Identification and characterization of microRNAs in Biomphalaria tenagophila and comparative analysis of their expression in Schistosoma mansoni-resistant and -susceptible snail populations

Abstract

BackgroundSchistosomiasis is a neglected tropical disease caused by Schistosoma and affects over 240 million people worldwide. One of the most prominent causative agents is Schistosoma mansoni, which develops inside the intermediate host. Biomphalaria tenagophila is the second most important vector of schistosomiasis in Brazil and the Taim population is completely resistant to infection by S. mansoni. ObjectiveThis study aims to identify and characterize B. tenagophila microRNAs (miRNAs) and evaluate their differential expression in S. mansoni-susceptible and -resistant populations of B. tenagophila. MethodsTwo populations of B. tenagophila snails, susceptible and resistant to S. mansoni infection, were used to investigate the small RNA response of these snails after being infected with the parasite. Small RNA sequencing and quantitative real-time PCR were employed to identify and validate differentially expressed miRNAs. Bioinformatics analysis were performed to identify miRNA precursors and mature and evaluate their differential expression. FindingsThe study predicted 173 mature miRNAs and 123 precursors. Among them were six Lophotrochozoa-specific miRNAs, three mollusk-specific miRNAs, and six pre-miRNAs in a cluster. The small RNA sequencing and RT-PCR of B. tenagophila samples allowed assessing the expression patterns of miRNAs. Main conclusionsThe results obtained may support future studies in Biomphalaria spp., generating a global impact on disease control.