Impact of Phosphorylation on the Physiological Form of Human alpha-Synuclein in Aqueous Solution


de Bruyn E, Dorn AE, Rossetti G, Fernandez C, Outeiro TF, Schulz JB, Carloni P




bioRxiv 2023.03.10.531864.


Serine 129 can be phosphorylated in pathological inclusions formed by the intrinsically disordered protein human α-synuclein (AS), a key player in Parkinson’s disease and other synucleinopathies. Here, molecular simulations provide insight into the structural ensemble of phosphorylated AS. The simulations suggest that phosphorylation does not impact the structural content of the physiological AS conformational ensemble in aqueous solution, as the phosphate group is mostly solvated. The hydrophobic region of AS contains β-hairpin structures, which may increase the propensity of the protein to undergo amyloid formation, as seen in the non-physiological (non-acetylated) form of the protein in a recent molecular simulation study. Our findings are consistent with existing experimental data, with the caveat of the observed limitations of the force field for the phosphorylated moiety.