Project description:Xerophytes play an active role in preventing soil denudation and desertification in arid and semi-arid areas. Peganum harmala L. (Zygophyllaceae family), a seasonally growing, poisonous and drought-tolerant plant, is widely distributed in the Xinjiang Uygur Autonomous Region and used as a traditional herbal medicine as well as, in winter, a fodder source. Previous research has focused on the pharmacological activity of isolated compounds and stress responses to growth environments. However, the metabolic profile of P. harmala and variations in its metabolites, including medicinally active and stress resistance components, have not been illustrated during different growth stages. Here, we collected plant samples in May, August, October and December. We determined the metabolic composition of methanol extracts using NMR spectroscopy, and comparisons of four growth stages were accomplished by applying statistical analysis. The results showed that vasicine, choline and sucrose were significantly elevated in samples harvested in May. Significantly higher amounts of betaine, lysine, 4-hydroxyisoleucine and proline were found in samples collected in August than in samples collected in other months, and the concentrations of phosphorylcholine, glucose, acetic acid and vasicinone were highest in December. The relationships between differential biomarkers and plant physiological states affected by diverse growth environmental factors were discussed. Our result deepened the understanding of metabolic mechanisms in plant development and confirmed the advantage of using NMR-based metabolomic treatments in quality evaluation when P. harmala is used for different purposes.
Project description:Effects of cold plasma treatment on seed germination, seedling growth, antioxidant enzymes, lipid peroxidation levels and osmotic-adjustment products of oilseed rape under drought stress were investigated in a drought-sensitive (Zhongshuang 7) and drought-tolerant cultivar (Zhongshuang 11). Results showed that, under drought stress, cold plasma treatment significantly improved the germination rate by 6.25% in Zhongshuang 7, and 4.44% in Zhongshuang 11. Seedling growth characteristics, including shoot and root dry weights, shoot and root lengths, and lateral root number, significantly increased after cold plasma treatment. The apparent contact angle was reduced by 30.38% in Zhongshuang 7 and 16.91% in Zhongshuang 11. Cold plasma treatment markedly raised superoxide dismutase and catalase activities by 17.71% and 16.52% in Zhongshuang 7, and by 13.00% and 13.21% in Zhongshuang 11. Moreover, cold plasma treatment significantly increased the soluble sugar and protein contents, but reduced the malondialdehyde content in seedlings. Our results suggested that cold plasma treatment improved oilseed rape drought tolerance by improving antioxidant enzyme activities, increasing osmotic-adjustment products, and reducing lipid peroxidation, especially in the drought-sensitive cultivar (Zhongshuang 7). Thus, cold plasma treatment can be used in an ameliorative way to improve germination and protect oilseed rape seedlings against damage caused by drought stress.
Project description:Drought stress is one of the most environmental abiotic stresses affecting seed germination and crop growth. In the present study, the genetic characteristics of seed germination under drought stress in a Brassica napus double haploid population were analyzed. Five germination-related indexes, including germination percentage (GP), root length (RL), shoot length (SL), fresh weight (FW), and root-to-shoot length ratio (R/S) under control and drought stress, were calculated, and the drought stress index (DSI), including DSI-GP, DSI-RL, DSI-SL, DSI-FW, and DSI-R/S, was determined using the quantitative trait loci (QTLs) analysis based on high-density genetic linkage map. The phenotypic analysis indicated that the R/S is an effective morphological trait in the determination of drought tolerance in the seedling stage. Thirty-nine identified QTLs were observed for these traits and then integrated into 36 consensus QTLs, in which 18 QTLs were found to affect the DSI of four traits (GP, RL, SL, and R/S). Based on the co-linearity between genetic and physical maps of B. napus, 256 candidate genes were detected, and 128 genes have single-nucleotidepolymorphisms/insertion-deletion (SNP/InDel) variations between two parents, some of which were associated with the drought stress tolerance (for example, BnaC03g32780D, BnaC03g37030D, and BnaC09g27300D). The present results laid insights into drought tolerance and its genetic bases in B. napus.
Project description:Peganum harmala is a valuable wild plant that grows and survives under adverse conditions and produces pharmaceutical alkaloid metabolites. Using different assemblers to develop a transcriptome improves the quality of assembled transcriptome. In this study, a concrete and accurate method for detecting stress-responsive transcripts by comparing stress-related gene ontology (GO) terms and public domains was designed. An integrated transcriptome for P. harmala including 42 656 coding sequences was created by merging de novo assembled transcriptomes. Around 35 000 transcripts were annotated with more than 90% resemblance to three closely related species of Citrus, which confirmed the robustness of the assembled transcriptome; 4853 stress-responsive transcripts were identified. CYP82 involved in alkaloid biosynthesis showed a higher number of transcripts in P. harmala than in other plants, indicating its diverse alkaloid biosynthesis attributes. Transcription factors (TFs) and regulatory elements with 3887 transcripts comprised 9% of the transcriptome. Among the TFs of the integrated transcriptome, cystein2/histidine2 (C2H2) and WD40 repeat families were the most abundant. The Kyoto Encyclopedia of Genes and Genomes (KEGG) MAPK (mitogen-activated protein kinase) signaling map and the plant hormone signal transduction map showed the highest assigned genes to these pathways, suggesting their potential stress resistance. The P. harmala whole-transcriptome survey provides important resources and paves the way for functional and comparative genomic studies on this plant to discover stress-tolerance-related markers and response mechanisms in stress physiology, phytochemistry, ecology, biodiversity, and evolution. P. harmala can be a potential model for studying adverse environmental cues and metabolite biosynthesis and a major source for the production of various alkaloids.
