RESUMO
Ursolic acid has gradually attracted much attention due to its unique pharmacological activities and valuable market value in recent years. Currently, ursolic acid is mostly extracted from loquat leaves, but the plant extraction method has low yield and high cost, and chemical synthesis is not readily available, so the biosynthesis method provides a new source for ursolic acid. α-amyrin acts as the main precursor for the synthesis of ursolic acid, and its yield is positively correlated with ursolic acid yield. Oxidosqualene cyclase(OSC) belongs to a multigene family which can catalyze the common precursor 2,3-oxidosqualene to generate different types of triterpene backbones, and plays a decisive role in the synthesis of triterpenoids. However, there are fewer reported key genes catalyzing the synthesis of α-amyrin in medicinal plants, and the yield and proportion of α-amyrin in the catalyzed products have always been a focus of research. In this study, ItOSC2, MdOSC1, AaOSC2 and CrAS, four enzymes capable of catalyzing the production of α-amyrin from 2,3-oxidosqualene, were cloned from Iris tectorum, Malus domestica, Artemisia annua and Catharanthus roseus, subject to sequence alignment and phylogenetic tree analyses, and transformed into Saccharomyces cerevisiae as plasmids. After 7 days of fermentation, the yield and proportions of α-amyrin, ß-amyrin and ergosterol were measured. Finally, AaOSC2 with the best ability to catalyze the generation of α-amyrin was filtered out, providing a key gene element for the later construction of engineered yeast strains with high production of α-amyrin and ursolic acid.
Assuntos
Transferases Intramoleculares , Ácido Oleanólico , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Ácido Oleanólico/química , Ácido Oleanólico/biossíntese , Clonagem Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triterpenos/metabolismo , Triterpenos/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Filogenia , Triterpenos PentacíclicosRESUMO
High temperatures are a major stress factor that limit the growth of Pinellia ternata. WRKY proteins widely distribute in plants with the important roles in plant growth and stress responses. However, WRKY genes have not been identified in P. ternata thus far. In this study, five PtWRKYs with four functional subgroups were identified in P. ternata. One group III WRKY transcription factor, PtWRKY2, was strongly induced by high temperatures, whereas the other four PtWRKYs were suppressed. Analysis of transcription factor characteristics revealed that PtWRKY2 localized to the nucleus and specifically bound to W-box elements without transcriptional activation activity. Overexpression of PtWRKY2 increased the heat tolerance of Arabidopsis, as shown by the higher percentage of seed germination and survival rate, and the longer root length of transgenic lines under high temperatures compared to the wild-type. Moreover, PtWRKY2 overexpression significantly decreased reactive oxygen species accumulation by increasing the catalase, superoxide dismutase, and peroxidase activities. Furthermore, the selected heat shock-associated genes, including five transcription factors (HSFA1A, HSFA7A, bZIP28, DREB2A, and DREB2B), two heat shock proteins (HSP70 and HSP17.4), and three antioxidant enzymes (POD34, CAT1, and SOD1), were all upregulated in transgenic Arabidopsis. The study identifies that PtWRKY2 functions as a key transcriptional regulator in the heat tolerance of P. ternata, which might provide new insights into the genetic improvement of P. ternata.
Assuntos
Arabidopsis , Regulação da Expressão Gênica de Plantas , Pinellia , Proteínas de Plantas , Plantas Geneticamente Modificadas , Termotolerância , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Termotolerância/genética , Pinellia/genética , Pinellia/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Resposta ao Choque Térmico/genética , Temperatura AltaRESUMO
Medicinal plants are rich in a variety of secondary metabolites with therapeutic value. However, the yields of these metabolites are generally very low, making their extraction both time- and labour-consuming. Transcription factor (TF)-targeted secondary metabolic engineering can efficiently regulate the biosynthesis and accumulation of secondary metabolites in medicinal plants. v-Myb avian myeloblastosis viral oncogene homolog (MYB) TFs are involved in regulating various morphological and developmental processes, responses to stress, and the biosynthesis of secondary metabolites in plants. This review discusses the biological functions and transcription regulation mechanisms of MYB TFs and summarises the research progress concerning MYB TFs involved in the biosynthesis of representative active components. In the transcriptional regulatory network, MYB TFs regulate multiple synthase genes to mediate active ingredient biosynthesis. This study will serve as a reference for the in-depth analysis of the MYB TF family in medicinal plants.
