Neuronal Signalling Mechanisms

BIOGRAPHY

ACADEMIC POSITIONS:
• Professor, Department of Neuroscience and Pharmacology, Faculty of Health Science, University of Copenhagen
• Research Group Leader at the Max Planck Institute for Biophysical Chemistry

EDUCATION:
• MSc 1996 in Biology, Copenhagen University, Denmark
• PhD 1999, Copenhagen University, Denmark
• 2000-2005 scientific assistant (postdoc) at the Max Planck Institute for Biophysical Chemistry, Göttingen
• 2006: Habilitation (Physiology); Faculty of Human Medicine, University of Göttingen

RESEARCH INERESTS:
The release of neurotransmitter happens by exocytosis of transmitter-filled vesicles. Both the high speed of this release process and the tight coupling to the intracellular calcium concentration is critical for normal synaptic transmission in the brain. We are interested in unraveling the molecular specializations behind both properties. Our model systems are adrenal chromaffin cells and cultured hippocampal neurons, where secretion can be monitored using fast electrophysiological (patch clamp) and electrochemical (amperometry) techniques. In order to manipulate presynaptic proteins we take advantage of cells isolated from knock-out mice, where a specific protein is removed, combined with overexpression using viral vectors (Semliki Forest Virus, Adenovirus and Lentivirus). The expression of different protein isoforms, or mutated protein, in knock-out cells is used to assay the involvement of proteins in neurotransmitter release.

The major focus of our interest is the SNARE complex, the synaptotagmins and Munc18 proteins. The SNARE complex consists of SNAP-25, syntaxin and synaptobrevin, which is formed between the vesicle and plasma membrane during fusion. The synaptotagmins are C2-domain containing proteins, that can bind to calcium, phospholipids and SNAREs. They are usually assumed to be calcium-sensors for release. The Munc18 proteins bind to syntaxin and is necessary for docking vesicles to the plasma membrane.