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Abstract Mitogen-activated protein kinase (MAPK) cascades are evolutionarily conserved in both plants and animals and play critical roles in activating innate immunity to defend against various pathogens. However, the role of MAPK cascades in positively regulating or enhancing viral infections in plants is unclear. In this study, we investigate the involvement of MAPK cascades in infection by the positive-strand RNA virus tomato chlorosis virus (ToCV). Our findings reveal that ToCV infection activates MAPK cascades, promoting virus spread within plants. Specifically, ToCV P7, a pathogenicity determinant protein, localizes to the plasma membrane and recruits NbMPK3/6 from the nucleus. Subsequently, P7 is directly phosphorylated on serine 59 by NbMPK3/6. Phosphorylated P7 interacts with NbREM1.1 and inhibits its ability to induce callose deposition at plasmodesmata. These results demonstrate that NbMPK3/6 directly phosphorylate ToCV P7, modulating antiviral defence mechanisms by downregulating callose deposition at plasmodesmata and thereby enhancing ToCV transmission in N. benthamiana. This study sheds light on the intricate arms race between host defence and viral counter-defence strategies.

Abstract Evidence for the treatment of patients with mild-to-moderate chronic obstructive pulmonary disease (COPD) is limited. The efficacy of N-acetylcysteine (an antioxidant and mucolytic agent) for patients with mild-to-moderate COPD is uncertain. In this multicentre, randomised, double-blind, placebo-controlled trial, we randomly assigned 968 patients with mild-to-moderate COPD to treatment with N-acetylcysteine (600 mg, twice daily) or matched placebo for two years. Eligible participants were 40-80 years of age and had mild-to-moderate COPD (forced expiratory volume in 1 second [FEV1] to forced vital capacity ratio

Abstract Background The clinical significance of the impulse oscillometry-defined small airway bronchodilator response (IOS-BDR) is not well-known. Accordingly, this study investigated the clinical characteristics of IOS-BDR and explored the association between lung function decline, acute respiratory exacerbations, and IOS-BDR. Methods Participants were recruited from an Early Chronic Obstructive Pulmonary Disease (ECOPD) cohort subset and were followed up for two years with visits at baseline, 12 months, and 24 months. Chronic obstructive pulmonary disease (COPD) was defined as a post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio

In this study, the fate, processing factors and relationship with physicochemical properties of thirteen pesticides in field-collected pepper samples during Chinese chopped pepper and chili powder production was systematically studied. The washing, air-drying, chopping and salting and fermentation processes reduced 24.8%–62.8%, 0.9%–26.4%, 25.1%–50.3% and 16.3%–90.0% of thirteen pesticide residues, respectively, while the sun-drying processing increased the residues of eleven pesticides by 1.27–5.19 fold. The PFs of thirteen pesticides were

IntroductionTomato chlorosis virus (ToCV) is a typical member of the genus Crinivirus, which severely threatens Solanaceae crops worldwide. The CPm protein encoded by ToCV has been reported to be associated with virus transmission by vectors and is involved in RNA silencing suppression, while the mechanisms remain ambiguous.MethodsHere, ToCV CPm was ectopically expressed by a Potato virus X (PVX) vector and infiltrated into Nicotiana benthamiana wild-type and GFP-transgenic16c plants.ResultsThe phylogenetic analysis showed that the CPm proteins encoded by criniviruses were distinctly divergent in amino acid sequences and predicted conserved domains, and the ToCV CPm protein possesses a conserved domain homologous to the TIGR02569 family protein, which does not occur in other criniviruses. Ectopic expression of ToCV CPm using a PVX vector resulted in severe mosaic symptoms followed by a hypersensitive-like response in N. benthamiana. Furthermore, agroinfiltration assays in N. benthamiana wilt type or GFP-transgenic 16c indicated that ToCV CPm protein effectively suppressed local RNA silencing induced by single-stranded but not double-stranded RNA, which probably resulted from the activity of binding double-stranded but not single-stranded RNA by ToCV CPm protein.ConclusionTaken together, the results of this study suggest that the ToCV CPm protein possesses the dual activities of pathogenicity and RNA silencing, which might inhibit host post-transcriptional gene silencing (PTGS)-mediated resistance and is pivotal in the primary process of ToCV infecting hosts.

