Identification of miRNAs and evaluation of candidate genes expression profile associated with drought stress in barley

Abstract

To identify miRNAs and assess the expression of genes involved in drought stress tolerance, leaf and root ESTs were analyzed in barley. To this end, the EGassembler bioinformatics service and IDEG6 were used for the pre-processing and identify differentially expressed genes among EST libraries, respectively. Furthermore, root contigs were analyzed by C-mii software for miRNAs identification. The expression profile of two drought tolerance candidate genes was studied, using Real time-PCR in a 2 (Nimruz and Spontaneum) × 2 (control and 50% FC) factorial experiment in a completely randomized design with 3 replications. Results of this study showed that N-butyl-N-methylpiperidinium (Pip1;4) and a non-specific lipid transport protein (nsLTP) were found to express differently under drought stress. The expression level of barley HvPip1;4 (HvPiP1;4) and non-specific lipid transport (HvnsLTP) genes increased by 95.98 and 54.53 fold after 72 h of drought stress, respectively. There was a significant difference (P < .05) between two genotypes with respect to the expression level of candidate genes. Nimruz cultivar had a higher expression level for both candidate genes. Comparison analysis of miRNAs showed that miR2102 had a differential expression between non-stressed and drought stress libraries in barley root tissue. Furthermore, HvPiP1;4 and HvnsLTP were miR6201and miR5052 target genes.