Contribution of astrocytic networks to neurotransmission

• Applicant: Dr. Ulrike Pannasch
• Subject Area: Molecular Biology and Physiology of Neurons and Glial Cells
• Term: from 2007 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 52240806

If neuronal plasticity depends on synaptic activity, the mechanisms responsible for synaptic efficacy are not yet well understood. Recent data suggest an active participation of astrocytes in central functions by dynamic interactions with neurons through their calcium signaling. However the contribution of astrocytes may not only result from individual cells, but also from cellular networks, as they express numerous gap junctions. Thus the goal of this project is to determine whether the connectivity and calcium signaling of astrocytic networks participate in neuronal transmission and plasticity in the hippocampus. The specific aims will determine: 1) How astrocytic networks are organized in the hippocampus and does a plasticity of these networks, dependent on neuronal activity, exist? 2) If astrocytic network organization contributes to neuronal activity and plasticity? 3) What are the astrocytic mechanisms of neuronal modulation? As a major technical limit to the study of neuroglial interactions is to act selectively on astrocytes, targeted pharmacological and molecular tools will be used, such as photolysis of encaged molecules, RNA interference (RNAi) and knockout (KO) mice. Moreover, an interdisciplinary approach combining molecular biology, physiology and mathematical modeling will be adopted in a collaborative effort. The proposed research should provide a better understanding of neuronal transmission and plasticity by identifying new mechanisms of neuroglial interactions. This should reinforce the emerging concept of an active contribution of astrocytes to information processing.

• DFG Programme: Research Fellowships
• International Connection: France
• Host: Dr. Christian Giaume