Plant miRNAs and abiotic stress responses.

MicroRNAs (miRNAs) are endogenous approximate 22 nucleotide (nt) small non-coding regulatory RNAs that play important roles in plants by targeting mRNAs for cleavage or translational repression. Plant miRNAs were described 10 years later than animal miRNAs did; there are some differences between them in terms of biogenesis and mechanism of function. Furthermore, plant miRNAs have been shown to be involved in various stress responses, such as oxidative, mineral nutrient deficiency, dehydration, and even mechanical stimulus. In this review, we focus on the current understanding of biogenesis and regulatory mechanisms of plant miRNAs. We also highlight specific examples of miRNAs, which are important regulators for plant abiotic stress responses.