Identification and characterization of microRNAs and their targets genes in the human parasite Echinococcus canadensis

NATALIA MACCHIAROLI; LUCAS MALDONADO; MARCELA CUCHER; LAURA KAMENETZKY

San Pablo

Conferencia; X-Meeting 2015 - 11th International Conference of the AB3C + Brazilian Symposium of Bioinformatics; 2015

Identification and characterization of microRNAs and their targets genes in the human parasiteEchinococcus canadensisNatalia Macchiaroli1, Lucas Maldonado1, Marcela Cucher1, Laura Kamenetzky1, Mara Rosenzvit11Instituto de Investigaciones en Microbiología y Parasitología Médica, IMPaM (UBA‐CONICET),Facultad de Medicina, Paraguay 2155, Piso 13, CP 1121 Buenos Aires, ArgentinaMicroRNAs (miRNAs), a class of small non‐coding RNAs, are key regulators of gene expression atpost‐transcriptional level and play essential roles in biological processes such as development andmetabolism. MiRNAs silence target mRNAs by binding to complementary sequences in the3´untranslated regions (UTRs) of their target mRNAs. Here, we perform a comprehensive analysisof miRNAs and their targets in the cestode parasite Echinococcus canadensis, one of the causativeagents of the neglected zoonotic disease cystic echinococcosis. Small cDNA libraries from twodevelopmental stages, protoscoleces and cyst walls of E. canadensis were sequenced usingIllumina technology. For miRNA prediction, miRDeep2 core algorithm was used. Differentialexpression analysis of miRNAs between developmental stages was estimated with DESeq andvalidated using poly‐A RT‐qPCR. Furthermore, a high confidence set of 3?UTRs were predicted.Potential mRNA targets of differentially expressed miRNAs were identified using miRandaalgorithm and then filtered using different criteria such as conservation of miRNA binding sites inorthologous mRNAs of other cestode parasites in order to obtain a high confidence set ofpredictions. Functional information of the potential mRNA targets was obtained from GeneDB,wormParasite DataBase and KEEG databases. In this study we used a high‐throughput approach toexpand the miRNA repertoire of E. canadensis. Differential expression analysis showed highlyregulated miRNAs between life cycle stages, suggesting a role in maintaining the features of eachdevelopmental stage or in the regulation of developmental timing. Here we confirmed theremarkable loss of conserved miRNA families in E. canadensis, reflecting their low morphologicalcomplexity and high adaptation to parasitism. We performed the first in‐depth study profiling ofsmall RNAs in the zoonotic parasite E. canadensis. We found that miRNAs are the preponderantsmall RNA silencing molecules, suggesting that these small RNAs could be an essential mechanismof gene regulation in this species. Functional analysis of the differentially expressed miRNAs andtheir potential targets will contribute to elucidate their role in the parasite biology. MiRNAsassociated with parasite development, metabolism, host‐parasite interaction and survivalrepresent potential targets for the development of new therapeutic interventions.