Scientists of the Research Center caesar in Bonn, an Institute of the Max Planck Society, developed a new biosensor, which allows to measure nanomolar levels of the second messenger cAMP. The sensor makes it possible to study cAMP signaling with high precision, even in subcellular compartments. Using this new biosensor, the scientists of the Minerva Max Planck Research Group “Molecular Physiology“ headed by Dagmar Wachten and of the Department “Molecular Sensory Systems” headed by Benjamin Kaupp revealed how the production of cAMP is regulated in the flagella of sperm cells from mice.
Cells can change the way they grow, move, or develop in response to stimuli from their environment. This information is first detected at the surface of the cell and then translated into an intracellular response by signaling molecules known as “second messengers”. A molecule called cAMP is a well-known second messenger that is involved in many different signaling pathways.
Some cells have hair-like structures called cilia or flagella on their surface, which have been proposed to function as antennae for extracellular stimuli. Cilia are membrane protrusions that come in two different flavors - they can be motile or immotile. A special case of a motile cilium is the flagellum with the most prominent example being the sperm flagellum.
The second messenger cAMP plays an essential role in making motile cilia move, but it is challenging to analyze, how the levels of this molecule change over time in these structures. The levels of cAMP in live cells can only be measured using fluorescent biosensors.
Introducing these biosensors into subcellular compartments is difficult and so far, the sensors have not been sensitive enough to respond to low levels of cAMP. Furthermore, it is difficult to measure cAMP activity inside such tiny structures using these biosensors.
The team of scientists created a new cAMP biosensor that has several unique features. The sensor is based on FRET (Förster resonance energy transfer) technology. FRET is a mechanism describing energy transfer between two light-sensitive molecules.
In the new created biosensor, the amount of energy tranfer depends on the distance and orientation between two light-sensitive molecules. Upon binding to cAMP, a structural rearrangement increases the distance of the two molecules and thereby decreases the amount of energy transferred between them.
Most importantly, the sensor can respond to very low levels of cAMP, making it more sensitive than previous biosensors. The caesar scientists tested this new biosensor in the flagella of sperm cells from mice, which revealed how the production of cAMP is regulated in the flagellum. The new biosensor also showed that different parts of the flagellum can have different cAMP dynamics.
In the future, this new biosensor could be used to study cAMP in other structures and compartments within cells.
Mukherjee, S., Jansen, V., Jikeli ,J. F., Hamzeh, H., Alvarez, L., Dombrowski, M., Balbach, M., Strünker, T., Seifert, R., Kaupp U. B. & Wachten, D. (2016) "A novel biosensor to study cAMP dynamics in cilia and flagella", eLife, DOI: http://dx.doi.org/10.7554/eLife.14052
Dr. Dagmar Wachten
Minerva Max-Planck-Forschungsgruppe "Molekulare Physiologie"
Dr. Jürgen Reifarth | idw - Informationsdienst Wissenschaft
Individual Receptors Caught at Work
19.10.2017 | Julius-Maximilians-Universität Würzburg
Rapid environmental change makes species more vulnerable to extinction
19.10.2017 | Universität Zürich
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
19.10.2017 | Materials Sciences
19.10.2017 | Materials Sciences
19.10.2017 | Physics and Astronomy