Neurotransmitter-mediated signaling is one of the basic forms of communication between neurons and their targets. The release of neurotransmitters from neuronal cells is controlled by the so-called SNARE proteins (soluble N- ethylmaleimide-sensitive fusion protein attachment protein receptor). The SNAREs are multiple proteins that form a large complex that leads to the fusion of neurotransmitter-containing vesicles with cell plasma membranes. In this application, Dr. Yuechueng Liu proposes to dissect the events that involve the assembly and disassembly of the SNARE proteins at the molecular level using engineered fluorescent SNARE proteins. By measurement of fluorescence changes in cells during neurotransmitter release, the interaction of the SNARE proteins can be monitored and studied. This research will provide us with fundamental knowledge regarding how neuronal cells communicate with each other, and it will ultimately help us to understand many normal and abnormal brain functions such as learning and memory, depression, and schizophrenia.