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1.
Plant Physiol Biochem ; 167: 970-979, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34571390

RESUMO

Tea trees have a high demand for nitrogen (N) fertilizer to improve the yield and quality of tea. In this research, transcriptome analysis revealed the effect of N starvation and resupply upon N uptake in tea plants. We identified 4098 differentially expressed genes (DEGs) that were significantly enriched in amino acid and N metabolism and were extensively mapped to the tea genome. The CsNRT gene family plays vital roles in the nitrogen uptake of tea plants. The full CDS sequences of CsNRT1.1, CsNRT1.2, CsNRT1.5, CsNRT1.7, CsNRT2.4, CsNRT2.5, CsNRT3.1 and CsNRT3.2 were cloned. One-year-old cutting seedlings of Zhongcha302 (ZC302) were selected for hydroponic culture and were used for gene expression analysis. The seedlings were resupplied with 0.2 and 2 mM N after N starvation. The results of the gene expression under different N treatments and in various tissues indicated that the expression of CsNRT2.4 was highly expressed in tea roots and was greatly induced by N. Overexpressed CsNRT2.4 in transgenic Arabidopsis thaliana increased the root lengths and fresh weights and improved the NO3- uptake rate in the Arabidopsis roots at a low NO3- level. Thus, we inferred that CsNRT2.4 was a key gene for N uptake in tea plant roots. This study provides new insights into the molecular mechanisms of tea plant responses to N resupply and reveals hub genes for improving nitrogen usage efficiency (NUE) in tea plants.


Assuntos
Camellia sinensis , Nitrogênio , Camellia sinensis/genética , Camellia sinensis/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Nitrogênio/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Chá , Transcriptoma
2.
Molecules ; 26(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34443390

RESUMO

Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is producing a large number of infections and deaths globally, the development of supportive and auxiliary treatments is attracting increasing attention. Here, we evaluated SARS-CoV-2-inactivation activity of the polyphenol-rich tea leaf extract TY-1 containing concentrated theaflavins and other virucidal catechins. The TY-1 was mixed with SARS-CoV-2 solution, and its virucidal activity was evaluated. To evaluate the inhibition activity of TY-1 in SARS-CoV-2 infection, TY-1 was co-added with SARS-CoV-2 into cell culture media. After 1 h of incubation, the cell culture medium was replaced, and the cells were further incubated in the absence of TY-1. The viral titers were then evaluated. To evaluate the impacts of TY-1 on viral proteins and genome, TY-1-treated SARS-CoV-2 structural proteins and viral RNA were analyzed using western blotting and real-time RT-PCR, respectively. TY-1 showed time- and concentration-dependent virucidal activity. TY-1 inhibited SARS-CoV-2 infection of cells. The results of western blotting and real-time RT-PCR suggested that TY-1 induced structural change in the S2 subunit of the S protein and viral genome destruction, respectively. Our findings provided basic insights in vitro into the possible value of TY-1 as a virucidal agent, which could enhance the current SARS-CoV-2 control measures.


Assuntos
COVID-19/virologia , Polifenóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Chá/química , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , COVID-19/tratamento farmacológico , COVID-19/metabolismo , Camellia sinensis/metabolismo , Catequina/química , Catequina/farmacologia , Linhagem Celular , Chlorocebus aethiops , Genoma Viral/efeitos dos fármacos , Humanos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Polifenóis/isolamento & purificação , SARS-CoV-2/metabolismo , Células Vero , Carga Viral/efeitos dos fármacos
3.
J Agric Food Chem ; 69(35): 10069-10081, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34410120

