Figure 1

Quantitative immunofluorescence detection of reductions in 12E8 tau and total tau protein levels using MAPT siRNA. Shown in A is reduction of both pS262 tau and total tau levels using an siRNA directed at the tau transcript (all splice variants). Using this siRNA, pS262 tau and total tau levels are reduced to 45% and 54% of control values, respectively, following 4 days of transfection with siRNA. pS262 tau is visualized in red. Total tau is in green. Blue staining represents DAPI stained nuclei. Note that significant total tau expression remains following siRNA treatment, likely resulting from the extremely high constitutive levels of tau expression in this cell line. Shown in B is secondary quantitation of the MAPT siRNA effects on 12E8 and total tau using western analyses. Results support the immunofluorescence quantitation shown in A. Representative images are shown. Percent control numbers (± SD) in A represent the average of three independent assays. Westerns in B were performed in triplicate. NS refers to the non-silencing siRNA control.