Figure 4
From: RNAi-mediated knock-down of Dab and Numb attenuate Aβ levels via γ-secretase mediated APP processing
Effects of RNAi knock-down of Numb on APP processing and Aβ levels in H4-APP-C99 cells. In H4-APP-C99 cells, Numb siRNA treatment decreases protein levels of Numb, increases protein levels of APP-C99 and decreases Aβ levels. A. APP processing in Western blot analyses. Numb immunoblotting shows reductions in protein levels of Numb in the cells treated with Numb siRNA (columns 3 and 4) as compared to control siRNA (columns 1 and 2). APP-CTFs immunoblotting shows increases in protein levels of APP-C99 in the cells treated with Numb siRNA (columns 3 and 4) as compared to control siRNA (columns 1 and 2). B. Numb protein levels assessed by quantifying Numb in the Western blot. Numb siRNA treatment significantly decreases protein levels of Numb as compared to control siRNA treatment (*p < 0.05), normalized to β-actin. C. APP processing assessed by quantifying ratio of APP-C99 to endogenous FL-APP in the Western blot. Numb siRNA treatment significantly increases ratio of APP-C99 to FL-APP as compared to control siRNA treatment (*p < 0.05), normalized to β-actin. D. APP processing assessed by quantifying ratio of APP-C83 to endogenous FL-APP in the Western blot. Numb siRNA treatment does not significantly increase ratio of APP-C83 to FL-APP as compared to control siRNA treatment (*p < 0.05), normalized to β-actin. E. Effects of RNAi knock-down of Numb on Aβ levels in H4-APP-C99 cells. Numb siRNA treatment decreases Aβ40 levels as compared to control siRNA treatment (*p < 0.05).