Alpha-synuclein (aSyn) is a cytosolic 140 amino acids protein and maintaining its cellular level is pivotal to preventing neuronal cell death. In health, aSyn is enriched in the presynaptic terminal and known to interact with the VAMP2 protein responsible for neurotransmission, although the outcomes in neurotransmission are elusive. On the other hand, in Parkinson’s disease patients, aSyn and its aggregate which is composed with organellar membranes and biomolecules are found in the soma and overall neurons. Indeed, emerging evidence suggests the secretion of aSyn aggregates depends on late endosomal/lysosomal VAMP7, which implies a possible aSyn-VAMP7 interaction. Several model systems have brought an invaluable understanding of aSyn and aggregates, yet none of them satisfy to be interpreted in cellulo context due to their extreme artificial condition. Altogether, with my recent publications and preliminary data, I establish hypotheses: i) organelle-specific lipid types and distribution define the aSyn aggregate, ii) VAMP7 interacts with aSyn, and iii) aSyn and aggregates distinctly impact neurotransmission and secretion. Accordingly, in this interdisciplinary project, I will 1) recreate each organellar membrane-dependent aSyn aggregate and systemically compare the physicochemical properties, 2) molecular dissect the aSyn-interacting domain of VAMP7, and 3) characterize the impact of aSyn and aggregates in neurotransmission and secretion by recapitulating the plasma membrane environment in great detail in my high-end 3D-printed membrane setup. Finally, I will 4) validate the outcomes in standard model membranes and bioengineered bacterial and eukaryotic cells.