The nuclear receptors HR3 and FTZ-F1 are highly conserved and function to regulate molting and reproduction in both hemimetabolous and holometabolous insects. However, their roles in Nilaparvata lugens are largely unknown. In the present study, we discover that NlHR3 and NlFTZ-F1 are activated in the nymph stages by ecdysone signaling. Transcription disruption of NlHR3 and NlFTZ-F1 expression prevents nymph ecdysis and metamorphosis, which leads to abnormal appearance, malformed ovaries, and lethal phenotypes. In addition, we demonstrate that NlHR3 and NlFTZ-F1 regulate molting and reproduction by interacting with the intrinsic 20E and JH signaling pathways. Our work offers a deep insight into the action mechanisms of HR3 and FTZ-F1 in insects. Moreover, NlHR3 and NlFTZ-F1 could properly be exploited as potential target genes for developing RNAi-based pesticides to control N. lugens.

Vacuolar ATPases (V-ATPases) are proton pumps for proton translocation across membranes that utilize energy derived from ATP hydrolysis; OsV-ATPase subunit d (OsV-ATPase d) is part of an integral, membrane-embedded V0 complex in the V-ATPase complex. Whether OsV-ATPase d is involved in phytohormone biosynthesis and resistance in rice remains unknown. The knockout mutants of OsV-ATPase d in rice were generated using the CRISPR/Cas9 system, and mutation of OsV-ATPase d did not show any detrimental effect on plant growth or yield productivity. Transcriptomic results showed that OsV-ATPase d is probably involved in mediating the biosynthesis of plant hormones and resistance in rice. Compared to wild type, mutation of OsV-ATPase d significantly increased JA and ABA biosynthesis and resistance against Southern rice black-streaked dwarf virus (SRBSDV), but it decreased resistance against Rice stripe virus (RSV) in rice. The data presented in this study reveal that OsV-ATPase d mediates phytohormone biosynthesis and virus resistance in rice and can be selected as a potential target for resistance breeding in rice.

BackgroundAttention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders in childhood and is caused by both genetic and environmental factors. As genetic factors are nonmodifiable, environmental factors have attracted increasing attention.ObjectiveTo investigate the relationships between urinary chlorpyrifos (CPF) levels, blood micronutrient levels, and ADHD prevalence in children living in rural areas of China.MethodsThis cross-sectional study collected data on CPF exposure (according to urinary levels), blood micronutrient levels, and ADHD prevalence in children aged 1–6 years in rural China. The CPF levels were determined by mass spectrometry. Blood levels of micronutrients, including zinc, iron, calcium, copper, magnesium, and vitamin D, were measured by professional detection kits. ADHD was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. Descriptive statistics and univariate analysis were conducted using SPSS 21.0, and path analysis was conducted using Mplus 8.0.ResultsOf the 738 children who met the eligibility criteria, 673 children (673/738, 91.2%) were included in the final analysis. Baseline questionnaires and urine samples were collected from all 673 subjects. A total of 672 children provided blood samples for micronutrient testing, and 651 completed the ADHD assessment. Approximately one-fifth of children (144/673, 21.4%) had detectable levels of CPF in their urine, and 6.9% (45/651) were diagnosed with ADHD. Path analysis showed that the total effect of CPF exposure on ADHD risk was 0.166 (P

Abstract Background Plant viruses move through plasmodesmata (PD) to infect new cells. To overcome the PD barrier, plant viruses have developed specific protein(s) to guide their genomic RNAs or DNAs to path through the PD. Results In the present study, we analyzed the function of Pepper vein yellows virus P4 protein. Our bioinformatic analysis using five commonly used algorithms showed that the P4 protein contains an transmembrane domain, encompassing the amino acid residue 117–138. The subcellular localization of P4 protein was found to target PD and form small punctates near walls. The P4 deletion mutant or the substitution mutant constructed by overlap PCR lost their function to produce punctates near the walls inside the fluorescent loci. The P4-YFP fusion was found to move from cell to cell in infiltrated leaves, and P4 could complement Cucumber mosaic virus movement protein deficiency mutant to move between cells. Conclusion Taking together, we consider that the P4 protein is a movement protein of Pepper vein yellows virus.

