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1.
Plant Physiol ; 191(1): 265-279, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36047837

RESUMO

Cell cycle progression and the phytohormones auxin and abscisic acid (ABA) play key roles in primary root growth, but how ABA mediates the transcription of cell cycle-related genes and the mechanism of crosstalk between ABA and auxin requires further research. Here, we report that ABA inhibits primary root growth by regulating the ABA INSENSITIVE4 (ABI4)-CYCLIN-DEPENDENT KINASE B2;2 (CDKB2;2)/CYCLIN B1;1 (CYCB1;1) module-mediated cell cycle as well as auxin biosynthesis in Arabidopsis (Arabidopsis thaliana). ABA induced ABI4 transcription in the primary root tip, and the abi4 mutant showed an ABA-insensitive phenotype in primary root growth. Compared with the wild type (WT), the meristem size and cell number of the primary root in abi4 increased in response to ABA. Further, the transcription levels of several cell-cycle positive regulator genes, including CDKB2;2 and CYCB1;1, were upregulated in abi4 primary root tips. Subsequent chromatin immunoprecipitation (ChIP)-seq, ChIP-qPCR, and biochemical analysis revealed that ABI4 repressed the expression of CDKB2;2 and CYCB1;1 by physically interacting with their promoters. Genetic analysis demonstrated that overexpression of CDKB2;2 or CYCB1;1 fully rescued the shorter primary root phenotype of ABI4-overexpression lines, and consistently, abi4/cdkb2;2-cr or abi4/cycb1;1-cr double mutations largely rescued the ABA-insensitive phenotype of abi4 with regard to primary root growth. The expression levels of DR5promoter-GFP and PIN1promoter::PIN1-GFP in abi4 primary root tips were significantly higher than those in WT after ABA treatment, with these changes being consistent with changes in auxin concentration and expression patterns of auxin biosynthesis genes. Taken together, these findings indicated that ABA inhibits primary root growth through ABI4-mediated cell cycle and auxin-related regulatory pathways.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Divisão Celular , Ácidos Indolacéticos/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Cytokine ; 173: 156446, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979213

RESUMO

OBJECTIVES: Previous studies have reported an association between inflammatory cytokines and inflammatory arthritis, including Ankylosing spondylitis (AS), rheumatoid arthritis (RA), and psoriatic arthritis (PsA). This study aims to explore the causal relationship between inflammatory cytokines and AS, RA, and PsA using Mendelian randomization (MR). METHODS: We conducted a bidirectional two-sample MR analysis using genetic summary data from a publicly available genome-wide association study (GWAS) that included 41 genetic variations of inflammatory cytokines, as well as genetic variant data for AS, RA, and PsA from the FinnGen consortium. The main analysis method used was Inverse variance weighted (IVW) to investigate the causal relationship between exposure and outcome. Additionally, other methods such as MR Egger, weighted median (WM), simple mode, and weighted mode were employed to strengthen the final results. Sensitivity analysis was also performed to ensure the reliability of the findings. RESULTS: The results showed that macrophage colony-stimulating factor (MCSF) was associated with an increased risk of AS (OR = 1.163, 95 % CI = 1.016-1.33, p = 0.028). Conversely, high levels of TRAIL and beta nerve growth factor (ß-NGF) were associated with a decreased risk of AS (OR = 0.892, 95 % CI = 0.81-0.982, p = 0.002; OR = 0.829, 95 % CI = 0.696-0.988, p = 0.036). Four inflammatory cytokines were found to be associated with an increased risk of PsA: vascular endothelial growth factor (VEGF) (OR = 1.161, 95 % CI = 1.057-1.275, p = 0.002); Interleukin 12p70 (IL12p70) (OR = 1.189, 95 % CI = 1.049-1.346, p = 0.007); IL10 (OR = 1.216, 95 % CI = 1.024-1.444, p = 0.026); IL13 (OR = 1.159, 95 % CI = 1.05-1.28, p = 0.004). Interleukin 1 receptor antagonist (IL-1rα) was associated with an increased risk of seropositive RA (OR = 1.181, 95 % CI = 1.044-1.336, p = 0.008). Similarly, genetic susceptibility to inflammatory arthritis was found to be causally associated with multiple inflammatory cytokines. Lastly, the sensitivity analysis supported the robustness of these findings. CONCLUSIONS: This study provides additional insights into the relationship between inflammatory cytokines and inflammatory arthritis, and may offer new clues for the etiology, diagnosis, and treatment of inflammatory arthritis.