RESUMO

Many studies have shown that phenolic compounds such as lignin and flavonoids enhance plant resistance. Tea plants are rich in flavonoid compounds. Whether these compounds are related to tea plant resistance is unclear. In this study, an interesting conclusion was drawn on the basis of experimental results: in response to abiotic stress (except for sucrose treatment), gene expression was increased in the phenylpropanoid and lignin pathways and was reduced in the flavonoid pathway in tea plants. CsHCTs, the genes located at the branch point of the lignin and flavonoid pathways, are most suitable for regulating the ratio of carbon flow in the lignin pathway and flavonoid synthesis. Enzymatic and genetic modification experiments proved that CsHCTs encode hydroxycinnamoyl-coenzyme A:shikimate/quinate hydroxycinnamoyl transferase in vitro and in vivo. Furthermore, the genetic modification results showed that the contents of phenolic acids and lignin were increased in tobacco and Arabidopsis plants overexpressing CsHCTs, whereas the content of flavonol glycosides was decreased. Both types of transgenic plants showed resistance to many abiotic stresses and bacterial infections. We speculate that CsHCTs participate in regulation of the metabolic flow of carbon from the flavonoid pathway to the chlorogenic acid, caffeoylshikimic acid, and lignin pathways to increase resistance to biotic and abiotic stresses.


Assuntos
Arabidopsis , Camellia sinensis , Arabidopsis/genética , Arabidopsis/metabolismo , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Chá
4.
J Agric Food Chem ; 69(34): 10002-10016, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34406741

RESUMO

Theanine and flavonoids (especially proanthocyanidins) are the most important and abundant secondary metabolites synthesized in the roots of tea plants. Nitrogen promotes theanine and represses flavonoid biosynthesis in tea plant roots, but the underlying mechanism is still elusive. Here, we analyzed theanine and flavonoid metabolism in tea plant roots under nitrogen deficiency and explored the regulatory mechanism using proteome and ubiquitylome profiling together with transcriptome data. Differentially expressed proteins responsive to nitrogen deficiency were identified and found to be enriched in flavonoid, nitrogen, and amino acid metabolism pathways. The proteins responding to nitrogen deficiency at the transcriptional level, translational level, and both transcriptional and translational levels were classified. Nitrogen-deficiency-responsive and ubiquitinated proteins were further identified. Our results showed that most genes encoding enzymes in the theanine synthesis pathway, such as CsAlaDC, CsGDH, and CsGOGATs, were repressed by nitrogen deficiency at transcriptional and/or protein level(s). While a large number of enzymes in flavonoid metabolism were upregulated at the transcriptional and/or translational level(s). Importantly, the ubiquitylomic analysis identified important proteins, especially the hub enzymes in theanine and flavonoid biosynthesis, such as CsAlaDC, CsTSI, CsGS, CsPAL, and CsCHS, modified by ubiquitination. This study provided novel insights into the regulation of theanine and flavonoid biosynthesis and will contribute to future studies on the post-translational regulation of secondary metabolism in tea plants.


Assuntos
Camellia sinensis , Nitrogênio , Camellia sinensis/genética , Camellia sinensis/metabolismo , Flavonoides , Regulação da Expressão Gênica de Plantas , Glutamatos , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Chá
5.
Nat Genet ; 53(8): 1250-1259, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34267370

RESUMO

Tea is an important global beverage crop and is largely clonally propagated. Despite previous studies on the species, its genetic and evolutionary history deserves further research. Here, we present a haplotype-resolved assembly of an Oolong tea cultivar, Tieguanyin. Analysis of allele-specific expression suggests a potential mechanism in response to mutation load during long-term clonal propagation. Population genomic analysis using 190 Camellia accessions uncovered independent evolutionary histories and parallel domestication in two widely cultivated varieties, var. sinensis and var. assamica. It also revealed extensive intra- and interspecific introgressions contributing to genetic diversity in modern cultivars. Strong signatures of selection were associated with biosynthetic and metabolic pathways that contribute to flavor characteristics as well as genes likely involved in the Green Revolution in the tea industry. Our results offer genetic and molecular insights into the evolutionary history of Camellia sinensis and provide genomic resources to further facilitate gene editing to enhance desirable traits in tea crops.


