Fig. 5.

Endogenous β-Syn naturally acts as an inhibitor of hα-Syn aggregation in primary neurons. (A) Immunocytochemistry validates the loss of α- and β-Syn expression in α-Syn–KO, β-Syn–KO, and triple Syn–KO neurons compared to WT neurons. (B) Significantly more β-Syn–KO neurons and triple-KO neurons (one-way ANOVA and Scheffé post hoc analysis) develop inclusions (>1 µm in diameter) compared to non-Tg neurons (mean ± SD, n = 3 independent experiments, 20 neurons per condition). (C) Inclusions formed in β-Syn–KO and triple Syn–KO neurons are pS129–α-Syn–positive. Colocalization was confirmed by assessing regression coefficients (R²). (Scale bars: 20 µm in A and 5 µm in B and C.)