Assuntos
Artrite Psoriásica , Artrite Reumatoide , Espondilite Anquilosante , Humanos , Citocinas/genética , Artrite Psoriásica/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Reprodutibilidade dos Testes , Fator A de Crescimento do Endotélio Vascular , Artrite Reumatoide/genética , Espondilite Anquilosante/genética
3.
J Integr Plant Biol ; 66(5): 909-927, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38328870

RESUMO

Transcriptional regulation plays a key role in the control of seed dormancy, and many transcription factors (TFs) have been documented. However, the mechanisms underlying the interactions between different TFs within a transcriptional complex regulating seed dormancy remain largely unknown. Here, we showed that TF PHYTOCHROME-INTERACTING FACTOR4 (PIF4) physically interacted with the abscisic acid (ABA) signaling responsive TF ABSCISIC ACID INSENSITIVE4 (ABI4) to act as a transcriptional complex to promote ABA biosynthesis and signaling, finally deepening primary seed dormancy. Both pif4 and abi4 single mutants exhibited a decreased primary seed dormancy phenotype, with a synergistic effect in the pif4/abi4 double mutant. PIF4 binds to ABI4 to form a heterodimer, and ABI4 stabilizes PIF4 at the protein level, whereas PIF4 does not affect the protein stabilization of ABI4. Subsequently, both TFs independently and synergistically promoted the expression of ABI4 and NCED6, a key gene for ABA anabolism. The genetic evidence is also consistent with the phenotypic, physiological and biochemical analysis results. Altogether, this study revealed a transcriptional regulatory cascade in which the PIF4-ABI4 transcriptional activator complex synergistically enhanced seed dormancy by facilitating ABA biosynthesis and signaling.


Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Dormência de Plantas , Transdução de Sinais , Fatores de Transcrição , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Dormência de Plantas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ligação Proteica , Sementes/metabolismo , Sementes/genética , Mutação/genética
4.
BMC Immunol ; 24(1): 32, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752439

RESUMO

BACKGROUND: HLA-B27 positivity is normal in patients undergoing rheumatic diseases. The diagnosis of many diseases requires an HLA-B27 examination. METHODS: This study screened totally 1503 patients who underwent HLA-B27 examination, liver/kidney function tests, and complete blood routine examination in First Affiliated Hospital of Guangxi Medical University. The training cohort included 509 cases with HLA-B27 positivity whereas 611 with HLA-B27 negativity. In addition, validation cohort included 147 cases with HLA-B27 positivity whereas 236 with HLA-B27 negativity. In this study, 3 ML approaches, namely, LASSO, support vector machine (SVM) recursive feature elimination and random forest, were adopted for screening feature variables. Subsequently, to acquire the prediction model, the intersection was selected. Finally, differences among 148 cases with HLA-B27 positivity and negativity suffering from ankylosing spondylitis (AS) were investigated. RESULTS: Six factors, namely red blood cell count, human major compatibility complex, mean platelet volume, albumin/globulin ratio (ALB/GLB), prealbumin, and bicarbonate radical, were chosen with the aim of constructing the diagnostic nomogram using ML methods. For training queue, nomogram curve exhibited the value of area under the curve (AUC) of 0.8254496, and C-value of the model was 0.825. Moreover, nomogram C-value of the validation queue was 0.853, and the AUC value was 0.852675. Furthermore, a significant decrease in the ALB/GLB was noted among cases with HLA-B27 positivity and AS cases. CONCLUSION: To conclude, the proposed ML model can effectively predict HLA-B27 and help doctors in the diagnosis of various immune diseases.


