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1.
FASEB J ; 37(7): e23012, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37272854

RESUMO

As an end product of purine metabolism, uric acid (UA) is a major endogenous antioxidant in humans. However, impaired UA synthesis and excretion can lead to hyperuricemia (HUA), which may in turn induce endothelial dysfunction (ED) and contribute to the pathogenesis of cardiovascular diseases (CVDs; e.g., atherosclerosis and hypertension). In this review, we discuss recent advances and novel insights into the effects exerted by HUA conditions in ED and related underlying mechanisms focusing on impaired UA metabolism, reduction in the synthesis and bioavailability of nitric oxide, endothelial cell injury, the endothelial-to-mesenchymal transition, insulin resistance, procoagulant activity, and acquisition of an inflammatory phenotype. We additionally discuss intervention strategies for HUA-induced ED and the paradoxical roles of UA in endothelial function. We summarize major conclusions and perspectives: the deleterious effects of HUA contribute to the initiation and progression of CVD-related ED. However, the treatment strategies (in addition to urate-lowering therapy) for increasing endothelial function are limited because the majority of literature on pharmacological and pathophysiological mechanisms underlying HUA-induced ED solely describes in vitro models. Therefore, a better understanding of the mechanisms involved in HUA-induced ED is critical to the development of novel therapies for preventing and treating CVD-HUA comorbidities.


Assuntos
Doenças Cardiovasculares , Hipertensão , Hiperuricemia , Humanos , Hiperuricemia/metabolismo , Doenças Cardiovasculares/etiologia , Antioxidantes/uso terapêutico , Ácido Úrico/metabolismo , Hipertensão/metabolismo
2.
Int J Mol Sci ; 25(9)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38732182

RESUMO

Anthocyanins are water-soluble flavonoid pigments that play a crucial role in plant growth and metabolism. They serve as attractants for animals by providing plants with red, blue, and purple pigments, facilitating pollination and seed dispersal. The fruits of solanaceous plants, tomato (Solanum lycopersicum) and eggplant (Solanum melongena), primarily accumulate anthocyanins in the fruit peels, while the ripe fruits of Atropa belladonna (Ab) have a dark purple flesh due to anthocyanin accumulation. In this study, an R2R3-MYB transcription factor (TF), AbMYB1, was identified through association analysis of gene expression and anthocyanin accumulation in different tissues of A. belladonna. Its role in regulating anthocyanin biosynthesis was investigated through gene overexpression and RNA interference (RNAi). Overexpression of AbMYB1 significantly enhanced the expression of anthocyanin biosynthesis genes, such as AbF3H, AbF3'5'H, AbDFR, AbANS, and Ab3GT, leading to increased anthocyanin production. Conversely, RNAi-mediated suppression of AbMYB1 resulted in decreased expression of most anthocyanin biosynthesis genes, as well as reduced anthocyanin contents in A. belladonna. Overall, AbMYB1 was identified as a fruit-expressed R2R3-MYB TF that positively regulated anthocyanin biosynthesis in A. belladonna. This study provides valuable insights into the regulation of anthocyanin biosynthesis in Solanaceae plants, laying the foundation for understanding anthocyanin accumulation especially in the whole fruits of solanaceous plants.


Assuntos
Antocianinas , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fatores de Transcrição , Antocianinas/biossíntese , Antocianinas/metabolismo , Frutas/metabolismo , Frutas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/genética , Interferência de RNA
3.
BMC Genomics ; 23(1): 577, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35953771

RESUMO

BACKGROUND: As a valuable medicinal plant, Rhodiola has a very long history of folk medicine used as an important adaptogen, tonic, and hemostatic. However, our knowledge of the chloroplast genome level of Rhodiola is limited. This drawback has limited studies on the identification, evolution, genetic diversity and other relevant studies on Rhodiola. RESULTS: Six Rhodiola complete chloroplast genomes were determined and compared to another Rhodiola cp genome at the genome scale. The results revealed a cp genome with a typical quadripartite and circular structure that ranged in size from 150,771 to 151,891 base pairs. High similarity of genome organization, gene number, gene order, and GC content were found among the chloroplast genomes of Rhodiola. 186 (R. wallichiana) to 200 (R. gelida) SSRs and 144 pairs of repeats were detected in the 6 Rhodiola cp genomes. Thirteen mutational hotspots for genome divergence were determined and could be used as candidate markers for phylogenetic analyses and Rhodiola species identification. The phylogenetic relationships inferred by members of Rhodiola cluster into two clades: dioecious and hermaphrodite. Our findings are helpful for understanding Rhodiola's taxonomic, phylogenetic, and evolutionary relationships. CONCLUSIONS: Comparative analysis of chloroplast genomes of Rhodiola facilitates medicinal resource conservation, phylogenetic reconstruction and biogeographical research of Rhodiola.


