Neurodegenerative diseases and the influence of particular matter (PM)

For those known neurodegeneration diseases, the aggregation or precipitation of specific protein has been observed inside cells. As for Parkinson’s disease, it has been proposed that aggregated forms of a-synuclein play a crucial role in the pathogenesis of synucleinopathies. The molecular mechanism underlying the pathogenic effects of a-synuclein is still unclear. It has been known that a-Synuclein will aggregate into insoluble form in Lewy bodies and Lewy neurites. a-Synuclein mutations (A30P, E46K, H50Q, G51D and A53T)and copy number variants and upregulated expression have been linked to familiar PD. Unexpected finding from some groups suggested that a-Synuclein can occur physiologically not only as unfolded monomers but is large part as multimers (tetramers), assuming to resist aggregation. They reported that there are a dynamic equilibrium between monomer and tetramer formed a-Synuclein inside cell. The family PD mutation A53T a-Synuclein will cause a decreased tetramers in mouse brain and neuron cell line, M17D. Recently, Zhang et al showed that asparagine endopeptidase (AEP) cleaves human a-Synuclein (N103), triggers its aggregation and escalates its neurotoxicity . Most of experiments were performed will intact cell crosslinking assays, and the products were separated with SDS-PAGE. Even though they design fluorescence microscopy assay (Venus-YFP complementation) to demonstrate the presence of oligomer formed a-Synuclein in the living cell, it is lack of good method to quantify the size of oligomer a-Synuclein. Therefore, we would like to develop fluorescence-based size determination assay in the living cell. The wild type a-Synuclein, five family PD mutations ( A30P, E46K, H50Q, G51D and A53T) and one recently mentioned truncated N103a-Synuclein are chosen to studied in this project.