Transcriptomic Analysis Reveals the Temporal and Spatial Changes in Physiological Process and Gene Expression in Common Buckwheat (Fagopyrum esculentum Moench) Grown under Drought Stress

Abstract

Common buckwheat is a traditional alternative crop that originated from the northwest of China and is widely cultivated worldwide. However, common buckwheat is highly sensitive to drought stress, especially at the seedling stage, and the molecular mechanisms underlying the response to drought stress still remain elusive. In this study, we analyzed the stress phenotypes of buckwheat seedlings under drought condition. The results showed the wrinkled cotyledon due to the decrease of relative water content (RWC) in response to the increased activity of antioxidant enzymes. Transcriptomic analysis was further performed to analyze the regulation patterns of stress-responding genes in common buckwheat cotyledons and roots under drought stress conditions. Characterizations of the differentially expressed genes (DEGs) revealed differential regulation of genes involved in the photosynthesis and oxidoreductase activity in cotyledon, and that they were highly related to the post-transcriptional modification and metabolic process in root. There were 180 drought-inducible transcription factors identified in both cotyledons and roots of the common buckwheat. Our analysis not only identified the drought responsive DEGs and indicated their possible roles in stress adaption, but also primarily studied the molecular mechanisms regulating the drought stress response in common buckwheat.

Transcriptomics and Metabolomics Reveal Purine and Phenylpropanoid Metabolism Response to Drought Stress in Dendrobium sinense, an Endemic Orchid Species in Hainan Island

“…PAL, C4H, and 4CL are key genes in the early stages of lignin and flavonoid biosynthesis (Martens and Mithöfer, 2005). In Fagopyrum esculentum Moench, lignin increases cell wall thickness to prevent water loss and improve drought resistance (Hou et al, 2019). In our study, we found that coumaric acid, coniferol, (E)-p-coumaric acid, and 4-hydroxy-3-methoxy cinnamaldehyde were upregulated in DSB vs. DSC, and five genes related to lignin were also identified.…”

“…In addition, most flavonoids were significantly upregulated in DSB vs. DSC even though we did not identify DEGs associated with flavonoid biosynthesis. However, previous research has shown that genes related to flavonoid biosynthesis were upregulated in buckwheat under drought stress (Hou et al, 2019). It is also suspected that flavonoids have antioxidant properties (Sarker and Oba, 2018).…”

Physiological and Molecular Characterization of Crop Resistance to Abiotic Stresses

“…The irruption of transcriptomics, metabolomics, high-throughput DNA sequencing and high-density microarrays in the analysis of plants' responses to stress have brought new insights and allowed a better understanding on plants reactions to stressful conditions [21]. The stress-responding genes and their regulation pattern under drought were analyzed in common buckwheat cotyledons and roots [22] and female panicles in maize [23], and under salinity in roots and leaves of pomegranate [24].…”

Comparative transcriptome analysis of genes involved in two peanut varieties under drought stress

“…At present, RNA-Sequencing (RNA-Seq) can provide increasing amount of information on differentially expressed genes, transcript structures, new transcripts and isomers, RNA alternative splicing and allele-speci c expression etc [57]. RNA-Seq has been successfully applied to cuckoo, Yerba Mate and cotton [1,10,21], as well as many crop plants such as lentils, buckwheat and millet [23,32,64], to analyze their molecular mechanisms of drought resistance.…”