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bioRxiv · 10.1101/2022.01.24.477462

Single-molecule nanopore dielectrophoretic trapping of α-Synuclein with lipid membranes

Wu, J.·Yamashita, T.·Hamilton, A. D.·Thompson, S.·Luo, J.
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Abstract

The lipid--Synuclein (-Syn) interaction plays a crucial role in the pathogenesis of Parkinsons disease. Here, we trap -Syn at a conjunction of an -hemolysin (HL) single nanopore-lipid to investigate the folding and unfolding kinetics of -Syn in a lipidic environment. The hybridized -Syn is generated through a reaction between a 5-thiol-modified nucleotide oligo (dC30) and the -Syn mutant (A140C). Owing to an applied voltage, single-molecule hybridized -Syn can be trapped at the single nanopore. The trapping events are associated with dielectrophoretic force. The folding and unfolding events of -Syn can be observed at the pore-membrane junction through interpretation of blockade current amplitudes and dwell time. This can be related to the protein quaternary structure influenced by the -Syn-membrane interaction, allowing further analysis of -Syn conformational dynamics. We studied how disease associated metal ions (Cu2+, Zn2+) modulate folding and unfolding of -Syn at the interface of the membranes and pore, and how -helical peptidomimetics stabilize the helical conformation of -Syn in the presence of a membrane. These studies aid our understanding of the complexity of the interaction of -Syn, lipid membranes and metal ions, and in using peptidomimetics, a new strategy against -Syn toxicity and aggregation is advanced.

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Wu, J., Yamashita, T., Hamilton, A. D., Thompson, S., Luo, J.. 2022-01-24. Single-molecule nanopore dielectrophoretic trapping of α-Synuclein with lipid membranes. https://doi.org/10.1101/2022.01.24.477462

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