Assuntos
Camellia sinensis/genética , Genoma de Planta , Haplótipos , Proteínas de Plantas/genética , Alelos , Evolução Biológica , Camellia sinensis/metabolismo , Produtos Agrícolas/genética , Domesticação , Regulação da Expressão Gênica de Plantas , Introgressão Genética , Variação Genética , Genética Populacional , Filogenia , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único
6.
Plant Physiol Biochem ; 166: 668-676, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34214777

RESUMO

Selenium (Se) is an essential element for human health and an important nutrient for plant growth. Selenite is the main form of Se available to plants in acidic soils. Previous studies have shown that phosphate transporters (PTHs) participate in selenite uptake in plants. Research on the PHT gene family is therefore vital for production of Se-rich products. Here, 23 CsPHT genes were identified in the tea (Camellia sinensis) genome and renamed based on homology with AtPHT genes in Arabidopsis thaliana. The CsPHT genes were divided into four subfamilies: PHT1, PHT3, PHT4, and PHO, containing nine, three, six, and five genes, respectively. Phylogenetic analysis indicated that fewer duplication events occurred in tea plants than in A. thaliana, rice, apple, and poplar. Genes in the same subfamily tended to share similar gene structures, conserved motifs, and potential functions. CsPHT genes were differentially expressed in various tissues and in roots under different Se levels, suggesting key roles in selenite uptake, translocation, and homeostasis. The results illuminate the contributions of CsPHT genes to selenite supply in tea plants, and lay a foundation for follow-up studies on their potential functions in this plant species.


Assuntos
Camellia sinensis , Camellia sinensis/genética , Camellia sinensis/metabolismo , Família , Regulação da Expressão Gênica de Plantas , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Selenioso , Chá
7.
Plant Physiol Biochem ; 166: 849-856, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34229165

RESUMO

γ-Aminobutyric acid (GABA), a signal molecule, is regarded as the intersection node of carbon and nitrogen metabolism, and its contributions to flavonoid metabolism in tea plant growth and development remain unclear. The correlation between the GABA shunt and flavonoid metabolism in tea plants is worth to explore. Secondary metabolites and their correlations with the taste of tea soup made from tea plants (Camellia sinensis) during different seasons were investigated. Related secondary metabolites and transcript profiles of genes encoding enzymes in the GABA shunt, flavonoid pathway and polyamine biosynthesis were measured throughout the tea plant growth seasons and after exogenous GABA applications. In addition, the abundance of differentially expressed proteins was quantified after treatments with or without exogenous GABA. The tea leaves showed the highest metabolite concentrations in spring season. CsGAD, CsGABAT, CsSPMS, CsODC, CsF3H and CsCHS were found to be important genes in the GABA and anthocyanin biosynthesis pathways. GABA and anthocyanin concentrations showed a positive correlation, to some extent, CsF3H and CsCHS played important roles in the GABA and anthocyanin biosynthesis.


Assuntos
Camellia sinensis , Camellia sinensis/metabolismo , Flavonoides , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Chá , Ácido gama-Aminobutírico
8.
J Proteomics ; 247: 104337, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34298183

RESUMO

The aim of this work was to gain insight into the molecular mechanisms underlying the effect of fulvic acid on drought-exposed tea plants. We performed proteomic analysis of fulvic acid-treated tea leaves from the target plants using tandem mass tag quantitative labeling technology and compared the results with those of a previous transcriptomic analysis. We identified 48 and 611 differentially abundant proteins in the leaves of tea plants treated with fulvic acid compared with the control under mild and severe drought, respectively. Comparative analysis showed that, under severe drought, 55 genes had similar expression patterns at the transcriptome and proteome levels, such as PAL, GBE, GBSS and bAS. Bioinformatic analysis revealed that those genes were mainly related to the starch and sucrose metabolism, phenylpropanoid biosynthesis and triterpenoid biosynthesis. SIGNIFICANCE: This study broadens the understanding of the molecular mechanisms underlying the improved drought resistance seen in tea plants in the presence of fulvic acid and provides a basis for further research on the genomics of drought tolerance in these plants. In addition, these findings could be used to develop new guidance strategies for improved drought management systems in tea plantation.


