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1.
Sports Med Open ; 10(1): 33, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589676

RESUMO

BACKGROUND: Chronic ankle instability (CAI) is manifested by sensorimotor impairments in the sprained ankle, including deficits in sensation, motor function, and central integration or processing. These impairments have a significant impact on physical activities and daily life. Recently, some studies have suggested that bilateral deficits were observed in unilateral CAI, but contradictory evidence disputes this finding. Therefore, the objective of this study was to investigate whether bilateral sensorimotor deficits presented in individuals with unilateral CAI. METHODS: Without language restriction, the following databases were retrieved from database inception up until 3 November 2023, including PubMed, WOS, EMBASE, Cochrane, SPORTDiscus and CINAHL. Case-control and cross-sectional studies that investigated bilateral sensorimotor functions in individuals with unilateral CAI were included. Sensorimotor functions contained static and dynamic balance, functional performance, muscle strength and activation, as well as sensation. Outcome measures contained centre-of-pressure parameters, normalised reach distance, activation time and magnitude of muscle, sensory errors and threshold. The risk of bias and quality assessment of included studies were evaluated using a standardised tool recommended by the Cochrane Collaboration and the Epidemiological Appraisal Instrument, respectively. To explore the potential bilateral deficits associated with unilateral CAI, a comprehensive meta-analysis was conducted using Review Manager version 5.4. The analysis compared the injured limb of unilateral CAI with healthy controls and the uninjured limb with healthy controls. The main focus of this study was to investigate the differences between the uninjured limb and healthy controls. A random-effects model was employed and effect sizes were estimated using the standardised mean difference (SMD) with 95% confidence intervals (CIs). Effect sizes were deemed as weak (0.2-0.5), moderate (0.5-0.8), or large (> 0.8). RESULTS: A total of 11,442 studies were found; 30 studies were contained in the systematic review and 20 studies were included in the meta-analysis. Compared with healthy controls, those with unilateral CAI presented weak to moderate impairments in their uninjured limbs in static balance with eyes open (SMD = 0.32, 95% CI: 0.08 to 0.56), functional performance (SMD = 0.37; 95% CI: 0.08 to 0.67), kinesthesia (SMD = 0.52; 95% CI: 0.09 to 0.95) and tibialis anterior activation (SMD = 0.60, 95% CI: 0.19 to 1.01). There were no significant differences in other comparisons between the uninjured limb and healthy controls. CONCLUSIONS: Patients with unilateral CAI may present bilateral deficits in static balance with eyes open, functional performance and kinaesthesia. However, further evidence is required to confirm this point due to limited studies included in some analyses and small effect size. REGISTRATION: The protocol was registered in the International Prospective Register of Systematic Reviews platform (CRD: 42,022,375,855).

2.
Front Microbiol ; 15: 1370427, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572228

RESUMO

Clubroot, caused by Plasmodiophora brassicae, is a major disease that significantly impairs the yield of cruciferous crops and causes significant economic losses across the globe. The prevention of clubroot, especially in tumorous stem mustard (without resistant varieties), are is limited and primarily relies on fungicides. Engineered nanoparticles have opened up new avenues for the management of plant diseases, but there is no report on their application in the prevention of clubroot. The results showed that the control efficacy of 500 mg/L MgO NPs against clubroot was 54.92%. However, when the concentration was increased to 1,500 and 2,500 mg/L, there was no significant change in the control effect. Compared with CK, the average fresh and dry weight of the aerial part of plants treated with MgO NPs increased by 392.83 and 240.81%, respectively. Compared with the F1000 treatment, increases were observed in the content of soil available phosphorus (+16.72%), potassium (+9.82%), exchangeable magnesium (+24.20%), and water-soluble magnesium (+20.64%) in the 1,500 mg/L MgO NPs treatment. The enzyme-linked immune sorbent assay (ELISA) results showed that the application of MgO NPs significantly increased soil peroxidase (POD, +52.69%), alkaline protease (AP, +41.21%), alkaline phosphatase (ALP, +79.26%), urease (+52.69%), and sucrase (+56.88%) activities; And also increased plant L-phenylalanine ammonla-lyase (PAL, +70.49%), polyphenol oxidase (PPO, +36.77%), POD (+38.30%), guaiacol peroxidase (POX, +55.46%) activities and salicylic acid (SA, +59.86%) content. However, soil and plant catalase (CAT, -27.22 and - 19.89%, respectively), and plant super oxidase dismutase (SOD, -36.33%) activities were significantly decreased after the application of MgO NPs. The metagenomic sequencing analysis showed that the MgO NPs treatments significantly improved the α-diversity of the rhizosphere soil microbial community. The relative abundance of beneficial bacteria genera in the rhizosphere soil, including Pseudomonas, Sphingopyxis, Acidovorax, Variovorax, and Bosea, was significantly increased. Soil metabolic functions, such as oxidative phosphorylation (ko00190), carbon fixation pathways in prokaryotes (ko00720), indole alkaloid biosynthesis (ko00901), and biosynthesis of various antibiotics (ko00998) were significantly enriched. These results suggested that MgO NPs might control clubroot by promoting the transformation and utilization of soil nutrients, stimulating plant defense responses, and enriching soil beneficial bacteria.

