Fig. 4: Amyloid-like filament formation of the SOD1 proteins.

a Thioflavin T (ThT) fluorescence intensities representing the filament formation of the C57D/C146D mutant SOD1 (red), C57A/C146A mutant SOD1 (green), and wild-type SOD1 (WT, blue) proteins in the reaction buffer containing 0 mM DTT (A-i), 50 mM DTT (A-ii), and 100 mM DTT (A-iii). The data points are represented by the mean values of six independent experiments. The individual raw datasets are presented in Supplementary Fig. 6a. b Negative-stain transmission electron micrographs of the C57D/C146D mutant SOD1 (left) or wild-type SOD1 (right) proteins. Both proteins were incubated in reaction buffer containing 50 mM DTT for 90 h. The boxes within the micrographs are enlarged in the corners of the micrographs. Scale bars indicate 50 nm.