Gender and stage-specific expression of SmDia compared to PDI.

<p>Semi-quantitative RT-PCR analysis (A), densitometric quantification (B), and real-time PCR analysis (C). RT-PCR and qPCR experiments were performed with total RNA from adult worms (females or males) and free-living larval stages (miracidia and cercariae). A: Using SmDia gene-specific primers (SIV5′/SIV3′), RT-PCR products of the expected size of 0.6 kb were obtained from each template, males (Ma), females (Fe), cercariae (Ce), or miracidia (Mi). For control, RNA from mixed worm pools (mixed-sex adult worms and larvae) was used without initial cDNA synthesis (RT⁻). As an additional negative control, PCR was done without any template (H₂O). In the reactions for quantification, primers against the constitutively transcribed protein disulfide-isomerase gene (PDI, 33) were used. B: Result of the densitometric quantification using the PDI RT-PCR products for normalization (n = 1). C: qPCR results, again taking PDI as reference (n = 3).