3.
Chem Commun (Camb) ; 60(21): 2906-2909, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38363097

RESUMO

A phosphoric acid additive with an optimal concentration of 0.1 M can vastly promote the diffusion kinetics of the redox reaction between V(IV) and V(V) without a significant decline in energy efficiency for 300 cycles, and maintain the high-temperature stability (55 °C) of an electrolyte at a high state of charge (SOC) of 70% over the course of 30 days.

4.
Front Artif Intell ; 6: 1323924, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38145231

RESUMO

Introduction: Artificial intelligence (AI) technology has made rapid progress for disease diagnosis and triage. In the field of ophthalmic diseases, image-based diagnosis has achieved high accuracy but still encounters limitations due to the lack of medical history. The emergence of ChatGPT enables human-computer interaction, allowing for the development of a multimodal AI system that integrates interactive text and image information. Objective: To develop a multimodal AI system using ChatGPT and anterior segment images for diagnosing and triaging ophthalmic diseases. To assess the AI system's performance through a two-stage cross-sectional study, starting with silent evaluation and followed by early clinical evaluation in outpatient clinics. Methods and analysis: Our study will be conducted across three distinct centers in Shanghai, Nanjing, and Suqian. The development of the smartphone-based multimodal AI system will take place in Shanghai with the goal of achieving ≥90% sensitivity and ≥95% specificity for diagnosing and triaging ophthalmic diseases. The first stage of the cross-sectional study will explore the system's performance in Shanghai's outpatient clinics. Medical histories will be collected without patient interaction, and anterior segment images will be captured using slit lamp equipment. This stage aims for ≥85% sensitivity and ≥95% specificity with a sample size of 100 patients. The second stage will take place at three locations, with Shanghai serving as the internal validation dataset, and Nanjing and Suqian as the external validation dataset. Medical history will be collected through patient interviews, and anterior segment images will be captured via smartphone devices. An expert panel will establish reference standards and assess AI accuracy for diagnosis and triage throughout all stages. A one-vs.-rest strategy will be used for data analysis, and a post-hoc power calculation will be performed to evaluate the impact of disease types on AI performance. Discussion: Our study may provide a user-friendly smartphone-based multimodal AI system for diagnosis and triage of ophthalmic diseases. This innovative system may support early detection of ocular abnormalities, facilitate establishment of a tiered healthcare system, and reduce the burdens on tertiary facilities. Trial registration: The study was registered in ClinicalTrials.gov on June 25th, 2023 (NCT05930444).

5.
Int J Mol Sci ; 24(18)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37762441

RESUMO

Crocins are a group of highly valuable water-soluble carotenoids that are reported to have many pharmacological activities, such as anticancer properties, and the potential for treating neurodegenerative diseases including Alzheimer's disease. Crocins are mainly biosynthesized in the stigmas of food-medicine herbs Crocus sativus L. and Gardenia jasminoides fruits. The distribution is narrow in nature and deficient in resources, which are scarce and expensive. Recently, the synthesis of metabolites in the heterologous host has opened up the potential for large-scale and sustainable production of crocins, especially for the main active compounds crocin I and crocin II. In this study, GjCCD4a, GjALDH2C3, GjUGT74F8, and GjUGT94E13 from G. jasminoides fruits were expressed in Nicotiana benthamiana. The highest total content of crocins in T1 generation tobacco can reach 78,362 ng/g FW (fresh weight) and the dry weight is expected to reach 1,058,945 ng/g DW (dry weight). Surprisingly, the primary effective constituents crocin I and crocin II can account for 99% of the total crocins in transgenic plants. The strategy mentioned here provides an alternative platform for the scale-up production of crocin I and crocin II in tobacco.


