Figure 1. Knockdown of Gα_q inhibits TP receptor-mediated increases in APP and Aβ.

hTP-hAPP cells were transfected with 50 nM of control siRNA or siRNA directed to Gα_q, Gα₁₂, or Gα₁₃ and cultured for 72 h, with IBOP (10 nM) added over the last 48 h. (A) qRT-PCR analysis revealed a reduction in IBOP-induced APP mRNA levels only in cells treated with Gα_q siRNA [R.Q. (relative quantification) values of APP/GAPDH from qPCR are plotted relative to non-IBOP-treated cells without siRNA addition]. (B) Only cells treated with Gα_q siRNA showed reduced APP protein expression, as determined by immunoblot analysis with 5685 antibody [values are relative to non-IBOP-treated cells without siRNA addition, with normalization to α-tubulin]. Statistical analyses consisted of a mixed-effects model, with values representing estimates from the least squares means fit of the mixed procedure from 2–6 independent studies with 1–3 replicates for each treatment/study. Error bars represent SEM; **p < 0.01; ***p < 0.001.