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1.
J Virol ; 98(7): e0033424, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38829137

RESUMEN

Porcine deltacoronavirus (PDCoV) is an enteric pathogenic coronavirus that causes acute and severe watery diarrhea in piglets and has the ability of cross-species transmission, posing a great threat to swine production and public health. The interferon (IFN)-mediated signal transduction represents an important component of virus-host interactions and plays an essential role in regulating viral infection. Previous studies have suggested that multifunctional viral proteins encoded by coronaviruses antagonize the production of IFN via various means. However, the function of these viral proteins in regulating IFN-mediated signaling pathways is largely unknown. In this study, we demonstrated that PDCoV and its encoded nucleocapsid (N) protein antagonize type I IFN-mediated JAK-STAT signaling pathway. We identified that PDCoV infection stimulated but delayed the production of IFN-stimulated genes (ISGs). In addition, PDCoV inhibited JAK-STAT signal transduction by targeting the nuclear translocation of STAT1 and ISGF3 formation. Further evidence showed that PDCoV N is the essential protein involved in the inhibition of type I IFN signaling by targeting STAT1 nuclear translocation via its C-terminal domain. Mechanistically, PDCoV N targets STAT1 by interacting with it and subsequently inhibiting its nuclear translocation. Furthermore, PDCoV N inhibits STAT1 nuclear translocation by specifically targeting KPNA2 degradation through the lysosomal pathway, thereby inhibiting the activation of downstream sensors in the JAK-STAT signaling pathway. Taken together, our results reveal a novel mechanism by which PDCoV N interferes with the host antiviral response.IMPORTANCEPorcine deltacoronavirus (PDCoV) is a novel enteropathogenic coronavirus that receives increased attention and seriously threatens the pig industry and public health. Understanding the underlying mechanism of PDCoV evading the host defense during infection is essential for developing targeted drugs and effective vaccines against PDCoV. This study demonstrated that PDCoV and its encoded nucleocapsid (N) protein antagonize type I interferon signaling by targeting STAT1, which is a crucial signal sensor in the JAK-STAT signaling pathway. Further experiments suggested that PDCoV N-mediated inhibition of the STAT1 nuclear translocation involves the degradation of KPNA2, and the lysosome plays a role in KPNA2 degradation. This study provides new insights into the regulation of PDCoV N in the JAK-STAT signaling pathway and reveals a novel mechanism by which PDCoV evades the host antiviral response. The novel findings may guide us to discover new therapeutic targets and develop live attenuated vaccines for PDCoV infection.


Asunto(s)
Deltacoronavirus , Proteínas de la Nucleocápside , Factor de Transcripción STAT1 , Transducción de Señal , Animales , Porcinos , Factor de Transcripción STAT1/metabolismo , Deltacoronavirus/metabolismo , Proteínas de la Nucleocápside/metabolismo , Humanos , Quinasas Janus/metabolismo , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/metabolismo , alfa Carioferinas/metabolismo , Interferón Tipo I/metabolismo , Infecciones por Coronavirus/virología , Infecciones por Coronavirus/metabolismo , Células HEK293 , Línea Celular , Proteolisis , Interacciones Huésped-Patógeno
2.
Langmuir ; 40(9): 4623-4634, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38300846

RESUMEN

While the simplest outcome of a normal impact on a flat stationary solid surface is radially symmetric spreading, it is important to note that asymmetric spreading can intrinsically occur with a tangential velocity along the surface. However, no previous attempt has been made to restore the symmetry of a lamella that intrinsically spreads asymmetrically. Adjusting the lamella's asymmetric shape to a symmetric one is achieved in this work by varying wettability to affect the receding velocity of the contact line, according to the Taylor-Culick theory. Here we theoretically and practically show how restoring the symmetry can be achieved. Theoretically we built a framework to map the needed receding velocity at every given point of the contact line to allow for symmetry to be restored, and then this framework was applied to generate a wetting map that shows how at each local the wettability of the surface needs to be defined. Simulated results confirmed the effectiveness of our framework and identified the envelope of its applicability. Next, to apply the idea experimentally, the wetting map was transformed to a single wettability contrast area dubbed the "patch". Experimental results showed the effectiveness of the patch design in correcting the asymmetric spreading lamella for water droplets impacting a surface for the following Weber number conditions: Wen ≤ 300, Wet ≤ 300, and 0.51 ≤ Wen/Wet ≤ 2.04.

