Project description:Melatonin is a well-known agent that plays multiple roles in animals. Its possible function in plants is less clear. In the present study, we tested the effect of melatonin (N-acetyl-5-methoxytryptamine) on soybean growth and development. Both spraying of leaves and seed-coating with melatonin significantly promoted soybean growth as judged from leaf size and plant height. This enhancement was also observed in soybean production and their fatty acid content. Melatonin increased pod number, seed number and seed weight. However, the 100-seed weight was not influenced by melatonin application. Melatonin also improved soybean tolerance to salt and drought stresses. Transcriptome analysis revealed that melatonin up-regulated the expression of many genes and alleviated the inhibitory effects of salt stress on gene expressions. Further detailed analysis of the affected pathways documents that melatonin likely achieved its promotional roles in soybean through enhancement of genes involved in cell division, photosynthesis, carbohydrate metabolism, fatty acid biosynthesis and ascorbate metabolism. Our results demonstrate that melatonin has significant potential for improving of soybean growth and seed production. Further study should uncover more about the molecular mechanisms of melatoninM-bM-^@M-^Ys function in soybeans and other crops. Four different treatments were chosen, water, salt, 100M-BM-5M melatonin and salt plus 100M-BM-5M melatonin. The comparison of salt/melatonin-treated sample versus water-treated sample reveals salt or melatonin induced transcriptome changes. The comparison of melatonin plus salt treated sample versus salt-treated sample reveals melatonin induced changes when salt exists.
Project description:Most physiological and molecular mechanisms of salinity stress are researched based on salt shock conditions. However, salt shock doesn’t occur in agricultural practice or natural ecosystem. In the fields, salts accumulate gradually through high salt or sodium irrigation water and poor managements that allow ground water to rise to soil surface. Therefore, it is more reasonable to research salinity stress in a mild way (stepwise salt addition). The objective of this study is to select marker genes to differentiate between salt shock (Phase 0) and salt stress (Phase 1). Three replicates were used for all RNA-Seq experiments conducted on control, Phase 0 and Phase 1 samples in Arabidopsis thaliana. Phase 0 samples (rosette leaves) were harvested 1 hour later from 105 mM NaCl salt shock treatment; Phase 1 samples (rosette leaves) were harvested 2 days later after reaching 90 mM NaCl by a stepwise addition (15 mM NaCl per day).
Project description:Melatonin plays a potential role in multiple plant developmental processes and stress response. However, there are no reports regarding exogenous melatonin promoting rice seed germination under salinity and nor about the underlying molecular mechanisms at genome-wide. Here, we revealed that exogenous application of melatonin conferred roles in promoting rice seed germination under salinity. The putative molecular mechanisms of exogenous melatonin in promoting rice seed germination under high salinity were further investigated through metabolomic and transcriptomic analyses. The results state clearly that the phytohormone contents were reprogrammed, the activities of SOD, CAT, POD were enhanced, and the total antioxidant capacity was activated under salinity by exogenous melatonin. Additionally, melatonin-pre-treated seeds exhibited higher concentrations of glycosides than non-treated seeds under salinity. Furthermore, exogenous melatonin alleviated the accumulation of fatty acids induced by salinity. Genome-wide transcriptomic profiling identified 7160 transcripts that were differentially expressed in NaCl, MT100 and control. Pathway and GO term enrichment analysis revealed that genes involved in the response to oxidative stress, hormone metabolism, heme building, mitochondrion, tricarboxylic acid transformation were altered after melatonin pre-treatment under salinity. This study provides the first evidence of the protective roles of exogenous melatonin in increasing rice seed germination under salt stress, mainly via activation of antioxidants and modulation of metabolic homeostasis.