RESUMO
Pinellia ternata (Thunb.) Briet., a valuable herb native to China, is susceptible to the "sprout tumble" phenomenon because of high temperatures, resulting in a significant yield reduction. However, the molecular regulatory mechanisms underlying the response of P. ternata to heat stress are not well understood. In this study, we integrated transcriptome and miRNAome sequencing to identify heat-response genes, microRNAs (miRNAs), and key miRNA-target pairs in P. ternata that differed between heat-stress and room-temperature conditions. Transcriptome analysis revealed extensive reprogramming of 4,960 genes across various categories, predominantly associated with cellular and metabolic processes, responses to stimuli, biological regulation, cell parts, organelles, membranes, and catalytic and binding activities. miRNAome sequencing identified 1,597 known/conserved miRNAs that were differentially expressed between the two test conditions. According to the analysis, genes and miRNAs associated with the regulation of transcription, DNA template, transcription factor activity, and sequence-specific DNA binding pathways may play a major role in the resistance to heat stress in P. ternata. Integrated analysis of the transcriptome and miRNAome expression data revealed 41 high-confidence miRNA-mRNA pairs, forming 25 modules. MYB-like proteins and calcium-responsive transcription coactivators may play an integral role in heat-stress resistance in P. ternata. Additionally, the candidate genes and miRNAs were subjected to quantitative real-time polymerase chain reaction to validate their expression patterns. These results offer a foundation for future studies exploring the mechanisms and critical genes involved in heat-stress resistance in P. ternata.
Assuntos
Resposta ao Choque Térmico , MicroRNAs , Pinellia , Plântula , Transcriptoma , Pinellia/genética , Pinellia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Resposta ao Choque Térmico/genética , Plântula/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de PlantasRESUMO
BACKGROUND: Lead is a persistent, ubiquitous pollutant whose historical sources have been largely addressed through regulation and voluntary actions. The United States (U.S.) has achieved significant decreases in children's blood lead levels (BLL) over the past 40 years; however, there is no known safe level of Pb exposure. Some communities continue to be disproportionately impacted by exposure to Pb, including Black children and families living in older homes. OBJECTIVE: To identify Ohio (OH) census tracts with children exposed to Pb and evaluate potential exposure determinants. METHODS: We obtained individual children's blood Pb data from 2005-2018 in OH. The percent of children with elevated BLL (EBLL) was calculated for OH census tracts using three blood Pb reference values (3.5, 5, and 10 µg/dL). Getis-Ord Gi* geospatial hotspot or top 20th percentile methodologies were then applied to identify "hotspots." Findings across multiple time periods and blood Pb reference values were evaluated and compared with existing Pb exposure indices and models. RESULTS: Consistency was observed across different blood Pb reference values, with the main hotspots identified at 3.5 µg/dL, also identified at 5 and 10 µg/dL. Substantial gains in public health were demonstrated, with the biggest decreases in the number of census tracts with EBLL observed between 2008-2010 and 2011-2013. Across OH, 355 census tracts (of 2850) were identified as hotspots across 17 locations, with the majority in the most populated cites. Generally, old housing and sociodemographic factors were indicators of these EBLL hotspots. A smaller number of hotspots were not associated with these exposure determinants. Variables of race, income, and education level were all strong predictors of hotspots. IMPACT STATEMENT: The Getis-Ord Gi* geospatial hotspot analysis can inform local investigations into potential Pb exposures for children living in OH. The successful application of a generalizable childhood blood Pb methodology at the census tract scale provides results that are more readily actionable. The moderate agreement of the measured blood Pb results with public Pb indices provide confidence that these indices can be used in the absence of available blood Pb surveillance data. While not a replacement for universal blood Pb testing, a consistent approach can be applied to identify areas where Pb exposure may be problematic.