3.
J Nat Prod ; 87(9): 2160-2169, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39190018

RESUMEN

Notoginsenosides are important bioactive compounds from Panax notoginseng (Burk.) F. H. Chen, most of which have xylose in their sugar chains. However, the xylosyltransferases involved in the generation of notoginsenosides remain poorly understood, posing a bottleneck for further study of the biosynthesis of notoginsenosides. In this work, a new xylosyltransferase gene, PnUGT57 (named UGT94BW1), was identified from P. notoginseng, which has a distinct sequence and could catalyze the 2'-O glycosylation of ginsenosides Rh1 and Rg1 to produce notoginsenosides R2 and R1, respectively. We first characterized the optimal conditions for the PnUGT57 activity and its enzymatic kinetic parameters, and then, molecular docking and site-directed mutagenesis were performed to elucidate the catalytic mechanism of PnUGT57. Combined with the results of site-directed mutagenesis, Glu26, Ser266, Glu267, Trp347, Ser348, and Glu352 in PnUGT57 were identified as the key residues involved in 2'-O glycosylation of C-6 O-Glc, and PnUGT57R175A and PnUGT57G237A could significantly improve the catalytic activity of PnUGT57. These findings not only provide a new xylosyltransferase gene for augmenting the plant xylosyltransferase database but also identify the pivotal sites and catalytic mechanism of the enzyme, which would provide reference for the modification and application of xylosyltransferases in the future.


Asunto(s)
Ginsenósidos , Panax notoginseng , Pentosiltransferasa , UDP Xilosa Proteína Xilosiltransferasa , Ginsenósidos/metabolismo , Ginsenósidos/biosíntesis , Ginsenósidos/química , Glicosilación , Pentosiltransferasa/metabolismo , Pentosiltransferasa/genética , Estructura Molecular , Mutagénesis Sitio-Dirigida , Simulación del Acoplamiento Molecular
4.
J Sci Food Agric ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39118479

RESUMEN

BACKGROUND: Sanqi, the root of Panax notoginseng, has long been recognized for its therapeutic effects on cardiovascular diseases. Saponins, including ginsenosides and notoginsenosides, are the main bioactive components of P. notoginseng. The biosynthesis of saponins is closely related to the defense responses orchestrated by endogenous hormones. RESULTS: To provide new insights into the underlying role of phytohormone jasmonic acid (JA) in the synthesis and regulation of saponins, we performed an ultra-performance liquid chromatography analysis of different tissues of P. notoginseng aged 2-4 years. Moreover, by combined evaluation of saponin content and transcriptome profiling of each tissue, the spatial and temporal distribution of saponins was analyzed. N notoginsenoside R1, ginsenoside Rb1 and ginsenoside Rd accumulated in the underground tissues, including the root, tuqi, fibril and rhizome. In agreement with this data, the corresponding genes of the endogenous hormone JAs, especially coronatine insensitive 1 (COI1) and myelocytomatosis proteins 2 (MYC2), were predominantly expressed in the underground tissues. The tissue- and age-specific distribution of saponins was consistent with the expression of genes involved in JA biosynthetic, metabolic and signaling pathways. CONCLUSION: The present study has revealed the temporal and spatial effects of endogenous phtohormones in the synthesis and regulation of notoginsenosides, which will provide a significant impact on improving the ecological planting technology, cultivating new high-quality varieties and protecting the rare resources of medicinal P. notoginseng. © 2024 Society of Chemical Industry.

5.
Angew Chem Int Ed Engl ; 63(44): e202410356, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39107253

RESUMEN

Electrocatalytic nitrate (NO3 -) reduction to ammonia (NRA) offers a promising pathway for ammonia synthesis. The interfacial electronic interactions (IEIs) can regulate the physicochemical capabilities of catalysts in electrochemical applications, while the impact of IEIs on electrocatalytic NRA remains largely unexplored in current literature. In this study, the high-efficiency electrode Ag-modified Co3O4 (Ag1.5Co/CC) is prepared for NRA in neutral media, exhibiting an impressive nitrate conversion rate of 96.86 %, ammonia Faradaic efficiency of 96.11 %, and ammonia selectivity of ~100 %. Notably, the intrinsic activity of Ag1.5Co/CC is ~81 times that of Ag nanoparticles (Ag/CC). Multiple characterizations and theoretical computations confirm the presence of IEIs between Ag and Co3O4, which stabilize the CoO6 octahedrons within Co3O4 and significantly promote the adsorption of reactants (NO3 -) as well as intermediates (NO2 - and NO), while suppressing the Heyrovsky step, thereby improving nitrate electroreduction efficiency. Furthermore, our findings reveal a synergistic effect between different active sites that enables tandem catalysis for NRA: NO3 - reduction to NO2 - predominantly occurs at Ag sites while NO2 - tends to hydrogenate to ammonia at Co sites. This study offers valuable insights for the development of high-performance NRA electrocatalysts.