Project description:BackgroundPuccinellia tenuiflora is the most saline-alkali tolerant plant in the Songnen Plain, one of the three largest soda saline-alkali lands worldwide. Here, we investigated the physicochemical properties of saline-alkali soils from the Songnen Plain and sequenced the transcriptomes of germinated P. tenuiflora seedlings under long-term treatment (from seed soaking) with saline-alkali soil extracts.ResultsWe found that the soils from Songnen Plain were reasonably rich in salts and alkali; moreover, the soils were severely deficient in nitrogen [N], phosphorus [P], potassium [K] and several other mineral elements. This finding demonstrated that P. tenuiflora can survive from not only high saline-alkali stress but also a lack of essential mineral elements. To explore the saline-alkali tolerance mechanism, transcriptional analyses of P. tenuiflora plants treated with water extracts from the saline-alkali soils was performed. Interestingly, unigenes involved in the uptake of N, P, K and the micronutrients were found to be significantly upregulated, which indicated the existence of an efficient nutrition-uptake system in P. tenuiflora. Compared with P. tenuiflora, the rice Oryza sativa was hypersensitive to saline-alkali stress. The results obtained using a noninvasive microtest techniques confirmed that the uptake of NO3- and NH4+ and the regulatory flux of Na+ and H+ were significantly higher in the roots of P. tenuiflora than in those of O. sativa. In the corresponding physiological experiments, the application of additional nutrition elements significantly eliminated the sensitive symptoms of rice to saline-alkali soil extracts.ConclusionsOur results imply that the survival of P. tenuiflora in saline-alkali soils is due to a combination of at least two regulatory mechanisms and the high nutrient uptake capacity of P. tenuiflora plays a pivotal role in its adaptation to those stress. Taken together, our results highlight the role of nutrition uptake in saline-alkali stress tolerance in plants.
Project description:This study reports a facile and eco-friendly method for the green synthesis of platinum and palladium nanoparticles (Pt NPs and Pd NPs) using Peganum harmala seed alkaloid fraction. The ζ-potential of the synthesized Pt NPs, Pd NPs and Pt-Pd NPs were -11.2 ± 0.5, -9.7 ±1.2, and -12.7 ± 2.1 mV; respectively. Transmission electron microscopy (TEM) revealed the formation of spherical-shaped nanoparticles with smooth margins. The mean diameters of the synthesized Pt NPs, Pd NPs, and Pt-Pd NPs were determined using TEM analysis and were found to be 20.3 ± 1.9, 22.5 ± 5.7, and 33.5 ± 5.4 nm, respectively. The nanoparticles' bioreduction was confirmed by ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, and their organic contents were determined by thermal gravimetric analysis (TGA). The Pt-Pd NPs mixture showed more pronounced antioxidant activity of 843.0 ± 60 μM Trolox equivalent (TE)/mg NPs compared to the individual Pt NPs (277.3 ± 13.5 μM TE/mg NPs) and Pd NPs (167.6 ± 4.8 μM TE/mg NPs). Furthermore, the Pt-Pd NPs exhibited significant cytotoxic activities against lung cancer (A549) and breast adenocarcinoma (MCF-7) cells, IC50 of 8.8 and 3.6 µg/mL, respectively; as compared to Pt NPs (IC50 of 10.9 and 6.7 µg/mL, respectively) and Pd NPs (IC50 of 31 and 10.8 µg/mL, respectively and compared to carboplatin (IC50 of 23 and 9.5 µg/mL, respectively). Moreover, molecular docking studies were conducted to explore the possible anticancer and antioxidant mechanisms of the biogenic nanoparticles. Pt NPs, Pd NPs, and their mixture showed inhibitory activity against cysteine proteinase, which supports their high antitumor activity, but moderate antioxidant activity. In conclusion, Pd-Pt NPs mixture prepared using harmala seed alkaloid fraction showed potential as effective antineoplastic agents.
Project description:The response and adaptation to drought remains poorly understood for Paulownia australis. To investigate this issue, transcriptome profiling of four P. australis accessions (two diploid and the other two autotetraploid) under water stress condition were studied using Illumina Genome Analyzer IIx analysis. The current study aimed to identify genes of P. australis metabolism pathways that might be involved in this plant's response to water deficit. Potted seedlings were subjected to well-watered conditions and drought stress, respectively. More than 290 million raw transcript reads were assembled into 111,660 unigenes, with a mean length of 1013 bp. Clusters of orthologous groups, gene ontology and the Kyoto Encyclopedia of Genes and Genomes annotations analyses were performed on the unigenes. Many differentially expressed genes and several metabolic pathways were identified. Quantitative real-time polymerase chain reaction was used to verify the expression patterns of 14 genes. Our study identified altered gene expression in P. australis induced by drought stress and provided a comprehensive map of drought-responsive genes and pathways in this species. To our knowledge, this is the first publicly available global transcriptome study of P. australis. This study provides a valuable genetic resource for this species.