CROSSTALK OF CONSERVATION OF SEQUENCES OF miRNAs AND ENZYMATIC MACHINERY OF miRNAs PRODUCTION IN AMPULLARIIDAE

BACKGROUND: The Ampullariidae family of molluscs is an emerging model for evolutionary studies due to its high diversity, ancient history and wide geographic distribution. miRNAs are essential for the development of the organism, as they help and act in the control of gene expression. The analysis of miRNAs in molluscs, especially in the family Ampullariidae, is especially important due to the low representativeness of analyzed species and the possibility of analyzing the conservation of miRNAs among ampullariids species. OBJECTIVE: Identification and characterization of miRNAs (precursors and matures) and their processing pathway genes. METHODS: Computational prediction and characterization of miRNAs and genes involved in the miRNA pathway were performed using public database of Lanistes nyassanus, Marisa cornuarietis, Pomacea canaliculata and Pomacea maculata. The in silico analysis was performed using a robust algorithm to identify and characterize miRNAs and their precursors in genome of ampullariids species. To search for the putative proteins involved in the miRNA biogenesis the putative proteomes from 4 Ampullariids species and Blastp tool were used. Characterization of conserved protein domains was performed using the PFAM and CDD. Phylogenetic analyzes were performed for the ampullariids miRNA precursors and their orthologs and also for the putative ampullariids proteins involved in the miRNA pathway and their orthologs using MEGA program. FINDINGS: 141 pre-miRNAs and 162 mature miRNAs were identified in the genome of L. nyassanus, 279 pre-miRNAs and 297 mature miRNAs in the genome of M. cornuarietis, 269 pre-miRNAs and 296 mature miRNAs in the genome of P. canaliculata and 299 pre-miRNAs and 316 mature miRNAs in the genome of P. maculata. We identified and characterized 24 putative key proteins involved in the miRNA pathway including Argonaute, DICER, DROSHA and EXPORTIN protein families in the predicted proteome of the 4 ampullariids. The data obtained in this work will support studies of phylogeny, population divergence, speciation and patterns of diversity in the Ampullariidae Family. MAIN CONCLUSIONS: The searching for novel miRNAs and their processing pathway genes in 4 species of ampullariids was able to predict new structures expanding the study of miRNAs in molluscs and in Ampullariidae family, as well as open an avenue to study the roles of miRNAs in the organisms.