6.
Proc Natl Acad Sci U S A ; 117(37): 22974-22983, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32873649

RESUMEN

Medium-chain fatty alcohols (MCFOHs, C6 to C12) are potential substitutes for fossil fuels, such as diesel and jet fuels, and have wide applications in various manufacturing processes. While today MCFOHs are mainly sourced from petrochemicals or plant oils, microbial biosynthesis represents a scalable, reliable, and sustainable alternative. Here, we aim to establish a Saccharomyces cerevisiae platform capable of selectively producing MCFOHs. This was enabled by tailoring the properties of a bacterial carboxylic acid reductase from Mycobacterium marinum (MmCAR). Extensive protein engineering, including directed evolution, structure-guided semirational design, and rational design, was implemented. MmCAR variants with enhanced activity were identified using a growth-coupled high-throughput screening assay relying on the detoxification of the enzyme's substrate, medium-chain fatty acids (MCFAs). Detailed characterization demonstrated that both the specificity and catalytic activity of MmCAR was successfully improved and a yeast strain harboring the best MmCAR variant generated 2.8-fold more MCFOHs than the strain expressing the unmodified enzyme. Through deletion of the native MCFA exporter gene TPO1, MCFOH production was further improved, resulting in a titer of 252 mg/L for the final strain, which represents a significant improvement in MCFOH production in minimal medium by S. cerevisiae.


Asunto(s)
Alcoholes Grasos/metabolismo , Oxidorreductasas/metabolismo , Antiportadores/metabolismo , Biocombustibles , Ácidos Grasos/metabolismo , Ingeniería Metabólica/métodos , Proteínas de Transporte de Catión Orgánico/genética , Oxidorreductasas/fisiología , Ingeniería de Proteínas/métodos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
7.
Sensors (Basel) ; 22(16)2022 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-36015825

RESUMEN

Mildew of maize seeds may affect their germination rates and reduce crop quality. It is crucial to classify maize seeds efficiently and without destroying their original structure. This study aimed to establish hyperspectral datasets using hyperspectral imaging (HSI) of maize seeds with different degrees of mildew and then classify them using spectral characteristics and machine learning algorithms. Initially, the images were processed with Otus and morphological operations. Each seed's spectral features were extracted based on its coding, its edge, region of interest (ROI), and original pixel coding. Random forest (RF) models were optimized using the sparrow search algorithm (SSA), which is incapable of escaping the local optimum; hence, it was optimized using a modified reverse sparrow search algorithm (JYSSA) strategy. This reverse strategy selects the top 10% as the elite group, allowing us to escape from local optima while simultaneously expanding the range of the sparrow search algorithm's optimal solution. Finally, the JYSSA-RF algorithm was applied to the validation set, with 96% classification accuracy, 100% precision, and a 93% recall rate. This study provides novel ideas for future nondestructive detection of seeds and moldy seed selection by combining hyperspectral imaging and JYSSA algorithms based on optimized RF.


Asunto(s)
Imágenes Hiperespectrales , Zea mays , Algoritmos , Hongos , Aprendizaje Automático , Semillas/química , Máquina de Vectores de Soporte , Zea mays/química
8.
Int Heart J ; 63(3): 612-622, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35650161

