Involvement of Plant Micrornas in Abiotic Stress Responses

Crop production is constrained by several biotic and abiotic stresses.Several techniques have been applied by different research groups to unravel themolecular mechanism of tolerance to these stress factors in plants. Recently micro-RNAs have contributed towards understanding the role of micro-RNAs underabiotic stress conditions. Through first reported in animals its abundance in foundin plants even with some difference in biogenesis and mechanism of target generegulation. However, the relationship between micro-RNAs and stress responsesis just beginning to be explored. Micro-RNAs are about 21-24 nucleotide singlestranded non coding RNA often conserved across species suggesting theirevolutionary significance. MiRNAs are either up or down regulated under stressconditions suggesting their involvement in gene expression regulation by posttranscriptional degradation or translational repression in plants. A major categoryof MiRNA target gene consists of transcription factors or other regulatory proteinsthat function in plant development or signal transduction. One our own researchendeavour in this direction revealed the role of MiRNA towards salinity stressresponse in sugarcane. Several researches worldwide is leading to the identificationof thousands of miRNAs, the functional validation of which will help in designingnew strategies for improving tolerance to biotic and abiotic stresses. The currentreview gives the recent status of micro-RNA research towards its role under abioticstress.