Global identification and characterization of miRNA family members responsive to potassium deprivation in wheat (Triticum aestivum L.)

• Published in: Scientific reports 2020-09, Vol.10 (1), p.15812-15812, Article 15812
• Main Authors: Zhao, Yong, Xu, Ke, Liu, Gaoran, Li, Shanshan, Zhao, Sihang, Liu, Xiaowei, Yang, Xueju, Xiao, Kai
• Format: Article
• Language: English
• Subjects: 631/337; 631/449; Gene Expression Profiling; Gene Expression Regulation, Plant; High-Throughput Nucleotide Sequencing; Humanities and Social Sciences; MicroRNAs - genetics; MicroRNAs - metabolism; multidisciplinary; Nicotiana - genetics; Nicotiana - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Plants, Genetically Modified - genetics; Plants, Genetically Modified - metabolism; Potassium - metabolism; RNA, Plant - analysis; RNA, Plant - genetics; Science; Science (multidisciplinary); Triticum - genetics; Triticum - growth & development; Triticum - metabolism
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-72642-y

Potassium (K) is essential for plant growth and stress responses. MicroRNAs (miRNAs) are involved in adaptation to nutrient deprivation through modulating gene expression. Here, we identified the miRNAs responsive to K deficiency in Triticum aestivum based on high-throughput small RNA sequencing analyses. Eighty-nine miRNAs, including 68 previously reported ones and 21 novel ones, displayed differential expression under K deficiency. In Gene Ontology and Kyoto Encyclopedia and Genome analyses, the putative target genes of the differentially expressed miRNAs were categorized into functional groups associated with ADP-binding activity, secondary metabolic pathways, and biosynthesis and metabolism. Functional characterization of tae-miR408, an miRNA significantly down-regulated under K deficiency, revealed its important role in mediating low-K tolerance. Compared with wild type, transgenic tobacco lines overexpressing tae-miR408 showed significantly improved K uptake, biomass, photosynthesis, and reactive oxygen species scavenging under K deficiency. These results show that distinct miRNAs function in the plant response to K deficiency through regulating target genes involved in energy metabolism and various secondary metabolic pathways. Our findings shed light on the plant response to K deficiency mediated by miRNAs in T. aestivum . Distinct miRNAs, such as tae-miR408, are valuable targets for generating crop varieties with improved K-use efficiency.