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Singlet oxygen (1O2) has a very short half-life of 10-5 s; however, it is a strong oxidant that causes growth arrest and necrotic lesions on plants. Its signaling pathway remains largely unknown. The Arabidopsis flu (fluorescent) mutant accumulates a high level of 1O2 and shows drastic changes in nuclear gene expression. Only two plastid proteins, EX1 (executer 1) and EX2 (executer 2), have been identified in the singlet oxygen signaling. Here, we found that the transcription factor abscisic acid insensitive 4 (ABI4) binds the promoters of genes responsive to 1O2-signals. Inactivation of the ABI4 protein in the flu/abi4 double mutant was sufficient to compromise the changes of almost all 1O2-responsive-genes and rescued the lethal phenotype of flu grown under light/dark cycles, similar to the flu/ex1/ex2 triple mutant. In addition to cell death, we reported for the first time that 1O2 also induces cell wall thickening and stomatal development defect. Contrastingly, no apparent growth arrest was observed for the flu mutant under normal light/dim light cycles, but the cell wall thickening (doubled) and stomatal density reduction (by two-thirds) still occurred. These results offer a new idea for breeding stress tolerant plants.
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Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Luz , Oxigênio Singlete/metabolismo , Transcriptoma , Estômatos de Plantas/metabolismoRESUMO
Polycrystalline zinc selenide is widely used in advanced optical systems due to its superior optical properties. However, the soft and brittle properties bring a challenge for high-quality surface processing. In recent years, elliptical vibration cutting has been proven as a promising method for machining brittle materials. In the present research, a series of grooving and planning experiments were carried out to investigate the machinability of zinc selenide with elliptical vibration cutting. The removal mechanism was analyzed from fracture characteristics, chip morphology, and phase transformation. The results show that elliptical vibration cutting is effective in suppressing cleavage-induced craters. Reducing the nominal cutting speed is beneficial to inhibit the spring back-induced tearing of grains. A 94-time increase in the critical depth of cut was achieved by vibration trajectory optimization compared to ordinary cutting. Moreover, the influence mechanism of feed on the evolution of surface morphology was revealed. Finally, a zinc selenide microlens array was successfully fabricated. The performance was evaluated by geometric parameter measurements and a multiple imaging test. The findings provide a prospective method for ductile regime machining of zinc selenide.
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The detrimental impact of heavy metals on cardiovascular well-being is a global concern, and engaging in suitable physical activity has been shown to confer cardiovascular advantage. Nevertheless, the potential of exercise to mitigate the deleterious effects of heavy metals on stroke remains uncertain. We conducted a cross-sectional survey to assess the influence of blood cadmium and blood lead on stroke occurrence, while also examining the role of physical activity. Weighted multivariate regression analysis was employed to examine the potential correlation, while subgroup and interaction analyses were used to investigate the sensitivity and robustness of the results. After controlling risk factors, it revealed a positive correlation between blood cadmium and lead levels and the occurrence of stroke. Specifically, a 50% increase in blood cadmium was associated with a 28% increase in stroke incidence, while a 50% increase in blood lead was associated with a 47% increase in stroke incidence. To estimate the non-linear relationship, we employed restricted cubic models. The results demonstrate a gradual decrease in the slope of the model curve as the intensity of physical activity increases, implying that engaging in physical activity may contribute to a reduction in the occurrence of stroke caused by blood cadmium and lead. Our findings suggest that blood cadmium and lead could be considered an autonomous risk factor for stroke within the general population of the United States. Moreover, engaging in physical activity has the potential to mitigate the potential detrimental consequences associated with exposure to heavy metals.
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Metais Pesados , Acidente Vascular Cerebral , Humanos , Estados Unidos/epidemiologia , Cádmio/toxicidade , Chumbo/toxicidade , Inquéritos Nutricionais , Estudos Transversais , Metais Pesados/toxicidade , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controleRESUMO
OBJECTIVES: Studies have shown that depression increases the risk of stroke, and that this relationship can be modified by sex. However, few studies have explored this relationship in a hypertensive population, and an examination of sociodemographic factors may be useful in determining whether depression and stroke are related. MATERIALS AND METHODS: We used data from the National Health and Nutrition Examination Survey conducted between 2005-2018. The relationship between depression and stroke was investigated using a multivariate logistic regression. Effect modification by sex was examined using an interaction analysis model. RESULTS: Participants with mild or moderate depression had a 53 % (odds ratio, [OR] 1.53; 95 % confidence interval [CI], 1.15-2.04) higher risk of stroke than those without depression, with 1.76 times (95 % CI, 1.14-2.72) greater risk for major depression. Interaction analysis indicated that sex had no effect on this relationship (OR, 1.30; 95 % CI, 0.85-1.47, P=0.430). In comparison with Hispanics, non-Hispanic blacks and others/mixed-race individuals with depression had a greater risk of stroke (OR, 2.26; 95 % CI, 1.5-3.14; OR, 2.67, 95 % CI, 1.29-5.55). CONCLUSIONS: Our study found that the degree of depression was positively correlated with stroke in a hypertensive population, and that this relationship was not affected by sex.