Assuntos
Genoma de Cloroplastos , Rhodiola , Composição de Bases , Marcadores Genéticos , Filogenia , Rhodiola/genética
4.
Metab Eng ; 72: 237-246, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35390492

RESUMO

Atropa belladonna is an important industrial crop for producing anticholinergic tropane alkaloids (TAs). Using glyphosate as selection pressure, transgenic homozygous plants of A. belladonna are generated, in which a novel calmodulin gene (AbCaM1) and a reported EPSPS gene (G2-EPSPS) are co-overexpressed. AbCaM1 is highly expressed in secondary roots of A. belladonna and has calcium-binding activity. Three transgenic homozygous lines were generated and their glyphosate tolerance and TAs' production were evaluated in the field. Transgenic homozygous lines produced TAs at much higher levels than wild-type plants. In the leaves of T2GC02, T2GC05, and T2GC06, the hyoscyamine content was 8.95-, 10.61-, and 9.96 mg/g DW, the scopolamine content was 1.34-, 1.50- and 0.86 mg/g DW, respectively. Wild-type plants of A. belladonna produced hyoscyamine and scopolamine respectively at the levels of 2.45 mg/g DW and 0.30 mg/g DW in leaves. Gene expression analysis indicated that AbCaM1 significantly up-regulated seven key TA biosynthesis genes. Transgenic homozygous lines could tolerate a commercial recommended dose of glyphosate in the field. In summary, new varieties of A. belladonna not only produce pharmaceutical TAs at high levels but tolerate glyphosate, facilitating industrial production of TAs and weed management at a much lower cost.


Assuntos
Atropa belladonna , Hiosciamina , Atropa belladonna/genética , Atropa belladonna/metabolismo , Regulação da Expressão Gênica de Plantas , Glicina/análogos & derivados , Hiosciamina/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Escopolamina/metabolismo , Tropanos/metabolismo , Glifosato
5.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2514-2518, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047098

RESUMO

This paper aims to investigate the chemical constituents of the seeds of Herpetospermum pedunculosum. One new coumarin and two known lignans were isolated from the ethanolic extract of the seeds of H. pedunculosum with thin layer chromatography(TLC), silica gel column chromatography, Sephedax LH-20 chromatography, Semi-preparative high performance liquid chromatography and recrystallization, etc. Their structures were elucidated as herpetolide H(1), phyllanglaucin B(2), and buddlenol E(3) by analysis of their physicochemical properties and spectral data. Among them, compound 1 was a new compound, and compounds 2 and 3 were isolated from this genus for the first time. In vitro anti-inflammatory activity test showed that herpetolide H had certain NO inhibitory activity for LPS-induced RAW 264.7 cells, with its IC_(50) value of(46.57±3.28) µmol·L~(-1).


Assuntos
Cucurbitaceae , Lignanas , Cromatografia Líquida de Alta Pressão , Cumarínicos/farmacologia , Sementes
6.
New Phytol ; 225(5): 1906-1914, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31705812

RESUMO

Some medicinal plants of the Solanaceae produce pharmaceutical tropane alkaloids (TAs), such as hyoscyamine and scopolamine. Littorine is a key biosynthetic intermediate in the hyoscyamine and scopolamine biosynthetic pathways. However, the mechanism underlying littorine formation from the precursors phenyllactate and tropine is not completely understood. Here, we report the elucidation of littorine biosynthesis through a functional genomics approach and functional identification of two novel biosynthesis genes that encode phenyllactate UDP-glycosyltransferase (UGT1) and littorine synthase (LS). UGT1 and LS are highly and specifically expressed in Atropa belladonna secondary roots. Suppression of either UGT1 or LS disrupted the biosynthesis of littorine and its TA derivatives (hyoscyamine and scopolamine). Purified His-tagged UGT1 catalysed phenyllactate glycosylation to form phenyllactylglucose. UGT1 and LS co-expression in tobacco leaves led to littorine synthesis if tropine and phenyllactate were added. This identification of UGT1 and LS provides the missing link in littorine biosynthesis. The results pave the way for producing hyoscyamine and scopolamine for medical use by metabolic engineering or synthetic biology.


