paris. In particular, he is interested in areas such as cell traffic and motility, cell duplication and oscillations and signal transduction. He wants to know what characterises living systems as opposed to dead ones. One example is how the so-called fluctuation dissipation theorem is violated in a living system.
Much of eukaryotic cell dynamics results from the dynamical interaction of three major cell components. These are phospholipidic membranes, cytoskeletal networks and molecular motors. During his presentation, Prof. Prost gave three examples that illustrate how a quantitative description of basic biological processes can be obtained. He first discussed how molecular motors can pull phospholipidic nanotubes and how to obtain a theoretical description (without adjustable parameters) of this process - known to play an important role in eukaryotic cell traffic.
Next, he discussed cell motion. On a substrate, cells extend a thin layer, called the lamellipodium, which drags the cell forward. Using only symmetry and conservation arguments, he described the concept of “active gels” and discussed the shape and dynamics of the lamellipodium. In particular, he showed how the observed “retrograde flow” of gel naturally emerges out of the theory description.
Using the same framework, Prof. Prost also discussed how oscillations are obtained when cells are suspended in a fluid and suggested that the early stage of mitosis (cell division) is the bipolar manifestation of this same instability.
Prost says his team’s most exciting result to date has been to show that “hair cells” (the cells that detect sound in the inner ear) work with excellent precision at the verge of an oscillation instability - called a “Hopf bifurcation”. This finding explained no less than six previously unanswered questions, some dating from the 18th century.
“It is extremely difficult to drive a system so close to instability in a laboratory experiment,” explained Prost. “However, during evolution our ears have had plenty of time to drive 16 000 cells close to such instabilities! This shows how biology is interesting for physicists - evolution can drive systems under unlikely conditions that are almost inaccessible in the lab.”
Prof. Prost and colleagues have also developed a description of biological gels in which molecular motors provide “life” to these structures. “We are now in a position to raise questions about cell dynamics including cell duplication in terms of condensed matter physics,” he stated.
It is now clear that statistical physics and condensed matter physics are important for understanding biology. Prof. Prost believes that over the next 20 years we will finally be able to describe the connection between specific protein activity and global cell function in a quantitative way. “Such knowledge will have a profound impact on our understanding of pathologies such as cancer and neurodegenerative diseases, and hopefully help us find therapies,” he said.
Dianne Stilwell | alfa
Comet or asteroid? Hubble discovers that a unique object is a binary
21.09.2017 | NASA/Goddard Space Flight Center
First users at European XFEL
21.09.2017 | European XFEL GmbH
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
21.09.2017 | Physics and Astronomy
21.09.2017 | Life Sciences
21.09.2017 | Health and Medicine