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Hipertensão , Acidente Vascular Cerebral , Humanos , Depressão/diagnóstico , Depressão/epidemiologia , Inquéritos Nutricionais , Fatores Sociodemográficos , Fatores de Risco , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologiaRESUMO
Sweetpotato (Ipomoea batatas (L.) Lam.) is a globally significant storage root crop, but it is highly susceptible to yield reduction under severe drought conditions. Therefore, understanding the mechanism of sweetpotato resistance to drought stress is helpful for the creation of outstanding germplasm and the selection of varieties with strong drought resistance. In this study, we conducted a comprehensive analysis of the phenotypic and physiological traits of 17 sweetpotato breeding lines and 10 varieties under drought stress through a 48 h treatment in a Hoagland culture medium containing 20% PEG6000. The results showed that the relative water content (RWC) and vine-tip fresh-weight reduction (VTFWR) in XS161819 were 1.17 and 1.14 times higher than those for the recognized drought-resistant variety Chaoshu 1. We conducted RNA-seq analysis and weighted gene co-expression network analysis (WGCNA) on two genotypes, XS161819 and 18-12-3, which exhibited significant differences in drought resistance. The transcriptome analysis revealed that the hormone signaling pathway may play a crucial role in determining the drought resistance in sweetpotato. By applying WGCNA, we identified twenty-two differential expression modules, and the midnight blue module showed a strong positive correlation with drought resistance characteristics. Moreover, twenty candidate Hub genes were identified, including g47370 (AFP2), g14296 (CDKF), and g60091 (SPBC2A9), which are potentially involved in the regulation of drought resistance in sweetpotato. These findings provide important insights into the molecular mechanisms underlying drought resistance in sweetpotato and offer valuable genetic resources for the development of drought-resistant sweetpotato varieties in the future.
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Ipomoea batatas , Transcriptoma , Resistência à Seca , Ipomoea batatas/genética , Melhoramento Vegetal , Perfilação da Expressão GênicaRESUMO
Galectin-10 (Gal-10) forms Charcot-Leyden crystals (CLCs), which play a key role in the symptoms of asthma and allergies and some other diseases. Gal-10 has a carbohydrate-binding site; however, neither the Gal-10 dimer nor the CLCs can bind sugars. To investigate the monomer-dimer equilibrium of Gal-10, high-performance size-exclusion chromatography (SEC) was employed to separate serial dilutions of Gal-10 with and without carbohydrates. We found that both the dimerization and crystallization of Gal-10 were promoted by lactose/galactose binding. A peak position shift for the monomer was observed after treatment with either lactose or galactose, implying that the polarity of the monomer was reduced by lactose/galactose binding. Further experiments indicated that alkaline conditions of pH 8.8 mimicked the lactose/galactose-binding environment, and the time interval between monomers and dimers in the chromatogram decreased from 0.8 min to 0.4 min. Subsequently, the electrostatic potential of the Gal-10 monomers was computed. After lactose/galactose binding, the top side of the monomer shifted from negatively charged to electrically neutral, allowing it to interact with the carbohydrate-binding site of the opposing subunit during dimerization. Since lactose/galactose promotes the crystallization of Gal-10, our findings implied that dairy-free diets (free of lactose/galactose) might be beneficial to patients with CLC-related diseases.