RESUMEN

Acoustic cardiography (AC) combined with heart sound (HS) recording and electrocardiogram (ECG) provides a noninvasive and inexpensive way to understand the electrical mechanical activity of the heart. Pulmonary artery stenosis can cause hemodynamic abnormalities that might lead to pulmonary hypertension (PH). In this paper, we examined the relationships between the acoustic characteristics of the AC and hemodynamic changes in a beagle dog model of PH.Four healthy beagle dogs were injected with the prostaglandin endoperoxide receptor agonist U-44069 to induce acute PH states. AC was employed to analyze the process of pre-PH, intra-PH, and post-PH. Right ventricular blood pressure (RVBP) was measured via right cardiac catheterization, an invasive method performed in parallel for comparative hemodynamic evaluation. As RVBP increased or decreased, the HS features changed accordingly during acute PH occurrence and development. Right ventricular systolic blood pressure (RVSBP) significantly correlated with the minimum of the first HS (S1) amplitude (correlation coefficient (CC) = -0.82), energy of the S1 (CC = 0.86), energy of the second HS (S2) (CC = 0.67), entropy of the S1 (CC = -0.94), and ratio of electromechanical systolic time (EMST) to the cardiac cycle time (CC = 0.81). The two techniques (AC [HSs and ECG] versus right cardiac catheterization [RVBP]) were significantly correlated. Especially, the diastolic filling time (DFT) had a significant relationship with the right ventricular diastolic time (RVDT) (CC = 0.97), perfusion time (PT) (CC = 0.96), and cardiac cycle time (RR) (CC = 0.96). The CCs between the RVDT and the max dp/dt to min dp/dt, the EMST and the Q to min dp/dt, and the electromechanical activation time and the Q to max dp/dt were 0.95, 0.99, and 0.86, respectively. Furthermore, the logistic regression model with different combinations was used to identify the effective features for monitoring hemodynamic and pathophysiologic conditions.AC provided significant insight into mechanical dysfunction in a rapid and noninvasive way that could be used for early screening of PH.


Asunto(s)
Hipertensión Pulmonar , Animales , Cateterismo Cardíaco , Diástole , Perros , Corazón , Hemodinámica , Humanos , Hipertensión Pulmonar/diagnóstico
9.
New Phytol ; 227(3): 930-943, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32187685

RESUMEN

Lonicera japonica is a widespread member of the Caprifoliaceae (honeysuckle) family utilized in traditional medical practices. This twining vine honeysuckle also is a much-sought ornamental, in part due to its dynamic flower coloration, which changes from white to gold during development. The molecular mechanism underlying dynamic flower coloration in L. japonica was elucidated by integrating whole genome sequencing, transcriptomic analysis and biochemical assays. Here, we report a chromosome-level genome assembly of L. japonica, comprising nine pseudochromosomes with a total size of 843.2 Mb. We also provide evidence for a whole-genome duplication event in the lineage leading to L. japonica, which occurred after its divergence from Dipsacales and Asterales. Moreover, gene expression analysis not only revealed correlated expression of the relevant biosynthetic genes with carotenoid accumulation, but also suggested a role for carotenoid degradation in L. japonica's dynamic flower coloration. The variation of flower color is consistent with not only the observed carotenoid accumulation pattern, but also with the release of volatile apocarotenoids that presumably serve as pollinator attractants. Beyond novel insights into the evolution and dynamics of flower coloration, the high-quality L. japonica genome sequence also provides a foundation for molecular breeding to improve desired characteristics.


Asunto(s)
Lonicera , Carotenoides , Flores/genética , Perfilación de la Expresión Génica , Lonicera/genética
10.
Biochem Biophys Res Commun ; 516(2): 515-520, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31230744

RESUMEN

Glioma is the most common primary brain tumor with high mortality. Given the poor outcomes with standard-of-care treatments, novel treatment strategies are needed. Oncolytic viral therapy for glioma has developed as an exciting therapeutic method in recent years. Zika virus, a member of flavivirus family, has oncolytic activity against glioma cells but the mechanism is unknown. Here, we aimed to determine which viral protein might play a critical role in mitigating glioma cell growth. We examined the tumor suppressor function of four nonstructural proteins NS1, NS3, NS4B and NS5 in human glioma cell line U87. As a result, we found that only NS5 significantly inhibited proliferation, migration and invasion of U87 cells. Moreover, expression of NS5 suppressed tumorigenicity of mouse GL261 glioma cell in vivo. Our findings provide some clues for further exploration of oncolytic Zika virus in the treatment of glioma.


