Repression of α-synuclein expression and toxicity by microRNA-7

Alpha-Synuclein is a key protein in Parkinson's disease (PD) because it accumulates as fibrillar aggregates in pathologic hallmark features in affected brain regions, most notably in nigral dopaminergic neurons. Intraneuronal levels of this protein appear critical in mediating its toxicity, because multiplication of its gene locus leads to autosomal dominant PD, and transgenic animal models overexpressing human alpha-synuclein manifest impaired function or decreased survival of dopaminergic neurons. Here, we show that microRNA-7 (miR-7), which is expressed mainly in neurons, represses alpha-synuclein protein levels through the 3'-untranslated region (UTR) of alpha-synuclein mRNA. Importantly, miR-7-induced…