Conference Proceeding

Role of MicroRNA Inabiotic Stress Tolerance in Field Crops

Mr. Rahul Singh, Dr Dharamsheela

Major threats to plant productivity are abiotic stresses like drought, soil toxicity, climate change etc. and biotic threats. Advancement in molecular biology demonstrated the involvement of microRNAs (miRNAs) in regulating essential plant metabolic processes at the post-transcriptional level against abiotic stress. miRNAs are single-stranded non coding RNAs sized usually between 20 and 24 nucleotides (nt) that serve as gene regulators in a wide range of plant as well as other organisms. miRNA were first discovered in the nematode Caenorhabditis elegans in 1993 at which time they were considered as small temporal RNAs while Plant miRNAs were identified 10 years after animal miRNAs discovery. miRNAs are transcribed from genes, but the transcripts are not translated into proteins. Plant miRNAs are derived by processing of their RNA precursors. Such precursors are occasionally transcribed from an intron or exon of a protein coding region, but most precursors are transcribed from the intergenic regions of genomes. This microRNA responds to variable expression due to different level of stress in same plant species. Identification of different miRNA and their tissue specific targets involves various bioinformatics tools followed by experimental approaches Some of the target bioinformatics tools used for miRNA target prediction are psRNATarget, TAPIR, miRTourand miRTarBase, the experimentally validated microRNA-target interactions database While the expression levels of the target mRNAs can be monitored by real-time PCR, the target cutting site can be mapped by 5′-Rapid Amplification of cDNA Ends (RACE). Different type of microRNA which shows variable expression in different abiotic stress in various field crops has been identified. In 2004, 20 miRNAs were first identified in rice from a rice cDNA library and their predicted potential target genes were known to be involved in transport (miR-4, miR-15), disease resistance (miR-10), transcription (miR-4), metabolism (miR-5) etc. Maize is the second most important and has also been used in research as a model plant has Five miRNAs including miR156, miR160, miR166] miR167, miR169 families involved in maize development, growth, and responses to biotic stress were firstly described and characterized with their potential genes. In wheat using sequencing which led to the discovery of 58 wheat miRNAs. About 100 miRNAs were identified for the first time in barley using deep Sequencing. Interest of miRNAs in soybean began in 2008, when for the first time, 55 families of miRNAs of which 20 conserved and 35 new miRNAs were identified. A total of 47 miRNAs belonging to 13 miRNA families (miR160, miR172, miR319 etc.) were first identified in Cowpea. About 446 sorghum miRNAs are available. Hundreds of miRNAs have been identified and characterized in cotton. The role of miRNAs in response to salinity stress was also investigated in cotton and found that 17 cotton miRNAs which belong to eight families were identified and it was found that more miRNAs responded to variable expression against salinity treatment. This technology is new and emerging technology can enhance the production and productivity of agricultural crops, so there is need to more extensive research work in this field.

Published: 08 November 2017


© 2017 Mr. Rahul Singh. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.