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Galactose , Lactose , Humanos , Lactose/química , Galactose/metabolismo , Cristalização , Galectinas/química , Sítios de LigaçãoRESUMO
Amantadine, an antiviral drug, has been widely used in human anti-influenza treatments. However, several highly pathogenic avian influenza viruses show amantadine-resistance mutations in the viral matrix 2 (M2) protein. Here we analyzed global H5N1 sequencing data and calculate possible correlations between frequencies of key mutations in M2 and the mortality rates. We found that the frequency of L26I/V27A mutation in M2 (isolated from both human and avian hosts) is linearly correlated with the mortality rates of human H5N1 infections. The significant correlation between M2 mutations in avians and the mortality rates in humans suggests that the pre-existence of L26I/V27A in birds may determine patient fatalities after transinfections from avian to human hosts. 100% prevalence of L26I/V27A mutation increased the mortality rates from 51% (95% confidence interval [CI] 37%-65%) to 89% (95% CI 88%-90%). Mutations involving Leu26 or Val27 were identified to be the major mutations emerging from drug selection pressure. Thus the emergence of the super H5N1 virus with a fatality of over 90% may be attributed to the abuse of amantadine in poultry, especially in some southeast Asian countries. A more stringent control to antiviral veterinary drugs is imperative.
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Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Influenza Humana , Amantadina/farmacologia , Amantadina/uso terapêutico , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Aves , Farmacorresistência Viral/genética , Humanos , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/epidemiologia , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Filogenia , Aves Domésticas , Proteínas da Matriz Viral/genéticaRESUMO
Nitrate reductase (NR) is one of the key enzymes for plant nitrogen assimilation and root architecture remodeling. However, crosstalk between NR-mediated signaling and auxin-mediated root development in nitrogen-status responses has not been investigated in details before. In this study, root phenotype and auxin distribution in nia1/nia2 (nitrate reductase) double mutant and chl1-5 (nitrate transporter NRT1.1) mutant under different nitrogen availabilities were compared. The nia1/nia2 mutant showed very low expression levels of auxin biosynthetic/signaling genes and was insensitive to nitrogen changes. While the chl1-5 mutant showed a high NR activity with a high level of auxin in the meristematic zone and a weaker response to nitrogen changes, when compared with the wild-type plants. We firstly found that NR activity was roughly positive-correlated with the root auxin level, and there is a crosstalk between nitrate signaling and auxin signaling. The putative signaling pathways downstream of NR have been discussed.
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Arabidopsis/enzimologia , Ácidos Indolacéticos/metabolismo , Nitrato Redutase/metabolismo , Nitrogênio/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação , Nitrato Redutase/genética , Nitrato Redutase/fisiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismoRESUMO
Nitrogen (N), phosphorus (P), and potassium (K) are three essential macro-elements for plant growth and development. Used to improve yield in agricultural production, the excessive use of chemical fertilizers often leads to increased production costs and ecological environmental pollution. Vitamins C and E are antioxidants that play an important role in alleviating abiotic stress. However, there are few studies on alleviating oxidative stress caused by macro-element deficiency. Here, we used Arabidopsis vitamin E synthesis-deficient mutant vte4 and vitamin C synthesis-deficient mutant vtc1 on which exogenous vitamin E and vitamin C, respectively, were applied at the bolting stage. In the deficiency of macro-elements, the Arabidopsis chlorophyll content decreased, malondialdehyde (MDA) content and relative electric conductivity increased, and reactive oxygen species (ROS) accumulated. The mutants vtc1 and vte4 are more severely stressed than the wild-type plants. Adding exogenous vitamin E was found to better alleviate stress than adding vitamin C. Vitamin C barely affected and vitamin E significantly inhibited the synthesis of ethylene (ETH) and jasmonic acid (JA) genes, thereby reducing the accumulation of ETH and JA that alleviated the senescence caused by macro-element deficiency at the later stage of bolting in Arabidopsis. A deficiency of macro-elements also reduced the yield and germination rate of the seeds, which were more apparent in vtc1 and vte4, and adding exogenous vitamin C and vitamin E, respectively, could restore them. This study reported, for the first time, that vitamin E is better than vitamin C in delaying seedling senescence caused by macro-element deficiency in Arabidopsis.