Assuntos
Derivados da Atropina , Solanaceae , Genômica , Escopolamina , Tropanos
7.
Arch Microbiol ; 202(7): 1717-1728, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32313992

RESUMO

Paeonia ludlowii is indigenous to Tibet and has an important ecological and economic value in China. In Tibet, P. ludlowii has been used in folk medicine with relative success. Plant microbial endophytes play an important role in plant growth, health and ecological function. The diversity of endophytic bacteria associated with P. ludlowii remains poorly understood. In this study, the structure of the endophytic bacterial communities associated with different tissues, including fruits, flowers, leaves, stems, and roots, and rhizosphere soils was analyzed with Illumina MiSeq sequencing of bacterial 16S rDNA. A total of 426,240 sequences and 4847 operational taxonomic units (OTUs) were obtained. The OTUs abundance of roots was higher than that of other tissues; however, the OTUs abundance was similar among different deep soil samples. In the plant tissues, Cyanobacteria was the most abundant bacterial phylum, followed by Proteobacteria; however, the most abundant phyla were Proteobacteria and Acidobacteria in soil samples from three different layers. In addition, the diversity and richness of the microorganisms in the soil were very similar to those in roots but higher than those in other tissues of P. ludlowii. Predictive metagenome analysis revealed that endophytic bacteria play critical functional roles in P. ludlowii. This conclusion could facilitate the study of the ecological functions of endophytic bacteria and their interactions with P. ludlowii to analyze the reasons why this important medicinal plant is becoming endangered.


Assuntos
Biodiversidade , Espécies em Perigo de Extinção , Endófitos/classificação , Endófitos/fisiologia , Paeonia/microbiologia , Rizosfera , Microbiologia do Solo , Cianobactérias/genética , Cianobactérias/isolamento & purificação , DNA Ribossômico/genética , Endófitos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Raízes de Plantas/microbiologia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/genética , Tibet
8.
Can J Physiol Pharmacol ; 98(6): 366-372, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32011913

RESUMO

Herpetotriol, a typical lignan in Herpetospermum pedunculosum Wall's seeds that has long been used to treat icterhepatitis and indigestion and other related diseases in Tibet, is of potential hepatoprotection. This study aims to study the pharmacokinetics features of herpetotriol, including the blood drug concentration - time curve and tissue distribution. The ultrahigh-performance liquid chromatography with tandem mass spectrometry method was established to detect herpetotriol concentration in plasma and tissues, and the method showed good linearity from 10 to 2000 ng/mL (r ≥ 0.9972) and sensitivity (≥10 ng/mL). Our blood drug concentration - time curve indicated that herpetotriol was distributed quickly in rats with a Tmax value at about 0.083 h and eliminated rapidly with a clearance rate at 98.13 ± 8.05 and 137.04 ± 9.48 L·h-1·kg-1 with doses of 5 and 2.5 mg/kg, respectively. Although herpetotriol was detectable in all tested tissues, it has a higher concentration in liver than in heart, lung, spleen, and kidney, which is in line with its hepatoprotection. The pharmacokinetics features uncovered by the present study could provide more information for future pharmacological and toxicological study of herpetotriol.


Assuntos
Cromatografia Líquida de Alta Pressão , Furanos/farmacocinética , Espectrometria de Massas em Tandem , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
9.
J Exp Bot ; 70(18): 4835-4848, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31087059

RESUMO

Basic helix-loop-helix (bHLH) proteins are the second largest family of transcription factors (TFs) involved in developmental and physiological processes in plants. In this study, 205 putative bHLH TF genes were identified in the genome of Artemisia annua and expression of 122 of these was determined from transcriptomes used to construct the genetic map of A. annua. Analysis of gene expression association allowed division of the 122 bHLH TFs into five groups. Group V, containing 15 members, was tightly associated with artemisinin biosynthesis genes. Phylogenetic analysis indicated that two bHLH TFs, AabHLH106 and AabHLH112, were clustered with Arabidopsis ICE proteins. AabHLH112 was induced by low temperature, while AabHLH106 was not. We therefore chose AabHLH112 for further examination. AabHLH112 was highly expressed in glandular secretory trichomes, flower buds, and leaves. Dual-luciferase assays demonstrated that AabHLH112 enhanced the promoter activity of artemisinin biosynthesis genes and AaERF1, an AP2/ERF TF that directly and positively regulates artemisinin biosynthesis genes. Yeast one-hybrid assays indicated that AabHLH112 could bind to the AaERF1 promoter, but not to the promoters of artemisinin biosynthesis genes. Overexpression of AabHLH112 significantly up-regulated the expression levels of AaERF1 and artemisinin biosynthesis genes and consequently promoted artemisinin production.


