Macromolecular crowding enhances GSK-3β phosphorylated Tau_244–441 fibrillization.

<p>Filament formation of GSK-3β phosphorylated Tau_244–441 in the absence and in the presence of Ficoll 70 (A and C) and dextran 70 (B and D), respectively, monitored by ThT fluorescence (A and B) and turbidity (C and D). The crowding agent concentrations were 0 (open square), 100 g/l (solid circle), 200 g/l (solid triangle), and 300 g/l (inverted solid triangle), respectively. The empirical Hill equation was fitted to the data and the solid lines represented the best fit. The final concentration of human Tau fragment was 12 µM. The assays were carried out at 37°C. (E) SDS-PAGE profiles of non-phosphorylated and GSK-3β phosphorylated Tau_244–441 fragments. Lane 1, molecular weight SDS calibration kit protein standards. Lane 2 represents non-phosphorylated Tau_244–441 and lane 3 represents GSK-3β phosphorylated Tau_244–441. Proteins in the gel were visualized by a Coomassie Brilliant Blue R staining.