Synapsin 1, encoded by the SYN1 gene is a member of the larger synapsin family. The synapsins are phosphoproteins found on the surface of synaptic vessicles. This localization is useful, as synapsin antibodies can selectively label pre-synaptic nerve terminals.
While the sole reason for the choice of synapsin as a starting point for this project was "it was the first thing that popped into my head," it turned out to be an interesting choice. Due to the high conservation of synapsin across species, its orthologs may provide an interesting method for tracing the evolutionary history of organisms.