Figure 3
From: RNAi-mediated knock-down of Dab and Numb attenuate Aβ levels via γ-secretase mediated APP processing
Effects of RNAi knock-down of Dab on APP processing and Aβ levels in H4-APP-C99 cells. In H4-APP-C99 cells, Dab siRNA treatment decreases protein levels of Dab, increases protein levels of APP-C83 and APP-C99, and decreases Aβ levels. A. APP processing in Western blot analyses. Dab immunoblotting shows reductions in protein levels of Dab in the cells treated with Dab siRNA (columns 3 to 5) as compared to the cells treated with control siRNA (columns 1 and 2). APP-CTFs immunoblotting shows increases in protein levels of APP-C99 and APP-C83 in the cells treated with Dab siRNA (columns 3 to 5) as compared to control siRNA (columns 1 and 2). The blot showing the band of APP-C83 only is the same blot with less exposure time in developing the film. B. Dab protein levels assessed by quantifying Dab in the Western blot. Dab siRNA treatment significantly decreases protein levels of Dab 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. Dab 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. Dab siRNA treatment significantly increases 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 Dab on Aβ levels in H4-APP-C99 cells. Dab siRNA treatment decreases Aβ40 levels as compared to control siRNA treatment (*p < 0.05).