Abstract Full length open reading frame of pyrethroid detoxification gene, Est3385, contains 963 nucleotides. This gene was identified and cloned based on the genome sequence of Rhodopseudomonas palustris PSB-S available at the GneBank. The predicted amino acid sequence of Est3385 shared moderate identities (30–46%) with the known homologous esterases. Phylogenetic analysis revealed that Est3385 was a member in the esterase family I. Recombinant Est3385 was heterologous expressed in E. coli, purified and characterized for its substrate specificity, kinetics and stability under various conditions. The optimal temperature and pH for Est3385 were 35 °C and 6.0, respectively. This enzyme could detoxify various pyrethroid pesticides and degrade the optimal substrate fenpropathrin with a Km and Vmax value of 0.734 ± 0.013 mmol·l−1 and 0.918 ± 0.025 U·µg−1, respectively. No cofactor was found to affect Est3385 activity but substantial reduction of enzymatic activity was observed when metal ions were applied. Taken together, a new pyrethroid degradation esterase was identified and characterized. Modification of Est3385 with protein engineering toolsets should enhance its potential for field application to reduce the pesticide residue from agroecosystems.

GJ-22, a strain of the photosynthetic bacterium (PSB) capable of degrading cypermethrin (CPM), was isolated from the sludge from the wastewater treatment unit of an insecticide factory. The strain showed relatively high CPM degradation ability and was identified as Rhodopseudomonas palustris on the basis of its culture characteristics, co-lony and cell morphology, living cell absorption spectrum analysis, physiological and biochemical characteristics, type of internal photosynthetic membrane, and 16S rRNA sequence phylogenetic analysis. Single-factor tests showed that CPM degradation by GJ-22 was good from 25°C to 35°C, but that the optimal temperature was 30°C; a pH of 7.0 was optimal for both initial growth and CPM degradation. GJ-22 completely transformed CPM at a concentration of 50 mg/L at 30°C, pH 7.0, and 7,500 lux within 7 days. Under optimal conditions, within a week, GJ-22 degraded 83.5% of CPM, 77.1% of fenpropathrin, 71.2% of bifenthrin, and 31.1% of ethofenprox at concentrations of 100 mg/L. The metabolic products were detected by per-forming gas chromatography/mass spectrometry (GC/MS) analysis; the analysis showed that GJ-22 oxidation or/and hydrolysis degraded CPM, yielding 5 metabolites. [ABSTRACT FROM AUTHOR]

A novel bacterial strain capable of degrading the pyrethroid pesticide fenpropathrin was isolated from mixed wastewater and sludge samples. Phylogenetic analysis of the 16S rDNA sequence revealed that the organism belongs to the genus Clostridium. The organism can co-metabolically transform fenpropathrin at 100 mg l at 35°C and pH 7.5 in 12 days. Metabolic products of fenpropathrin from strain ZP3 were examined by gas chromatography/mass spectrometry, and the results showed that the organism degraded fenpropathrin with an oxidization process to yield benzyl alcohol, benzenemethanol, 3,5-dimethylamphetamine. Analyses of cell-free extracts from this strain showed that the optimal degrading conditions for degrading fenpropathrin were 35°C and pH 7.5, and degradation efficiency was 20.0 mg l day, and it might be potential using for rapid treating fenpropathrin, for example, on the surface of fruits and vegetables. [ABSTRACT FROM AUTHOR]

To isolate, select, identify and assess the potential for the biodegradation of fenpropathrin by photosynthetic bacterium, fenpropathrin-degrading photosynthetic bacteria were isolated by enrichment culture. Five isolates, which showed fenpropathrin biodegradation activity, were screened. Of these, strain PSB07-6 exhibited the highest fenpropathrin biodegradation potential, and was selected for further study. This strain was identified as Rhodopseudomonas sp. on the basis of morphology, physiological and biochemical characteristics, and 16S rRNA sequence analysis. The characteristics of this strain for degrading fenpropathrin were performed under different culture conditions. Optimum activity occurred at 35 °C and pH 7. Strain PSBO7-6 degraded 67.43% fenpropathrin (200 mg L-1) within 15 days. This strain could also degrade effectively cypermethrin, cyfluthrin, biphenthrin and esfenvalerate, except deltamethrin. Gas chromatography with mass selective detector (GC-MS) identified m-phenoxyphenyl-acetonitrile as the stable metabolic product, and from this a fenpropathrin biodegradation pathway is proposed. [ABSTRACT FROM AUTHOR]