Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Soft Matter and its Interface with Biology

11.05.2007
To understand how biological systems work, Jaques Prost, professor of biological physics and managing director at the Ecole Supérieure de Physique et de Chimie Industrielles in Paris, is developing theoretical tools and new experiments to extract physical laws governing the morphology and dynamics of biological cells.

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
Further information:
http://www.iop.org/EJ/journal/EPL

More articles from Physics and Astronomy:

nachricht CCNY physicists master unexplored electron property
26.07.2017 | City College of New York

nachricht Large, distant comets more common than previously thought
26.07.2017 | University of Maryland

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

Large-Mouthed Fish Was Top Predator After Mass Extinction

26.07.2017 | Earth Sciences

Getting closer to porous, light-responsive materials

26.07.2017 | Materials Sciences

Large, distant comets more common than previously thought

26.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>