Figure 2.

DNA promotes PSM fibrillation via direct association. (A) Crystal structure of PSMα3 fiber (PDB: 5I55) with electric potentials of charge residues projected on surface model. The electric potentials were calculated using Chimera software. (B) Fluorescence staining of PSMα3-DNA complexes using nucleic acid dye BOBO-3 iodine (red) and Thioflavin T, which only binds to fibrillar amyloid structures. Scale bar: 3μm.(C) Fibrillization of synthetic PSMα3 with or without CpG DNA was monitored by Thioflavin T fluorescence and reported as relative fluorescent units (RFU). Mean and SEM graphed; significance was calculated using One-way ANOVA with Tukey’s multiple comparisons test (*, P < 0.05).