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1.
Genome ; 65(8): 443-457, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35849843

RESUMO

Aquilaria sinensis is an important non-timber tree species for producing high-value agarwood, which is widely used as a traditional medicine and incense. Agarwood is the product of Aquilaria trees in response to injury and fungal infection. The APETALA2/ethylene responsive factor (AP2/ERF) transcription factors (TFs) play important roles in plant stress responses and metabolite biosynthesis. In this study, 119 AsAP2/ERF genes were identified from the A. sinensis genome and divided into ERF, AP2, RAV, and Soloist subfamilies. Their conserved motif, gene structure, chromosomal localization, and subcellular localization were characterized. A stress/defense-related ERF-associated amphiphilic repression (EAR) motif and an EDLL motif were identified. Moreover, 11 genes that were highly expressed in the agarwood layer in response to whole-tree agarwood induction technique (Agar-Wit) treatment were chosen, and their expression levels in response to methyl jasmonate (MeJA), salicylic acid (SA), or salt treatment were further analyzed using the quantitative real time PCR (qRT-PCR). Among the 11 genes, eight belonged to subgroup B-3. All 11 genes were significantly upregulated under salt treatment, while eight genes were significantly induced by both MeJA and SA. In addition, the gene clusters containing these upregulated genes on chromosomes were observed. The results obtained from this research not only provide useful information for understanding the functions of AP2/ERF genes in A. sinensis but also identify candidate genes and gene clusters to dissect their regulatory roles in agarwood formation for future research.


Assuntos
Regulação da Expressão Gênica de Plantas , Thymelaeaceae , Etilenos , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Thymelaeaceae/genética , Thymelaeaceae/metabolismo
2.
Bioorg Med Chem Lett ; 43: 127898, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33684440

RESUMO

A series of target compounds 1,3-benzodioxole-based fibrate derivatives were designed and synthesized. All the target compounds were preliminarily evaluated by hyperlipidemia mice induced by Triton WR-1339, in which compound 12 displayed a greater anti-hyperlipidemia activity than other compounds as well as positive drug fenofibrate (FF). 12 showed a significant reduction of plasma lipids, such as triglycerides (TG), total cholesterol (TC) and low-density lipoprotein cholesterin (LDL-C), in high fat diet (HFD) induced hyperlipidemic mice. In addition, hepatic transaminases (AST and ALT) were ameliorated after administration of 12, in particular the AST, and the histopathological examination showed that 12 improved the hepatic lipid accumulation. The expression of PPAR-α involved in lipids metabolism was up-regulated in the liver tissues of 12-treated group. Other significant activity such as antioxidant, and anti-inflammation was confirmed and reinforced the effects of 12 as a potential hypolipidemia and hepatoprotective agent.


Assuntos
Dioxóis/farmacologia , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/farmacologia , Lipídeos/antagonistas & inibidores , Substâncias Protetoras/farmacologia , Animais , Dieta Hiperlipídica/efeitos adversos , Dioxóis/síntese química , Dioxóis/química , Relação Dose-Resposta a Droga , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/metabolismo , Hipolipemiantes/síntese química , Hipolipemiantes/química , Camundongos , Estrutura Molecular , Substâncias Protetoras/síntese química , Substâncias Protetoras/química , Relação Estrutura-Atividade
3.
J Exp Bot ; 71(3): 1128-1138, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31639819

RESUMO

Agarwood is derived from wounds in Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury; However, the molecular mechanisms by which wounding leads to sesquiterpene formation remain largely unknown. Agarwood sesquiterpene synthase 1 (ASS1) is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a crucial jasmonate (JA)-responsive wound-inducible synthase. However, it is not known why ASS1 is not expressed in healthy trees and how its expression is induced as a result of wounding. Here, we report that ASS1 is a wound-induced gene with a promoter in which a 242-bp region (-973 to -731bp) is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Down-regulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. In addition, AsWRKY44 is degraded and the expression of ASS1 is significantly up-regulated in response to exogenous application of methyl jasmonate. Thus, AsWRKY44 is a crucial negative regulator of wound-induced ASS1 transcription, and is central to the mechanism of sesquiterpene biosynthesis in agarwood.