Assuntos
Camellia sinensis , Secas , Benzopiranos , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Metabolismo Secundário , Amido , Sacarose , Chá , Transcriptoma
9.
Biomolecules ; 11(7)2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201466

RESUMO

Nitric oxide (NO) as a momentous signal molecule participates in plant reproductive development and responds to various abiotic stresses. Here, the inhibitory effects of the NO-dominated signal network on the pollen tube growth of Camellia sinensis under low temperature (LT) were studied by microRNA (miRNA) omics analysis. The results showed that 77 and 71 differentially expressed miRNAs (DEMs) were induced by LT and NO treatment, respectively. Gene ontology (GO) analysis showed that DEM target genes related to microtubules and actin were enriched uniquely under LT treatment, while DEM target genes related to redox process were enriched uniquely under NO treatment. In addition, the target genes of miRNA co-regulated by LT and NO are only located on the cell membrane and cell wall, and most of them are enriched in metal ion binding and/or transport and cell wall organization. Furthermore, DEM and its target genes related to metal ion binding/transport, redox process, actin, cell wall organization and carbohydrate metabolism were identified and quantified by functional analysis and qRT-PCR. In conclusion, miRNA omics analysis provides a complex signal network regulated by NO-mediated miRNA, which changes cell structure and component distribution by adjusting Ca2+ gradient, thus affecting the polar growth of the C. sinensis pollen tube tip under LT.


Assuntos
Camellia sinensis/genética , Temperatura Baixa , MicroRNAs/genética , Óxido Nítrico/farmacologia , Tubo Polínico/genética , Análise de Sequência de RNA/métodos , Camellia sinensis/metabolismo , Redes Reguladoras de Genes/efeitos dos fármacos , Redes Reguladoras de Genes/fisiologia , MicroRNAs/metabolismo , Tubo Polínico/efeitos dos fármacos , Tubo Polínico/metabolismo
10.
BMC Plant Biol ; 21(1): 337, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271878

RESUMO

BACKGROUND: Pesticide residue and its poor utilization remains problematic in agricultural development. To address the issue, a nano-pesticide has been developed by incorporating pesticide acetamiprid in porous silica nanoparticles. RESULTS: This nano-pesticide had an acetamiprid loading content of 354.01 mg g-1. Testing LC50 value against tea aphids of the commercial preparation was three times that of the nano-pesticide. In tea seedlings (Camellia sinensis L.), acetamiprid was transported upward from the stem to the young leaves. On day 30, the average retained concentrations in tea leaves treated with the commercial preparation were about 1.3 times of that in the nano-pesticide preparation. The residual concentrations of dimethyl-acetamiprid in leaves for plants treated with the commercial preparation were about 1.1 times of that in the nano-pesticide preparation. Untargeted metabolomics of by LC-MS on the young leaves of tea seedlings under nano-pesticide and commercial pesticide treatments showed significant numbers of differentially expressed metabolites (P < 0.05 and VIP > 1). Between the nano-pesticide treatment group and the commercial preparation treatment group there were 196 differentially expressed metabolites 2 h after treatment, 200 (7th day), 207 (21st day), and 201 (30th day) in negative ion mode, and 294 (2nd h), 356 (7th day), and 286 (30th day) in positive ion mode. Preliminary identification showed that the major differentially expressed metabolites were glutamic acid, salicylic acid, p-coumaric acid, ribonic acid, glutamine, naringenin diglucoside, sanguiin H4, PG (34:2) and epiafzelechin. CONCLUSIONS: This work demonstrated that our nano-pesticide outperformed the conventional pesticide acetamiprid in terms of insecticidal activity and pesticide residue, and the absorption, transportation and metabolism of nano-pesticide in tea plant were different, which pave a new pathway for pest control in agricultural sector.


Assuntos
Camellia sinensis/metabolismo , Inseticidas , Nanopartículas , Neonicotinoides , Folhas de Planta/metabolismo , Neonicotinoides/metabolismo , Resíduos de Praguicidas
11.
Molecules ; 26(11)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072521

