Quantification of Conserved MicroRNA in Plants and Validation of New Targets

Abstract

MicroRNAs (miRNAs) are approximately 20–24 nucleotide-long, posttranscriptionally regulatory RNAs. These arise from end nucleolytic processing of hairpin precursors. The plants perform transcriptional regulation by short interfering RNAs (siRNAs). The distinctive feature of miRNAs primarily lies in their biogenesis. The siRNA is processed from long double-stranded RNA while the miRNA is processed from single-stranded hairpins. The siRNA also has its role in transcriptional regulation instead of posttranscriptional regulation. The conserved miRNAs and their corresponding target genes are commonly found in all or most of the plant species. The highly conserved miRNA families are evolutionarily conserved across all major lineages of plants and play specific functions in a variety of physiological processes in plant species. These are rather important as they control the expression of important transcription factors by either cleaving or by translational suppression. The transcriptional factors control or regulate the expression of multiple downstream target genes by either activation or suppression. Thus, different regulation patterns of these conserved miRNAs imply complicated transcriptional and posttranscriptional regulation that determine the growth and development processes. The advantage in plant miRNA analysis lies in the positional nucleotidal preferences.