Assuntos
Sesquiterpenos/metabolismo , Thymelaeaceae/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Regiões Promotoras Genéticas , Thymelaeaceae/genética
4.
Chin Med Sci J ; 35(2): 142-150, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32684234

RESUMO

Objective The purpose of this study was to produce an arginylglycylaspartic acid (RGD) peptide-modified ultra-small superparamagnetic iron oxide (Fe3O4) nanoparticles (NPs) for targeted magnetic resonance (MR) imaging of hepatocellular carcinoma (HCC) cells and verify its utility as a T1 positive MRI imaging contrast agent in vitroand in vivo.Methods The carboxylated Fe3O4 NPs stabilized with sodium citrate were conjugated with polyethylene glycol (PEG)-linked RGD nanoparticles to form a novel target contrast agent Fe3O4-PEG-RGD NPs. The specificity of Fe3O4-PEG-RGD to bind RGD receptor was investigated in vitro by HepG2 cellular uptake and cell MR imaging, and in vivo by MR imaging of subcutaneous HepG2 tumors of nude mice.Results The formed Fe3O4-PEG-RGD NPs displayed good biocompatibility, and the ultrahigh r1 relaxivity was 1.37 mM -1S -1. The synthesized Fe3O4-PEG-RGD NPs were demonstrated spherical-like with an approximate diameter of 2.7 nm in similar size. The targeting effect to HepG2 cells was confirmed by in vitro cellular uptake and cell MR imaging. The in vivo MR imaging of nude mice demonstrated that the MR signal intensity enhancement of HepG2 tumor in Fe3O4-PEG-RGD NPs treated mice was significantly higher than in mice treated with non-targeted Fe3O4-mPEG NPs at the same post-administration time point. Conclusion The results indicate that the Fe3O4-PEG-RGD particles have potential utility as T1 positive contrast agent in targeted MR imaging.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste/química , Neoplasias Hepáticas/diagnóstico por imagem , Nanopartículas Magnéticas de Óxido de Ferro/química , Imageamento por Ressonância Magnética/métodos , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Nus , Nanopartículas/química , Oligopeptídeos/química
5.
Bioorg Med Chem Lett ; 28(23-24): 3787-3792, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30337230

RESUMO

Hypolipidemic effects of the newly synthesized 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione-based fibrates were evaluated in Triton WR-1339 and high-fat diet (HFD)-induced hyperlipidemic mice. Preliminary screening of all the synthesized compounds was done by using an acute model (Triton WR-1339 model), in which compound 6 shown more significant antidyslipidemic activity than fenofibrate (FF). The compound 6 was also found to reduce serum triglyceride (TG), total cholesterol (TC) and low density lipoprotein cholesterin (LDL) in HFD-induced hyperlipidemic mice. Moreover, compound 6 displayed hepatoprotective effect, a significant amelioration in hepatic indices (AST and ALT) toxicity was observed and the histological examination showed that compound 6 inhibited the development of hepatic lipid accumulation and ameliorated the damage in hepatic tissue compared to model mice. Additional effects such as the potent antioxidant and anti-inflammatory action confirmed and reinforced the efficacy of compound 6 as a new agent of dual-effect hypolipidemic and hepatoprotective activities.


Assuntos
Ácidos Fíbricos/química , Ácidos Fíbricos/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/química , Hipolipemiantes/uso terapêutico , Tionas/química , Tionas/uso terapêutico , Tiofenos/química , Tiofenos/uso terapêutico , Animais , Dieta Hiperlipídica/efeitos adversos , Ácidos Fíbricos/farmacologia , Hiperlipidemias/sangue , Hiperlipidemias/etiologia , Hiperlipidemias/metabolismo , Hipolipemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Tionas/farmacologia , Tiofenos/farmacologia
6.
Bioorg Med Chem Lett ; 28(18): 3119-3122, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30119959

