Quinoa, a globally significant crop, is highly susceptible to low phosphorus stress, which can significantly impair its production and quality. Therefore, it is necessary to study the molecular mechanisms of quinoa's response to low phosphorus stress must be investigated. In this study, we identified a total of 14,824 genes and 1788 metabolites using transcriptomic and metabolomic techniques. Compared to the control group, 1378 and 8548 differentially expressed genes (DEGs), as well as 210 and 362 differentially accumulated metabolites (DAMs), were identified in the low phosphorus-treated groups, respectively. Bioinformatics analysis showed that these DEGs and DAMs are associated with various biological processes,for instance glycolysis, starch and sugar metabolism, pyruvate metabolism, glycerophospholipid metabolism, photosynthetic biosequestration, galactose metabolism, and citric acid cycle. Moreover, the results of the co-expression analysis highlighted interactions among DEGs and DAMs, particularly in the associated path to starch and sugar metabolism, glycerophospholipid metabolism, photosynthetic biosequestration, and glycolytic metabolic pathways. These results suggest that quinoa responds to low-phosphorus stress through these metabolic pathways. Overall, this study enhances our understanding of quinoa's mechanism in response to phosphorus deficiency and provides a reference for molecular design breeding of quinoa adapted to phosphorus deficiency.
The black spot disease caused by Alternaria alternata is one of the major diseases which seriously reduce the commercial value of muskmelon. This study was to investigate the possible effect against black spot disease in postharvest muskmelon (Cucumis melo L. cv. Xizhoumi 25) by fumigation with 60 μL/L nitric oxide (NO). Our results showed that NO decreased the lesion diameters and lesion depths of muskmelon inoculated with A.alternata, while NO maintained the structure and reduced the number of hyphae in tissues surrounding the netting sides. NO not only activated the activities of peroxidase (POD), phenylalanine aminolysis enzyme (PAL), cinnamic acid-4-hydroxylase (C4H) and 4-coumaric acid-CoA ligase (4CL), but also increased the content of total phenols, flavonoids and lignin. Moreover, β-1,3-glucanase (GLU) and chitinase (CHT) activities were promoted by NO. These results suggested that the regulation of phenylpropanoid pathway and pathogenesis-related proteins by NO were a possible mechanism for enhancing muskmelon resistance to black spot disease.
Nitrobenzene (NB) is recalcitrant to microbial biodegradation due to the electron-deficient character of the nitro group (NO2−). Prior work has found that the reductant could enhance NB biodegradation by providing excess electron donors. However, the existing theory couldn't explain the increase-and-decrease pattern of the NB biodegradation rate with an increase in a reductant concentration. Our results suggest that the reductant affects NB biodegradation by two mechanisms: the available electron donors and the stimulation or inhibition of biomass growth, which are linked by a pseudo-first-order reaction kinetics. In addition, the results showed that directly inoculating the plain soil into the aquatic system and then allowing the synergistic effect of the organic reductant (ascorbic acid) and the substrate (peptone) enhance NB biodegradation. Employing the new method, 200 mg L−1 NB was transformed in 72 h. GC–MS analysis detected two novel intermediate metabolites, indicating that NB was degraded into aniline and further transformed into acetanilide and 9-octadecenamide before its mineralization. This study sheds light on how to exploit the synergistic effects of the availability of excess electron donors and biomass growth by controlling the reductant and a substrate in the right concentration range (e.g., ascorbic acid < 0.8 mgL−1 + peptone).
The effects of blue light on photosynthetic organs have been studied. However, its effects on non-photosynthetic organs, in particular, on the early stages of rice caryopsis development, are unclear. Thus, we aimed to determine the metabolic characteristics of caryopsis development under blue light to improve the metabolic quality of crop kernels. We conducted a multi-omics analysis of each of the three periods from the beginning of cellular differentiation to the end of morphogenesis in post-pollination seeds of a japonica rice variety to explore the effect of blue light on metabolic levels during these metabolic changes and its genetic basis. It was found that blue light caused a gradual decrease in auxin content, a significant increase in the accumulation of JA and flavonoids, and a downregulation of the expression of many starch-related genes and proteins, leads to reduced starch synthesis and smaller starch granules. In addition, the gene co-expression network identified three transcription factors that may regulate starch and two that may regulate flavonoids. It was found through multi-omics testing that hormones such as jasmonic acid and auxins, and metabolites including alkaloids, flavonoids, lipids, organic acids, phenolic acids, and terpenoids altered significantly. Transcriptome and proteome analyses showed that blue light affected the seed nutrient repository activity. Specifically, starch- and gluten-related genes and proteins were significantly downregulated. Co- and WGCNA analyses identified several transcription factors that were regulated under blue light and identified key regulators of starch. Our study provides an understanding of the effects of blue light on post-flowering development in Gramineae and provides a framework for blue light-induced synthesis of secondary metabolites.
Reduced cortical gray matter integrity and cognitive abilities are among core deficits in schizophrenia. We hypothesized that higher allostatic load (AL) that accounts for exposure to chronic stress is a contributor to structural and cognitive deficits in schizophrenia. One hundred and sixty-seven schizophrenia patients who were on average with normal weight, normal systolic, and diastolic blood pressure and 72 healthy controls were enrolled in the study. Group differences in subclinical cardiovascular, metabolic, immune, and neuroendocrine biological markers as indexed by AL and contribution of AL components to the structural and cognitive deficits in schizophrenia were explored. Compared with controls, schizophrenia patients who were normotensive, normoweight, and had low total cholesterol levels still had significantly higher AL mainly due to lower high-density lipoprotein cholesterol and higher heart rate, waist-hip ratio, hemoglobinA1c, hypersensitive C-reactive protein, and overnight-urine cortisol levels. Patients also had decreased whole-brain mean cortical thickness, and lower cognition assessed by the MATRICS consensus cognitive battery. AL was inversely correlated with mean cortical thickness and cognition in schizophrenia, while none of these relationships existed in controls. Mediation analyses showed the effect of AL on cognitive deficits in schizophrenia was significantly mediated by cortical thinning, and the most significant mediating cortical area was the left superior frontal gyrus. Cortical thickness may act as a mediator between AL and cognitive deficits in schizophrenia. Early intervention strategies to reduce cortical thinning and cognitive dysfunction in schizophrenia should target specific aspects of their high AL in addition to weight gain, hypertension and high cholesterol levels.
An endophytic bacterium Bacillus velezensis BY6 was isolated from the wood stems of healthy Populus davidiana × P. alba var. pyramidalis (PdPap). The BY6 strain can inhibit pathogenic fungus Alternaria alternate in PdPap and promote growth of PdPap seedlings. In the present study, we used the Pacific Biosciences long-read sequencing platform, a single-molecule real-time (SMRT) technology for strain BY6, to perform complete genome sequencing. The genome size was 3,898,273 bp, the number of genes was 4,045, and the average GC content was 47.33%. A complete genome of strain BY6 contained 110 secondary metabolite gene clusters. Nine of the secondary metabolite gene clusters exhibited antifungal activity and promoted growth functions primarily involved in the synthesis of surfactin, bacteriocins, accumulated iron ions, and related antibiotics. Gene clusters provide genetic resources for biotechnology and genetic engineering, and enhance understanding of the relationship between microorganisms and plants.