Asunto(s)
Glioma/patología , Proteínas no Estructurales Virales/farmacología , Virus Zika/metabolismo , Animales , Carcinogénesis/efectos de los fármacos , Carcinogénesis/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células HEK293 , Humanos , Masculino , Ratones Endogámicos C57BL , Invasividad Neoplásica , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/patología
11.
Small ; 15(21): e1900131, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31018041

RESUMEN

Transition metal dichalcogenides exhibit several different phases (e.g., semiconducting 2H, metallic 1T, 1T') arising from the collective and sluggish atomic displacements rooted in the charge-lattice interaction. The coexistence of multiphase in a single sheet enables ubiquitous heterophase and inhomogeneous charge distribution. Herein, by combining the first-principles calculations and experimental investigations, a strong charge transfer ability at the heterophase boundary of molybdenum disulfide (MoS2 ) assembled together with graphene is reported. By modulating the phase composition in MoS2 , the performance of the nanohybrid for energy storage can be modulated, whereby remarkable gravimetric and volumetric capacitances of 272 F g-1 and 685 F cm-3 are demonstrated. As a proof of concept for energy application, a flexible solid-state asymmetric supercapacitor is constructed with the MoS2 -graphene heterolayers, which shows superb energy and power densities (46.3 mWh cm-3 and 3.013 W cm-3 , respectively). The present work demonstrates a new pathway for efficient charge flow and application in energy storage by engineering the phase boundary and interface in 2D materials of transition metal dichalcogenides.

12.
Small ; 14(43): e1702641, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29076649

RESUMEN

Direct assembling of active materials on carbon cloth (CC) is a promising way to achieve flexible electrodes for energy storage. However, the overall surface area and electrical conductivity of such electrodes are usually limited. Herein, 2D metal-organic framework derived nanocarbon nanowall (MOFC) arrays are successfully developed on carbon cloth by a facile solution + carbonization process. Upon growth of the MOFC arrays, the sites for growth of the active materials are greatly increased, and the equivalent series resistance is decreased, which contribute to the enhancement of the bare CC substrate. After decorating ultrathin flakes of MnO2 and Bi2 O3 on the flexible CC/MOFC substrate, the hierarchical electrode materials show an abrupt improvement of areal capacitances by around 50% and 100%, respectively, compared to those of the active materials on pristine carbon cloth. A flexible supercapacitor can be further assembled using two hierarchical electrodes, which demonstrates an energy density of 124.8 µWh cm-2 at the power density of 2.55 mW cm-2 .

13.
Metab Eng ; 45: 51-58, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29183749

RESUMEN

The yeast Saccharomyces cerevisiae is an attractive host for industrial scale production of biofuels including fatty alcohols due to its robustness and tolerance towards harsh fermentation conditions. Many metabolic engineering strategies have been applied to generate high fatty alcohol production strains. However, impaired growth caused by fatty alcohol accumulation and high cost of extraction are factors limiting large-scale production. Here, we demonstrate that the use of heterologous transporters is a promising strategy to increase fatty alcohol production. Among several plant and mammalian transporters tested, human FATP1 was shown to mediate fatty alcohol export in a high fatty alcohol production yeast strain. An approximately five-fold increase of fatty alcohol secretion was achieved. The results indicate that the overall cell fitness benefited from fatty alcohol secretion and that the acyl-CoA synthase activity of FATP1 contributed to increased cell growth as well. This is the first study that enabled an increased cell fitness for fatty alcohol production by heterologous transporter expression in yeast, and this investigation indicates a new potential function of FATP1, which has been known as a free fatty acid importer to date. We furthermore successfully identified the functional domain of FATP1 involved in fatty alcohol export through domain exchange between FATP1 and another transporter, FATP4. This study may facilitate a successful commercialization of fatty alcohol production in yeast and inspire the design of novel cell factories.


Asunto(s)
Proteínas de Transporte de Ácidos Grasos , Alcoholes Grasos/metabolismo , Expresión Génica , Saccharomyces cerevisiae , Proteínas de Transporte de Ácidos Grasos/biosíntesis , Proteínas de Transporte de Ácidos Grasos/genética , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
15.
J Ind Microbiol Biotechnol ; 44(7): 1065-1072, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28547322

