RESUMEN

Leech infestation poses a significant threat to Mithun (Bos frontalis) in the north-eastern region of India, leading to various health issues and potential fatality. To address this pressing concern, we conducted a comprehensive research study aimed at assessing the efficacy of herbal plant extracts against aquatic leeches, particularly Tyrannobdella rex, and land leeches of the Philobdella sp. Our investigation involved the evaluation of six distinct plant extracts, with a focus on their ability to combat leech infestation. The results of our study revealed that among the various plant extracts tested, only the ethanolic extracts of soapnut (Sapindus mukorossi) and tobacco (Nicotiana tabacum) exhibited notable effectiveness in combating aquatic leeches. At a concentration of 5%, these extracts displayed significant lethality, with soapnut extract achieving a remarkable kill time of 6.0 ± 0.40 min, while tobacco extract showed a kill time of 31.5 ± 1.32 min. In the case of land leeches, tobacco extract proved to be highly efficient, with an average kill time of 1.5 ± 0.28 min at a 5% concentration. Soapnut extract also exhibited effectiveness against land leeches, albeit with a slightly longer kill time of 14.25 ± 1.10 min at the same concentration. Additionally, Litsea grass oil (Litsea cubeba) demonstrated promising efficacy against both aquatic and land leeches, suggesting its potential as a versatile leech control agent. These compelling findings have significant implications for the management and control of leech infestation among Mithun populations. By identifying and harnessing the leech-repelling properties of soapnut, tobacco, and Litsea grass oil, this research offers practical and environmentally friendly solutions for mitigating the adverse effects of leech infestation. Furthermore, the insights gained from this study pave the way for the development of innovative strategies to safeguard the health and well-being of Mithun in the future.

Asunto(s)

Sanguijuelas , Extractos Vegetales , Animales , Extractos Vegetales/farmacología , Sanguijuelas/efectos de los fármacos , India , Nicotiana/química , Infestaciones Ectoparasitarias/parasitología , Infestaciones Ectoparasitarias/tratamiento farmacológico , Infestaciones Ectoparasitarias/veterinaria , Etanol

RESUMEN

The MD-2-related lipid-recognition (ML/Md-2) domain is a lipid/sterol-binding domain that are involved in sterol transfer and innate immunity in eukaryotes. Here we report a genome-wide survey of this family, identifying 84 genes in 30 fungi including plant pathogens. All the studied species were found to have varied ML numbers, and expansion of the family was observed in Rhizophagus irregularis (RI) with 33 genes. The molecular docking studies of these proteins with cholesterol derivatives indicate lipid-binding functional conservation across the animal and fungi kingdom. The phylogenetic studies among eukaryotic ML proteins showed that Puccinia ML members are more closely associated with animal (insect) npc2 proteins than other fungal ML members. One of the candidates from leaf rust fungus Puccinia triticina, Pt5643 was PCR amplified and further characterized using various studies such as qRT-PCR, subcellular localization studies, yeast functional complementation, signal peptide validation, and expression studies. The Pt5643 exhibits the highest expression on the 5th day post-infection (dpi). The confocal microscopy of Pt5643 in onion epidermal cells and N. benthamiana shows its location in the cytoplasm and nucleus. The functional complementation studies of Pt5643 in npc2 mutant yeast showed its functional similarity to the eukaryotic/yeast npc2 gene. Furthermore, the overexpression of Pt5643 also suppressed the BAX, NEP1, and H2O2-induced program cell death in Nicotiana species and yeast. Altogether the present study reports the novel function of ML domain proteins in plant fungal pathogens and their possible role as effector molecules in host defense manipulation.

Asunto(s)

Muerte Celular , Proteínas Fúngicas , Filogenia , Enfermedades de las Plantas , Enfermedades de las Plantas/microbiología , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Nicotiana/microbiología , Nicotiana/metabolismo , Nicotiana/genética , Basidiomycota/patogenicidad , Basidiomycota/metabolismo , Basidiomycota/genética , Puccinia/patogenicidad , Puccinia/metabolismo , Dominios Proteicos , Simulación del Acoplamiento Molecular , Cebollas/microbiología , Cebollas/metabolismo , Cebollas/genética

