Computational identification and characterization of miRNAs and their target genes from five cyprinidae fishes

MicroRNAs (miRNAs) are a kind of small single-strand RNA molecules with lengths of 18–25 nt, which do not encode any proteins. They play an essential role in gene expression regulation by binding to their target genes, leading to translational repression or transcript degradation. In this study, 23 miRNAs were predicted from five cyprinidae fishes by using a bioinformatics-based gene search based on blasting ESTs and GSS in NCBI, of which 21 miRNA genes have not been previously reported. To prove their validity, five of the computationally predicted miRNAs were verified by RTPCR, their transcripts were successfully detected, and, 46 potential target genes for these miRNAs were predicted, most target genes encode transcription factors, they are involved in signal transduction, metabolism and development processes.