RESUMO

Tea (Camellia sinensis) is one of the most important cash crops in the world. Theanine, as an important amino acid component in tea, is a key quality index for excellent tea quality and high economic value. People increase theanine accumulation in tea mainly through the application of nitrogen fertilizer, shading and pruning. However, these methods are not effective. In this study, we treated tea buds with a 100 µM solution of GA3 containing 1‰ tween-20, investigated the effects of GA3 on theanine accumulation, bud yield, chlorophyll fluorescence parameters and expression level of theanine biosynthesis pathway genes in tea plant by qPCR, LC-MS/MS etc. Results showed that change trends of theanine and GA3 was extremely positively correlated with each other. Exogenous GA3 upregulated the expression level of theanine biosynthesis pathway genes, caused an increase of theanine content (mg·g-1) by 27% in tea leaves compared with Mock, and accelerated the germination of buds and elongation of shoots, which lead to a significant increase of tea yield by 56% (w/w). Moreover, the decrease of chlorophyll contents, photochemical quenching coefficient (qP) and relative electron transport rate (rETR) under GA3 treatment suggested that GA3 reduced photosynthesis in the tender tea leaves, indicating that the decline of carbon assimilation in tea plants was conducive to the nitrogen metabolism, and it was beneficial to the accumulation of theanine. This study provided a new technical and theoretical support for the precise control of tea quality components and phenophase.


Assuntos
Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Giberelinas/farmacologia , Folhas de Planta/metabolismo , Chá/metabolismo , Aminoácidos/química , Clorofila/química , Cromatografia Líquida , Giberelinas/química , Glutamatos/química , Nitrogênio/metabolismo , Fotossíntese , Proteínas de Plantas/genética , Brotos de Planta , Reação em Cadeia da Polimerase , Espectrometria de Massas em Tandem
12.
J Sci Food Agric ; 101(13): 5678-5687, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33792039

RESUMO

BACKGROUND: The proper growth and development of tea plants requires moderately acidic soils and relatively low calcium levels, and excessive calcium at high pH can damage tea plant roots. To reveal the effects of calcium on the responses of tea plant to three pH levels (3.5, 5.0 and 6.5), a repeated test of two factors was designed. RESULTS: Root growth and elemental analysis indicated that excessive calcium improved the growth of tea roots at low pH conditions, whereas it did not harm the growth of tea roots under normal and high pH conditions, especially at pH 6.5. Excessive calcium antagonized the absorption and utilization of magnesium by tea plants. Gas chromatography-mass spectrometry results showed that the addition of Ca2+ resulted in the primary metabolism in roots being more active at a low pH level. By contrast, it had obvious adverse effects on the accumulation of root metabolites with high calcium treatment at normal or high pH. Differential metabolites identified using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry indicated that flavonoids demonstrated the largest number of changes, and their biosynthesis was partially enriched with excessive calcium at low and high pH conditions, whereas it was down-regulated under normal pH conditions. Kaempferol 3-(2'-rhamnosyl-6'-acetylgalactoside) 7-rhamnoside, quercetin 3-(6'-sinapoylsophorotrioside) and delphinidin 3-(3'-p-coumaroylglucoside) showed the greatest increase. The results of gene expression related to root growth and calcium regulation were consistent with root growth and root metabolism. CONCLUSION: The overall results demonstrated that high Ca concentrations further aggravate the detrimental effects of high pH to tea roots. However, it is interesting that excessive calcium reduced the harm of a low pH on tea root growth to some extent. © 2021 Society of Chemical Industry.


Assuntos
Cálcio/metabolismo , Camellia sinensis/metabolismo , Proteínas de Plantas/metabolismo , Transporte Biológico , Camellia sinensis/genética , Camellia sinensis/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Magnésio/metabolismo , Metabolômica , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Solo/química
13.
J Sci Food Agric ; 101(14): 5992-6000, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33851415