Assuntos
Artemisia annua/genética , Artemisininas/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Terminação de Peptídeos/genética , Proteínas de Plantas/genética , Artemisia annua/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Temperatura Baixa , Flores/metabolismo , Perfilação da Expressão Gênica , Fatores de Terminação de Peptídeos/metabolismo , Filogenia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Tricomas/metabolismo
10.
Biotechnol Appl Biochem ; 66(4): 597-606, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31051047

RESUMO

Przewalskia tangutica is a traditional medicinal plant from Tibet used for the analgesic effect from the tropane alkaloids (TAs) produced by the plant. Its roots have the highest yield of hyoscyamine in all plant species and so have been overharvested becoming an endangered medicinal plant species. Metabolic engineering is a good way to improve the yield of TAs in plants. In our study, two functionally distinct tropinone reductases genes, PtTRI and PtTRII, were cloned from P. tangutica and the functional divergence were characterized. The enzyme kinetics of PtTRI and PtTRII were investigated. The phylogenetic analysis classified them into different clades: PtTRI and PtTRII were in the clade of tropine-forming reductase and pseudotropine-forming reductase, respectively. We found PtTRI to be expressed in the roots but less in leaves, whereas PtTRII was expressed in the roots at higher levels than in the leaves. The kinetic parameters (Km , Vmax , and Kcat ) were analyzed using purified recombinant enzymes at their optimum pH. Enzymatic analysis results showed that tropinone is a better substrate for PtTRII compared with PtTRI, suggesting that PtTRII might be a potential gene target for TA biosynthesis engineering. Compared with the reported TRIs, PtTRI exhibited a higher affinity for tropinone.


Assuntos
Oxirredutases do Álcool/metabolismo , Solanaceae/enzimologia , Oxirredutases do Álcool/química , Oxirredutases do Álcool/genética , Cinética , Engenharia Metabólica
11.
Molecules ; 24(5)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823686

RESUMO

Pterocephalus hookeri was used as a traditional Chinese medicine for the treatment of rheumatoid arthritis. Sweroside was a main iridoid isolated from P. hookeri. The present study aimed to investigate the anti-inflammatory effect mechanism of sweroside. In RAW264.7 cells induced by lipopolysaccharide (LPS), the abnormal proliferation, the NO content increase, and the downregulated Sirtuin1 (SIRT1) expression were observed. Sweroside could alleviate the inflammation by inhibiting cell proliferation through arresting the cell cycle at the G0/G1 phase, by suppressing pro-inflammatory cytokines and by promoting anti-inflammatory cytokines in LPS-induced RAW264.7 cells. Further mechanism research indicated that sweroside could activate the SIRT1, then suppress the nuclear factor-kappa B (NF-κB) and promote the Forkhead transcription factor O1 (FOXO1) signaling pathways. The present study indicated that sweroside may be the main anti-inflammatory constituent of P. hookeri and a promising candidate for anti-inflammation therapy.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Proteína Forkhead Box O1/genética , Inflamação/tratamento farmacológico , Glucosídeos Iridoides/administração & dosagem , Sirtuína 1/genética , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Camundongos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/genética
12.
Zhongguo Zhong Yao Za Zhi ; 44(3): 472-474, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30989910

RESUMO

By the fourth survey of Chinese medicinal resources, new medicinal plants records of 2 genera and 5 species were reported in Tibet. They are two genera Rhynchoglossum and Asteropyrum, and five species including Rh. obliquum, A. peltatum, Urena repanda, Schefflera khasiana and Mimulus tenellus. All the voucher specimens are preserved in Herbarium of Tibet Agriculture and Animal Husbandry University.


