Dynamic Expression of Long Non-Coding RNAs Throughout Parasite Sexual and Neural Maturation in Schistosoma Japonicum

Abstract

<i>Schistosoma japonicum</i> is a flatworm that causes schistosomiasis, a neglected tropical disease. <i>S. japonicum</i> RNA-Seq analyses has been previously reported in the literature on females and males obtained during sexual maturation from 14 to 28 days post-infection in mouse, resulting in the identification of protein-coding genes and pathways, whose expression levels were related to sexual development. However, this work did not include an analysis of long non-coding RNAs (lncRNAs). Here, we applied a pipeline to identify and annotate lncRNAs in 66 <i>S. japonicum</i> RNA-Seq publicly available libraries, from different life-cycle stages. We also performed co-expression analyses to find stage-specific lncRNAs possibly related to sexual maturation. We identified 12,291 <i>S. japonicum</i> expressed lncRNAs. Sequence similarity search and synteny conservation indicated that some 14% of <i>S. japonicum</i> intergenic lncRNAs have synteny conservation with <i>S. mansoni</i> intergenic lncRNAs. Co-expression analyses showed that lncRNAs and protein-coding genes in <i>S. japonicum</i> males and females have a dynamic co-expression throughout sexual maturation, showing differential expression between the sexes; the protein-coding genes were related to the nervous system development, lipid and drug metabolism, and overall parasite survival. Co-expression pattern suggests that lncRNAs possibly regulate these processes or are regulated by the same activation program as that of protein-coding genes.