Assuntos
Antígeno HLA-B27 , Nomogramas , Humanos , Antígeno HLA-B27/genética , China , Fígado , Aprendizado de Máquina
5.
New Phytol ; 232(2): 692-704, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34254312

RESUMO

Plants absorb sulfur from the environment and assimilate it into suitable forms for the biosynthesis of a broad range of molecules. Although the biochemical pathway of sulfur assimilation is known, how genetic differences contribute to natural variation in sulfur assimilation remains poorly understood. Here, using a genome-wide association study, we uncovered a single-nucleotide polymorphism (SNP) variant in the sulfite reductase (SiR) gene that was significantly associated with SiR protein abundance in a maize natural association population. We also demonstrated that the synonymous C to G base change at SNP69 may repress translational activity by altering messenger RNA secondary structure, which leads to reduction in ZmSiR protein abundance and sulfur assimilation activity. Population genetic analyses showed that the SNP69C allele was likely a variant occurring after the initial maize domestication and accumulated with the spread of maize cultivation from tropical to temperate regions. This study provides the first evidence that genetic polymorphisms in the exon of ZmSiR could influence the protein abundance through a posttranscriptional mechanism and in part contribute to natural variation in sulfur assimilation. These findings provide a prospective target to improve maize varieties with proper sulfur nutrient levels assisted by molecular breeding and engineering.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos Prospectivos , Enxofre , Zea mays/genética
6.
Bioorg Med Chem ; 27(20): 114969, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31262665

RESUMO

Computer-aided drug design has advanced by leaps and bounds, and has been widely used in various fields, and especially in the field of drug discovery. Although the crystal structure of the gibberellin (GA) receptor GID1A had been reported in previous studies, there is still a lack of designs of gibberellin functional analogue based GID1A. In the present study, a series of 30 thiourea derivatives were designed, synthesized and biologically assayed. The results suggested that the synthetic compounds had good GA-like activities. Furthermore, the structure-activity relationship of the synthetic compounds was discussed, and the dynamic simulation and docking study revealed the binding properties of the GID1A receptor and compounds Y1, Y11, and Y21.


Assuntos
Arabidopsis/efeitos dos fármacos , Desenho de Fármacos , Giberelinas/farmacologia , Simulação de Dinâmica Molecular , Tioureia/farmacologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Relação Dose-Resposta a Droga , Giberelinas/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Relação Estrutura-Atividade , Tioureia/análogos & derivados , Tioureia/química
7.
Pestic Biochem Physiol ; 143: 265-271, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29183603

RESUMO

Glutathione S-transferases (GSTs) have been widely studied in relation to their role in herbicide tolerance and detoxification. However, a detailed characterization of GSTs from herbicide tolerant and sensitive maize cultivars is still lacking. In this study, we determined the mechanism of differential tolerance between two maize cultivars which had 4-fold difference tolerance to metolachlor. The metabolism rate of metolachlor was more rapid in the tolerant cultivar (Zea mays L. cv Nongda86) than the susceptible one (Zea mays L. cv Zhengda958). Addition of the GST inhibitor ethacrynic acid reduced the metabolism of metolachlor indicating the involvement of GSTs in the differential detoxification of metolachlor. The expression profiles of 32 GST isozymes were measured using quantitative RT-PCR. The results showed the expression of GST genes were slightly up-regulated in Nongda86, but severely inhibited in Zhengdan958 24h after metolachlor treatment. The genes GSTI, GSTIII, GSTIV, GST5, GST6 and GST7, which can detoxify chloroacetanilide herbicides, were all expressed higher in Nongda86 compared to Zhendgan958. The result of GST activity was consistent with the gene expression profiles. Collectively, higher-level expression of GST genes, leading to higher GST activity and faster herbicide detoxification, appears to be responsible for the difference in tolerance to metolachlor in two maize cultivars.