RESUMO

Oxidative stress has been regarded as the leading mechanism of the hepatotoxicity of clofibrate (CF). To achieve multifunctional novel hypolipidemic agents with hypolipidemia, antioxidant, and ameliorating liver injury, clofibric acid derivative hydroxytyrosol-clofibrate (CF-HT) was synthesized by molecular hybridization. CF-HT exhibited significant hypolipidemia, reducing serum triglyceride (TG), total cholesterol (TC), and malonaldehyde (MDA) by 30%, 33%, and 29% in hyperlipidemic mice induced by Triton WR 1339. CF-HT also shown hepatoprotective effect, a significant decrease in hepatic indices toxicity was observed, i.e. aspartate and lactate transaminases (AST and ALT) activities, alkalines phosphatases (ALP), and total bilirubin (TBIL) levels. The liver weight and liver coefficient were also ameliorated. Serum superoxide dismutase (SOD) was significantly elevated, and serum catalase (CAT) and malondialdehyde (MDA) content were remarkably restored. The hepatic glutathione (GSH) content was obviously increased and hepatic oxidized glutathione (GSSG) content was reduced dramatically by CF-HT, as compared to the CF treated mice (p < 0.05). Moreover, the histopathological damage that hepatocyte hyperplasia and hypertrophy was also significantly ameliorated by treatment with CF-HT. Therefore, the results indicated that CF-HT exerted more potent hypolipidemic activity and definite hepatoprotective effect which may mainly be associated with its antioxidative property in mice.


Assuntos
Antioxidantes/farmacologia , Clofibrato/farmacologia , Hepatócitos/efeitos dos fármacos , Hipolipemiantes/farmacologia , Álcool Feniletílico/análogos & derivados , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Peso Corporal/efeitos dos fármacos , Clofibrato/administração & dosagem , Clofibrato/química , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Hipolipemiantes/administração & dosagem , Hipolipemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Tamanho do Órgão/efeitos dos fármacos , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Polietilenoglicóis/farmacologia , Relação Estrutura-Atividade
7.
Plant Cell Physiol ; 58(11): 1924-1933, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29016977

RESUMO

Sesquiterpenes are one of the most important defensive secondary metabolite components of agarwood. Agarwood, which is a product of the Aquilaria sinensis response to external damage, is a fragrant and resinous wood that is widely used in traditional medicines, incense and perfume. We previously reported that jasmonic acid (JA) plays an important role in promoting agarwood sesquiterpene biosynthesis and induces expression of the sesquiterpene synthase ASS1, which is a key enzyme that is responsible for the biosynthesis of agarwood sesquiterpenes in A. sinensis. However, little is known about this molecular regulation mechanism. Here, we characterized a basic helix-loop-helix transcription factor, AsMYC2, from A. sinensis as an activator of ASS1 expression. AsMYC2 is an immediate-early jasmonate-responsive gene and is co-induced with ASS1. Using a combination of yeast one-hybrid assays and chromatin immunoprecipitation analyses, we showed that AsMYC2 bound the promoter of ASS1 containing a G-box motif. AsMYC2 activated expression of ASS1 in tobacco epidermis cells and up-regulated expression of sesquiterpene synthase genes (TPS21 and TPS11) in Arabidopsis, which was also promoted by methyl jasmonate. Our results suggest that AsMYC2 participates in the regulation of agarwood sesquiterpene biosynthesis in A. sinensis by controlling the expression of ASS1 through the JA signaling pathway.


Assuntos
Proteínas de Plantas/metabolismo , Sesquiterpenos/metabolismo , Thymelaeaceae/metabolismo , Fatores de Transcrição/metabolismo , Acetatos/metabolismo , Acetatos/farmacologia , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Arabidopsis/genética , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas , Sequências Hélice-Alça-Hélice , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Thymelaeaceae/efeitos dos fármacos , Thymelaeaceae/genética , Fatores de Transcrição/genética
8.
Yao Xue Xue Bao ; 51(4): 662-7, 2016 04.
Artigo em Zh | MEDLINE | ID: mdl-29860754