RESUMO

BACKGROUND: Tolfenpyrad and dinotefuran are two representative pesticides used for pest control in tea gardens. Their application may bring about a potential risk to the health of consumers. Therefore, it is essential to investigate the residue behavior, transfer and risk assessment of tolfenpyrad, dinotefuran and metabolites from tea garden to teacup. RESULTS: An effective analytical method was established and validated to simultaneously determine tolfenpyrad, dinotefuran and its metabolites (DN and UF) in tea. The average recoveries of tolfenpyrad, dinotefuran, DN and UF were in the range 72.1-106.3%, with relative standard deviations lower than 11.8%. On the basis of the proposed method, the dissipation of tolfenpyrad and dinotefuran in fresh tea leaves followed first-order kinetics models with half-lives of 4.30-7.33 days and 4.65-5.50 days, respectively. With application amounts of 112.5-168.75 g a.i. ha-1 once or twice, the terminal residues of tolfenpyrad and total dinotefuran in green tea were lower than 19.6 and 7.13 mg kg-1 , respectively, and below their corresponding maximum residue limits . The leaching rates of tolfenpyrad and total dinotefuran during the tea brewing were in the ranges 1.4-2.3% and 93.7-98.1%, respectively. CONCLUSION: Tolfenpyrad and dinotefuran in tea were easily degraded. The RQc and RQa values for tolfenpyrad were 37.6% and 5.4%, which were much higher than for dinotefuran at 24.7% and 0.84%, respectively. The data indicated that there was no significant health risk in tea for consumers at the recommended dosages. The results provide scientific data regarding the reasonable use of tolfenpyrad and dinotefuran aiming to ensure safe tea consuption. © 2021 Society of Chemical Industry.


Assuntos
Camellia sinensis/crescimento & desenvolvimento , Guanidinas/química , Neonicotinoides/química , Nitrocompostos/química , Resíduos de Praguicidas/química , Pirazóis/química , Chá/química , Camellia sinensis/química , Camellia sinensis/metabolismo , Qualidade de Produtos para o Consumidor , Culinária , Contaminação de Alimentos/análise , Guanidinas/metabolismo , Humanos , Cinética , Neonicotinoides/metabolismo , Nitrocompostos/metabolismo , Resíduos de Praguicidas/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Pirazóis/metabolismo , Medição de Risco , Chá/metabolismo
14.
Planta ; 253(5): 93, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33826012

RESUMO

MAIN CONCLUSION: Genome-wide identification, expression analysis of the MYC family in Camellia sinensis, and potential functional characterization of CsMYC2.1 have laid a solid foundation for further research on CsMYC2.1 in jasmonate (JA)-mediated response. Myelocytomatosis (MYC) of basic helix-loop-helix (bHLH) plays a major role in JA-mediated plant growth and developmental processes through specifically binding to the G-box in the promoters of their target genes. In Camellia sinensis, studies on the MYC gene family are limited. Here, we identified 14 C. sinensis MYC (CsMYC) genes, and further analyzed the evolutionary relationship, gene structure, and motif pattern among them. The expression patterns of these CsMYC genes in different tissues suggested their important roles in diverse function in tea plant. Four MYC transcription factors with the highest homology to MYC2 in Arabidopsis were localized in the nucleus. Two of them, named CsMYC2.1 and CsMYC2.2, exhibited transcriptional self-activating activity, and, therefore, could significantly activate the promoter containing G-box motif, whereas CsJAM1.1 and CsJAM1.2 lack the transcriptional self-activating activity, indirectly mediating the JA pathway through interacting with CsMYC2.1 and CsMYC2.2. Furthermore, Yeast Two-Hybrid (Y2H) and Bimolecular Fluorescent Complimentary (BiFC) assays showed that CsMYC2.1 could interact with CsJAZ3/7/8 proteins. Genetically, the complementation of CsMYC2.1 in myc2 mutants conferred the ability to restore the sensitivity to JA signals. The results provide a comprehensive characterization of the 14 CsMYCs in C. sinensis, establishing a solid foundation for further research on CsMYCs in JA-mediated response.


