Description:

Abstract: Dynamic networks are often signed, i.e. nodes can activate or inhibit other nodes via their connections. The proportion of excitatory and inhibitory connections (E:I balance) is crucial since a dysbalance can lead to functional impairment. Nervous systems are such real-life dynamic networks in which neurons can excite or inhibit other neurons via chemical synapses and E:I dysbalance is observed in e.g. epilepsia and ischemic brain injury. However, experimental research on synaptic polarities is, at least, challenging. The nervous system of the nematode Caenorhabditis elegans is currently the only connectome that has fully been reconstructed and consists of 302 neurons and ~3500 chemical connections (~20.000 individual synapses). We developed an in silico sign prediction method that utilizes gene expression data and made predictions for 70% of ionotropic chemical synapses. With this method we found the E:I ratio to be 3:1 which is similar to what has been found in other neuronal and non-neuronal networks. Ours is the first attempt to provide comprehensive data on synaptic polarities in a complete nervous system. Related publication is available: https://doi.org/10.1371/journal.pcbi.1007974

About the presenter: 

Bánk Fenyves, MD is a PhD-candidate at the Department of Molecular Biology, Semmelweis University (Budapest, Hungary). He has been studying C. elegans for a decade. 

Dr. Bank Fenyves, Semmelweis University

Host: Istvan Kovacs

Keywords: Physics, Astronomy, Complex Systems