Assuntos
Araliaceae/classificação , Lamiales/classificação , Malvaceae/classificação , Plantas Medicinais/classificação , Ranunculaceae/classificação , Tibet
13.
Biochem Biophys Res Commun ; 497(1): 25-31, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29407173

RESUMO

Scopolia lurida, a medicinal plant native to the Tibetan Plateau, is among the most effective producers of pharmaceutical tropane alkaloids (TAs). The hyoscyamine 6ß-hydroxylase genes of Hyoscyamus niger (HnH6H) and S. lurida (SlH6H) were cloned and respectively overexpressed in hairy root cultures of S. lurida, to compare their effects on promoting the production of TAs, especially the high-value scopolamine. Root cultures with SlH6H/HnH6H overexpression were confirmed by PCR and real-time quantitative PCR, suggesting that the enzymatic steps defined by H6H were strongly elevated at the transcriptional level. Tropane alkaloids, including hyoscyamine, anisodamine and scopolamine, were analyzed by HPLC. Scopolamine and anisodamine contents were remarkably elevated in the root cultures overexpressing SlH6H/HnH6H, whereas that of hyoscyamine was more or less reduced, when compared with those of the control. These results also indicated that SlH6H and HnH6H promoted anisodamine production at similar levels in S. lurida root cultures. More importantly, HnH6H-overexpressing root cultures had more scopolamine in them that did SlH6H-overexpressing root cultures. This study not only provides a feasible way of overexpressing H6H to produce high-value scopolamine in engineered root cultures of S. lurida but also found that HnH6H was better than SlH6H for engineering scopolamine production.


Assuntos
Engenharia Metabólica/métodos , Oxigenases de Função Mista/genética , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas/fisiologia , Escopolamina/metabolismo , Scopolia/fisiologia , Ativação Enzimática , Estabilidade Enzimática , Melhoramento Genético/métodos , Oxigenases de Função Mista/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Escopolamina/isolamento & purificação
14.
Mol Genet Genomics ; 293(3): 635-647, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29285563

RESUMO

Mirabilis himalaica (Edgew.) Heimerl is among the most important genuine medicinal plants in Tibet. However, the biosynthesis mechanisms of the active compounds in this species are unclear, severely limiting its application. To clarify the molecular biosynthesis mechanism of the key representative active compounds, specifically rotenoid, which is of special medicinal value for M. himalaica, RNA sequencing and TOF-MS technologies were used to construct transcriptomic and metabolomic libraries from the roots, stems, and leaves of M. himalaica plants collected from their natural habitat. As a result, each of the transcriptomic libraries from the different tissues was sequenced, generating more than 10 Gb of clean data ultimately assembled into 147,142 unigenes. In the three tissues, metabolomic analysis identified 522 candidate compounds, of which 170 metabolites involved in 114 metabolic pathways were mapped to the KEGG. Of these genes, 61 encoding enzymes were identified to function at key steps of the pathways related to rotenoid biosynthesis, where 14 intermediate metabolites were also located. An integrated analysis of metabolic and transcriptomic data revealed that most of the intermediate metabolites and enzymes related to rotenoid biosynthesis were synthesized in the roots, stems and leaves of M. himalaica, which suggested that the use of non-medicinal tissues to extract compounds was feasible. In addition, the CHS and CHI genes were found to play important roles in rotenoid biosynthesis, especially, since CHS might be an important rate-limiting enzyme. This study provides a hypothetical basis for the screening of new active metabolites and the metabolic engineering of rotenoid in M. himalaica.


Assuntos
Perfilação da Expressão Gênica/métodos , Metabolômica/métodos , Mirabilis/genética , Mirabilis/metabolismo , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Espectrometria de Massas , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Análise de Sequência de RNA
15.
J Exp Bot ; 69(5): 1109-1123, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29301032

RESUMO

The plant Artemisia annua produces the anti-malarial compound artemisinin. Although the transcriptional regulation of artemisinin biosynthesis has been extensively studied, its post-translational regulatory mechanisms, especially that of protein phosphorylation, remain unknown. Here, we report that an ABA-responsive kinase (AaAPK1), a member of the SnRK2 family, is involved in regulating artemisinin biosynthesis. The physical interaction of AaAPK1 with AabZIP1 was confirmed by multiple assays, including yeast two-hybrid, bimolecular fluorescence complementation, and pull-down. AaAPK1, mainly expressed in flower buds and leaves, could be induced by ABA, drought, and NaCl treatments. Phos-tag mobility shift assays indicated that AaAPK1 phosphorylated both itself and AabZIP1. As a result, the phosphorylated AaAPK1 significantly enhanced the transactivational activity of AabZIP1 on the artemisinin biosynthesis genes. Substituting the Ser37 with Ala37 of AabZIP1 significantly suppressed its phosphorylation, which inhibited the transactivational activity of AabZIP1. Consistent overexpression of AaAPK1 significantly increased the production of artemisinin, as well as the expression levels of the artemisinin biosynthesis genes. Our study opens a window into the regulatory network underlying artemisinin biosynthesis at the post-translational level. Importantly, and for the first time, we provide evidence for why the kinase gene AaAPK1 is a key candidate for the metabolic engineering of artemisinin biosynthesis.