RESUMEN

Beta-elemene, a sesquiterpene and the major component of the medicinal herb Curcuma wenyujin, has antitumor activity against various types of cancer and could potentially serve as a potent antineoplastic drug. However, its current mode of production through extraction from plants has been inefficient and suffers from limited natural resources. Here, we engineered a yeast cell factory for the sustainable production of germacrene A, which can be transformed to beta-elemene by a one-step chemical reaction in vitro. Two heterologous germacrene A synthases (GASs) converting farnesyl pyrophosphate (FPP) to germacrene A were evaluated in yeast for their ability to produce germacrene A. Thereafter, several metabolic engineering strategies were used to improve the production level. Overexpression of truncated 3-hydroxyl-3-methylglutaryl-CoA reductase and fusion of FPP synthase with GAS, led to a sixfold increase in germacrene A production in shake-flask culture. Finally, 190.7 mg/l of germacrene A was achieved. The results reported in this study represent the highest titer of germacrene A reported to date. These results provide a basis for creating an efficient route for further industrial application re-placing the traditional extraction of beta-elemene from plant sources.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Ingeniería Metabólica , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sesquiterpenos de Germacrano/biosíntesis , Sesquiterpenos/metabolismo , Técnicas de Cultivo Celular por Lotes , Medios de Cultivo/química , Geraniltranstransferasa/genética , Geraniltranstransferasa/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , Fosfatos de Poliisoprenilo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
Biotechnol Lett ; 36(2): 363-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24078134

RESUMEN

Tanshinones are a group of bioactive abietane-type norditerpenoid quinone compounds in Salvia miltiorrhiza. Copalyldiphosphate synthase of S. miltiorrhiza (SmCPS) is the first key enzyme in tanshinone biosynthesis from the universal diterpene precursor geranylgeranyl diphosphate. Hairy roots of S. miltiorrhiza were transformed with Agrobacterium rhizogenes carrying an RNA interference (RNAi) construct designed to silence SmCPS, and we examined the resulting SmCPS expression and tanshinone accumulation. In SmCPS­RNAi hairy roots, the transcript level of SmCPS was reduced to 26 % while the dihydrotanshinone I and cryptotanshinone levels were decreased by 53 and 38 % compared to those of the vector control hairy roots; tanshinone IIA was not detected. Therefore, the decreased expression of SmCPS caused a decrease in tanshinone levels which verifies that SmCPS is a key enzyme for tanshinone biosynthesis in S. miltiorrhiza.


Asunto(s)
Transferasas Alquil y Aril/biosíntesis , Diterpenos/análisis , Regulación hacia Abajo , Fenantrenos/análisis , Proteínas de Plantas/biosíntesis , Interferencia de ARN , Salvia miltiorrhiza/enzimología , Salvia miltiorrhiza/genética , Agrobacterium/genética , Transferasas Alquil y Aril/genética , Vías Biosintéticas/genética , Perfilación de la Expresión Génica , Silenciador del Gen , Proteínas de Plantas/genética , Raíces de Plantas/enzimología , Raíces de Plantas/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo
17.
Zhongguo Zhong Yao Za Zhi ; 39(21): 4174-9, 2014 Nov.
Artículo en Zh | MEDLINE | ID: mdl-25775789

RESUMEN

Based on the transcriptome database of Salvia miltiorrhiza, specific primers were designed to clone a full-length cDNA of ent-kaurene oxidase synthase (SmKOL) using the RACE strategy. ORF Finder was used to find the open reading frame of SmKOL cDNA, and ClustalW has been performed to analysis the multiple amino acid sequence alignment. Phylogenetic tree has been constructed using MEGA 5.1. The transcription level of SmKOL from the hairy roots induced by elicitor methyl jasmonate (MeJA) was qualifiedby real-time quantitative PCR. The full length of SmKOL cDNA was of 1 884 bp nucleotides encoding 519 amino acids. The molecular weight of the SmKOL protein was about 58.88 kDa with isoelectric point (pI) of 7.62. Results of real-time quantitative PCR analyses indicated that the level of SmKOL mRNA expression in hairy roots was increased by elicitor oMeJA, and reached maximum in 36 h. The full-length cDNA of SmKOL was cloned from S. miltiorrhiza hairy root, which provides a target gene for further studies of its function, gibberellin biosynthesis and regulation of secondary metabolites.