Assuntos
Acetamidas/toxicidade , Glutationa Transferase/genética , Resistência a Herbicidas/genética , Herbicidas/toxicidade , Zea mays/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Inativação Metabólica , Isoenzimas/genética , Proteínas de Plantas/genética , Especificidade da Espécie , Zea mays/genética
8.
Molecules ; 22(5)2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28445402

RESUMO

A series of novel C-3-OH substituted gibberellin derivatives bearing an amide group were designed and synthesized from the natural product gibberellic acid (GA3). Their activities on the plant growth regulation of rice and Arabidopsis were evaluated in vivo. Among these compounds, 10d and 10f exhibited appreciable inhibitory activities on rice (48.6% at 100 µmol/L) and Arabidopsis (41.4% at 100 µmol/L), respectively. These results provide new insights into the design and synthesis of potential plant growth regulators.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Giberelinas/farmacologia , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/farmacologia , Arabidopsis/efeitos dos fármacos , Cristalografia por Raios X , Giberelinas/síntese química , Oryza/efeitos dos fármacos
9.
Anal Chem ; 84(10): 4327-33, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22494059

RESUMO

Ginsenoside Re (GRe) is a major active component of the Chinese medicinal herb ginseng, Panax ginseng . A sensitive and specific monoclonal antibody (mAb), designated as mAb3D6, was generated with a GRe-bovine serum albumin conjugate as an immunogen. Microcantilever immunosensors (MCS), one modified with thiolated anti-GRe antibody and one modified with thiolated goat antimouse immunoglobulin G (IgG), were developed to detect the content of ginsenoside. The MCS immobilized with thiolated goat antimouse IgG had a better sensitivity than the MCS modified with thiolated anti-GRe antibody. The advantage of a secondary antibody thio-functionalized MCS was verified with the anti-paclitaxel mAb. An indirect competitive enzyme-linked immunosorbent assay (icELISA) was also established with mAb3D6. The concentration of analyte producing 50% inhibition and the working range of icELISA were 1.20 and 0.15-16.1 ng/mL, respectively. The icELISA had a cross-reactivity of 89% with ginsenoside Rg1 and less than 3% with other ginsenosides. The icELISA and MCS with thiolated secondary antibody were applied for the determination of GRe in ginseng samples, and the results agreed well with those determined by high-performance liquid chromatography.


Assuntos
Anticorpos Monoclonais/imunologia , Ensaio de Imunoadsorção Enzimática , Ginsenosídeos/análise , Panax/química , Animais , Anticorpos Monoclonais/química , Bovinos , Feminino , Ginsenosídeos/imunologia , Cabras , Haptenos/química , Haptenos/imunologia , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Soroalbumina Bovina/química , Soroalbumina Bovina/imunologia , Compostos de Sulfidrila/química
10.
Front Plant Sci ; 13: 916287, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36237496

RESUMO

Salinity severely inhibits growth and reduces yield of salt-sensitive plants like wheat, and this effect can be alleviated by plant growth regulators and phytohormones, among which abscisic acid (ABA) plays a central role in response to various stressful environments. ABA is highly photosensitive to light disruption, which this limits its application. Here, based on pyrabactin (a synthetic ABA agonist), we designed and synthesized a functional analog of ABA and named B2, then evaluated its role in salt resistance using winter wheat seedlings. The phenotypes showed that B2 significantly improved the salt tolerance of winter wheat seedlings by elevating the biomass. The physiological analysis found that B2 treatment reduced the generation rate of O2 -, electrolyte leakage, the content of proline, and the accumulation of malonaldehyde (MDA) and H2O2 and also significantly increased the contents of endogenous hormones zeatin riboside (ZA) and gibberellic acid (GA). Further biochemical analysis revealed that the activities of various antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX), were enhanced by B2, and the activities of antioxidase isozymes SOD3, POD1/2, and APX1/2 were particularly increased, largely resembling ABA treatment. The abiotic stress response-related gene TaSOS1 was significantly upregulated by B2, while the TaTIP2;2 gene was suppressed. In conclusion, an ABA analog B2 was capable to enhance salt stress tolerance in winter wheat seedlings by stimulating the antioxidant system, providing a novel regulator for better survival of crops in saline soils and improving crop yield.

