Brain function requires the proper networking and communication between neurons. Improper development and maintenance of neuronal function leads to neurological abnormalities. As such, mechanisms underlying physiological to pathological processes in the brain are not clear. Currently, the laboratory of Dr. Thomas C. S?dhof has allowed me to expand my knowledge in basic events of synaptic transmission to clinically associated problems in Alzheimer's disease. We have identified an essential family of adaptor proteins named Mints that have been implicated in coupling synaptic functions such as targeting of proteins to nerve terminals, and neurotransmission, to the regulation of amyloid precursor protein (APP) processing relating to Alzheimer's disease. To ascertain Mints function directly, we have generated mice lacking individual Mint proteins (isoforms 1-3), or all possible combination of Mint family members. We can now directly study: (1) membrane protein targeting by surface biotinylation of cell membranes, and morphologically examine the expression and cellular distribution of proteins that Mints interact with; (2) functionally examine synaptic transmission by using hippocampal slice electrophysiological recordings, and optical recording techniques of cultured neurons to look at kinetics of synaptic vesicles. We will characterize the structural dynamic of synaptic junctions by electron microscopy, and E-PTA staining to quantify morphological parameter of synapses. To explore the significance of Mint and APP processing, we have generated mice deficient of Mints which carry a transgene that coexpresses mutant APP, and presenilin 1. We will study the pathogenic events leading to disease state by examining age-dependent APP proteolysis and amyloid beta deposition by combining morphological and biochemical techniques. These studies will not only clarify the function of Mints in targeting, and synaptic transmission, but will broaden our understanding in the biology of Mints and. APP in Alzheimer's disease. My long-term goal is to pursue my understanding of molecular mechanisms underlying neuronal plasticity, and neurodegenerative diseases integrating the tools and conceptual approaches that I have learned and gained over my past graduate and postdoctoral training. This award will allow me to have a transition period during which I can expand my knowledge and technical foundations to become an independent principal investigator. ? ? ?
