Zoltan Nusser博士のセミナー(2010年9月1日)
Contents
Date/Time: September 1st(Wed), 2010, 15:00-16:00
Place: 2nd floor Seminar room, FBS Annex Bldg.,Suita Campus
Professor Zoltan Nusser
(Institute of Experimental Medicine,Hungarian Academy of Sciences, Budapest, Hungary)
Molecular and cellular architecture of neuronal circuits
Abstract
The main olfactory bulb (MOB) is the first processing station of the olfactory pathway, where the axon terminals of sensory neurons establish excitatory synapses with the dendrites of mitral and tufted (M/T) cell. In turn, M/T cells project to higher olfactory areas, such as the anterior olfactory nucleus and the piriform cortex. In the MOB the activity of the glutamatergic M/T cells is controlled by several types of GABAergic interneurons, including the well known granule and periglomerular cells. Our group discovered the heterogeneity of an additional GABAergic interneuron type, the so called deep short-axon cells (dSACs), and revealed three distinct subpopulations (Eyre et al., J. Neurosci., 2008). In the first half of my presentation, I will overview our results demonstrating the functional and morphological diversity of dSACs and will demonstrate novel intra- and extra-bulbar projections by dSAC subtypes. Distinct molecular expression profiles of different dSAC subtypes will be also demonstrated, suggesting not only different roles in the MOB circuit, but forming the foundation of future subtype-specific genetic modifications. In the second half of my presentation, I will summarize our recent results regarding the diversity in the cell surface distribution of voltage-gated ion channels. High resolution light- and electron microscopic immunolocalization techniques revealed the cellular domain-, subcellular compartment- and distance-dependent distribution of HCN1 in pyramidal cell apical dendrites (Lorincz et al., Nat. Neurosci., 2002). We have also revealed a cell-to-cell heterogeneity in the voltage-gated K+ and Na+ channel content of the axon initial segments (Lorincz & Nusser, J. Neurosci., 2008). We have identified that the main dendritic Nav subunit is Nav1.6 in hippocampal pyramidal cell and determined the density of Nav1.6 in nodes of Ranvier, AIS, somata, proximal and distal dendrites (Lorincz & Nusser, Science, 2010).