Assuntos
Censos , Exposição Ambiental , Poluentes Ambientais , Chumbo , Ohio , Humanos , Chumbo/sangue , Chumbo/análise , Exposição Ambiental/análise , Pré-Escolar , Masculino , Feminino , Poluentes Ambientais/sangue , Criança , Lactente , Análise EspacialRESUMO
Pinellia ternata, a valuable Chinese herb, suffers yield reduction due to "sprout tumble" under high temperatures. However, the mechanisms underlying its high-temperature stress remain poorly understood. NAM, ATAF1/2, and CUC2 (NAC) transcription factors regulate plant tissue growth and abiotic stress. Hence, there has been no comprehensive research conducted on NAC transcription factors in P. ternata. We identified 98 PtNAC genes unevenly distributed across 13 chromosomes, grouped into 15 families via phylogenetic analysis. Gene expression analysis revealed diverse expression patterns of PtNAC genes in different tissue types. Further studies revealed that PtNAC5/7/17/35/43/47/57/66/86 genes were highly expressed in various tissues of P. ternata and induced by heat stress, among which PtNAC66 was up-regulated at the highest folds induced by heat temperature. PtNAC66 is a nuclear protein that can selectively bind to the cis-responsive region NACRS but lacks the ability to activate transcription in yeast. For further research, PtNAC66 was cloned and transgenic Arabidopsis was obtained. PtNAC66 overexpression increased high-temperature tolerance compared to wild-type plants. Transcriptome profiling demonstrated that overexpression of PtNAC66 led to significant modification of genes responsible for regulating binding, catalytic activity, transcription regulator activity and transporter activity response genes. Additionally, PtNAC66 was found to bind the promoters of CYP707A3, MYB102 and NAC055, respectively, and inhibited their expression, affecting the high-temperature stress response in Arabidopsis. Our research established the foundation for functional studies of PtNAC genes in response to high-temperature forcing by characterizing the P. ternata NAC gene family and examining the biological role of PtNAC66 in plant high-temperature tolerance.
Assuntos
Arabidopsis , Pinellia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Pinellia/genética , Pinellia/metabolismo , Temperatura , Filogenia , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismoRESUMO
Pinellia ternata is an important natural medicinal herb in China. However, it is susceptible to withering when exposed to high temperatures during growth, which limits its tuber production. Mitochondria usually function in stress response. The P . ternata mitochondrial (mt) genome has yet to be explored. Therefore, we integrated PacBio and Illumina sequencing reads to assemble and annotate the mt genome of P . ternata . The circular mt genome of P . ternata is 876 608bp in length and contains 38 protein-coding genes (PCGs), 20 tRNA genes and three rRNA genes. Codon usage, sequence repeats, RNA editing and gene migration from chloroplast (cp) to mt were also examined. Phylogenetic analysis based on the mt genomes of P . ternata and 36 other taxa revealed the taxonomic and evolutionary status of P . ternata . Furthermore, we investigated the mt genome size and GC content by comparing P . ternata with the other 35 species. An evaluation of non-synonymous substitutions and synonymous substitutions indicated that most PCGs in the mt genome underwent negative selection. Our results provide comprehensive information on the P . ternata mt genome, which may facilitate future research on the high-temperature response of P . ternata and provide new molecular insights on the Araceae family.
Assuntos
Genoma Mitocondrial , Pinellia , Plantas Medicinais , Pinellia/genética , Genoma Mitocondrial/genética , Filogenia , Plantas Medicinais/genética , TubérculosRESUMO
To identify U.S. lead exposure risk hotspots, we expanded upon geospatial statistical methods from a published Michigan case study. The evaluation of identified hotspots using five lead indices, based on housing age and sociodemographic data, showed moderate-to-substantial agreement with state-identified higher-risk locations from nine public health department reports (45-78%) and with hotspots of children's blood lead data from Michigan and Ohio (e.g., Cohen's kappa scores of 0.49-0.63). Applying geospatial cluster analysis and 80th-100th percentile methods to the lead indices, the number of U.S. census tracts ranged from â¼8% (intersection of indices) to â¼41% (combination of indices). Analyses of the number of children <6 years old living in those census tracts revealed the states (e.g., Illinois, Michigan, New Jersey, New York, Ohio, Pennsylvania, Massachusetts, California, Texas) and counties with highest potential lead exposure risk. Results support use of available lead indices as surrogates to identify locations in the absence of consistent, complete blood lead level (BLL) data across the United States. Ground-truthing with local knowledge, additional BLL data, and environmental data is needed to improve identification and analysis of lead exposure and BLL hotspots for interventions. While the science evolves, these screening results can inform "deeper dive" analyses for targeting lead actions.