Assuntos
Artemisia annua/genética , Artemisininas/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fosfotransferases/genética , Proteínas de Plantas/genética , Artemisia annua/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas , Fosforilação , Fosfotransferases/metabolismo , Filogenia , Proteínas de Plantas/metabolismo
16.
Int J Mol Sci ; 19(11)2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30366418

RESUMO

Mirabilis himalaica (Edgew.) Heimerl is one of the most important genuine medicinal plants in Tibet, in which the special plateau habitat has been associated with its excellent medicinal quality and efficacy. However, the mechanisms by which environmental factors affect biosynthesis of secondary metabolic components remain unclear in this species. In this study, RNA sequencing and iTRAQ (isobaric Tags for Relative and Absolute Quantification) techniques were used to investigate the critical molecular "events" of rotenoid biosynthesis responding to UV-B radiation, a typical plateau ecological factor presented in native environment-grown M. himalaica plants. A total of 3641 differentially expressed genes (DEGs) and 106 differentially expressed proteins (DEPs) were identified in M. himalaica between UV-B treatment and control check (CK). Comprehensive analysis of protein and transcript data sets resulted in 14 and 7 DEGs from the plant hormone signal transduction and phosphatidylinositol signaling system pathways, respectively, being significantly enriched. The result showed that the plant hormone signal transduction and phosphatidylinositol signaling system might be the key metabolic strategy of UV-B radiation to improve the biosynthesis of rotenoid in M. himalaica. At same time, most of the DEGs were associated with auxin and calcium signaling, inferring that they might drive the downstream transmission of these signal transduction pathways. Regarding those pathways, two chalcone synthase enzymes, which play key roles in the biosynthesis of rotenoid that were thought as the representative medicinal component of M. himalaica, were significantly upregulated in UV-B radiation. This study provides a theoretical basis for further exploration of the adaptation mechanism of M. himalaica to UV-B radiation, and references for cultivation standardization.


Assuntos
Mirabilis/metabolismo , Mirabilis/efeitos da radiação , Extratos Vegetais/análise , Proteômica/métodos , Transcriptoma/genética , Raios Ultravioleta , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Fosfatidilinositóis/metabolismo , Reguladores de Crescimento de Plantas/metabolismo
17.
Zhongguo Zhong Yao Za Zhi ; 43(11): 2264-2260, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29945376

RESUMO

Artemisinin is a preferred medicine in the treatment of malaria. In this study, AaCMK, a key gene involved in the upstream pathway of artemisinin biosynthesis, was cloned and characterized from Artemisia annua for the first time. The full-length cDNA of AaCMK was 1 462 bp and contained an ORF of 1 197 bp that encoded a 399-anomo-acid polypeptide. Tissue expression pattern analysis showed that AaCMK was expressed in leaves, flowers, roots and stems, but with higher expression level in glandular secretory trichomes. In addition, the expression of AaCMK was markedly increased after MeJA treatment. Subcellular localization showed that the protein encoded by AaCMK was localized in chloroplast. Overexpression of AaCMK in Arabidopsis increased the contents of chlorophyll a, chlorophyll b and carotenoids. These results suggest that AaCMK plays an important role in the biosynthesis of terpenoids in A. annua and this research provids a candidate gene that could be used for engineering the artemisinin biosynthesis.