Assuntos
Proteínas de Arabidopsis , Camellia sinensis , Proteínas de Arabidopsis/metabolismo , Camellia sinensis/genética , Camellia sinensis/metabolismo , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Oxilipinas , Plantas Geneticamente Modificadas/metabolismo , Proteínas Repressoras/genética , Fatores de Transcrição/genética
15.
Int J Mol Sci ; 22(8)2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33919599

RESUMO

The C2H2-zinc finger protein (C2H2-ZFP) is essential for the regulation of plant development and widely responsive to diverse stresses including drought, cold and salt stress, further affecting the late flavonoid accumulation in higher plants. Tea is known as a popular beverage worldwide and its quality is greatly dependent on the physiological status and growing environment of the tea plant. To date, the understanding of C2H2-ZFP gene family in Camellia sinensis [L.] O. Kuntze is not yet available. In the present study, 134 CsC2H2-ZFP genes were identified and randomly distributed on 15 chromosomes. The CsC2H2-ZFP gene family was classified into four clades and gene structures and motif compositions of CsC2H2-ZFPs were similar within the same clade. Segmental duplication and negative selection were the main forces driving the expansion of the CsC2H2-ZFP gene family. Expression patterns suggested that CsC2H2-ZFPs were responsive to different stresses including drought, salt, cold and methyl jasmonate (MeJA) treatment. Specially, several C2H2-ZFPs showed a significant correlation with the catechins content and responded to the MeJA treatment, which might contribute to the tea quality and specialized astringent taste. This study will lay the foundations for further research of C2H2-type zinc finger proteins on the stress responses and quality-related metabolites accumulation in C. sinensis.


Assuntos
Dedos de Zinco CYS2-HIS2/fisiologia , Camellia sinensis/metabolismo , Catequina/metabolismo , Proteínas de Plantas/metabolismo , Dedos de Zinco CYS2-HIS2/genética , Catequina/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética
16.
Mar Drugs ; 19(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808933

RESUMO

In this work, a non-toxic chitosan-based carrier was constructed via genipin activation and applied for the immobilization of tannase. The immobilization carriers and immobilized tannase were characterized using Fourier transform infrared spectroscopy and thermogravimetric analysis. Activation conditions (genipin concentration, activation temperature, activation pH and activation time) and immobilizations conditions (enzyme amount, immobilization time, immobilization temperature, immobilization pH, and shaking speed) were optimized. The activity and activity recovery rate of the immobilized tannase prepared using optimal activation and immobilization conditions reached 29.2 U/g and 53.6%, respectively. The immobilized tannase exhibited better environmental adaptability and stability. The immobilized tannase retained 20.1% of the initial activity after 12 cycles and retained 81.12% of residual activity after 30 days storage. The catechins composition analysis of tea extract indicated that the concentration of non-ester-type catechins, EGC and EC, were increased by 1758% and 807% after enzymatic treatment. Biological activity studies of tea extract revealed that tea extract treated with the immobilized tannase possessed higher antioxidant activity, higher inhibitory effect on α-amylase, and lower inhibitory effect on α-glucosidase. Our results demonstrate that chitosan activated with genipin could be an effective non-toxic carrier for tannase immobilization and enhancing biological activities of tea extract.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis , Hidrolases de Éster Carboxílico/metabolismo , Quitosana/química , Portadores de Fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , Iridoides/química , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Camellia sinensis/metabolismo , Hidrolases de Éster Carboxílico/química , Composição de Medicamentos , Estabilidade Enzimática , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Temperatura , Fatores de Tempo , alfa-Amilases/metabolismo
17.
Chem Biodivers ; 18(6): e2100132, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33928738

RESUMO

As an economically important crop, tea is widely cultivated in more than 50 countries and has numerous health benefits. Metabolomics has considerable advantages in the analysis of small molecules and has been widely used in tea science. We applied a metabolomic method to evaluate the dynamic changes in metabolites and pathways in the large-, middle- and small-leaf cultivars of Camellia sinensis (L.) Kuntze var. niaowangensis grown in the same area from Yunwu Mountain. The results indicate that flavonoid biosynthesis, stilbenoid, diarylheptanoid and gingerol biosynthesis, citrate cycle (TCA cycle), and propanoate metabolism may play important roles in the differences among cultivars. The levels of tea polyphenols, flavonoids and amino acids may impact the sensory properties of teas of different cultivars. Our results may help to elucidate the mechanism underlying the difference in tea quality and offer references for the breeding of high-quality tea cultivars.


