Researchers demonstrate how some genes evolved from an immune function to an olfactory role in some mammals.
Mammals possess several lines of defense against microbes. One of them is activated when receptors called Fprs, which are present on immune cells, bind to specific molecules that are linked to pathogens. Researchers at the University of Geneva (UNIGE), Switzerland, showed in 2009 that these same receptors were also present in the nose of mice, probably to detect contaminated food or to avoid sick conspecifics. The biologists now describe in the journal PNAS how Fprs have acquired this olfactory role during rodent evolution, moving from the immune system to a neuronal system. This innovation results from two genomic ‘accidents’ that occurred several millions years apart during the evolution of rodents.
Figure legend : Mammals express Fprs in their immune cells (yellow). A first genomic accident led to the expression of an Fpr in olfactory neurons of a rodents’ ancestor (dark blue). This was followed by a second accident that occurred in the mouse lineage (light blue).
Swiss researchers find that the brain is full of multi-dimensional geometrical structures
A team of researchers from the Swiss Blue Brain Project — a group focusing on supercomputer-powered reconstruction of the human brain — have used a classic branch of maths in a completely new way to better understand the structure of our brains.
The brain is a complicated organ, and little is still known about its inner workings, so this new study, which found that the brain is full of multi-dimensional geometrical structures operating in as many as 11 dimensions, is fascinating, to say the least. The neuroscientists behind the study used algebraic topology, which is a branch of mathematics that describes the properties of objects and spaces without the confinements of how they change shape, to conclude that groups of neurons connect into “cliques.” Their work also revealed that the number of neurons in a clique leads to its size as a high-dimensional geometric object.
The annual symposium of the Bertarelli program in translation neuroscience and neuroengineering will take place this year at the Campus Biotech on April 7, 2017.
Swiss and American researchers are developing a technique of unprecedented precision to visualize and manipulate the action of neurotransmitters.
The transmission of information in the brain goes through neurotransmitter molecules which diffuse themselves through the junction zone between two nerve cells called the synapse. In some cases, these molecules can spread into the tissue, thus inundating different types of nerve cells, it is called “neuromodulation”. To better understand the impact of neuromodulators on cerebral circuits and behavior, it is necessary to be able to identify the stimulated neurons and then to follow their activity.
A collaboration between a team from the University of Geneva (UNIGE) and the Max Planck Institute for Neurosciences (MPFI) in Florida has solved this problem with a new technique called iTango, which makes it possible to control in real time the cells subjected to the neuromodulation. iTango is based on an innovative gene expression system based on light, it will allow scientists to better understand the mechanisms of control of the brain circuits involved, for example, in addiction or in certain psychiatric disorders such as schizophrenia. Results are published in Nature Methods. Read More »
The Biaggi de Blasys Award for the best thesis in neuroscience in 2016 went to two LNDS alumni:
Dr. Sebastiano BARISELLI for his thesis “SHANK3 CONTROLS MATURATION OF SOCIAL REWARD CIRCUITS IN THE VTA” defended at the University of Geneva on May 25, 2016.
Dr. Shanaz DIESSLER for her thesis “TOWARDS AN UNDERSTANDING OF SLEEP REGULATION: TWO GENETIC APPROACHES IN THE MOUSE” defended at the University of Lausanne on July 15, 2016.
The human brain has the ability to recognize and process a very wide range of sensory stimuli, from which it builds a mental representation. But do these representations change over time? Can we learn to classify and interpret stimuli more effectively?
Neuroscientists at the University of Geneva (UNIGE) have been trying to answer these questions by studying the olfactory system of mammals. They have succeeded in identifying the complementary role played by two distinct kinds of neurons in processing olfactory information and the different brain re-organization that occurs depending on the context.
After having previously demonstrated the possibility to boost the capacity to distinguish similar smells by regulating the inhibition of certain neural networks, the scientists now explain why the brain has to make use of different sorts of cells to form, maintain and reshape the representations of odors. In fact, it is their very combination that enables us to recognize and distinguish similar smells. Find out more about the research outcomes in the journal Neuron.
Every year 15 million preterm infants are born, and most spend their first weeks in neonatal intensive care units (NICUs). Although essential for the support and survival of these infants, the sensory environment of a NICU is dramatically different from the environment in which term-born infants mature, and thus impacts the development of functional brain organization. Amplifying the importance of this fact, early sensory development is the critical scaffold upon which healthy perceptual, behavioral and cognitive development depends.
In neonates, touch is a building block for interpersonal interactions and sensory-cognitive development. Many NICU treatments used to improve neuro-developmental outcomes rely heavily on touch. Yet, we understand little of how the brains of babies born prematurely and the quality of their early-life tactile experiences (e.g., supportive touch vs. painful tactile events) interact to shape ongoing brain development.
The development of cerebral cortex plays a major role in the evolution of species and in particular for mankind. This is why scientists are studying the emergence of its cellular microstructure with high resolution methods. Neuroscientists at the University of Geneva (UNIGE), Switzerland, have analysed the diversity of cortical neurons – more precisely inhibitory interneurons – during the developmental period surrounding birth. They have discovered the emergence of three main sub-groups of interneurons by decoding the expression of cell-type specific genes as well as their exact, and often unexpected, location in the cortex.
These results, which can be read in Nature Communications, will open the door to a more accurate understanding of the complex cell-type specific mechanisms underlying neuro-developmental disorders such as autism and schizophrenia. This should help researchers in discovering how psychiatric-related genetic disturbances impact the emergence of neuronal sub-types and how to design novel cell-type specific interventions. […] Full article ►
Pfizer Award 2017 – 25 young Swiss researchers were awarded for their outstanding scientific work, including three teams from the HUG and UNIGE. These are two joint HUG/UNIGE teams in clinical research and a UNIGE core research team.
The Pfizer Prize for Research, one of the most prestigious prizes in medicine in Switzerland, has been awarded annually since 1992 by the Pfizer Research Foundation, on the basis of independent scientific commissions.