Biology
A glimpse inside the control centres of cell communication
Numerous processes taking place within our body, such as sight, smell or taste, are accomplished by an important family of sensors on cell surfaces, which are known as G protein-coupled receptors (GPCR). Researchers have now compared the hitherto known structures of GPCRs and discovered a stabilising framework of fine struts that is characteristic for the architecture of the entire GPCR family. Knowledge about this constructional feature, which has been conserved over the course of evolution, can be of significant assistance in the development of new pharmaceuticals.
How stabilised cell fibres prevent cancer cell division
Anti-cancer drugs are used under the heading of Chemotherapeutics to prevent cells from dividing. Because the cells in a growing tumour divide more frequently than others, tumour cells are damaged more severely. Scientists at the Paul Scherrer Institute and the ETH Zurich have now clarified the exact mechanism of action of one class of these drugs. The data acquired is so accurate, that targeted drugs could now be developed that are even better suited to fulfil their task.
The evolutionary origins of our pretty smile
Until recently, it was not obvious whether the earliest vertebrates (animals with a backbone) which had jawbones already possessed teeth or not. Now, an international research team has shown that the jaws of the prehistoric fish Compagopiscis already had teeth. This means that teeth appeared at the same evolutionary time as jaws à or at least shortly afterwards. The leaders of this project were scientists from the University of Bristol, England, who carried out their decisive experiments at the SLS at PSI.
Nobelpreiswürdig: G-Protein-gekoppelte Rezeptoren
Der Nobelpreis für Chemie geht in diesem Jahr an Robert J. Lefkowitz und Brian K. Kobilka. Sie haben herausgefunden, wie eine Familie von Rezeptoren funktioniert, die man G-Protein-gekoppelte Rezeptoren (GPCR) nennt. Auch am PSI leisten Wissenschaftler Beiträge auf diesem Forschungsgebiet.This news release is only available in German.
Alzheimer plaques in 3D
Researchers have succeeded in generating detailed three-dimensional images of the spatial distribution of amyloid plaques in the brains of mice afflicted with Alzheimer’s disease. The new technique used in the investigations provides an extremely precise research tool for a better understanding of the disease. In the future, scientists hope that it will also provide the basis for a new and reliable diagnosis method. The results were achieved within a joint project of two research teams à one from the Paul Scherrer Institute (PSI) and ETH Zurich, the other from the École Polytechnique Fédérale de Lausanne (EPFL).
How the body distinguishes between self and non-self – important structures explained
Like a shredder, the immunoproteasome cuts down proteins into peptides that are subsequently presented on the cellular surface. The immune system can distinguish between self and non-self peptides and selectively kills cells that present non-self peptides at their surface. In autoimmune diseases, this mechanism is deregulated. However, inhibition of the immunoproteasome may alleviate disease symptoms and progression. With the help of measurements taken at the Paul Scherer Institute, scientists have now succeeded in determining the first structure of an immunoproteasome.
Fossile Vorläufer der ersten Tiere
Einzellige Organismen, die vor über einer halben Milliarde Jahre gelebt haben und deren Fossilien in China gefunden wurden, sind wohl die unmittelbaren Vorläufer der frühesten Tiere. Die amöbenartigen Einzeller haben sich in einer Weise in zwei, vier, acht usw. Zellen geteilt, wie es heute tierische (und menschliche) Embryonen tun. Die Forscher glauben, dass diese Organismen einem der ersten Schritte vom Einzeller zum Vielzeller in der Entwicklung richtiger Tiere entsprechen.This news release is only available in German.
Wenn die Datenleitung in die Zelle versagt
Lebende Zellen empfangen dauernd Informationen von aussen, die über Rezeptoren in das Zellinnere weitergeleitet werden. Genetisch bedingte Fehler in solchen Rezeptoren sind der Grund für zahlreiche Erbkrankheiten darunter verschiedene hormonelle Funktionsstörungen oder Nachtblindheit. Forschern des Paul Scherrer Instituts ist es nun erstmals gelungen, die exakte Struktur eines solchen fehlerhaften Rezeptors aufzuklären.This news release is only available in German.
Nanoforscher untersuchen Karies
Forscher der Universität Basel und des Paul Scherrer Instituts konnten im Nanomassstab zeigen, wie sich Karies auf die menschlichen Zähne auswirkt. Ihre Studie eröffnet neue Perspektiven für die Behandlung von Zahnschäden, bei denen heute nur der Griff zum Bohrer bleibt. Die Forschungsergebnisse wurden in der Fachzeitschrift «Nanomedicine» veröffentlicht.This news release is only available in German.