Assuntos
Artemisia annua/genética , Proteínas de Plantas/genética , Artemisia annua/enzimologia , Artemisininas , Clorofila A , Clonagem Molecular
18.
Biotechnol Appl Biochem ; 64(3): 305-314, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-26988377

RESUMO

Previous publications reported that the artemisinin level was increased in Artemisia annua following a night-frost period. However, the molecular mechanism was not clear. In this study, we found that exogenous jasmonate (JA) effectively enhanced the freezing tolerance of A. annua. The JA biosynthetic genes (LOX1, LOX2, allene oxide cyclase [AOC], and jasmonate resistant 1 [JAR1]) were induced by cold stress, leading to an increase in endogenous JA in cold-treated A. annua. Increased endogenous JA enhanced the expression of three JA-responsive transcription factors, ethylene response factor 1, ethylene response factor 2, and octadecanoid-responsive AP2/ERF, all of which were reported to transcriptionally activate the expression of artemisinin biosynthetic genes, such as amorpha-4,11-diene synthase (ADS), CYP71AV1, DBR2, and aldehyde dehydrogenase 1 (ALDH1). Furthermore, the expression levels of the four artemisinin biosynthetic genes were also significantly increased under cold stress. Consequently, the levels of artemisinin and related secondary metabolites, such as dihydroartemisinic acid, artemisinin B, and artemisinic acid, were increased in A. annua under cold stress. Our study points to a molecular mechanism in which the production of artemisinin is regulated by cold stress in A. annua.


Assuntos
Artemisia annua/metabolismo , Artemisininas/metabolismo , Resposta ao Choque Frio/fisiologia , Ciclopentanos/metabolismo , Lactonas/metabolismo , Oxilipinas/metabolismo , Artemisia annua/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética
19.
Biotechnol Appl Biochem ; 64(6): 902-910, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27311624

RESUMO

In recent years, although several related genes had been cloned and characterized, the role of aldehyde dehydrogenase 1 (ALDH1), the newly cloned gene involved in artemisinin biosynthesis pathway, is still not clear. In this study, a 2,100-bp ALDH1 promoter region fused with GUS reporter gene was stably transferred into Arabidopsis thaliana. Histochemical staining showed the methyl jasmonate (MeJA) and wounding treatment induced the GUS gene expression specifically in the trichomes of transgenic A. thaliana, consistent with the results that the expression level of ALDH1 gene was increased in the A. annua under MeJA and wounding treatments. Two RAA motifs (AP2/ERF binding site) but no W box (WRKY binding site) motif were identified in the ALDH1 promoter by the analysis through PLACE and plantCARE. Through the dual luciferase reporter assay, we revealed that both AaORA and AaERF2, rather than AaWRKY1, could activate the expression of ALDH1 promoter. Our study shed light on the in-depth understanding of the role of ALDH1 in artemisinin biosynthesis.


Assuntos
Artemisia annua/enzimologia , Isoenzimas/genética , Regiões Promotoras Genéticas/genética , Retinal Desidrogenase/genética , Família Aldeído Desidrogenase 1 , Clonagem Molecular , DNA de Plantas/genética
20.
Yao Xue Xue Bao ; 52(1): 172-9, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29911833

RESUMO

Tropane alkaloids are anticholinergic drugs widely used clinically. Biosynthesis of tropane alkaloids in planta involves a step of transamination of phenylalanine. Based on the sequenced transcriptomes of lateral roots and leaves of Hyoscyamus niger, we found three annotated aromatic amino acid aminotransferases, which were respectively named HnArAT1, HnArAT2 and HnArAT3. Sequence analysis showed that HnArAT3 had highest similarity with the reported Atropa belladonna Ab Ar AT4, which was involved in tropane alkaloid(TA) to provide the precursor of the phenyllactic acid moiety. Tissue expression pattern analysis indicated that HnArAT3 was specifically expressed in lateral roots, where is the organ synthesizing tropane alkaloids. Then, method of virus induced gene silencing (VIGS) was used to characterize the function of HnArAT3 in H. niger. Gene expression analysis given by real-time quantitative PCR showed that all the transgenic lines had lower expression levels of HnArAT3 than the non-transgenic control, and HPLC analysis of alkaloids demonstrated significant decrease in the contents of hyoscyamine, anisodamine and scopolamine in planta. These results suggested that HnArAT3 was involved in the phenyllactic acid branch of TA biosynthetic pathway. Molecular cloning and functional identification of HnArAT3 laid the foundation for further understanding of TA biosynthesis and metabolic regulation, and also provided a new candidate gene for engineering biosynthetic pathway of tropane alkaloids.


Assuntos
Alcaloides/biossíntese , Hyoscyamus/genética , Proteínas de Plantas/genética , Transaminases/genética , Tropanos/metabolismo , Atropa belladonna , Vias Biossintéticas , Antagonistas Colinérgicos , Clonagem Molecular , Hiosciamina , Hyoscyamus/enzimologia , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Escopolamina , Alcaloides de Solanáceas
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