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Glutathione plays a critical role in plant growth, development and response to stress. It is a major cellular antioxidant and is involved in the detoxification of xenobiotics in many organisms, including plants. However, the role of glutathione-dependent redox homeostasis and associated molecular mechanisms regulating the antioxidant system and pesticide metabolism remains unclear. In this study, endogenous glutathione levels were manipulated by pharmacological treatments with glutathione synthesis inhibitors and oxidized glutathione. The application of oxidized glutathione enriched the cellular oxidation state, reduced the activity and transcript levels of antioxidant enzymes, upregulated the expression level of nitric oxide and Ca2+ related genes and the content, and increased the residue of chlorothalonil in tomato leaves. Further experiments confirmed that glutathione-induced redox homeostasis is critical for the reduction of pesticide residues. RNA sequencing analysis revealed that miRNA156 and miRNA169 that target transcription factor SQUAMOSA-Promoter Binding Proteins (SBP) and NUCLEAR FACTOR Y (NFY) potentially participate in glutathione-mediated pesticide degradation in tomato plants. Our study provides important clues for further dissection of pesticide degradation mechanisms via miRNAs in plants.

Glutathione (GSH) biosynthesis and regeneration play a significant role in the metabolism of chlorothalonil (CHT) in tomatoes. However, the specific regulatory mechanism of GSH in the degradation of CHT remains uncertain. To address this, we investigate the critical regulatory pathways in the degradation of residual CHT in tomatoes. The results revealed that the detoxification of CHT residue in tomatoes was inhibited by buthionine sulfoximine and oxidized glutathione pretreatment, which increased by 26% and 46.12% compared with control, respectively. Gene silencing of γECS, GS, and GR also compromised the CHT detoxification potential of plants, which could be alleviated by GSH application and decreased the CHT accumulation by 33%, 25%, and 21%, respectively. Notably, it was found that the jasmonic acid (JA) pathway participated in the degradation of CHT regulated by GSH. CHT residues reduced by 28% after application of JA. JA played a role downstream of the glutathione pathway by promoting the degradation of CHT residue in tomatoes via nitric oxide signaling and improving the gene expression of antioxidant and detoxification-related enzymes. This study unveiled a crucial regulatory mechanism of GSH via the JA pathway in CHT degradation in tomatoes and offered new insights for understanding residual pesticide degradation.

Sugar metabolism is among the most important metabolic processes in soybean; it not only affects growth and development, but also plays a role in drought resistance. As a plant biological regulator, exogenous melatonin is assumed to regulate sugar metabolism. Here, physiological and transcriptomic approaches were used to determine the effects of melatonin on physiological indices and key genes and pathways associated with soybean sugar metabolism under drought stress. In plants subjected to drought stress, melatonin treatment increased dry matter accumulation, reduced malondialdehyde content, and increased the content of metabolized sugars in leaves, thereby enhancing soybean yield. Transcriptome analysis revealed that the genes differentially expressed in plants subjected to melatonin treatment and drought stress were enriched in the KEGG “sucrose and starch metabolism” pathway related to glucose metabolism. Among the differentially expressed genes, we identified 12 significantly altered genes associated with glucose metabolism that played roles in regulating the activities of glucose metabolism-related enzymes. Collectively, our results indicated that melatonin can enhance the output of glucose metabolites and tolerance of soybean subjected to drought stress by regulating the genes associated with glucose metabolism and activation of the related enzymes. Our findings provide a detailed theoretical basis for analyzing the regulatory effects of melatonin on soybean sugar metabolism under conditions of drought stress.

A high time resolution synchronous sampling method al ong with determination of stable carbon isotopes of gaseous water-soluble organic carbon (WSOCg) and particulate water-soluble organic carbon (WSOCp) was realized in this research through equipment modification and method improvement. It was found that WSOCg has significant higher concentration than WSOCp and a more depleted δ13C. Both concentrations of WSOCp and WSOCg have the seasonal variation characteristics of high in winter (WSOCp=15.7±3.9µg/m³; WSOCg=42.4±6.0µg/m³) and low in summer (WSOCp=5.9±1.8µg/m³; WSOCg=25.2±5.2µg/m³), with greater increase in WSOCp (167%) than that in WSOCg (68%). During wintertime, WSOCp and WSOCg had similar daily variation characteristics of concentration, and opposite daily variation characteristics of δ13C. WSOCp had a bimodal distribution with obvious low value at sunrise and sunset, while δ13C WSOCp had a unimodal distribution with low in daytime (-24.6±1.1‰) and high in nighttime (- 22.3±1.7‰). WSOCg and δ13C-WSOCg had same distribution with high in daytime and (49.3±8.8µg/m³; -27.9±1.1‰) low in nighttime (38.3±4.6µg/m³; -29.9±0.4‰). Combining the δ13C variation characteristics with the synchronous observation results of meteorological conditions, gaseous precursor pollutants, gaseous oxidants, gaseous acids and fine particle components, the restriction factors of WSOC gas-particle distribution mechanism were discussed. The presence of radiation rather than its intensity decided whether generations process of WSOCp and WSOCg are divided, for δ13C-WSOC of two phases showed significant correlation only during daytime. Meteorological conditions, gaseous precursor pollutants, gaseous oxidants and gaseous acids restrict the gas particle distribution of WSOC by affecting the aging process of WSOCp and WSOCg, gas particle conversion ratio of semi-volatile organic compounds (SVOC) and the gas phase and liquid phase generation ratio of WSOCp. At the same time, the gas-particle distribution process of WSOC is strongly related to the formation of secondary inorganic ions (nitrate, sulfate, ammonium), and the gas-particle distribution between gaseous nitrous acid and nitrite. [ABSTRACT FROM AUTHOR]