Asunto(s)
Biología Computacional/métodos , Sistema Enzimático del Citocromo P-450/genética , Salvia miltiorrhiza/enzimología , Secuencia de Aminoácidos , Clonación Molecular , Sistema Enzimático del Citocromo P-450/química , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Estructura Terciaria de Proteína
18.
Food Chem ; 460(Pt 3): 140626, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39128363

RESUMEN

Glucose-derived acids for the further production of value-added medicine, food additives, and polymers, will promote lignocellulosic biomass biorefinery industry. In response to the diversity and complexity, a new method was established by employing high performance anion exchange chromatography (HPAEC) coupled with a CarboPac™ PA200 column, for the precise and fast determination of glucose, gluconic acid, glucuronic acid, 2-ketogluconic acid, 5-ketogluconic acid and glucaric acid. Based on the analysis of tiny varieties in retention behavior, a gradient elution mode was designed and optimized for the quantitative and qualitative analysis. The protocol displayed acceptable linearity (R2 ≥ 0.995), commendable average recovery rate (95.28% âˆ¼ 99.89%), satisfactory precision (RSD% ≤ 1.5%), and sufficient resolution (R > 6). Additionally, this method was successfully applied to the high-value biorefining process, which confirmed the practicability and accuracy. The results demonstrated that HPAEC has good detection performance for glucose and its derivative acids, and provide key identification technical support for the high-value utilization of lignocellulose.


Asunto(s)
Biomasa , Glucosa , Cromatografía por Intercambio Iónico/métodos , Glucosa/análisis , Glucosa/química , Cromatografía Líquida de Alta Presión/métodos , Lignina/química , Ácidos/análisis , Ácidos/química
19.
Nanoscale ; 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39420640

RESUMEN

Bimetallic metal-organic frameworks (MOFs) have been studied extensively in various fields, including photocatalytic and electrocatalytic applications. The enhanced catalytic activity is typically attributed to the synergistic effect of the two metals, often without further explanation. Here, we demonstrate a CoNi-bimetallic triazolate MOF with fixed metal occupancy within the MOF's secondary building unit. Due to the difference in electronegativity and so on, the charge redistribution between the two metal centers could be responsible for the enhanced photocatalytic activity. In addition, the metal(II)-triazolate MOFs we synthesized exhibit unique metal-N coordination and a strong bond between the metal center and triazole ring. Therefore, their crystal structure and high porosity are highly retained even after exposure to humid environments for several months or stirring in water for several days. Overall, the CoNi-bimetallic triazolate MOF combines the excellent water stability and high surface area of its two monometallic counterparts. It can be further tailored to yield the highest colloidal stability during photocatalytic water treatment. As a result, the dual metal centers within the bimetallic MOF, combined with boosted colloidal stability, demonstrate the highest reactive oxygen species generation and promising antibacterial performance compared to their Ni- or Co-based counterparts. These findings shed light on the future design of robust MOF-based photocatalysts, particularly bimetallic ones.

20.
Cell Death Dis ; 15(2): 139, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355684

RESUMEN

Radioresistance imposes a great challenge in reducing tumor recurrence and improving the clinical prognosis of individuals having oral squamous cell carcinoma (OSCC). OSCC harbors a subpopulation of CD44(+) cells that exhibit cancer stem-like cell (CSC) characteristics are involved in malignant tumor phenotype and radioresistance. Nevertheless, the underlying molecular mechanisms in CD44( + )-OSCC remain unclear. The current investigation demonstrated that methyltransferase-like 3 (METTL3) is highly expressed in CD44(+) cells and promotes CSCs phenotype. Using RNA-sequencing analysis, we further showed that Spalt-like transcription factor 4 (SALL4) is involved in the maintenance of CSCs properties. Furthermore, the overexpression of SALL4 in CD44( + )-OSCC cells caused radioresistance in vitro and in vivo. In contrast, silencing SALL4 sensitized OSCC cells to radiation therapy (RT). Mechanistically, we illustrated that SALL4 is a direct downstream transcriptional regulation target of METTL3, the transcription activation of SALL4 promotes the nuclear transport of ß-catenin and the expression of downstream target genes after radiation therapy, there by activates the Wnt/ß-catenin pathway, effectively enhancing the CSCs phenotype and causing radioresistance. Herein, this study indicates that the METTL3/SALL4 axis promotes the CSCs phenotype and resistance to radiation in OSCC via the Wnt/ß-catenin signaling pathway, and provides a potential therapeutic target to eliminate radioresistant OSCC.


Asunto(s)
Adenina/análogos & derivados , Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Neoplasias de la Boca/genética , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Línea Celular Tumoral , Recurrencia Local de Neoplasia/patología , Neoplasias de Cabeza y Cuello/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , Proliferación Celular/genética , Células Madre Neoplásicas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
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