Computational Identification And Molecular Cloning Of Micro RNA Genes In Tomato (Solanum Lycopersicum)

MicroRNAs (miRNAs) are a newly discovered class of non-protein-coding small RNAs with roughly 22 nucleotide long. Increasing evidence has shown that miRNAs play multiple roles in biological processes, including development, cell proliferation, apoptosis and stress responses. Because the tomato genome sequencing is not finished, little is reported about the experimental or computational identification of conserved miRNAs and their target genes in tomato. In this research, using a computational homology search approach, 24 conserved miRNAs were detected in the Expressed Sequence Tags (EST) and Genomic Survey Sequence (GSS) tomato databases. Following this, 81 potential target genes were predicted by searching the mRNA database. Most of the target mRNAs appeared to be involved in plant growth and development. To validate the prediction of miRNAs in tomato, we performed a poly(A)-tailed RT-PCR based assay of mature miRNA expression and two miRNAs were identified.