RESUMO
BACKGROUND: High temperature and drought environments are important limiting factors for Pinellia ternata growth, whereas shading can promote growth by relieving these stresses. However, the mechanism of growth promotion by shading in P. ternata is unknown. Long non-coding RNAs (lncRNAs) play important roles in the plant's growth and environmental response, but few analyses of lncRNAs in P. ternata have been reported. METHODS: We performed lncRNAs analysis of P. ternata in response to shading using RNA-seq data from our previous studies. A total of 13,927 lncRNAs were identified, and 145 differentially expressed lncRNAs (DELs) were obtained from the comparisons of 5 days shade (D5S) vs. 5 days of natural light (D5CK), 20 days of shade (D20S) vs. 20 days of natural light (D20CK), D20S vs. D5S, and D20CK vs. D5CK. Of these, 119 DELs (82.07%) were generated from the D20S vs. D20CK comparison. RESULTS: Gene ontology (GO) analysis indicated that the reactive oxygen (ROS) metabolism and programmed cell death (PCD) processes might regulate shade-induced growth promotion. The "signal transduction" and "environmental adaptation" in the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used for lncRNA-mRNA regulatory network construction and showed that the lncRNAs might mediate P. ternata growth by regulating ROS accumulation and light signals. CONCLUSIONS: This study explores lncRNAs' functions and regulatory mechanisms related to P. ternata growth and lays a foundation for further research on P. ternata.
Assuntos
Pinellia , RNA Longo não Codificante , Pinellia/genética , Pinellia/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Perfilação da Expressão GênicaRESUMO
Drought is one of the major abiotic stresses limiting agricultural production, particularly for shallow-rooted plants like Pinellia ternata. It damages plants via oxidative burst, but this effect could be mitigated by catalase (CAT). However, no studies have been reported on CAT homologs in P. ternata, a drought-sensitive plant species. In the present study, a novel CAT gene, PtCAT2, was functionally characterized via overexpression in Arabidopsis and analysis of cis-elements in its promoter. The isolated CAT gene was 1479 bp and encoded a protein containing 242 amino acids. The protein contains the CAT activity motif and the heme-binding site of a typical CAT, and the subcellular analysis indicated that the protein localizes at the cytoplasm and membrane. Moreover, the quantitative real-time reverse transcription PCR indicated that PtCAT2 is expressed ubiquitously in P. ternata and is strongly induced by drought stress and abscisic acid (ABA) signals. PtCAT2 overexpression enhanced the drought tolerance of Arabidopsis, as shown by the 30% increase in plant survival and a five-fold- increase in CAT activity. Moreover, PtCAT2-transgenic plants increased superoxide dismutase and peroxidase activities and reduced malondialdehyde, membrane leakage, and hydrogen peroxide (H2O2) (P<0.05). Furthermore, PtCAT2-transgenic plants showed higher tolerance to oxidative stress caused by exogenous H2O2 and retained higher chlorophyll and water contents than the WT. The mitochondria function was better maintained as presented by the higher oxygen consumption rate in transgenics under drought stress (P<0.05). The endogenous CATs and drought response-related genes were also upregulated in transgenic lines under drought stress, indicating that PtCAT2 confers drought stress tolerance by enhancing the H2O2 scavenging ability of plants to maintain their membrane integrity. These results improve our understanding of the drought response mechanisms and provide a potential breeding strategy for P. ternata genetic improvement.
RESUMO
Using petiole material as explants and directly inducing the formation of microtubers without going through the callus stage is an essential way to rapidly expand scarce medical plants such as Pinellia ternata. However, the early molecular mechanism underlying the formation of the microtuber is largely elusive. Here, we conducted cytology and dynamic transcriptome analyses of inchoate microtubers in Pinellia explants and identified 1092 differentially expressed genes after their cultivation in vitro for 0, 5, and 15 days. Compared with 0 day, the number and size of the microtuber cells were larger at 5 and 15 days of culture. Detailed categorization revealed that the differentially expressed genes were mainly related to responses to stimulus, biological regulation, organelles, membranes, transcription factor activity, and protein binding. Further analysis revealed that the microtuber at different incubation days exhibited quite a difference in both hormone signaling pathway transduction and the regulation pattern of transcription factors. Therefore, this study contributes to a better understanding of the early molecular regulation during the formation of the microtuber and provides new insights for the study of the rapid expansion of P. ternata and other medical plants.