Assuntos
Camellia sinensis/metabolismo , Metabolômica , Folhas de Planta/metabolismo , Camellia sinensis/química , Folhas de Planta/química
18.
J Agric Food Chem ; 69(11): 3415-3429, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33719427

RESUMO

The physiological and metabolic differences between shoot tips and roots of tea plants are significant, and understanding them is required for improvement of tea quality and plant growth. A high-quality full-length transcriptome sequencing on tea plant roots and shoot tips by PacBio SMRT technology was done to gain a further understanding. Approximately 160699 and 166120 full-length transcripts were recovered in roots and shoots, respectively, including 31232 and 41068 novel isoforms and 16960 and 26029 alternative splicing (AS) isoforms. These supported 21699 full-length reads and 31232 and 41068 novel transcripts from root and shoot, respectively, including 1679 long noncoding RNAs (lncRNAs) and 2772 fusion transcripts, which significantly upgrade the Camellia sinensis genome annotation. The respective 6475 and 6981 transcripts in roots and shoots differ in 3'-untranslated regions. Meanwhile, extensive analyses of novel transcripts, ASs, and lncRNAs also revealed a large number of ASs and lincRNAs closely related to the regulation of characteristic secondary metabolites including catechins, theanine, and caffeine. Finally, a root-specific CsMYB6 was characterized to regulate theanine biosynthesis by genetic and molecular analyses. CsMYB6 directly bound to and activate the promoter of theanine synthetase gene (CsTSI). The study lays a foundation for the further investigation of metabolic genomics and regulation in tea plants.


Assuntos
Camellia sinensis , Camellia sinensis/genética , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Glutamatos/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Chá
19.
J Agric Food Chem ; 69(11): 3401-3414, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33719437

RESUMO

Tea leaves contain an extraordinarily high level of flavonoids that contribute to tea health benefits and flavor characteristics, but the regulatory mechanism of ambient ultraviolet B (UV-B) on tea flavonoid enrichment remains unclear. Here, we report that ambient UV-B modulates tea quality by inducing a metabolic flux in flavonoid biosynthesis. UV-B absence decreased bitter- and astringent-tasting flavonol glycosides (kaempferol-7-O-glucoside, myricetin-3-O-glucoside, and quercetin-7-O-glucoside) but increased non-galloylated catechins. Conversely, supplementary UV-B increased flavonols and decreased catechins in tea leaves. These responses were achieved via CsHY5, which mediates the UV-B-induced MYB12 activation and binds to the promoters of flavonoid biosynthetic genes (CsFLS, CsLARa, and CsDFRa), leading to flavonoid changes. Transcriptomic data indicated that UV-B-induced tea flavonoid regulation is responsive to multiple biotic and abiotic environmental stresses. These findings improve our understanding of light-regulated tea astringency and bitterness underlying shading effects and seasonal light changes and provide novel insights into tea cultivation management and processing.


Assuntos
Camellia sinensis , Camellia sinensis/metabolismo , Flavonoides , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Chá
20.
Int J Biol Macromol ; 179: 485-499, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33684430

RESUMO

Melatonin (MT) is a bioactive molecule that can regulate various developmental processes. Changes in lignin content play important roles in plant growth and development. Herein, quantitative analysis and histochemical staining showed that lignin content significantly increased over time, and melatonin treatment triggered the lignification at 8 and 16 d in tea leaves. The POD activity participated in lignin formation had also been significantly improved. The effect of melatonin on the increase of lignin content was attenuation over time. Sequencing results based on transcriptome at 8 and 16 d showed that 5273 and 3019 differentially expressed genes (DEGs) were identified in CK1 vs. MT1 and CK2 vs. MT2, respectively. A total of 67 DEGs were annotated to lignin biosynthesis, and 38 and 9 genes were significantly up-regulated under melatonin treatment, respectively. Some transcription factor genes such as MYB were also identified among the two pairwise comparisons, which might relate to lignin metabolism. Melatonin increased the degree of lignification in tea leaves by modifying the enzyme genes expression involved in lignin synthesis pathway. These results provide a reference for further study on the molecular mechanism of the dynamic changes of lignin content induced by melatonin treatment in tea plants.


Assuntos
Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lignina/biossíntese , Melatonina/farmacologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo
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