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Antioxidantes/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Ácido Ascórbico/farmacologia , Resistência à Doença/efeitos dos fármacos , Plântula/efeitos dos fármacos , Vitamina E/farmacologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Clorofila/metabolismo , Ciclopentanos/antagonistas & inibidores , Ciclopentanos/metabolismo , Etilenos/antagonistas & inibidores , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxilipinas/antagonistas & inibidores , Oxilipinas/metabolismo , Doenças das Plantas/prevenção & controle , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/genética , Plântula/metabolismo , Sementes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
MAIN CONCLUSION: The 5-leaf-stage rape seedlings were more insensitive to Pi starvation than that of the 3-leaf-stage plants, which may be attributed to the higher expression levels of ethylene signaling and sugar-metabolism genes in more mature seedlings. Traditional suppression subtractive hybridization (SSH) and RNA-Seq usually screen out thousands of differentially expressed genes. However, identification of the most important regulators has not been performed to date. Here, we employed two methods, namely, a two-round SSH and two-factor transcriptome analysis derived from the two-factor ANOVA that is commonly used in the statistics, to identify development-associated inorganic phosphate (Pi) starvation-induced genes in Brassica napus. Several of these genes are related to ethylene signaling (such as EIN3, ACO3, ACS8, ERF1A, and ERF2) or sugar metabolism (such as ACC2, GH3, LHCB1.4, XTH4, and SUS2). Although sucrose and ethylene may counteract each other at the biosynthetic level, they may also work synergistically on Pi-starvation-induced gene expression (such as PT1, PT2, RNS1, ACP5, AT4, and IPS1) and root acid phosphatase activation. Furthermore, three new transcription factors that are responsive to Pi starvation were identified: the zinc-finger MYND domain-containing protein 15 (MYND), a Magonashi family protein (MAGO), and a B-box zinc-finger family salt-tolerance protein. This study indicates that the two methods are highly efficient for functional gene screening in non-model organisms.
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Brassica napus/genética , Regulação da Expressão Gênica de Plantas , Fosfatos/deficiência , Transdução de Sinais , Fatores de Transcrição/genética , Transcriptoma , Análise de Variância , Brassica napus/crescimento & desenvolvimento , Brassica napus/fisiologia , Etilenos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fosfatos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análise de Sequência de RNA , Técnicas de Hibridização Subtrativa , Fatores de Transcrição/metabolismoRESUMO
Nitric oxide (NO) has a general inhibitory effects on chlorophyll biosynthesis, especially to the step of 5-aminolevulinic acid (ALA) biosynthesis and protochlorophyllide (Pchlide) to chlorophyllide (Chlide) conversion (responsible by the NADPH:Pchlide oxidoreductase POR). Previous study suggested that barley large POR aggregates may be generated by dithiol oxidation of cysteines of two POR monomers, which can be disconnected by some reducing agents. POR aggregate assembly may be correlated with seedling greening in barley, but not in Arabidopsis. Thus, NO may affect POR activity and seedling greening differently between Arabidopsis and barley. We proved this assumption by non-denaturing gel-analysis and reactive oxygen species (ROS) monitoring during the greening. NO treatments cause S-nitrosylation to POR cysteine residues and disassembly of POR aggregates. This modification reduces POR activity and induces Pchlide accumulation and singlet oxygen generation upon dark-to-high-light shift (and therefore inducing photobleaching lesions) in barley leaf apex, but not in Arabidopsis seedlings. ROS staining and ROS-related-gene expression detection confirmed that superoxide anion and singlet oxygen accumulated in barley etiolated seedlings after the NO treatments, when exposed to a fluctuating light. The data suggest that POR aggregate assembly may be correlated with barley chlorophyll biosynthesis and redox homeostasis during greening. Cysteine S-nitrosylation may be one of the key reasons for the NO-induced inhibition to chlorophyll biosynthetic enzymes.
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Arabidopsis/metabolismo , Clorofilídeos/biossíntese , Hordeum/metabolismo , Óxido Nítrico/metabolismo , Oxigênio Singlete/metabolismoRESUMO
The role of inflammation in disease promotion is significant, yet the precise association between a newly identified inflammatory biomarker and insulin resistance (IR) and mortality remains uncertain. We aim to explore the potential correlation between systemic immune-inflammation index (SII) and these factors. We used data from 2011 to 2016 of National Health and Nutrition Examination Survey, and multivariate logistic regression and restricted cubic spline were employed. Subgroup and interaction analysis were conducted to recognize the consistency of the results. The association between SII and mortality was described by survival analysis. 6734 participants were enrolled, of whom 49.3% (3318) exhibited IR and 7.02% experienced mortality. Multivariate logistic regression revealed that individuals in the highest quartile (Q4) of SII had a significantly increased risk of IR compared to those in the lowest quartile (Q1). We then identified a linear association between SII and IR with an inflection point of 407, but may be influenced by gender. Similarly, compared to Q1, people whose SII at Q4 showed a higher all-cause and cardiovascular mortality. It showed a significant association between SII and both all-cause and cardiovascular mortality, but the results need to be interpreted with caution.
