Role of Alpha‐Synuclein and it mutants on Dithiocarbamates Cytotoxicity

Abstract

Mn‐containing dithiocarbamates, such as maneb (MB) and mancozeb (MZ), have been known to increase the toxicity of neurotoxin MPTP on dopaminergic neurons leading to cell death and Parkinson‐like symptoms. Dopamine transporter (DAT), a key protein in MPTP's toxicity, transports the active metabolite (MPP+) into dopaminergic neurons; increasing the cell surface expression of DAT increases uptake of MPTP. Alpha‐synuclein (both wt and A30P & A53T mutants) have been associated with Parkinson's, and are thought to regulate DAT trafficking by interacting with DAT.The aim of this study is elucidate the role of the alpha‐synuclein and its mutants on dithiocarbamate cytotoxicity. HEK cells transfected with DAT and alpha‐synuclein (either wt or mutant) were treated with dithiocarbamates. Lysates were used for co‐immunoprecipitation using anti‐DAT antibody. The precipitated proteins were subjected to Western blot analysis using alpha‐synuclein and DAT antibodies.We report roughly a 30% decrease in the DAT/alpha‐synuclein interaction in the presence of the A53T mutant versus wild‐type, but not in the present of A30P mutant. With dithiocarbamates the interaction of DAT and alpha‐synuclein (wt) was enhanced, with increases ranging from 50% to 200%. Pesticide treated A53T mutants respond more dramatically than A30P mutants in increasing the interaction between the DAT and the alpha‐synuclein.