title: Preliminary analysis of miRNA pathway in Schistosoma mansoni.
abstract: RNA silencing refers to a series of nuclear and cytoplasmatic processes involved in the post-transcriptional regulation of gene expression or post-transcriptional gene silencing (PTGS), either by sequence-specific mRNA degradation or by translational arrest. The best characterized small RNAs are microRNAs (miRNAs), which predominantly perform gene silencing through post-transcriptional mechanisms. In this work we used bioinformatic approaches to identify the parasitic trematode Schistosoma mansoni sequences that are similar to enzymes involved in the post-transcriptional gene silencing mediated by miRNA pathway. We used amino acid sequences of well-known proteins involved in the miRNA pathway against S. mansoni genome and transcriptome databases identifying a total of 13 putative proteins in the parasite. In addition, the transcript levels of SmDicer1 and SmAgo2/3/4 were identified by qRT-PCR using cercariae, adult worms, eggs and in vitro cultivated schistosomula. Our results showed that the SmDicer1 and SmAgo2/3/4 are differentially expressed during schistosomula development, suggesting that the miRNA pathway is regulated at the transcript level and therefore may control gene expression during the life cycle of S. mansoni.
authors.affiliation: Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Morro do Cruzeiro, 35400-000, Ouro Preto, MG, Brazil. matheusop@yahoo.com.br
authors.forename: Matheus S
authors.initials: MS
authors.lastname: Gomes
authors.forename: Fernanda J
authors.initials: FJ
authors.lastname: Cabral
authors.forename: Liana K
authors.initials: LK
authors.lastname: Jannotti-Passos
authors.forename: Omar
authors.initials: O
authors.lastname: Carvalho
authors.forename: Vanderlei
authors.initials: V
authors.lastname: Rodrigues
authors.forename: Elio H
authors.initials: EH
authors.lastname: Baba
authors.forename: Renata G
authors.initials: RG
authors.lastname: Sá
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019295:Computational Biology / Q000379:methods*; D005786:Gene Expression Regulation; D017238:Genes, Helminth; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008018:Life Cycle Stages; D051379:Mice; D008807:Mice, Inbred BALB C; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D034622:RNA Interference; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D043244:Ribonuclease III / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012550:Schistosoma mansoni / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D015801:Helminth Proteins; D035683:MicroRNAs; D016601:RNA-Binding Proteins; D043244:Ribonuclease III