Synaptic Maintenance and Tenacity
At its most fundamental level, the central nervous system (CNS) may be viewed as a vast network of nerve cells that are interconnected by synapses which are specialized sites of cell-cell contact for the transmission of signals. CNS synapses are minute structures that are often located at enormous distances from the cell’s biosynthetic centers, and whose constituent proteins exhibit remarkable dynamics, such as exchange with extrasynaptic pools and redistribution among neighboring synapses. Yet synapses are widely believed to constitute key loci for modifying the functional properties of such networks, possibly providing the basis for phenomena referred to as "learning and memory". How tenacious are synapses in adhering to their individual structural and functional characteristics? What is the basis for this tenacity? By combining advanced imaging techniques and multielectrode array-based recordings of network activity in primary cultures of rat and mouse neurons, we have started to examine the degree to which synapses maintain their unique properties over many hours to weeks, and the mechanisms that underlie underlying these abilities.