RESUMO

The MYC2 transcription factor is a member of the important plant b HLH transcription factor families, and it is also the core regulatory elements in jasmonate(JA) signaling pathway. However, there is a little information about AsMYC2 gene in Aquilaria sinensis. In this study, with the total RNA isolated from A. sinensis leave as template, the full-length coding sequence (CDS) of AsMYC2 gene was amplified using RT-PCR method and subcloned into pGEX-4T-1 vector by the gene recombination technique. The recombinant vector pGEX-4T-1-AsMYC2 was verified by restriction enzyme digestion and nucleotide sequencing, and was transformed into E. coli BL21(DE3) to express the protein. A maximum expression of soluble protein was observed with induction by 0.1 mmol·L(-1) IPTG at 37 ℃ for 4 hours. The fusion protein was purified through a Sepharose-Glutathione column, and verified by SDS-PAGE and Western blotting using an anti-GST polyclonal antibody. We successfully constructed the GST-AsMYC2 plasmid, produced and purified the GST-AsMYC2 fusion protein, which would provide the basic material for polyclonal antibody preparation, interactive factors screening and gene function research. According to the tissue-specific expression pattern analysis by q RT-PCR method, the AsMYC2 gene in A. sinensis tissues is mainly expressed in roots and stems, the main agarwood formation parts, and lowest expressed in leaves. These results indicate that AsMYC2 gene likely play some roles in agarwood formation in A. sinensis.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Proteínas de Plantas/genética , Thymelaeaceae/genética , Anticorpos , Sequência de Bases , Western Blotting , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Expressão Gênica , Plasmídeos , Proteínas Recombinantes de Fusão/biossíntese
9.
Zhongguo Zhong Yao Za Zhi ; 41(2): 192-196, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-28861962

RESUMO

The full-length coding sequence (cds) of jasmonate-zim-domain protein (AsJAZ1) gene was cloned from Aquilaria sinensis, the prokaryotic vector was constructed and the recombinant proteins expression was induced to provide the basic material for interactive proteins screen and gene function research. In this study, with the total RNA isolated from A. sinensis leave as template, the full-length cds of AsJAZ1 gene was amplified using RT-PCR method and subcloned into pET-28a vector. The recombinant plasmid identified by restriction enzyme digestion and nucleotide sequencing was transformed into E. coli BL21(DE3). Inducing with 0.5 mmol•L⁻¹ IPTG at 37 ℃ for 4 hours, a fusion protein about 39 kDa was maximumly obtained. AsJAZ1 fusion protein had been expressed successfully mainly in the form of inclusion bodies and only a very small amount was secreted into the cytoplasm in the supernatant.


Assuntos
Escherichia coli/genética , Expressão Gênica , Proteínas de Plantas/genética , Thymelaeaceae/genética , Clonagem Molecular , Escherichia coli/metabolismo , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Proteínas de Plantas/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Yao Xue Xue Bao ; 49(12): 1724-9, 2014 Dec.
Artigo em Zh | MEDLINE | ID: mdl-25920204

RESUMO

A sesquiterpene synthase (AsSS4) full-length open reading frame (ORF) cDNA was cloned from wounded stems of Aquilaria sinensis by RT-PCR method. The result showed that the ORF of AsSS4 was 1,698 bp encoding 565 amino acids. Prokaryotic expression vector pET28a-AsSS4 was constructed and transformed into E. coli BL21 (DE3) pLysS. Recombinant AsSS4 protein was obtained after induction by IPTG and SDS-PAGE analysis with a MW of 64 kD. Enzymatic reactions using farnesyl pyrophosphate showed that recombinant AsSS4 protein purified by Ni-agarose gel yielded five sesquiterpene compounds, cyclohexane, 1-ethenyl-1-methyl-2, 4-bis(1-methylethenyl)-, ß-elemene, α-guaiene, α-caryophyllene and δ-guaiene. This paper reported the first cloning and functional characterization of AsSS4 gene from A. sinensis, which will establish a foundation for future studies on the molecular mechanisms of wound-induce agarwood formation in A. sinensis


