Advances in study of plant miRNAs under stressed environmental conditions

Biotic and abiotic stresses influence plant growth and cause great loss to crop yield. In the long course of evo-lution, plants have developed intricate biological mechanism to resist stressed conditions. Under various stressed conditions, not only the protein-coding genes, but also the non-protein-coding genes were induced for response. More and more re-searches showed that the transcripts of these non-protein-coding genes played important role in regulation of gene expres-sion. miRNA is one of the groups in these no-coding regulatory small RNAs. Recent findings showed that in order to resist the biotic and abiotic stresses, expression of microRNA (miRNA) genes will be induced and their transcripts (miRNAs) can regulate gene expression by guiding target mRNA cleavage or translation inhibition. This paper focused on the advances of plant miRNAs research in stressed conditions, especially induced expression of miRNA and target gene regulation and its role on adaptation under stressed conditions. Then, the methods of miRNA researches in stressed environments are dis-cussed.