Assuntos
Pinellia , Pinellia/genética , Perfilação da Expressão Gênica , Hormônios/metabolismo , Expressão GênicaRESUMO
For this state-of-science overview of geospatial approaches for identifying US communities with high lead-exposure risk, we compiled and summarized public data and national maps of lead indices and models, environmental lead indicators, and children's blood lead surveillance data. Currently available indices and models are primarily constructed from housing-age and sociodemographic data; differing methods, variables, data, weighting schemes, and geographic scales yield maps with different exposure risk profiles. Environmental lead indicators are available (e.g., air, drinking water, dust, soil) at different spatial scales, but key gaps remain. Blood lead level data have limitations as testing, reporting, and completeness vary across states. Mapping tools and approaches developed by federal agencies and other groups for different purposes present an opportunity for greater collaboration. Maps, data visualization tools, and analyses that synthesize available geospatial efforts can be evaluated and improved with local knowledge and blood lead data to refine identification of high-risk locations for prioritizing prevention efforts and targeting risk-reduction strategies. Remaining challenges are discussed along with a work-in-progress systematic approach for cross-agency data integration, toward advancing "whole-of-government" public health protection from lead exposures. (Am J Public Health. 2022;112(S7):S658-S669. https://doi.org/10.2105/AJPH.2022.307051).
Assuntos
Água Potável , Chumbo , Criança , Poeira , Exposição Ambiental/prevenção & controle , Órgãos Governamentais , Humanos , SoloRESUMO
BACKGROUND: Despite great progress in reducing environmental lead (Pb) levels, many children in the United States are still being exposed. OBJECTIVE: Our aim was to develop a generalizable approach for systematically identifying, verifying, and analyzing locations with high prevalence of children's elevated blood Pb levels (EBLLs) and to assess available Pb models/indices as surrogates, using a Michigan case study. METHODS: We obtained â¼1.9 million BLL test results of children <6 years of age in Michigan from 2006-2016; we then evaluated them for data representativeness by comparing two percentage EBLL (%EBLL) rates (number of children tested with EBLL divided by both number of children tested and total population). We analyzed %EBLLs across census tracts over three time periods and between two EBLL reference values (≥5 vs. ≥10µg/dL) to evaluate consistency. Locations with high %EBLLs were identified by a top 20 percentile method and a Getis-Ord Gi* geospatial cluster "hotspot" analysis. For the locations identified, we analyzed convergences with three available Pb exposure models/indices based on old housing and sociodemographics. RESULTS: Analyses of 2014-2016 %EBLL data identified 11 Michigan locations via cluster analysis and 80 additional locations via the top 20 percentile method and their associated census tracts. Data representativeness and consistency were supported by a 0.93 correlation coefficient between the two EBLL rates over 11 y, and a Kappa score of â¼0.8 of %EBLL hotspots across the time periods (2014-2016) and reference values. Many EBLL hotspot locations converge with current Pb exposure models/indices; others diverge, suggesting additional Pb sources for targeted interventions. DISCUSSION: This analysis confirmed known Pb hotspot locations and revealed new ones at a finer geographic resolution than previously available, using advanced geospatial statistical methods and mapping/visualization. It also assessed the utility of surrogates in the absence of blood Pb data. This approach could be applied to other states to inform Pb mitigation and prevention efforts. https://doi.org/10.1289/EHP9705.
Assuntos
Intoxicação por Chumbo , Chumbo , Setor Censitário , Criança , Exposição Ambiental , Habitação , Humanos , Intoxicação por Chumbo/epidemiologia , Michigan/epidemiologia , Estados UnidosRESUMO
The tourist experience is a core indicator of destination management for the comprehensive evaluation of destination value. Tourist experience and tourist inspiration are important concepts in the stream of research on destination marketing and management. However, these relationships remained under-explored in the extant literature. This study examined the impact of tourist experience on tourist inspiration under the moderating impact of destination familiarity. To achieve the objective of this study, data were collected online from 622 Chinese tourists. We employed partial least squares structural equation modeling (PLS-SEM) to statistically analyze the gathered data. Findings show that four types of tourist experiences, namely education, esthetics, entertainment, and escapism, significantly and positively influenced the inspired-by state of tourist inspiration, which further influenced the inspired-to-state of tourist inspiration. Destination familiarity exerted a significantly negative moderating impact on the relationship between education experience and inspired-by state of tourist inspiration. Sensitivity analysis presents that education experience was the strongest predictor of the inspired-by state followed by aesthetics, escapism, and entertainment facets of the tourist experience. Findings contribute to the theory and practice of tourism management with a robust interpretation of tourist experience, tourist inspiration, and destination familiarity to solidify the effective management of tourist destinations. Limitations and future research directions are noted.
