Gender associated differential gene expression in Schistosoma mansoni adult worms

The complex molecular systems involved in the process of sex-differentiation and fertility in Schistosoma mansoni have not yet been completely described. Using a 4608-element cDNA microarray, we have now determined 90 and 139 genes with significantly (q-value ≤ 0.06) higher expression levels in adult males and females, respectively. Eight out of eleven selected transcripts had their differential expression levels validated by Real-Time RT-PCR. One of these transcripts was extended by RT-PCR and was shown to span the intronic region between exons 9 to 11 of the S. mansoni CA150 gene, a transcriptional cofactor known in humans to interact with both RNA polymerase II and the spliceosome complex. The longer transcript probably represents a novel isoform of S. mansoni CA150. Additionally, we obtained full-length sequences for 3 other isoforms of the SmCA150 gene, coding for proteins of different lengths and domain compositions. Semi-quantitative RT-PCR showed different expression ratios among these isoforms between male and female. Due to the role of CA150 in RNA transcription and processing, we hypothesize that these differential expression events may be important in the generation and maintenance of the different phenotypes between male and female. Keywords: comparative gender gene expression Three separate samples from males and three from female were analyzed. For each sample, materials from 3 perfusions performed at different dates were pooled, and male and female parasites were separated manually. Two biological replicate sample were prepared with the same procedure, each using material from 3 independent perfusions. One technical replicate from one of the samples was obtained for each gender.