11.
Front Plant Sci ; 13: 902902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755644

RESUMO

Deeper and longer roots allow crops to survive and flourish, but our understanding of the plant growth regulators promoting root system establishment is limited. Here, we report that, a novel auxin receptor agonist, named K-10, had a remarkable promotive effect on root growth in both Arabidopsis thaliana and Oryza sativa through the enhancement of root-related signaling responses. Using computer-aided drug discovery approaches, we developed potent lead compound by screening artificial chemicals on the basis of the auxin receptor TIR1 (Transport Inhibitor Response 1), and a series of N-(benzo[d] [1,3] dioxol-5-yl)-2-(one-benzylthio) acetamides, K-1 to K-22, were designed and synthesized. The results of bioassay showed that K-10 exhibited an excellent root growth-promoting activity far exceeding that of NAA (1-naphthylacetic acid). A further morphological investigation of the auxin related mutants (yucQ, tir1) revealed that K-10 had auxin-like physiological functions and was recognized by TIR1, and K-10 significantly enhanced auxin response reporter's (DR5:GUS) transcriptional activity. Consistently, transcriptome analysis showed that K-10 induced a common transcriptional response with auxin and down-regulated the expression of root growth-inhibiting genes. Further molecular docking analysis revealed that K-10 had a stronger binding ability with TIR1 than NAA. These results indicated that this class of derivatives could be a promising scaffold for the discovery and development of novel auxin receptor agonists, and the employment of K-10 may be effective for enhancing root growth and crop production.

12.
Pest Manag Sci ; 77(5): 2252-2263, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33411985

RESUMO

BACKGROUND: Picolinate/picolinic acid compounds are an important class of synthetic auxin herbicides. To explore the herbicidal activity of 6-pyrazolyl picolinate compounds, a series of 3-chloro-6-pyrazolyl-picolinate derivatives was designed and synthesized. RESULTS: Twenty-five 3-chloro-6-pyrazolyl-picolinate derivatives synthesized were tested for herbicidal activity and the IC50 value of compound c5 to the growth of Arabidopsis thaliana root was 27 times lower than that of the commercial herbicide clopyralid. Compound c5 displayed better post-emergence herbicidal activity and broader (Picloram, Clopyralid, Aminopyralid) herbicidal spectrum at a dosage of 400 g ha-1 in comparison with clopyralid; it also was safe to wheat and maize at this dosage. Arabidopsis thaliana phenotypes and expression of auxin-response genes demonstrated that compound c5 might be a novel auxin-type herbicide. Molecular docking analyses revealed that compound c5 had stronger binding ability to receptor AFB5 (auxin signaling F-box protein 5) than clopyralid. CONCLUSION: These 6-pyrazolyl picolinate compounds could be used as potential lead structures for the discovery of a novel synthetic auxin herbicide. © 2021 Society of Chemical Industry.


Assuntos
Arabidopsis , Herbicidas , Arabidopsis/genética , Herbicidas/farmacologia , Simulação de Acoplamento Molecular , Ácidos Picolínicos , Relação Estrutura-Atividade
13.
Anal Chem ; 82(2): 615-20, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19994853