RESUMO
Andrographis Herba, the aerial part of Andrographis paniculata (Burm. f.) Wall. ex Nees (Acanthaceae), has a wide geographic distribution and has been used for the treatment of fever, cold, inflammation, and other infectious diseases. In markets, sellers and buyers commonly inadvertently confuse with related species. In addition, most Chinese medicinal herbs are subjected to traditional processing procedures, such as steaming and boiling, before they are sold at dispensaries; therefore, it is very difficult to identify Andrographis Herba when it is processed into Chinese medicines. The identification of species and processed medicinal materials is a growing issue in the marketplace. However, conventional methods of identification have limitations, while DNA barcoding has received considerable attention as a new potential means to identify species and processed medicinal materials. In this study, 17 standard reference materials of A. paniculata, 2 standard decoctions, 27 commercial products and two adulterants were collected. Based on the ITS2 sequence, it could successfully identify A. paniculata and adulterants. Moreover, a nucleotide signature consisting of 71 bp was designed, this sequence is highly conserved and specific within A. paniculata while divergent among other species. Then, we used these new primers to amplify the nucleotide signature region from processed materials. In conclusion, the DNA barcoding method developed in the present study for authenticating A. paniculata is rapid and cost-effective. It can be used in the future to guarantee the quality of Andrographis Herba of each regulatory link for clinical use.
Assuntos
Andrographis , Medicamentos de Ervas Chinesas , Andrographis paniculata , Primers do DNARESUMO
High temperature is one of the main abiotic factors limiting agricultural production, particularly for heat-sensitive plant species. Small heat-shock proteins contribute substantially to alleviating damage to plants caused by heat stress. In the present study, the heat shock protein gene PtsHSP17.2 from Pinellia ternata was functionally characterized through promoter analysis and its overexpression in tobacco. Respectively, relative expression using real-time RT-PCR and ex situ promoter activity assay indicated that PtsHSP17.2 is strongly inducible under heat stress, and in silico promoter analysis discovered multiple stress-related cis elements including heat shock element. When overexpressing PtsHSP17.2 in tobacco, the thermotolerance of transgenic plants was markedly enhanced. Furthermore, the transgenic tobacco plants exhibited less variation in chlorophyll content, relative electrolyte leakage, and malondialdehyde content under heat stress compared with wild-type (WT) plants. The activities of antioxidant enzymes and content of proline were significantly enhanced under heat stress in transgenic plants relative to WT plants. Transgenic plants also had enhanced water retention and increased antioxidative capacity. Further, the expression levels of genes encoding antioxidant enzymes were more highly induced by heat stress in transgenic lines than WT. These results enrich the current understanding of thermal adaptation of heat-sensitive plant species and encourage further genetic improvement.
Assuntos
Proteínas de Choque Térmico Pequenas , Pinellia , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico Pequenas/genética , Proteínas de Choque Térmico Pequenas/metabolismo , Pinellia/genética , Pinellia/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Nicotiana/genética , Nicotiana/metabolismoRESUMO
Exposure to light induces tuber greening and the accumulation of the toxic alkaloid Solanine in potato (Solanum tuberosum L) during storage greatly reduce tuber value. While the mechanism of this greening process remains unclear, it is well understood that DNA methylation plays an important role in regulating gene expression in response to environmental conditions. In this study, methylation-sensitive amplified polymorphism was used to assess the effect of light exposure on DNA methylation during storage of potato tubers. Light-induced genome-wide DNA demethylation and the rate of DNA methylation decreased with long storage times. Following, the sequencing of 14 differentially amplified fragments and analysis using the Basic Local Alignment Search Tool, eight genomic sequences and six annotated fragment sequences were identified. The latter included ADP glucose pyrophosphorylase 1/2, chlorophyllide a oxygenase 1 (CAO1), receptor-like protein kinase HAIKU2, and repressor of GA4, all of which are involved in starch biosynthesis, chlorophyll synthesis, endosperm development, and gibberellic acid signaling, respectively. Demethylation was observed in the CpG island (-273 to -166 bp) of the CAO1 promoter in response to light, which further confirmed that the variations in genome methylation are dependent upon the light exposure and suggests a direct role for DNA methylation. Our results provide an epigenetic perspective for further exploring the mechanism of light-induced tuber greening.