Project description:Melatonin is a well-known agent that plays multiple roles in animals. Its possible function in plants is less clear. In the present study, we tested the effect of melatonin (N-acetyl-5-methoxytryptamine) on soybean growth and development. Both spraying of leaves and seed-coating with melatonin significantly promoted soybean growth as judged from leaf size and plant height. This enhancement was also observed in soybean production and their fatty acid content. Melatonin increased pod number, seed number and seed weight. However, the 100-seed weight was not influenced by melatonin application. Melatonin also improved soybean tolerance to salt and drought stresses. Transcriptome analysis revealed that melatonin up-regulated the expression of many genes and alleviated the inhibitory effects of salt stress on gene expressions. Further detailed analysis of the affected pathways documents that melatonin likely achieved its promotional roles in soybean through enhancement of genes involved in cell division, photosynthesis, carbohydrate metabolism, fatty acid biosynthesis and ascorbate metabolism. Our results demonstrate that melatonin has significant potential for improving of soybean growth and seed production. Further study should uncover more about the molecular mechanisms of melatonin’s function in soybeans and other crops.
Project description:Our study identified long term salt stress treatment to induce symptoms similar to developmental senescence. In order to identify possible crosstalk components shared between developmental and salt-triggered senescence. We first obtained the expression profile of Arabidopsis leaves under the condition of salt-induced senescence (4 days) and then compared it with the transcriptome of developmental leaf senescence.
Project description:Grapevine rootstock 1616C shoots were sterilized and cultured on Murashige & Skoog (MS) medium containing 2% sucrose (w/v). Plantlets were grown in a growth chamber with a 16-h light/8-h dark cycle for 10 weeks at 25 °C. Plantlets with 4–5 leaves were chosen for use in stress treatments. Experiments were conducted with treatment groups: The control (C, without any chemical treatment), TM (treated with 5 μg mL-1 tunicamycin (TM)) and salt (treated with 400 mM NaCl). Microarray analysis was performed and we investigated transcript profiles in leaves of the salt-tolerant grapevine rootstock 1616C under salt- and ER-stress at 6 and 24 hours
Project description:The global emergence of soil salinization poses a serious challenge to many countries and regions. γ-Aminobutyric acid (GABA) is involved in systemic regulation of plant adaptation to salt stress, but the underling molecular and metabolic mechanism still remains largely unknown. The elevated endogenous GABA level by exogenous application of GABA could significantly improve salt tolerance in creeping bentgrass with the enhancement of antioxidant capacity, photosynthetic characteristics, osmotic adjustment (OA), and water use efficiency. GABA strongly upregulated transcript levels of AsPPa2, AsATPaB2, AsNHX2/4/6, and AsSOS1/20 in roots involved in enhanced capacity of Na+ compartmentalization and mitigation of Na+ toxicity in cytosol. Significant downregulation of AsHKT1/4 expression could be induced by GABA in leaves in relation to maintenance of significantly lower Na+ accumulation and higher K+/Na+ ratio. GABA-depressed aquaporins (AQPs) expression and accumulation induced declines in stomatal conductance and transpiration, thereby reducing water loss in leaves during salt stress. For metabolic regulation, GABA primarily enhanced sugars and amino acids accumulation and metabolism largely contributing to improved salt tolerance through maintaining OA and metabolic homeostasis. Other major pathways could be responsible for GABA-induced salt tolerance including increases in antioxidant defense, heat shock proteins, dehydrins, and myo-inositol accumulation in leaves. Integrative analyses of molecular, protein, metabolic, and physiological changes reveal systemic function of GABA on regulating ions, water, and metabolic homeostasis in non-halophytic creeping bentgrass under salt stress.
Project description:Transcriptional profiling of Arabidopsis rossette leaves comparing WT Col-0 with a transgenic line overexpressing AhERF or AhDOF genes from Amaranthus hypochondriacus under different conditions. Three-condition experiment of WT vs AhERF OE plant leaves. The analyzed conditions were: normal growth conditions, 5 days of water stress (no irrigation) and 24 hrs of recovery after watering water-stressed plants. Besides, a two-condition experiment where WT vs AhDOF OE plant leaves were compared. The experimental conditions were: normal growth conditions and plants watered with 40mL of 400mM NaCl solution for three straight days to produce salt stress.