The Institute for Structural Neurobiology is focused on the dynamic changes in neuronal structures during development and on adaptive processes in adulthood.
We study the cellular and molecular mechanisms governing migration of cortical and hippocampal neurons from their sites of origin to their destinations. The extracellular matrix molecule Reelin, synthesized by Cajal-Retzius cells in the marginal zone of the cerebral cortex, is a major player in this process. We recently discovered that Reelin induces branching of the leading processes of migrating neurons as they reach the marginal zone. These branches and Reelin-induced cofilin phosphorylation anchor the leading processes to the marginal zone allowing for directed neuronal migration towards the cortical plate. Reelin deficiency results in servere alterations of neuronal migration.
In electrophysiological and electron microscopic studies we analyze the functional and structural changes at synapses, the contacts between nerve cells (neurons). Synaptic plasticity is assumed to play an important role during learning and memory processes. In our fine-structural studies we use high-pressure freezing for electron microscopy, which enables us to study subtle, transient structural changes at synapses associated with functional changes. High-pressure freezing immobilizes tissue samples within approximately 50 ms without the use of aldehyde fixatives known to denaturate proteins. By combining high-pressure freezing with immunogold labeling for electron microscopy we analyze the molecular composition of identified synapses in the central nervous system. With this approach we aim at understanding the structural and molecular changes associated with synaptic plasticity and adaptive neuronal mechanisms such as learning and memory.
Professor Peter Jonas
(Institute of Science and Technology Austria)
Professor Joachim Herz
Department of Molecular Genetics
University of Texas Southwestern Medical Center
Dallas, TX 75390, USA