Abstract

MicroRNAs (miRNAs) are group of small, non-coding RNAs that play important roles in plant growth, development and stress response. There have been an increasing number of investigations aimed at discovering miRNAs and analyzing their functions in model plants. In this study, we constructed high temperature stress induced small RNA libraries and characterized 26 potential miRNAs belonging to 21 families in French bean. A total of 140 annotated potential targets were found, of which majority were transcription factors (MYB, bHLH, GRF1, bZIP, NAC etc.,) which may play an important role in stress resistance. RT-qPCR and Northern blot analysis revealed differential expressions of candidate miRNAs and their target genes. The observed induction of miRNA expression is correlated with the down regulation of their targets. Investigation of gene ontology linked with targets of miRNAs forecasted their involvement in various biological functions. We anticipate the further studies may offer new avenues in developing stress tolerant variety of French bean.

Key words: miRNA; MYB; quantitative PCR; Transcription factors