Assuntos
Doença de Alzheimer , Nicotiana , Nicotiana/genética , Carotenoides , Frutas
6.
Geriatrics (Basel) ; 8(5)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37736893

RESUMO

This aim of this research was to explore the appraisal of the use of smart alert bracelets by older adults diagnosed with dementia. Convenience sampling was adopted to recruit older adults with dementia in Yunlin County, Taiwan. A manual questionnaire survey was conducted, and SPSS 26.0 statistical software was used for analysis. The results of this study showed noticeable positive correlation results in the post-test for the modes "wearing device", "degree of dementia", and "field configuration". Based on the experimental results, the following suggestions are provided: (1) in terms of statistical calculation, the statistical results were affected by changes in some participants; (2) as for the design of equipment, to be more suitable for adult use, the size and color of bracelets need to be optimized; (3) as for the problem of battery charging of the device, because the charging location of the device is not easy to find, it is better to extend device standby time; (4) regarding the selection of equipment, older adults with early-stage dementia could be concerned about the function of the wearable device, so it is recommended to provide a device designed with clear functions, such as a watch, so that older adults are more willing to wear it. Patients diagnosed with moderate and severe dementia should be advised to use concealed non-sensory devices, such as charms and cards, to better facilitate assistance from caregivers in wearing them; and (5) as for the device, in case of a loss event, in addition to mobile phone notifications, other light and sound device notifications can be added, allowing caregivers to pay more attention to information in real time. In summary, the feedback from caregivers and older adults suggests that if the device is to be used without charging, the overall design should be light and small, which is more suitable for service designs.

8.
PLoS One ; 18(6): e0286645, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37267296

RESUMO

This study aimed to compare the intrinsic foot muscle (IFM) morphology and isometric strength among runners with habitual rearfoot strike (RFS) and non-rearfoot strike (NRFS) patterns. A total of 70 recreational male runners were included in this study (32 RFS and 38 NRFS), an ultrasound device and hand-held dynamometry were used to measure IFM morphology and isometric strength. Results indicated that the RFS runners had significantly thicker tibialis anterior (P = 0.01, ES = 0.64, 95% CI [0.01-0.07]) in IFMs morphology and higher Toe2345 flexion strength in IFMs strength (P = 0.04, ES = 0.50, 95% CI [0.01-0.27]) than NRFS runners, the cross-sectional area of flexor digitorum brevis was positively correlated with T2345 flexion strength (r = 0.33, p = 0.04), T12345 (r = 0.37, p = 0.02) and Doming (r = 0.36, p = 0.03) for runners with NRFS. IFMs morphology and isometric strength were associated with foot strike pattern, preliminary findings provide new perspectives for NRFS runners through the simple measurement of IFMs morphological characteristics predicting IFMs strength, future studies could adopt IFMs training to compensate the muscle strength defects and prevent foot-related injuries.


Assuntos
Corrida , Masculino , Humanos , Corrida/fisiologia , Pé/fisiologia , Extremidade Inferior , Músculo Esquelético/fisiologia , Fenômenos Biomecânicos , Marcha/fisiologia
9.
PLoS One ; 18(6): e0287689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37368906