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Doenças Cardiovasculares , Resistência à Insulina , Mortalidade , Humanos , Doenças Cardiovasculares/mortalidade , Interpretação Estatística de Dados , Inflamação , Inquéritos NutricionaisRESUMO
Sweetpotato blades are rich in the functional secondary metabolite chlorogenic acid (CGA), which deepen potential for effective utilization of the blade in industry. In this study, we evaluated the type and content of CGA in the blades of 16 sweetpotato genotypes and analyzed the correlation between CGA content and antioxidant capacity. Then we isolated and characterized IbGLK1, a GARP-type transcription factor, by comparative transcriptome analysis. A subcellular localization assay indicated that IbGLK1 is located in the nucleus. Overexpression and silencing of IbGLK1 in sweetpotato blade resulted in a 0.90-fold increase and 1.84-fold decrease, respectively, in CGA content compared to the control. Yeast one-hybrid and dual-luciferase assays showed that IbGLK1 binds and activates the promoters of IbHCT, IbHQT, IbC4H, and IbUGCT, resulting in the promotion of CGA biosynthesis. In conclusion, our study provides insights into a high-quality gene for the regulation of CGA metabolism and germplasm resources for breeding sweetpotato.
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Ácido Clorogênico , Regulação da Expressão Gênica de Plantas , Ipomoea batatas , Proteínas de Plantas , Fatores de Transcrição , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Ácido Clorogênico/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma , Perfilação da Expressão Gênica , Regiões Promotoras GenéticasRESUMO
BACKGROUND: The study of changes in the microbiome in chronic pancreatitis (CP) and pancreatic ductal adenocarcinoma (PDAC) holds significant potential for developing noninvasive diagnostic tools as well as innovative interventions to alter the progression of diseases. This systematic review and meta-analysis aimed to analyze in detail the taxonomic and functional characteristics of the gut microbiome in patients with CP and PDAC. METHODS: Two researchers conducted a systematic search across public databases to gather all published research up to June 2023. Diversity and gut microbiota composition are the main outcomes we focus on. RESULTS: This meta-analysis included 14 studies, involving a total of 1511 individuals in the PDAC (n=285), CP (n=342), and control (n=649) groups. Our results show a significant difference in the composition of gut microbiota between PDAC/CP patients compared to healthy controls (HC), as evidenced by a slight decrease in α-diversity, including Shannon (SMD=-0.33; P=0.002 and SMD=-0.59; P<0.001, respectively) and a statistically significant ß-diversity (P<0.05). The pooled results showed that at the phylum level, the proportion of Firmicutes was lower in PDAC and CP patients than in HC patients. At the genus level, more than two studies demonstrated that 4 genera were significantly increased in PDAC patients compared to HC (e.g., Escherichia-Shigella and Veillonella). CP patients had an increase in 4 genera (e.g., Escherichia-Shigella and Klebsiella) and a decrease in 8 genera (e.g., Coprococcus and Bifidobacterium) compared to HC. Functional/metabolomics results from various studies also showed differences between PDAC/CP patients and HC. In addition, this study found no significant differences in gut microbiota between PDAC and CP patients. CONCLUSIONS: Current evidence suggests changes in gut microbiota is associated with PDAC/CP, commonly reflected by a reduction in beneficial species and an increase in the pathogenic species. Further studies are needed to confirm these findings and explore therapeutic possibilities.
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Coronavirus Disease 2019 (COVID-19) vaccines protect the public and limit viral spread. However, inactivated viral vaccines use the whole virus particle, which contains many non-capsid proteins that may cause adverse immune responses. A report has found that the ADP-ribose-binding domains of SARS-CoV-2 non-structural protein 3 (NSP3) and human poly(ADP-ribose) polymerase family member 14 (PARP14) share a significant degree of homology. Here, we further show that antibodies against 2019 novel SARS-like coronavirus (SARS-CoV-2) NSP3 can bind human PARP14 protein. However, when G159R + G162R mutations were introduced into NSP3, the antibody titer against human PARP14 decreased 14-fold. Antibodies against SARS-CoV-2 NSP3 can cross-react with human skeletal muscle cells and astrocytes, but not human embryonic kidney 293T cells. However, when G159R + G162R mutations were introduced into NSP3, the cross-reaction was largely inhibited. The results imply that COVID-19 patients with high antibody titers against NSP3 may have high risks of muscular and/or neurological complications. And the possible strategies to improve the safety of inactivated viral vaccines are also discussed.
