Effects of SjTeg-20 silencing on caspase activity, tegument destruction, and worm mortality.

<p>(A) Screening of the best siRNA duplex for inhibiting SjTeg-20. Three siRNA duplexes were electroporated into <i>in vitro</i> cultured schistosomes, respectively, and <i>SjTeg-20</i> mRNA levels were determined relative to <i>SjNADH</i> in <i>SjTeg-20</i> siRNA and control siRNA-treated worms at 4 days post electroporation by qRT-PCR. Data illustrate representative results and show the mean and standard errors derived from triplicate experiments. ** <i>P</i> ≤ 0.01. (B) Validation of the <i>SjTeg-20</i> siRNA-132 duplex for silencing SjTeg-20 using western blot analysis. The densitometry results (arbitrary units [AU]) of the Western blot analyzed by Image J were shown as a bar graph. Each bar represents mean±SEM from triplicate experiments. Representative Western blot result was also shown. ** <i>P</i> ≤ 0.01. (C) SjTeg-20 silencing resulted in morphological alterations in the tegument of <i>S</i>. <i>japonicum</i> as determined by SEM. Data are representative results from at least 15 worms investigated in three independent experiments. (D) SjTeg-20 silencing resulted in increased caspase 3/7 activity of cultured worms (28 d) <i>in vitro</i> which were electroporated with <i>SjTeg-20</i> siRNA-132. (E) SjTeg-20 silencing increased worm mortality based on Hoechst 33258 dye staining and microscopic observations. Data are representative results and shown as the mean ± standard error from triplicate experiments. ** <i>P</i> ≤ 0.01 (Student’s t test, <i>SjTeg-20</i> siRNA vs control siRNA).