Figure 3.

Increased levels of "tailed" acetylcholinesterase (AChE‐T) splice variant in SH‐SY5Y cells with increased tau phosphorylation. Immunodetection of AChE variants in cellular extracts from SH‐SY5Y cells with elevated P‐tau resulting of glycogen synthase kinase‐3β (GSK3β) plus total tau transfection (GSK3β + tau) and control cells transfected with a pCI empty vector (control). Thirty microgram of protein from cell extracts was resolved by electrophoresis and probed with specific primary antibodies raised to: (a) the C‐terminus of the AChE‐T variant; (b) the C‐terminus of “readthrough” acetylcholinesterase (AChE‐R) variant; (c) the extended N‐terminus of AChE (N‐AChE) variants. Representative blots and densitometric quantification of the immunoreactive bands, expressed as percentage (%) relative to immunoreactivity of the control group are shown. For semiquantitative analysis, the levels were normalized to the housekeeping protein GAPDH. (d) Relative mRNA levels of the transcripts for AChE splice variants were analyzed by qRT‐PCR. The specificity of the PCR products was confirmed by dissociation curve analysis. Transcript levels were calculated by the comparative 2^−ΔCt method with respect to GAPDH. Values are means ± SEM from at least of 24 cell wells independent determinations from four independent cell culture experiments. *p <.05 significantly different from the control group (Student's t‐test)