RESUMO

Development of microcantilever biosensors for small molecules was exemplified with the beta-adrenergic agonist clenbuterol and the antibiotic chloramphenicol. In this paper, antibody sulfhydrylation and protein A were used to modify the microcantilever Au surface, and the antibody activities on the microcantilever were evaluated with direct competitive enzyme-linked immunosorbent assay (dcELISA). The activity of the antibodies immobilized on the microcantilever via protein A was 1.7-fold of that via the sulfhydrylation reagent 2-iminothiolane hydrochloride. A microcantilever immunosensor method with protein A as the functionalization reagent was established to detect the residues of clenbuterol and chloramphenicol at limits of detection (LOD) of approximately 0.1 and 0.2 ng/mL, respectively. Such LODs were better than that of the corresponding dcELISAs. The concentration of clenbuterol in a fortified feed sample detected with the microcantilever immunosensor after thorough extraction and purification agreed well with that detected with the dcELISA. Protein A showed to be simple and reproducible for functionalization of the antibodies on the Au surface and, thus, has common application values in microcantilever immunosensor development. The results suggest that microcantilever immunosensors be suitable for detection of small molecules, and the assay sensitivity is mainly related to the quality and activities of the antibodies.


Assuntos
Cloranfenicol/análise , Clembuterol/análise , Ensaio de Imunoadsorção Enzimática/métodos , Proteína Estafilocócica A/química , Anticorpos Imobilizados/imunologia , Anticorpos Imobilizados/metabolismo , Ensaio de Imunoadsorção Enzimática/instrumentação , Ouro/química , Limite de Detecção
14.
Front Microbiol ; 11: 1362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793123

RESUMO

Coronatine (COR) is a new type of plant growth regulator that is produced by Pseudomonas syringae pathovars and plays an important role in modulating plant growth, development, and tolerance to multiple stresses. However, the factors affecting COR production are not very clear. In this study, the effects of FeCl3 on COR production were researched. The data-independent acquisition (DIA) approach, which is a proteomic quantitative analysis method, was applied to quantitatively trace COR production and proteomic changes in P. syringae pv. tomato DC3000 under different FeCl3 culture conditions. The results showed that COR production increased with the addition of FeCl3 and that there was significant upregulation in the expression of proteins related to COR synthesis and regulation. In addition, FeCl3 also affected the expression of related proteins involved in various metabolic pathways such as glycolysis and the tricarboxylic acid cycle. Moreover, various precursors such as isoleucine and succinate semialdehyde, as well as other related proteins involved in the COR synthesis pathway, were significantly differentially expressed. Our findings revealed the dynamic regulation of COR production in response to FeCl3 at the protein level and showed the potential of using the DIA method to track the dynamic changes of the P. syringae pv. tomato DC3000 proteome during COR production, providing an important reference for future research on the regulatory mechanism of COR biosynthesis and theoretical support for COR fermentation production.

15.
Pest Manag Sci ; 76(2): 807-817, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31400044

RESUMO

BACKGROUND: The use of exo-16,17-dihydro-gibberellin A5-13-acetate (DHGA5 ) in agriculture has been limited by its low synthetic yield. This study was aimed at optimizing the synthetic route of DHGA5 , designing and synthesizing new derivatives with strong plant growth inhibitory activities. RESULTS: Previous synthetic methods were replaced with a shorter, milder and faster reaction route with higher yield (76.3%) of DHGA5 . Based on this novel route, a series of new derivatives were designed and synthesized using DHGA5 as a lead compound and characterized and evaluated for biological activities in Arabidopsis thaliana. Among the 15 tested derivatives, compound 14j showed a lower medium inhibition concentration (IC50 , 73 µm) in Arabidopsis than that of DHGA5 (91 µm). Gibberellin deficient mutant assay further revealed that 14j had very different activities compared to DHGA5 as it specifically inhibits gibberellin biosynthetic pathways. In addition, 14j does not influence the interaction between gibberellin receptors (GID1) and the master growth repressor (RGA) based on yeast two-hybrid assay. CONCLUSION: The optimized synthetic route provides a promising method for large-scale preparation of DHGA5 . Our biological assays indicate that 14j likely acts on gibberellin signaling elements other than GID1. These results indicate that novel plant growth regulators can be developed. © 2019 Society of Chemical Industry.