RESUMO

OBJECTIVE: This study aimed to examine the effects of plantar-sensory treatments on postural control in individuals with chronic ankle instability (CAI). METHODS: This study was registered in PROSPERO (registration number CRD42022329985) on May 14, 2022. An extensive search was performed in Pubmed, Embase, Cochrane, Web of Science, and Scopus to identify the potential studies on plantar-sensory treatments affecting postural control before May 2022. The methodological quality of involved studies was assessed using the scale of Physiotherapy Evidence Database (PEDro). The Cochrane Tool and the Risk of Bias in Non-randomized Studies of Interventions assessment tool were used to evaluate the risk of bias in randomised controlled trials (RCTs) and non-RCTs respectively. RevMan 5.4 was utilised to calculate the standardised mean difference (SMD), with 95% confidence interval (CI). RESULTS: Eight RCTs with a mean PEDro rating of 6 and four non-RCTs with a mean PEDro rating of 4.75 were included in the quantitative analysis. The types of plantar-sensory treatments included plantar massage, whole-body vibration and textured surface-stimulation treatment. A significant effect of static balance with eyes open (SMD = -0.54; 95% CI: -0.81 to -0.27; p < 0.001) was found and subgroup analysis showed that plantar massage (SMD = -0.49; 95% CI: -0.84 to -0.14; p = 0.006) and whole-body vibration (SMD = -0.66; 95% CI: -1.12 to -0.19; p = 0.005) had positive effects. In the subgroup analysis of anterior dynamic balance, whole-body vibration revealed a significant increase (SMD = 0.60; 95% CI: 0.06-1.14; p = 0.03). The pooled results or subgroup analysis including eyes-closed static balance and other directions of dynamic balance indicated no significant difference (p > 0.05). CONCLUSIONS: This meta-analysis indicated that plantar-sensory treatments could improve postural control in CAI, especially the treatments of plantar massage and long-term whole-body vibration.


Assuntos
Tornozelo , Instabilidade Articular , Humanos , Instabilidade Articular/terapia , Modalidades de Fisioterapia , Equilíbrio Postural/fisiologia , Articulação do Tornozelo
10.
Commun Biol ; 6(1): 191, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36805532

RESUMO

Mogrosides are widely used as high-value natural zero-calorie sweeteners that exhibit an array of biological activities and allow for vegetable flavour breeding by modern molecular biotechnology. In this study, we developed an In-fusion based gene stacking strategy for transgene stacking and a multi-gene vector harbouring 6 mogrosides biosynthesis genes and transformed it into Cucumis sativus and Lycopersicon esculentum. Here we show that transgenic cucumber can produce mogroside V and siamenoside I at 587 ng/g FW and 113 ng/g FW, respectively, and cultivated transgenic tomato with mogroside III. This study provides a strategy for vegetable flavour improvement, paving the way for heterologous biosynthesis of mogrosides.


Assuntos
Cucumis sativus , Solanum lycopersicum , Animais , Cucumis sativus/genética , Solanum lycopersicum/genética , Melhoramento Vegetal , Biotecnologia , Animais Geneticamente Modificados
11.
Plant Sci ; 326: 111506, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36283577

RESUMO

Dandelion is a well-known traditional medical herb, also used as functional food. Dandelion possesses many medical properties, such as anti-bacterial and antioxidant activity and contains a variety of triterpenes, such as α-amyrin, ß-amyrin, taraxerol and taraxasterol. In this study, we found that triterpenes biosynthesis was promoted by methyl jasmonate (MeJA), while the transcriptional mechanism underlying triterpenes biosynthesis was rarely investigated. Here, a MeJA-induced bHLH transcription factor TaMYC2 was identified. The content of taraxasterol and taraxerol in dandelion was obviously enhanced in overexpression TaMYC2 transgenic lines and expression level of the squalene synthase gene (TaSS) was elevated to about 3-5 folds compared with the control lines. Dual-LUC, Y1H and EMSA experiments revealed that TaMYC2 bound to the E-box motif in the promoter of TaSS and activated its transcription. Taken together, this study suggested that TaMYC2 acted as a positive regulator for bioengineering approaches to produce high content triterpenes-producing dandelions.


Assuntos
Taraxacum , Triterpenos , Taraxacum/genética , Taraxacum/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Triterpenos/metabolismo
12.
Molecules ; 27(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36557779

RESUMO

Sinomenine is the main component of the vine Sinomenium acutum. It was first isolated in the early 1920s and has since attracted special interest as a potential anti-rheumatoid arthritis (RA) agent, owing to its successful application in traditional Chinese medicine for the treatment of neuralgia and rheumatoid diseases. In the past few decades, significant advances have broadened our understanding of the molecular mechanisms through which sinomenine treats RA, as well as the structural modifications necessary for improved pharmacological activity. In this review, we summarize up-to-date reports on the pharmacological properties of sinomenine in RA treatment, document their underlying mechanisms, and provide an overview of promising sinomenine derivatives as potential RA drug therapies.


