Effect of phosphorylation on tau isoform polymerization. Each isoform (A) 2N3R, (B) 2N4R, (C) 1N3R, (D) 1N4R, (E) 0N3R, and (F) 0N4R was polymerized with 75 μM ARA after phosphorylation by GSK-3β (+p) or without phosphorylation (-p). Reactions were measured by LLS (black bars and left y-axis) and ThS fluorescence (open bars and right y-axis). All LLS data is background subtracted with AIP for -p and AIPp for +p values respectively. Data is an average of 3 trials ± SEM.