Assuntos
Alquil e Aril Transferases/biossíntese , Thymelaeaceae/enzimologia , Alquil e Aril Transferases/genética , Azulenos , Clonagem Molecular , DNA Complementar , Escherichia coli , Sesquiterpenos Monocíclicos , Fases de Leitura Aberta , Fosfatos de Poli-Isoprenil , Proteínas Recombinantes/biossíntese , Sesquiterpenos/metabolismo , Sesquiterpenos de Guaiano , Thymelaeaceae/genética
11.
Yao Xue Xue Bao ; 49(8): 1194-9, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25322564

RESUMO

Aquilaria sinensis callus induced by stem tips were used to establish the suspension cell system. The results showed that the most suitable medium for callus induction and subculture is MS + 2.0 mg x L(-1) NAA + 1.0 mg x L(-1) 6-BA. After 12 times of subculture, the energetic and loose callus, which were appropriate for cell suspension culture, were cultured and shook in liquid medium MS + 2.0 mg x L(-1) NAA + 1.0 mg x L(-1) 6-BA + 500.0 mg x L(-1) casein hydrolysate (CH) to establish the suspension cell system. The growth curve of suspension cells showed a "S" type. At the beginning of the culture, cell density increased slowly; during 4 to 6 days, suspension cells reached logarithmic growth period; during 7 to 12 days, suspension cells were in the platform period; but after 12 days, cell density and activity went down obviously. Agarwood sesquiterpenes were not detected in the suspension cells during the growth period, however, they could be detected in MeJA treated suspension cells. In this study, a stable and active growing suspension cell system was established, which was a proper system to study the mechanism of agarwood sesquiterpene formation, and additionally provided a potential way to generate agarwood sesquiterpenes through application of cell culture.


Assuntos
Técnicas de Cultura de Células , Células Vegetais/metabolismo , Thymelaeaceae/crescimento & desenvolvimento , Caules de Planta/citologia , Sesquiterpenos/metabolismo , Thymelaeaceae/citologia
12.
Zhongguo Zhong Yao Za Zhi ; 39(10): 1767-71, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-25282879

RESUMO

The study aimed to clone the open reading frame of cinnamate 4-hydroxylase (C4H) from Aquilaria sinensis and analyze the bioinformatics and expression of the gene. One unique sequence containing C4H domain was discovered in our previous reported wound transcriptome dataset of A. sinensis. The open reading frame of C4H was cloned by RT-PCR strategy with the template of mixed RNA extracted from A. sinensis stem which treated by different wound time. The bioinformatic analysis of this gene and its corresponding protein was performed. C4H expression profiles in responds to MeJA (methyl jasmonate) application were analyzed by real-time PCR. The length of C4H open reading frame (ORF) was 1 515 bp, encoding 514 amino acids. The GenBank accession number is KF134783. Inducible-experiments showed that the genes were induced by mechanical wound as well as MeJA induction, and reached the highest expression level at 8 h and 20 h, respectively. The full-length cDNA of C4H and its expression patterns will provide a foundation for further research on its function in the molecular mechanisms of aromatic compounds and flavonoids biosynthesis.


Assuntos
Clonagem Molecular , Oxirredutases/genética , Proteínas de Plantas/genética , Thymelaeaceae/enzimologia , Transcinamato 4-Mono-Oxigenase/genética , Sequência de Aminoácidos , Modelos Moleculares , Dados de Sequência Molecular , Fases de Leitura Aberta , Oxirredutases/química , Oxirredutases/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Thymelaeaceae/química , Thymelaeaceae/genética , Transcinamato 4-Mono-Oxigenase/química , Transcinamato 4-Mono-Oxigenase/metabolismo
13.
Zhongguo Zhong Yao Za Zhi ; 39(6): 972-80, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24956835