Assuntos
Artrite Reumatoide , Morfinanos , Neuralgia , Humanos , Artrite Reumatoide/tratamento farmacológico , Morfinanos/uso terapêutico , Morfinanos/farmacologia , Medicina Tradicional Chinesa , Neuralgia/tratamento farmacológico
13.
Int J Mol Sci ; 23(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36142335

RESUMO

Mogrosides are a group of health-promoting natural products that extracted from Siraitia grosvenorii fruit (Luo-han-guo or monk fruit), which exhibited a promising practical application in natural sweeteners and pharmaceutical development. However, the production of mogrosides is inadequate to meet the need worldwide, and uneconomical synthetic chemistry methods are not generally recommended for structural complexity. To address this issue, an in-fusion based gene stacking strategy (IGS) for multigene stacking has been developed to assemble 6 mogrosides synthase genes in pCAMBIA1300. Metabolic engineering of Nicotiana benthamiana and Arabidopsis thaliana to produce mogrosides from 2,3-oxidosqualene was carried out. Moreover, a validated HPLC-MS/MS method was used for the quantitative analysis of mogrosides in transgenic plants. Herein, engineered Arabidopsis thaliana produced siamenoside I ranging from 29.65 to 1036.96 ng/g FW, and the content of mogroside III at 202.75 ng/g FW, respectively. The production of mogroside III was from 148.30 to 252.73 ng/g FW, and mogroside II-E with concentration between 339.27 and 5663.55 ng/g FW in the engineered tobacco, respectively. This study provides information potentially applicable to develop a powerful and green toolkit for the production of mogrosides.


Assuntos
Arabidopsis , Produtos Biológicos , Cucurbitaceae , Triterpenos , Arabidopsis/genética , Arabidopsis/metabolismo , Produtos Biológicos/metabolismo , Cucurbitaceae/genética , Engenharia Metabólica , Edulcorantes , Espectrometria de Massas em Tandem , Triterpenos/química
14.
Materials (Basel) ; 15(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35955195

RESUMO

The possibility of using commercial bayberry tannin (BT) from a Chinese source as a cross-linker and functional additive to develop soybean protein isolate (SPI)-based films was explored in this study by using the solvent casting method. In particular, the impacts of BT loading on the tensile strength, microstructure, thermal stability, water resistance and antioxidant capacity were fully investigated. The results reveal that SPI incorporated with BT yielded a phenolic-protein hybrid whose relevant films exhibited an improvement in tensile strength of around two times greater compared with native SPI as a result of the formed interactions and covalent cross-links, which could be proven using FTIR spectroscopy. The introduction of BT also led to the compact microstructure of SPI-BT films and enhanced the thermal stability, while the water vapor permeability was reduced compared with the control SPI film, especially at high loading content of tannin. Additionally, the use of BT significantly promoted the antioxidant capacity of the SPI-based films according to DPPH radical scavenging assay results. On this basis, Chinese bayberry tannin is considered a promising natural cross-linker and multifunctional additive that can be dedicated to developing protein-derived films with antioxidant activity for food packaging applications.

15.
Molecules ; 27(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35630564

RESUMO

Baicalein is a valuable flavonoid isolated from the medicinal plant Scutellaria baicalensis Georgi, which exhibits intensive biological activities, such as anticancer and antiviral activities. However, its production is limited in the root with low yield. In this study, In-Fusion and 2A peptide linker were developed to assemble SbCLL-7, SbCHI, SbCHS-2, SbFNSII-2 and SbCYP82D1.1 genes driven by the AtPD7, CaMV 35S and AtUBQ10 promoters with HSP, E9 and NOS terminators, and were used to engineer baicalein biosynthesis in transgenic tomato plants. The genetically modified tomato plants with this construct synthesized baicalein, ranging from 150 ng/g to 558 ng/g FW (fresh weight). Baicalein-fortified tomatoes have the potential to be health-promoting fresh vegetables and provide an alternative source of baicalein production, with great prospects for market application.


