MicroRNAs (miRNAs) are small RNA molecules (~20 nucleotides) that post-transcriptionally regulate the expression of endogenous genes, shaping the transcriptome and protein production. In general, miRNAs are highly conserved in the genome of eukaryotes and considered important elements in many biological processes during development, such as cell growth, differentiation and death. The large diversity of miRNAs identified is somewhat restricted to a few species and only a fraction of the predicted miRNAs targets has been functionally characterized. In this sense, the use of next generation sequencing technology coupled with gene expression analysis by RT-qPCR enable both the identification of the microRNome and the experimental validation of miRNA gene targets in a species. The Nile Tilapia, Oreochromis niloticus, can be considered an excellent biological model for miRNAs investigation in vertebrates due to its economic importance and fully sequenced genome. To produce a functional annotation of the tilapia microRNome, this project aims to (i) organize the sequence data of expressed miRNAs, (ii) develop an open-access database of Nile tilapia miRNAs, (iii) integrate information of this database with other relevant databases, (iv) create hypotheses about physiologically relevant actions of these miRNAs by analyzing the miRNAs clusters induced by their similar expression profiles in different types of tissue (white muscle, red muscle, gonads, brain etc..) and different stages of development, (v) predict the miRNAs targets, and finally, (vi) determine the chromosomal location of expressed miRNAs on the 22 chromosomes of tilapia in order to build genomic maps of microRNA genes.
News published in Agência FAPESP Newsletter about the scholarship: