SLC6A4 and Parkinson disease: α-synuclein, a protein mainly known for its implication in Parkinson’s disease, binds SERT through direct protein-protein interactions via the non-Aβ-amyloid component domain of the α-synuclein protein and promotes SERT internalization, accounting for reduced 5-HT uptake (Wersinger et al., 2006; Wersinger and Sidhu, 2009).