A Conserved miR394-Targeted F-Box Gene Positively Regulates Drought Resistance in Foxtail Millet

• Published in: Journal of plant biology = Singmul Hakhoe chi 2021, 64(3), , pp.243-252
• Main Authors: Geng, Zhao, Liu, Jianguang, Li, Dan, Zhao, Guiyuan, Liu, Xu, Dou, Haikuan, Lv, Linxuan, Zhang, Hanshuang, Wang, Yongqiang
• Format: Article
• Language: English
• Subjects: Abscisic acid; Biomedical and Life Sciences; Cereal crops; Cloning; Crops; Drought; Drought resistance; Genomes; Germination; Leaves; Life Sciences; Methyl jasmonate; MicroRNAs; Millet; miRNA; Plant Breeding/Biotechnology; Plant Ecology; Plant Genetics and Genomics; Plant Sciences; Plant Systematics/Taxonomy/Biogeography; Research Article; Rice; RNA ligase; Roles; Roots; Salicylic acid; Seeds; Setaria italica; Transgenic plants; 생물학
• ISSN: 1226-9239; 1867-0725
• DOI: 10.1007/s12374-021-09303-8

One of the oldest crops, foxtail millet ( Setaria italica ), is regarded as a model plant for studying drought tolerance owing to its short life-cycle and small genome size. The miRNA member miR394 plays multifaceted roles in plants. In this study, we identified the Sit-miR394 target gene SiFBP6 using 5′ RLM-RACE (RNA ligase mediated rapid amplification of 5′ cDNA ends). An expression analysis in different tissues showed that Sit-miR394 was highly expressed in leaves and had a lower relative expression in roots, while the target gene SiFBP6 exhibited the opposite expression pattern, being strongly expressed in roots and relatively lowly expressed in leaves. Furthermore, Sit-miR394 was upregulated in foxtail millet under drought-stress conditions and by exogenous methyl jasmonate, ethephon, salicylic acid and abscisic acid treatments. The overexpression of Sit-miR394 in transgenic Arabidopsis thaliana increased its tolerance to drought stress. The germination rates and root lengths were significantly greater compared with the wild-type line, which suggested that Sit-miR394 plays a positive role in responding to drought conditions. Moreover, a transcription analysis indicated that the overexpression of Sit-miR394 affected the expression of a set of stress-related genes, thereby conferring an increased abiotic or biotic stress tolerance to transgenic Arabidopsis . Thus, Sit-miR394 functions in the positive modulation of abiotic or biotic stress tolerance and has potential applications in molecular breeding to enhance stress tolerance in crops.