The role of synaptotagmins in olfactory processing (B06#)

• Subject Area: Molecular Biology and Physiology of Neurons and Glial Cells
• Term: from 2012 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 154113120

Neurotransmitter release from synaptic vesicles is essential for synaptic transmission between neurons in a circuit. In addition, neuropeptide and neurotrophin release from dense core vesicles, from both pre and post-synaptic sites in neurons, is essential for the modulation of circuit function. Both types of exocytotic events are important for olfactory system function, and for the reliable detection and discrimination of different odors. This sensory system is unique in that olfactory signal processing and odorant discrimination occurs via dendro-dendritic lateral inhibition between granule cells and mitral cells (which receive input from olfactory receptor neurons), before the refined signal is transmitted out of the olfactory bulb to the olfactory cortex. However, the mechanisms of dendritic glutamate release from mitral cells, and of GABA release from granule cell dendrites, are currently unknown. In addition, recent data indicates that neuropeptides exert modulatory effects on these release events to affect olfactory bulb function. The synaptotagmin family of molecules regulates both neurotransmitter and neuropeptide/ neurotrophin release. Interestingly, different syt isoforms are localized to different layers of the olfactory system, suggesting a specialization of neurotransmitter/ neuropeptide release at different levels of olfactory processing. We aim to characterize the localization of different syt isoforms to specific layers, cell types, subcellular sites, and vesicle types in the olfactory bulb, and to determine the function of these syt isoforms in olfactory processing and odor discrimination.

• DFG Programme: Collaborative Research Centres
• Subproject of: SFB 889: Cellular Mechanisms of Sensory Processing
• Applicant Institution: Georg-August-Universität Göttingen
• Project Head: Dr. Camin Dean