RESUMO

OBJECTIVE: This study aimed to clone the acetyl-CoA C-acetyl transferase (AACT) gene from Aquilaria sinensis and analyze the bioinformatics and expression of the gene. METHOD: One unique sequence containing partly AACT gene sequence was discovered in our previous transcriptome dataset of A. sinensis. AACT gene was cloned by RT-PCR and RACE strategy with the template of RNA extracted from A. sinensis stem. The bioinformatic analysis of this gene and its corresponding protein was performed. The AsAACT expression in calli was analyzed with GADPH gene as an internal control gene in wounded condition by qRT-PCR technique. RESULT: One unique sequence of AACT, named as AsAACT, was cloned from A. sinensis. The full length of AsAACT cDNA was containing a 1 236 bp ORF that encoded 411 amino acids. The result of qRT-PCR displayed that the highest expression level was at 4 h. which indicated that it was possibly involved in early-stage response to wound. CONCLUSION: Cloning and analyzing AsAACT gene from A. sinensis provided basic information for study the function and expression regulation of AsAACT in terpenoid biosynthesis.


Assuntos
Acetil-CoA C-Acetiltransferase/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Regulação da Expressão Gênica de Plantas , Thymelaeaceae/enzimologia , Thymelaeaceae/genética , Acetil-CoA C-Acetiltransferase/química , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína
14.
Zhongguo Zhong Yao Za Zhi ; 39(2): 192-6, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24761630

RESUMO

To investigate the mechanism of agarwood formation in Aquilaria sinensis induced by Lasiodiplodia theobromae, the fermentation liquor of L. theobromae was analyzed qualitatively and quantitatively by gas chromatography-mass spectrometry (GC-MS). JAs were detected in the fermentation liquor. The effect of the fermentation liquor on the abundance of sesquiterpenes in the callus of A. sinensis was analyzed by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). And the fermentation liquor stimulated alpha-guaiene, alpha-humulene and delta-guaiene biosynthesis in calli. It was inferred that L. theobromae produced JAs, which resulted in a significant increase of sesquiterpenes in A. sinensis.


Assuntos
Ascomicetos/fisiologia , Fermentação , Sesquiterpenos/metabolismo , Thymelaeaceae/metabolismo , Thymelaeaceae/microbiologia
15.
Macromolecules ; 57(12): 5561-5577, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38948183

RESUMO

Traditional π-conjugated luminescent macromolecules typically suffer from aggregation-caused quenching (ACQ) and high cytotoxicity, and they require complex synthetic processes. In contrast, nonconventional luminescent macromolecules (NCLMs) with nonconjugated structures possess excellent biocompatibility, ease of preparation, unique luminescence behavior, and emerging applications in optoelectronics, biology, and medicine. NCLMs are currently believed to produce inherent luminescence due to through-space conjugation of overlapping electron orbitals in solid/aggregate states. However, as experimental facts continue to exceed expectations or even overturn some previous assumptions, there is still controversy about the detailed luminous mechanism of NCLMs, and extensive studies are needed to further explore the mechanism. This Perspective highlights recent progress in NCLMs and classifies and summarizes these advances from the viewpoint of molecular design, mechanism exploration, applications, and challenges and prospects. The aim is to provide guidance and inspiration for the huge fundamental and practical potential of NCLMs.

16.
ACS Macro Lett ; 13(1): 52-57, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38147539

RESUMO

The development of single-component materials with low cytotoxicity and multichannel fluorescence imaging capability is a research hotspot. In the present work, highly electron-deficient pyrazine monomers were covalently connected into a polyurethane backbone using addition polymerization with terminal poly(ethylene glycol) monomethyl ether units containing a high density of electron pairs. Thereby, an amphiphilic polyurethane-pyrazine (PUP) derivative has been synthesized. The polymer displays cluster-induced emission through compact inter- and/or intramolecular noncovalent interactions and extensive through-space electron coupling and delocalization. Molecular rigidity facilitates red-shifted emission. Based on hydrophilic/hydrophobic interactions and excitation dependence emission at low concentrations, PUP has been self-assembled into fluorescent nanoparticles (PUP NPs) without additional surfactant. PUP NPs have been used for cellular multicolor imaging to provide a variety of switchable colors on demand. This work provides a simple molecular design for environmentally sustainable, luminescent materials with excellent photophysical properties, biocompatibility, low cytotoxicity, and color modulation.


