Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Small signaling molecule gives green light for cell division

07.05.2015

Generating offspring is the evolutionary goal of all living organisms. The multiplication of individual cells is coordinated by the cell cycle. For the discovery of how this process is regulated in eukaryotes the Noble Prize was awarded in 2001.

The team of Prof. Urs Jenal at the Biozentrum of the University of Basel has now identified the central switch for reproduction in bacteria. While cell cycle progression in eukaryotes is regulated by small proteins called cyclins, in bacteria this role is adopted by a small signaling molecule, c-di-GMP. In the current issue of «Nature» the scientists describe the molecular details of this process.


Enzymes producing the small signalling molecule c-di-GMP (yellow) control Caulobacter cell cycle.

University of Basel, Biozentrum

Though very tiny, the molecule is vital for the survival of almost all bacteria. This signaling messenger – called c-di-GMP – controls behavioral processes in bacteria. For instance, it ensures that bacteria join together to form biofilms, which can cause chronic infections in humans.

The scientists working with Prof. Urs Jenal at the Biozentrum of the University of Basel have now demonstrated that c-di-GMP also plays a decisive role in bacterial reproduction. They discovered that oscillating levels of the messenger subsequently influence the activity of key regulatory proteins, thereby controlling cell cycle progression and proliferation of bacteria.

Signaling molecule sets traffic lights at check points

How do cells multiply? When cells divide, two daughter cells arise from one mother cell. Before this, however, the cell must go through several phases from growth, to the replication of its genetic information and finally to cell division.

This process is known as the cell cycle. In their study on the model bacterium Caulobacter crescentus the infection biologists show for the first time, that the signaling messenger c-di-GMP controls the cell cycle in a similar way as a traffic light works. In the absence of c-di-GMP in the cell, the light shows red.

This indicates that the cell will have to remain in the first phase of the cell cycle. If the c-di-GMP level increases, the light switches to green and the cell enters the next phase. The scientists have investigated what exactly occurs on the molecular level.

c-di-GMP controls an enzyme with two modes of action

The role of this traffic light is played by an enzyme that works in two different ways. “When c-di-GMP is lacking, it blocks the process which leads to replication of the genetic material,” explains Jenal. “However, as soon as c-di-GMP is produced, it binds to the enzyme, thus altering its structure and mode of action. Subsequently, this blockade is lifted and the bacterial chromosomes can be copied.”

This step marks the entry into the next phase of the cell cycle. The varying spatial distribution of the signaling molecule in the dividing mother cell also plays an important role in the behavior of the progeny.

Pathogens use the same signaling network

It is the first time that the researchers have been able to establish a direct connection between the two major regulatory networks of bacterial cells, – the small messenger and important regulatory enzymes called kinases. The insights gained provide an important basis for elucidating the much more complicated c-di-GMP networks of pathogens.

The signaling molecule is involved in virulence, persistence mechanisms and antibiotic resistance of pathogens. For instance, dangerous pathogens causing cholera or pneumonia use c-di-GMP signaling to survive in their human host. As a next step, the researchers want to figure out, whether this molecule acts in these pathogens in the same way as in the model bacterium C. crescentus.

Original paper

Lori C, Ozaki S, Steiner S, Böhm R, Abel S, Dubey BN, Schirmer T, Hiller S, and Jenal U.
Cyclic di-GMP acts as a cell cycle oscillator to drive chromosome replication. Nature; published online 6th May 2015.

Further informations

Prof. Urs Jenal, Biozentrum University of Basel, Tel: +41 61 267 21 35,
E-Mail: urs.jenal@unibas.ch

Weitere Informationen:

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14473.html - Original paper

Christoph Dieffenbacher | Universität Basel
Further information:
http://www.unibas.ch

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>