Assuntos
Arabidopsis , Acetatos , Proteínas de Arabidopsis , Regulação da Expressão Gênica de Plantas , Giberelinas , Reguladores de Crescimento de Plantas
16.
J Agric Food Chem ; 68(28): 7360-7368, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32627551

RESUMO

Lignin is the most abundant aromatic biopolymer in nature and is a major byproduct from the paper industry. The unlocking of lignin's potential for high-value applications has gained increasing attention in recent years. In this study, alkali lignin (AL), with a rigid conjugated structure and amphiphilic property, was used as a sustainable and eco-friendly encapsulation material for the protection and controlled release of photosensitive abscisic acid (ABA), an important and widely used plant growth regulator. Cetyltrimethylammonium bromide (CTAB) was used to induce the formation of AL-CTAB nanomicroparticles by self-assembly. The size and morphology of AL-CTAB particles were modified by changing the AL concentration and the dispersion agent. AL (0.3 M) dissolved in tetrahydrofuran could form a uniform size (300 nm) of particles with a regular spherical structure. Subsequently, ABA was loaded on the prepared nanomicroparticles to synthesize the capsule formulation of ABA@AL-CTAB. The controlled-release behavior and the antiphotolysis performance as well as the thermal stability of ABA@AL-CTAB were proved to be superior. Lasting inhibition of Arabidopsis and rice seed germination by ABA@AL-CTAB under light irradiations implied protection of ABA from photolysis. In addition, ABA@AL-CTAB could effectively regulate plant stomata, thereby increasing plant drought resistance. Overall, lignin is suitable for the preparation of agrochemical formulations with excellent controlled release and antiphotolysis performances.


Assuntos
Ácido Abscísico/química , Preparações de Ação Retardada/química , Lignina/química , Reguladores de Crescimento de Plantas/química , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Preparações de Ação Retardada/farmacologia , Composição de Medicamentos , Germinação/efeitos dos fármacos , Germinação/efeitos da radiação , Nanopartículas/química , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Oryza/efeitos da radiação , Fotólise , Reguladores de Crescimento de Plantas/farmacologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação
17.
Anal Bioanal Chem ; 393(4): 1297-303, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19066864

RESUMO

Artemisinin is an endoperoxide sesquiterpene lactone isolated from the Chinese medicinal plant Artemisia annua L. It has been widely used in South-East Asia and Africa as an effective drug against sensitive and multidrug-resistant Plasmodium falciparum malaria. A monoclonal antibody (mAb), designated as 3H2, was generated with artesunate-bovine serum albumin conjugate as the immunogen. mAb 3H2 was used to develop a highly sensitive and specific indirect competitive enzyme-linked immunosorbent assay (icELISA) for artemisinin. The concentration of analyte producing 50% of inhibition (IC(50)) and the working range of the icELISA were 1.3 and 0.2-5.8 ng/mL, respectively. The mAb 3H2 recognized the artemisinin analogs artesunate, dihydroartemisinin, and artemether with cross-reactivity of 650%, 57%, and 3%, respectively, but negligibly recognized deoxyartemisinin and the artemisinin precursors arteannuin B and artemisinic acid. The average recoveries of artemisinin fortified in A. annua samples at concentrations from 156 to 5,000 microg/g determined by icELISA ranged from 91% to 98%. The icELISA was applied for the determination of artemisinin in different wild A. annua samples and the results were confirmed by high-performance liquid chromatography (HPLC) analysis. The correlation coefficient (R(2)) between the two assays was larger than 0.99, demonstrating a good agreement between the icELISA and HPLC results. This ELISA is suitable for quality assurance of A. annua L. materials.


Assuntos
Anticorpos Monoclonais/imunologia , Artemisia/química , Artemisininas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Cromatografia Líquida de Alta Pressão , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/normas , Soros Imunes , Sensibilidade e Especificidade
18.
RSC Adv ; 9(12): 6548-6555, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35518461

RESUMO

Methods for enhancing enzyme activities in two-phase systems are getting more attention. Phospholipase D (PLD) was successfully encapsulated into metal-surfactant nanocapsules (MSNCs) using a one-pot self-assembly technique in an aqueous solution. The highest yield for the production of high-value phosphatidylserine (PS) from low-value phosphatidylcholine (PC) in the two-phase system was achieved by encapsulating PLD into MSNCs formed from Ca2+ which gave an enzyme activity that was 133.6% of that of free PLD. The PLD@MSNC transformed the two-phase system into an emulsion phase system and improved the organic solvent tolerance, pH and thermal stabilities as well as the storage stability and reusability of the enzyme. Under optimal conditions, PLD@MSNC generated 91.9% PS over 8 h in the two-phase system, while free PLD generated only 77.5%.