Assuntos
Polietilenoglicóis , Poliuretanos , Polietilenoglicóis/química , Polímeros/química , Pirazinas
17.
J Exp Bot ; 64(18): 5443-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24078667

RESUMO

The light-harvesting chlorophyll a/b-binding (LHCB) proteins are the apoproteins of the light-harvesting complex of photosystem II. In the present study, we observed that downregulation of any of the six LHCB genes resulted in abscisic acid (ABA)-insensitive phenotypes in seed germination and post-germination growth, demonstrating that LHCB proteins are positively involved in these developmental processes in response to ABA. ABA was required for full expression of different LHCB members and physiologically high levels of ABA enhanced LHCB expression. The LHCB members were shown to be targets of an ABA-responsive WRKY-domain transcription factor, WRKY40, which represses LHCB expression to balance the positive function of the LHCBs in ABA signalling. These findings revealed that ABA is an inducer that fine-tunes LHCB expression at least partly through repressing the WRKY40 transcription repressor in stressful conditions in co-operation with light, which allows plants to adapt to environmental challenges.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação à Clorofila/metabolismo , Fatores de Transcrição/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Ligação à Clorofila/genética , Regulação da Expressão Gênica de Plantas , Germinação , Complexos de Proteínas Captadores de Luz/genética , Complexos de Proteínas Captadores de Luz/metabolismo , Liases/genética , Liases/metabolismo , Mutação , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Regiões Promotoras Genéticas , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética
18.
Yao Xue Xue Bao ; 48(6): 953-9, 2013 Jun.
Artigo em Zh | MEDLINE | ID: mdl-23984534

RESUMO

3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) is the first rate-limiting enzyme for sesquiterpene synthesis in the mevalonate (MVA) pathway. The specific primers were designed according to the transcript sequence of AsHMGR2 from the Aquilaria sinensis (Lour.) Gilg transcriptome database. The full-length cDNA of AsHMGR2 was cloned by RT-PCR and rapid amplification of cDNA ends (RACE) technology, and was analyzed at bioinformatics levels; AsHMGR2 expression profiles in different tissues and in responds to different treatments were analyzed by real-time PCR. The length of AsHMGR2 Open Reading Frame (ORF) was 1 749 bp, encoding 582 amino acids. The GenBank accession number is KC140287. Tissue expression analysis indicated that AsHMGR2 was mainly expressed in root and shoot tips, followed by stem, and was lowest in leaves. Inducible-experiments showed that the genes were induced by mechanical wound as well as chemical liquid induction, and reached the highest expression level at 6 h and 8 h, separately. The full-length cDNA of AsHMGR2 and its expression patterns will provide a foundation for further research on its function in agarwood sesquiterpene biosynthesis.


Assuntos
Hidroximetilglutaril-CoA Redutases/genética , Fases de Leitura Aberta , Thymelaeaceae/enzimologia , Sequência de Aminoácidos , Clonagem Molecular , DNA Complementar/genética , Amplificação de Genes , Hidroximetilglutaril-CoA Redutases/isolamento & purificação , Isoenzimas/genética , Isoenzimas/isolamento & purificação , Filogenia , Folhas de Planta/enzimologia , Raízes de Plantas/enzimologia , Brotos de Planta/enzimologia , Caules de Planta/enzimologia , Plantas Medicinais/enzimologia , Reação em Cadeia da Polimerase em Tempo Real
19.
Yao Xue Xue Bao ; 48(8): 1345-52, 2013 Aug.
Artigo em Zh | MEDLINE | ID: mdl-24187847

