GSE162539
Identification of microRNAs in response to low potassium stress in the shoots of Tibetan wild barley and cultivated barley [miRNA-seq]
Soil potassium deficiency has become a global problem in agricultural production, seriously restricting crops productions and agricultural sustainable development. Identification of the microRNAs and understanding their functions in response to low K stress will be helpful for developing crop varieties with low K tolerance. Our previous study identified a low K tolerant accession XZ153 from Tibetan wild barley. In this study, small RNA and degradome analysis were performed on two barley genotypes differing in low K tolerance (XZ153, tolerant; ZD9, sensitive) to identify the miRNAs and their targets responding to low K stress. A total of 1108 miRNAs were detected in shoots of XZ153, and ZD9 at 2 d and 7 d after low K stress, and their targets were identified through bioinformatics prediction and degradome analysis. We identified 65 differentially expressed miRNAs responding to low K stress. The results also showed that miR164c, miR169h and miR395a modules could mediate TCA cycle, glycolysis pathway and pentose phosphate pathway responding to low K stress. The osa-miR166g-3p and ghr-miR482b may act as the regulators in Ca2+ signaling pathway in response to low K stress. The methionine salvage cycle involved in ethylene biosynthesis process mediated by miR396c-3p and osa-miR171e-5p might be also involved in responding to low K stress. Some miRNAs, including miR160a, miR396c and miR169h modules, which participated in photosynthesis regulation under low K stress, differed between the two barley genotypes. In conclusion, these exclusively expressed miRNAs and their targets play the crucial roles in low K tolerance. Overall design: A total of 24 shoot samples (two genotypes × two potassium conditions × two time periods × three replications) were harvested for further RNA isolation and library construction.