French Austrian Joint Project: Austrian Science Fund (FWF) – Agence Nationale de la Recherche (ANR)
Title: Optical control of synaptic function via adhesion molecules
Project acronym: SyntheSyn
Project reference: I 3600-B27
Principal investigator: Johann Danzl
International project partner, principal investigator: Dr. Olivier Thoumine,
Interdisciplinary Institute for Neuroscience, Bordeaux, France.
Philipp Velicky (Postdoc)
Caroline Kreuzinger (Lab Technician)
Which role do synaptic adhesion molecules play in synaptic connections?
Signals in our brains are sent from one neuron to another via specialized connections, the synapses. The message itself is sent through chemicals called neurotransmitters, which are released by the pre-synaptic neuron and sensed through receptors on the post-synaptic neuron. But the pre- and post-synaptic neurons are also structurally connected through so-called adhesion molecules. These neuronal adhesion molecules, such as neurexins on the pre-synaptic neuron and neuroligins on the post-synaptic neuron, play important roles in wiring, sculpting and maintaining synaptic connections. But how do synaptic adhesion molecules control the formation of synapses? The groups of Johann Danzl at IST Austria and of Olivier Thoumine at the Interdisciplinary Institute for Neuroscience in Bordeaux (F) investigate this question by putting the adhesion molecules under light control, helping to understand synaptic development and function.
In the project, we will use optogenetically controlled synaptic adhesion molecules, which can be switched on and off with light at exactly defined time points. In this way, we can follow the formation of synapses in living neurons as adhesion molecules are switched from an inactive configuration into their active state. The Thoumine lab is specialized in neuronal adhesion proteins, with expertise in single molecule imaging, computation and electrophysiology to study adhesion molecules and their dynamics at the single-molecule level. The Danzl lab at IST Austria has expertise in super-resolution imaging of neuronal structures, providing much higher resolution than conventional light microscopy. This allows us to image the fine structural features of neuronal cells and synapses and to elucidate the arrangement of synaptic adhesion molecules. Bringing the expertise of these labs together, the project will enable the scientists to dynamically and quantitatively describe and regulate adhesion protein clustering and function at synapses.