Plants create a water reserve in the soil
An international research team has now demonstrated in experiments at the Paul Scherrer Institute that the soil in the vicinity of roots contains more water that that further away. Apparently, plants create a small water reserve that helps to tide them over through short periods of drought. These results were obtained from experiments carried out with the benefit of neutron tomography.
Getting inside the mind (and up the nose) of our ancient ancestors
Reorganisation of the brain and sense organs could be the key to the evolutionary success of vertebrates, one of the great puzzles in evolutionary biology, according to a paper by an international team of researchers, published today in Nature. The study claims to have solved this scientific riddle by studying the brain of a 400 million year old fossilized jawless fish à an evolutionary intermediate between the living jawless and jawed vertebrates.
X-ray methods help to understand brain disorders better
An international team of researchers has developed a new method for making detailed X-ray images of brain tissue, which has been used to make the myelin sheaths of nerve fibres visible. Damage to these protective sheaths can lead to various disorders, such as multiple sclerosis. The facility for creating these images of the protective sheaths of nerve cells is being operated at the Swiss Light Source (SLS), at the Paul Scherrer Institute.
The basic structures of sight deciphered
At the beginning of the process of sight, light interacts with a protein molecule called Rhodopsin. This molecule contains the actual light sensor that is stimulated by the incoming light and changes its form, in order to trigger the rest of the process. Researchers have now managed to determine the exact structure of the Rhodopsin molecule in its short-lived, excited state. From this, they have obtained a precise picture of the first step of the process of sight.
Dem Rätsel der Centriolen-Bildung auf der Spur
In menschlichen Zellen finden sich stammesgeschichtlich sehr alte Funktionseinheiten, die als Centriolen bezeichnet werden. Ein Forscherteam vom PSI und der ETH Lausanne hat nun erstmals ein Modell für die Bildung der Centriolen vorgestellt. Das erstaunende Ergebnis ist, dass die Neuner-Symmetrie des Centriols durch die Fähigkeit eines einzelnen Proteins sich selbst zu organisieren zustande kommt.This news release is only available in French and German.
Understanding the nanomachines of life
Ribosomes are the protein factories of the living cell and themselves very complex biomolecules. Now, a French research group has for the first time determined the structure of the ribosome in a eukaryotic cell à a complex cell containing a cell nucleus. An important part of the experiments was performed with synchrotron light at the Swiss Light Source SLS of the Paul Scherrer Institute.
Effizienter Gentransfer nun auch in Säugerzellen möglich
Wissenschaftler am Paul Scherrer Institut entwickelten ein neues Verfahren, das auch zur Entwicklung von neuen Medikamenten genutzt werden kann.Die Gentechnik ist aus der modernen Biologie nicht mehr wegzudenken. Sie liefert Werkzeuge, mit denen Forscher Gene aus dem Erbgut von Zellen herausschneiden, verändern und einfügen können. Die stabile Einführung mehrerer Gene in Säugetierzellen gilt zwar als Schlüsseltechnologie, die verfügbaren Methoden waren bislang aber äusserst ineffizient. Wissenschaftler am PSI haben nun eine neuartige Technik entwickelt.This news release is only available in German.
High-resolution method for computed nano-tomography developed
High-resolution method for computed nano-tomography developedA novel nano-tomography method developed by a team of researchers from the Technische Universität München, the Paul Scherrer Institute and the ETH Zurich opens the door to computed tomography examinations of minute structures at nanometer resolutions. The new method makes possible, for example, three-dimensional internal imaging of fragile bone structures.
New X-ray technique distinguishes between that which previously looked the same
Images generated using the phase-contrast technique allow one to distinguish between tissue types such as muscle, cartilage, tendons or soft-tissue tumours that look virtually identical in conventional X-ray images. Researchers at the Paul Scherrer Institute and the Chinese Academy of Science have further developed the technique to make it easier to use in the future. This could help in the detection of tumours or in the identification of hazardous objects in luggage.
Proton pump generates energy from food and oxygen
A central feature of any living organism is that food reacts with oxygen and, in the process, energy is released and made available for a variety of reactions within the organism. Using investigations performed at the Swiss Light Source, SLS, researchers have now been able to explain a crucial part of this process at a molecular level.
Attacking the lifeline of tumour cells
Researchers at Biomedicum Helsinki, Finland, and the Paul Scherrer Institute (PSI) in Villigen, Switzerland, have determined the crystal structure of the ligand-binding domain of a vascular endothelial growth factor (VEGF) receptor in complex with one of its ligands (VEGF-C).