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COVID-19 , Vacinas Virais , Humanos , SARS-CoV-2/genética , Proteínas não Estruturais Virais/química , Vacinas contra COVID-19 , Anticorpos , Células Musculares/metabolismo , Neuroglia/metabolismoRESUMO
Fusarium wilt is a severe fungal disease caused by Fusarium oxysporum in sweet potato. We conducted transcriptome analysis to explore the resistance mechanism of sweet potato against F. oxysporum. Our findings highlighted the role of scopoletin, a hydroxycoumarin, in enhancing resistance. In vitro experiments confirmed that scopoletin and umbelliferone had inhibitory effects on the F. oxysporum growth. We identified hydroxycoumarin synthase genes IbF6'H2 and IbCOSY that are responsible for scopoletin production in sweet potatoes. The co-overexpression of IbF6'H2 and IbCOSY in tobacco plants produced the highest scopoletin levels and disease resistance. This study provides insights into the molecular basis of sweet potato defense against Fusarium wilt and identifies valuable genes for breeding wilt-resistant cultivars.
Assuntos
Fusarium , Ipomoea batatas , Ipomoea batatas/genética , Escopoletina/farmacologia , Fusarium/genética , Melhoramento Vegetal , Doenças das Plantas/microbiologiaRESUMO
To increase the imaging resolution and detection capability, the field strength of static magnetic fields (SMFs) in magnetic resonance imaging (MRI) has significantly increased in the past few decades. However, research on the side effects of high magnetic field is still very inadequate and the effects of SMF above 1 T (Tesla) on B cells have never been reported. Here, we show that 33.0 T ultra-high SMF exposure causes immunosuppression and disrupts B cell differentiation and signaling. 33.0 T SMF treatment resulted in disturbance of B cell peripheral differentiation and antibody secretion and reduced the expression of IgM on B cell membrane, and these might be intensity dependent. In addition, mice exposed to 33.0 T SMF showed inhibition on early activation of B cells, including B cell spreading, B cell receptor clustering and signalosome recruitment, and depression of both positive and negative molecules in the proximal BCR signaling, as well as impaired actin reorganization. Sequencing and gene enrichment analysis showed that SMF stimulation also affects splenic B cells' transcriptome and metabolic pathways. Therefore, in the clinical application of MRI, we should consider the influence of SMF on the immune system and choose the optimal intensity for treatment.
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Nitrogen is one of the important nutrients required for plant growth and development. There is increasing evidences that almost all types of nitrogen metabolites affect, at least to some extent, auxin content and/or signaling in plants, which in turn affects seed germination, plant root elongation, gravitropism, leaf expansion and floral transition. This opinion focuses on the roles of nitrogen metabolites, NO 3 - , NH 4 + , tryptophan and NO and their synergistic effects with auxin on plant growth and development. Nitrate reductase (NR) converts nitrate into nitrite, and was roughly positive-correlated with the root auxin level, suggesting a crosstalk between nitrate signaling and auxin signaling. Abscisic Acid Responsive Element Binding Factor 3 (AFB3) and Tryptophan Aminotransferase of Arabidopsis 1 (TAA1) are also the key enzymes involved in nitrogen metabolite-regulated auxin biosynthesis. Recent advances in the crosstalk among NO 3 - , NH 4 + , tryptophan and NO in regulation to NR, AFB3 and TAA1 are also summarized.
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Sweetpotato (Ipomoea batatas (L.) Lam.), which has a complex genome, is one of the most important storage root crops in the world. Sweetpotato blades are considered as a potential source of natural antioxidants owing to their high phenolic content with powerful free radical scavenging ability. The molecular mechanism of phenolic metabolism in sweetpotato blades has been seldom reported thus far. In this work, 23 sweetpotato genotypes were used for the analysis of their antioxidant activity, total polyphenol content (TPC) and total flavonoid content (TFC). 'Shangshu19' and 'Wan1314-6' were used for RNA-seq. The results showed that antioxidant activity, TPC and TFC of 23 genotypes had significant difference. There was a significant positive correlation between TPC, TFC and antioxidant activity. The RNA-seq analysis results of two genotypes, 'Shangshu19' and 'Wan1314-6', which had significant differences in antioxidant activity, TPC and TFC, showed that there were 7810 differentially expressed genes (DEGs) between the two genotypes. Phenylpropanoid biosynthesis was the main differential pathway, and upregulated genes were mainly annotated to chlorogenic acid, flavonoid and lignin biosynthesis pathways. Our results establish a theoretical and practical basis for sweetpotato breeding with antioxidant activity and phenolics in the blades and provide a theoretical basis for the study of phenolic metabolism engineering in sweetpotato blade.