The rescuing effect of <i>dZip1</i> RNAi on Aβ appears not mediated by affecting Aβ42 nor NEP or IDE expression in the Aβ42 flies.

<p>(A) shows a representative of sqRT-PCR analysis of Aβ42 expression in brains of 20-day-old flies. No Aβ42 expression was detected in brains of <i>elav-Gal4>+/+</i>flies. <i>dZip1</i> RNAi or OE did not significantly influence the expression level of Aβ42 compared to control <i>elav-Gal4>UAS-Aβ42</i> flies. <i>rp49</i> was used as the loading control. (B) Aβ42 expression in brains of 20-day-old flies was determined by qRT-PCR. Statistic analysis showed no significant differences among <i>elav-Gal4>UAS-Aβ42</i>, <i>elav-Gal4>UAS-Aβ42/UAS-dZip1OE</i>, <i>elav-Gal4>UAS-Aβ42/UAS-dZip1 RNAi 1#</i>, and <i>elav-Gal4>UAS-Aβ42</i>/<i>UAS-dZip1 RNAi 2#</i>. <i>t</i>-test, P>0.05 (in comparison with <i>elav-Gal4>UAS-Aβ42</i> flies). n = 3 biological repeats. (C)–(F) shows <i>Drosophila NEP1</i>, <i>NEP2</i>, <i>NEP3</i> and <i>IDE</i> expression in brains of 30 day old flies. All the four degrading enzymes shows higher expression level in fly brains without Aβ42 expression than that with Aβ42 expression. <i>dZip1</i> RNAi did not significantly influence NEP or IDE expression in Aβ42 flies compared to the control Aβ42 flies, while <i>dZip1</i> OE shows a trend of reducing NEP or IDE expression level, but only statistically significant for NEP2. The relative Aβ42, NEP1-3 and IDE expression levels against <i>rp49</i> were from three independent biological replicates and plotted with SEM (error bars).