Assuntos
Solanum tuberosum , Metabolismo dos Carboidratos , Metilação de DNA , Glucose-1-Fosfato Adenililtransferase , Tubérculos/genética , Solanum tuberosum/genéticaRESUMO
Purpose: To investigate the therapeutic effects of minocycline combined with tinidazole in the treatment of chronic periodontitis (CP). Methods: Seventy-three CP patients treated May 2018December 2019 at Yuyao People's Hospital (Yuyao, China) were enrolled in this study: 34 were treated with minocycline alone (control group; CG) and 39 were treated with a combination of minocycline and tinidazole (observation group; OG). Both groups were treated continuously for four weeks and plaque index (PLI), bleeding index (BI), periodontal pocket depth (PD), periodontal attachment level (PAL) and alveolar bone height were compared before and after treatment. Pain was evaluated using the visual analogue scale (VAS). Levels of TNF-α and IL-6 before and after treatment were determined using an enzyme-linked immunosorbent assay. Adverse reactions were compared. Results: In each group, PLI, BI, PD, PAL and alveolar bone height were lower after treatment (P<0.05), and those in OG were lower than those in CG (P<0.05). TNF-α and IL-6 levels in both groups were lower after treatment (P<0.05), and the levels in serum of the OG were lower than those of the CG (P<0.05). After treatment, the VAS in OG was lower than that of CG (P<0.05). There was no significant difference in adverse reactions between groups (P>0.05). Conclusion: Minocycline combined with tinidazole was more effective in treating CP than minocycline alone. This drug combination improved the periodontal indexes and inflammatory reaction of CP and relieved their pain. No significant difference in adverse reactions was seen.
Assuntos
Periodontite Crônica , Minociclina , Antibacterianos/uso terapêutico , Periodontite Crônica/tratamento farmacológico , Humanos , Minociclina/uso terapêutico , Tinidazol/uso terapêuticoRESUMO
Phytohormones play an important role at all stages of plant growth, influencing plant growth and development and regulating plant secondary metabolism, such as the synthesis of flavone, flavonol, anthocyanin, and other flavonoids. Flavonoids, a group of important secondary metabolites ubiquitous in plants, have antioxidative, anti-microbial, and anti-inflammatory activities and thus have a wide range of potential applications in Chinese medicine and food nutrition. With the development of biotechnology, phytohormones' regulation on flavonoids has become a research focus in recent years. This study reviewed the research progress on the mechanism of common phytohormones, such as abscisic acid, gibberellin, methyl jasmonate, and salicylic acid, in regulating flavonoid metabolism, and discussed the molecular mechanism of the synthesis and accumulation of flavonoids, aiming at clarifying the key role of phytohormones in modulating flavonoid metabolism. The result is of guiding significance for improving the content of flavonoids in plants through rational use of phytohormones and of reference value for exploring the mechanism of hormones in regulating flavonoid metabolism.
Assuntos
Giberelinas , Reguladores de Crescimento de Plantas , Ácido Abscísico , Flavonoides , Regulação da Expressão Gênica de Plantas , Desenvolvimento VegetalRESUMO
Pinellia ternata is a native herb in China, and its tuber is widely-used in traditional Chinese medicines. It has been identified that the shading treatment promotes tuber production during cultivation. However, the tuber quality in shaded environments is unknown, which limits the scientific cultivation of P. ternata. In this study, a metabolomics approach based on UHPLC-MS was applied to assess the metabolic components of P. ternata in response to shading. Diverse metabolites were profiled using the metabolomics approach. Then, datasets of P. ternata cultivated in natural light (control) and shaded environments were subjected to multivariate analyses. Two P. ternata tuber products were well separated by the PCA. In total, four P. ternata alkaloids with contents that were not altered by the shaded environment were detected. Metabolomic analyses further identified several organic acids [mevalonic acid, 12,13-dihydroxy-9Z-octadecenoic acid (12, 13-DiHOME), urocanic acid, and γ-aminobutyric acid] that were largely enriched in the shaded environment, which likely contributed to tuber quality and growth. This study determined that shading probably improves the quality of P. ternata tubers and laid a foundation for exploring the regulatory mechanism of the shade response in P. ternata.