Assuntos
Flavanonas , Solanum lycopersicum , Flavonoides , Solanum lycopersicum/genética , Scutellaria baicalensis
16.
Zhongguo Zhong Yao Za Zhi ; 46(17): 4403-4409, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581043

RESUMO

This study aims to explore the pharmacodynamic differences of Puerariae Lobatae Radix(PLR), Puerariae Thomsonii Radix(PTR) and their different processed products and the influences of these medical materials on the diversity of intestinal flora. The Sennae Folium-induced diarrhea model, streptozotocin(STZ)-induced diabetes model and L-nitro-arginine methyl ester(L-NAME)-induced hypertension model were used to compare the pharmacodynamic differences in anti-diarrhea, blood glucose reduction and blood pressure lowering among raw, roasted and vinegar-processed PLR and PTR. The effects of raw and processed PLR and PTR on intestinal flora diversity of rats were evaluated by 16 S rDNA high-throughput sequencing. The roasted PLR and PTR performed better in anti-diarrhea, especially the former. PLR and its processed products all presented the efficacy of reducing blood glucose, and the vinegar-processed PLR was the most outstanding. The raw PTR was not that effective in reducing blood glucose, whereas its efficacy was improved after roasting and vinegar processing. Both PLR and PTR were capable of lowering blood pressure to a certain extent, and PLR is superior to PTR in this aspect. Further, the vinegar-processed PLR showed the best effect. The diversity of intestinal flora was different among rats to which different products of PLR and PTR were administered. The roasted PLR led to the highest abundance of Lactobacillus, which was closely related to its best antidiarrheal effect. The highest abilities of vinegar-processed PLR to lower blood glucose and blood pressure were associated with the high abundance of Blautia and Prevotella_9. This study lays a foundation for elucidating the processing mechanisms of PLR and PTR and provides a basis for their further development and application.


Assuntos
Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Pueraria , Animais , Raízes de Plantas , Ratos
17.
Phytochemistry ; 189: 112824, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34102591

RESUMO

Siraitia grosvenorii (Luo hanguo or monk fruit) is a valuable medicinal herb for which the market demand has increased dramatically worldwide. As promising natural sweeteners, mogrosides have received much attention from researchers because of their extremely high sweetness and lack of calories. Nevertheless, owing to the absence of genetic transformation methods, the molecular mechanisms underlying the regulation of mogroside biosynthesis have not yet been fully elucidated. Therefore, an effective method for gene function analysis needs to be developed for S. grosvenorii fruit. As a powerful approach, transient expression has become a versatile method to elucidate the biological functions of genes and proteins in various plant species. In this study, PBI121 with a ß-glucuronidase (GUS) marker and tobacco rattle virus (TRV) were used as vectors for overexpression and silencing, respectively, of the SgCPR1 and SgCPR2 genes in S. grosvenorii fruit. The effectiveness of transient expression was validated by GUS staining in S. grosvenorii fruit, and the expression levels of SgCPR1 and SgCPR2 increased significantly after infiltration for 36 h. In addition, TRV-induced gene silencing suppressed the expression of SgCPR1 and SgCPR2 in S. grosvenorii fruit. More importantly, the production of the major secondary metabolites mogrol, mogroside IIE (MIIE) and mogroside III (MIII) was activated by the overexpression of SgCPR1 and SgCPR2 in S. grosvenorii fruit, with levels 1-2 times those in the control group. Moreover, the accumulation of mogrol, MIIE and MIII was decreased in the SgCPR1 and SgCPR2 gene silencing assays. Therefore, this transient expression approach was available for S. grosvenorii fruit, providing insight into the expression of the SgCPR1 and SgCPR2 genes involved in the mogroside biosynthesis pathway. Our study also suggests that this method has potential applications in the exploration of the molecular mechanisms, biochemical hypotheses and functional characteristics of S. grosvenorii genes.


Assuntos
Cucurbitaceae , Triterpenos , Cucurbitaceae/genética , Sistema Enzimático do Citocromo P-450 , Frutas/genética , NADP , NADPH-Ferri-Hemoproteína Redutase
18.
Gene ; 769: 145210, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069807

RESUMO

Nonexpressor of pathogenesis-related (NPR) genes are bona fide transcription cofactors in the signal transduction pathway of salicylic acid (SA) and play critical regulatory roles in plant immunity. However, the NPR family genes in Brassica juncea var. tumida have not yet been comprehensively identified and analyzed as of yet. In the present study, NPR genes in B. juncea var. tumida seedlings were identified, and the tissue-specific expression patterns of NPR genes in the seedling were analyzed under salt stress (200 mM) treatment and infection by Plasmodiophora brassicae. A total of 19 NPR family genes clustering into six separate groups were identified in the genome of B. juncea var. tumida. These BjuNPR family genes were located in 11 of 18 chromosomes of B. juncea var. tumida and each possessed 1-5 exons. The BjuNPR family members had similar protein structures and conserved motifs. The BjuNPR genes exhibited tissue-specific expression patterns in the root, stem, leaf, flower and pod. Some BjuNPR genes were sensitive to salt stress and showed up-regulated or down-regulated expression patterns and most BjuNPR genes were up-regulated upon infection by P. brassicae. This study provides a foundation for further research into BjuNPR genes regulation in plant growth, development, and abiotic stress tolerance.