Synucleinopathies and abnormalities in the nerves of the enteric nervous system are hypothesized to be involved in age-associated motility disorders. The aim of the present study was to investigate the expression of various antigens, including a-synuclein (Syn) and its post-translational modified forms, in the human colon at various ages. In addition, the study aimed to correlate the expression of Syn with neurodegeneration. Immunohistochemistry was used to detect the expression of neurofilament (NF), Syn, as well as its nitrated (N) form in the healthy colonic tissue of 12 young (34.08±5.12 years), 10 middle-aged (51.80±3.52 years), and 11 elderly (75.82±7.70 years) individuals. To the best of our knowledge, the current study is the first to demonstrate the presence of N-Syn in the colonic tissue. N-Syn was identified in the upper layer of the mucosa and submucosa layer. Furthermore, Syn (wild-type) was present in the mucosa and submucosa. The number of NF-positive neurons in the submucosal layer declined significantly with age (P<0.01). In addition, Syn and N-Syn significantly increased during aging (P<0.01). Furthermore, a negative correlation was identified between neuron number and synucleinopathies, indicating the abnormal accumulation of both wild-type Syn and N-Syn in the mucosa, submucosa, muscle layer and myenteric plexus. The present study demonstrates that the Syn pathology may be linked to colic neuronal degeneration during normal aging, and this link may cause functional deficits. [ABSTRACT FROM AUTHOR]

Soda saline-alkali soil has double adverse effects on growth, morphogenesis and yield of the crops by creating a salinity stress and a high pH value in the rhizosphere surroundings of the plant. Seed priming can be an effective approach to enhance stress adaptation in seedlings growing in salinity stressed conditions. The present study examined the role of hydropriming and comprehensive seed priming with ZnSO4, CaCl2, betaine hydrochloride and GA3 to enhance the soda saline-alkali tolerance in soybeans (Glycine max [L.] Merr.) seedlings. An unprimed control treatment was also maintained for comparison. The results show that two seed priming treatments can effectively mitigate the negative effects of soda salinealkali stress. Nevertheless, compared with hydropriming, soybean seedlings from the comprehensive seed priming treatment had better growth performance through accumulation of soluble sugar and free proline contents, enhancing the activities of superoxide dismutase (SOD) and catalase (CAT), decreasing the malondialdehyde (MDA) content formed from lipid peroxidation, increasing the photosynthetic pigment contents, maintaining a better membrane integrity of the chloroplasts and mitochondria, and generating more starch grains in the chloroplasts of spongy mesophyll cells under soda saline-alkali stress. In conclusion, our results suggest that soybean seedlings from comprehensive seed priming exhibited a higher tolerance to soda saline-alkali stress than the unprimed control treatment. [ABSTRACT FROM AUTHOR]

High pressure water abrasive jet nozzle is key part of the particles acceleration. The diameter of nozzle has important effect for jet fluid. Through experiment and simulation explore the relationship between nozzle diameter and jet fluid cutting capacity. The result indicate: ①the cut depth and broad reduced in linearly relationship with the diameter of the jet nozzle. ②In same pressure, decrease the nozzle diameter will reduce the cutting ratio energy; ③The acceleration and attenuation of the nozzle axial flow in different diameters are basically consistent, The smaller nozzle diameter, The flow acceleration will slower, the attenuation will faster, the is velocity core segment will shorter and the cutting ability will lower;Consider from energy consumption, cutting efficiency and other factors, for common material cutting the nozzle preferred diameter is: 0.6~1.0mm, it’s unfavourable to select the 0.2mm diameter