Living organisms are dependent on being able to adjust the water content in their cells. This is achieved by regulating the flow of water through the cell membrane. Water is ‘turned on’ and ‘turned off’ by membrane proteins that function as water conduits and are called aquaporins. In the new issue of Nature, Professor Per Kjellbom and Associate Professor Urban Johanson, plant biochemists at Lund University, Sweden, describe how this takes place. The discovery is not only a breakthrough for pure science. It may also pave the way for a new type of drug and for new cosmetic products.
Peter Agre discovered the first aquaporin in 1992 in red blood cells and was awarded the 2003 Nobel Prize. Since then, 13 variants of aquaporin have been found in animals and humans and 35 in plants. There are thousands of these aquaporins in every cell membrane. Aquaporins contain a conduit that is so tiny that only a single water molecule at a time can pass through it. But this traffic can be lively indeed. In one second, several billion water molecules can get through. The direction of this water flow is contingent on the osmotic pressure. The water moves in a direction away from a low and toward a high concentration of salt and nutritional substances. But the conduit isn’t always open. The Lund scientists have found out how it opens and closes. This was done in collaboration with a team at Chalmers University of Technology in Göteborg, Sweden, under the direction of Richard Neutze, and with Emad Tajkhorshid at the University of Illinois.
“We have used yeast fungi to produce aquaporins,” says Per Kjellbom. With our method we can produce sufficient amounts of pure aquaporins to obtain the crystals needed for our analyses. It turns out that with the technology we used to crystallize aquaporins they were in the closed position. Previously it had only been possible to produce open aquaporins. This gave us an opportunity to compare open and closed aquaporins and to understand how this opening and closing works at the molecular level.
Göran Frankel | alfa
Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital
New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
12.12.2017 | Physics and Astronomy
12.12.2017 | Earth Sciences
12.12.2017 | Power and Electrical Engineering