Assuntos
Brassica/genética , Genoma de Planta , Família Multigênica , Sequência de Aminoácidos , Brassica/fisiologia , Cromossomos de Plantas , Perfilação da Expressão Gênica , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Estruturas Vegetais/genética , Regiões Promotoras Genéticas , Ácido Salicílico/metabolismo , Estresse Salino , Homologia de Sequência de Aminoácidos
19.
Sci Rep ; 10(1): 17452, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060707

RESUMO

Drought stress severely impairs plant growth and production. Lipoxygenase (LOX), a master regulator for lipid peroxidation, is critical for direct or indirect response to abiotic stresses. Here, we found that drought stress induced the transcription of CmLOX10 in leaves of oriental melon seedlings. Reverse genetic approaches and physiological analyses revealed that silencing CmLOX10 increased drought susceptibility and stomatal aperture in oriental melon seedlings, and that ectopic overexpression of CmLOX10 in Arabidopsis enhanced drought tolerance and decreased the stomatal aperture. Moreover, the transcription of jasmonic acid (JA)-related genes and JA accumulation were significantly induced in CmLOX10-overexpressed Arabidopsis, which were reversely suppressed in CmLOX10-silenced seedlings during the stage of drought stress. Foliar application of JA further verified that JA enhanced drought tolerance and induced stomatal closure in leaves of melon seedlings. In addition, the feedback regulation of CmLOX10 was induced by JA signaling, and the expression level of CmMYC2 was increased by JA and drought treatment. Yeast one-hybrid analysis showed that CmMYC2 directly bound to the promoter of CmLOX10. In summary, we identified the important roles of CmLOX10 in the regulation of drought tolerance in oriental melon seedlings through JA- mediated stomatal closure and JA signaling-mediated feedback through CmMYC2.


Assuntos
Cucumis melo/efeitos dos fármacos , Ciclopentanos/farmacologia , Lipoxigenase/metabolismo , Oxilipinas/farmacologia , Estômatos de Plantas/metabolismo , Ácido Abscísico/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Cucumis melo/fisiologia , Secas , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Malondialdeído/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/fisiologia , Transdução de Sinais , Estresse Fisiológico , Transcriptoma
20.
J Biol Chem ; 295(50): 17083-17099, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33033071

RESUMO

Reactive oxygen species (ROS) are an unavoidable host environmental cue for intracellular pathogens such as Mycobacterium tuberculosis and Mycobacterium bovis; however, the signaling pathway in mycobacteria for sensing and responding to environmental stress remains largely unclear. Here, we characterize a novel CmtR-Zur-ESX3-Zn2+ regulatory pathway in M. bovis that aids mycobacterial survival under oxidative stress. We demonstrate that CmtR functions as a novel redox sensor and that its expression can be significantly induced under H2O2 stress. CmtR can physically interact with the negative regulator Zur and de-represses the expression of the esx-3 operon, which leads to Zn2+ accumulation and promotion of reactive oxygen species detoxication in mycobacterial cells. Zn2+ can also act as an effector molecule of the CmtR regulator, using which the latter can de-repress its own expression for further inducing bacterial antioxidant adaptation. Consistently, CmtR can induce the expression of EsxH, a component of esx-3 operon involved in Zn2+ transportation that has been reported earlier, and inhibit phagosome maturation in macrophages. Lastly, CmtR significantly contributes to bacterial survival in macrophages and in the lungs of infected mice. Our findings reveal the existence of an antioxidant regulatory pathway in mycobacteria and provide novel information on stress-triggered gene regulation and its association with host-pathogen interaction.


Assuntos
Proteínas de Bactérias/metabolismo , Viabilidade Microbiana , Mycobacterium bovis/metabolismo , Estresse Oxidativo , Fatores de Transcrição/metabolismo , Zinco/metabolismo , Proteínas de Bactérias/genética , Mycobacterium bovis/genética , Fatores de Transcrição/genética
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