Fig. 2. Effect of IFITM3 on γ-secretase activity for APP cleavage.
(a) IFITM3 KD by siRNA (n=3) in HEK-APPWT cells was confirmed by WB. Scramble siRNA (SC, n=3), a negative control. (b) IFITM3 KD reduces secreted Aβ40 (n=6, ****p<0.0001) and 42 (n=6, ****p<0.0001). Aβ levels were calculated as % of SC. (c) IFITM3 was KO of U138 cells, and empty vector (EV) was used as control. IFITM3 was reintroduced by transient transfection in both EV and KO cell lines. IFITM3 expression was confirmed by WB. (d) Effect of KO and rescue of IFITM3 on γ-secretase activity for Aβ40 (n=3, *p= 0.0249, ****p<0.0001) and 42 (n=3, *p=0.0359, **p=0.0025) cleavage. (e) Comparison IC50 of GSM E2012-BPyne against γ-secretase for Aβ40 (n=6, **p= 0.0017) and Aβ42 (n=6, ns) cleavages in U138 EV and KO cells. All WB images and graphs are representative of three independent experiments (except; e: contains data from 2 experimental replicates of n=3). Graphs are mean ± SD. Ns, not significant, two-sided Student’s t-test (except; d: one-way ANOVA and Fishers LSD test).