19.
J Biotechnol ; 292: 39-49, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30690095

RESUMO

Metal-driven papain-surfactant nanocomposite (PA@MSNC), a novel soft nanobiocatalyst, was successfully prepared via one-pot self-assembly technique in aqueous solution for the biosynthesis of N-(benzyloxycarbonyl)-L-alanyl-L-glutamine (Z-Ala-Gln) dipeptide in deep eutectic solvents (DESs). The metal-driven self-assembly process generated PA@MSNC as nanospheres of ˜130 nm in diameter, with high protein loading and relative enzyme activity of 420 mg/g and 80% (4270 U/g protein), respectively. PA@MSNC showed high apparent substrate affinity and catalytic efficiency. The stability of PA@MSNC at high temperature and extreme pH was significantly higher than that of free PA. Catalysis efficiency for the biosynthesis of Z-Ala-Gln by PA@MSNC in choline chloride: glycerol reaction medium was 1.69-fold higher than that of free PA, achieving a high product yield of 75.7% within 4 h. PA@MSNC also showed better techno-economic performance. We propose that enzyme-surfactant nanocomposite via metal-driven dynamically reversible coordination interactions contribute simultaneously promotes catalytic flexibility and configurational stability. The generated PA@MSNC has potential practical implications for green synthesis of dipeptide in DESs.


Assuntos
Ácido Desoxicólico/química , Dipeptídeos/química , Manganês/química , Nanocompostos/química , Papaína/química , Tensoativos/química , Biocatálise , Colina/química , Glicerol/química , Concentração de Íons de Hidrogênio , Solventes/química , Temperatura
20.
IET Nanobiotechnol ; 13(7): 712-719, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31573540

RESUMO

This report investigates the spraying of nano-silica and fullerene on cucumber leaves to expose their ability to reduce the toxicity and uptake of metal(loid)s. Cucumber seedlings were randomly divided into six treatment groups: 10 mg/L nano-SiO2, 20 mg/L nano-SiO2, 10 mg/L Fullerene, 20 mg/L Fullerene, 5 mg/L Fullerene + 5 mg/L nano-SiO2, and 10 mg/L Fullerene + 10 mg/L nano-SiO2. Nano-silica-treated plants exhibited evidence of the potential mitigation of metal(loid)s poisoning. Specifically, results showed that 20 mg/L of nano-silica promoted Cd uptake by plants; comparatively, 10 mg/L of nano-silica did not significantly increase the silicon content in plants. Both low-concentration combined treatment and low-concentration fullerene groups inhibited metal(loid)s uptake by plants. Scanning electron microscopy (SEM) was then used to observe the surface morphology of cucumber leaves. Significant differences were observed on disease resistance in plants across the different nano-material conditions. Collectively, these findings suggest that both nano-silica materials and fullerene have the potential to control metal(loid)s toxicity in plants.


Assuntos
Absorção Fisiológica/efeitos dos fármacos , Aerossóis/farmacologia , Cucumis sativus/metabolismo , Metais Pesados/farmacocinética , Nanoestruturas , Poluentes do Solo/farmacocinética , Arsênio/farmacocinética , Arsênio/toxicidade , Biodegradação Ambiental , Cádmio/farmacocinética , Cádmio/toxicidade , Cucumis sativus/efeitos dos fármacos , Cucumis sativus/crescimento & desenvolvimento , Teste de Materiais , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Desenvolvimento Vegetal/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Solo/química , Poluentes do Solo/toxicidade
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