RESUMO

The ORF sequence of glycosyltransferase gene BcUGT1 cloned from Bupleurum chinense DC. was analyzed and its three dimentional structure was predicted. Using qRT-PCR method, the expression characteristics of BcUGT1 after methyl jasmonate (MeJA) induction and in different plant tissues were investigated. The results showed that BcUGT1 may be involved in saikosaponin biosynthesis in B. chinense. Thereafter, the recombinant vectors of BcUGT1 were constructed for its expression in E. coli. The target protein was successfully expressed and purified. In the present study, three vectors, pRSET-A, pET-28a (+) and pET-30a (+), and three isolates of E. coli, BL21 (DE3) plysS, BL21A1 and BL21-CodonPlus (DE3)-RIPL were used under different induction conditions, such as different concentrations and during times of inducers (L-arabinose and IPTG) and different inducing temperatures. The results showed that in the condition of 0.5 or 1 mmol x L(-1) IPTG, 16 degrees C, 20 h, target protein expressed in BL21-CodonPlus (DE3)-RIPL with pET-28a (+) or pET-30a (+) as vector. Using PrepEase His-tagged protein purification kit, the target protein was purified. The present work will be helpful for follow-up bio-function analysis of BcUGT1.


Assuntos
Bupleurum/química , Escherichia coli/genética , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Ácido Oleanólico/análogos & derivados , Saponinas/biossíntese , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA de Plantas/genética , Escherichia coli/metabolismo , Vetores Genéticos , Glicosiltransferases/isolamento & purificação , Ácido Oleanólico/biossíntese , Fases de Leitura Aberta/genética , Filogenia , Plantas Medicinais/química , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
20.
Hell J Nucl Med ; 16(3): 199-203, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24251307

RESUMO

Mediastinal lymph node metastases (MLNM) from differentiated thyroid carcinoma (DTC) are considered difficult to diagnose. The aim of this study was to assess the value of iodine-131 (131I) single photon emission tomography/computed tomography (SPET/CT) and of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for the diagnosis of MLNM from DTC. Five hundred and eleven consecutive patients operated for DTC and treated with 131I for ablation of the remnant thyroid and/or for treatment of metastases were enrolled in the study and underwent an 131I whole body scan (131I-WBS). Thirty seven sites of increased 131I uptake, on the 131I-WBS that could be an indication for MLNM were re-evaluated by a 131I-SPET/CT scan. Thirty four other patients with negative 131I-WBS but having elevated serum thyroglobulin (Tg), were examined by 18F-FDG PET/CT to possibly diagnose MLNM. A total of 44 DTC patients with MLNM were identified, among the above 37 and 34 cases: 25/37 (67.6%) cases were examined and identified by 131I-SPET/CT and 19/34 (55.9%) cases by 18F-FDG PET/CT. A total of 25 and 19 cases were identified. The male-to-female ratio and the average age in patients with 18F-FDG-avid MLNM were significantly higher than in patients with 131I-avid MLNM. Among the above 44 patients, 40 patients had superior mediastinal nodal metastases, 9 had aortic nodal metastases and only 1 inferior mediastinal nodal metastases. A patient could have metastases in more than one site. In conclusion, our study suggests that in 511 operated DTC patients, treated for remnant ablation and/or for metastases and examined by 131I-WBS, there were 37 cases doubtful of having MLNM in the 131I-WBS and 34 cases doubtful, because of negative 131I-WBS and elevated Tg. The 131I-SPET/CT scan was sensitive for detecting MLNM in 25 of the 37 cases and the 18F-FDG PET/CT in 19 of the 34 cases. These hybrid imaging modalities, when applied as above, were suitable for detecting more MLNM and thus, better supporting treatment planning in these DTC patients.


Assuntos
Carcinoma/diagnóstico , Carcinoma/secundário , Linfonodos/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico , Tomografia Computadorizada de Emissão/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Carcinoma/epidemiologia , Carcinoma/radioterapia , China/epidemiologia , Feminino , Fluordesoxiglucose F18 , Humanos , Radioisótopos do Iodo/uso terapêutico , Metástase Linfática , Masculino , Mediastino/diagnóstico por imagem , Pessoa de Meia-Idade , Imagem Multimodal/estatística & dados numéricos , Prevalência , Compostos Radiofarmacêuticos/uso terapêutico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/radioterapia , Resultado do Tratamento
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