RESUMEN

Cigarette smoke, a complex mixture produced by tobacco combustion, contains a variety of carcinogens and can trigger DNA damage. Overactivation of c-MET, a receptor tyrosine kinase, may cause cancer and cellular DNA damage, but the underlying mechanisms are unknown. In this work, we investigated the mechanisms of cigarette smoke extract (CSE) induced malignant transformation and DNA damage in human bronchial epithelial cells (BEAS-2B). The results demonstrated that CSE treatment led to up-regulated mRNA expression of genes associated with the c-MET signaling pathway, increased expression of the DNA damage sensor protein γ-H2AX, and uncontrolled proliferation in BEAS-2B cells. ATR, ATR, and CHK2, which are involved in DNA damage repair, as well as the phosphorylation of c-MET and a group of kinases (ATM, ATR, CHK1, CHK2) involved in the DNA damage response were all activated by CSE. In addition, CSE activation promotes the phosphorylation modification of ATR, CHK1 proteins associated with DNA damage repair. The addition of PHA665752, a specific inhibitor of c-MET, or knock-down with c-MET both attenuated DNA damage, while overexpression of c-MET exacerbated DNA damage. Thus, c-MET phosphorylation may be involved in CSE-induced DNA damage, providing a potential target for intervention in the prevention and treatment of smoking-induced lung diseases.

Asunto(s)

Bronquios , Daño del ADN , Células Epiteliales , Nicotiana , Proteínas Proto-Oncogénicas c-met , Humo , Humanos , Proteínas Proto-Oncogénicas c-met/metabolismo , Fosforilación/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Bronquios/efectos de los fármacos , Bronquios/citología , Humo/efectos adversos , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/inducido químicamente , Línea Celular , Transducción de Señal/efectos de los fármacos , Productos de Tabaco

RESUMEN

Wheat leaf blight caused by Bipolaris sorokiniana is a widespread fungal disease that poses a serious risk to wheat. Biological control without causing environmental pollution is one of the safest and most effective method to control plant diseases. The antagonistic bacterial strain HeN-7 (identified as Bacillus velezensis) was isolated from tobacco leaves cultivated in Henan province, China. The results of different concentrations of cell-free supernatant (CFS) from HeN-7 culture against B. sorokiniana mycelia showed that 20% HeN-7 CFS (v/v) reached the maximum inhibition rate of 96%. In the potted plants control assay, B. velezensis HeN-7 CFS exhibited remarkable biocontrol activity on the wheat infected with B. sorokiniana, the best pot control efficacy was 65% at 20% CFS. The research on the mechanism of action demonstrated that HeN-7 CFS induced the membrane lipid peroxidation in B. sorokiniana, leading to the disruption of cell membrane integrity and resulting in the leakage of cell contents; in addition, the intracellular mitochondrial membrane potential in mycelium dissipated and reactive oxygen species accumulated, thereby inhibiting the growth of B. sorokiniana. These results indicate that B. velezensis HeN-7 is a promising candidate as a biological control agent against Bipolaris sorokiniana infection.

Asunto(s)

Bacillus , Bipolaris , Nicotiana , Enfermedades de las Plantas , Hojas de la Planta , Bacillus/aislamiento & purificación , Bacillus/metabolismo , Bacillus/fisiología , Hojas de la Planta/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Nicotiana/microbiología , Triticum/microbiología , Antifúngicos/farmacología , Antifúngicos/metabolismo , China , Especies Reactivas de Oxígeno/metabolismo , Micelio/crecimiento & desarrollo , Antibiosis

RESUMEN

Leaf senescence represents the final stage of leaf development, involving transcription factors (TFs)-mediated genetic reprogramming events. The timing of crop leaf senescence has a major influence on the yield and quality of crop in agricultural production. As important regulator of plant growth, the significance of TFs in the regulation of leaf senescence have been highlighted in various plant species by recent advances in genetics. However, studies on underlying molecular mechanisms are still not adequately explained. In this study, for analyzing the regulation of TFs on senescence of tobacco leaves, we combined gene differential expression analysis with weighted gene co-expression network analysis (WGCNA) to analyze the time-series gene expression profiles in senescing tobacco leaf. Among 3517 TF genes expressed in tobacco leaves, we identified 21, 35, and 183 TFs that were associated with early, middle, and late stages of tobacco leaf senescence, respectively. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation results reveal that these senescence response TFs are correlated with several biological pathways such as plant hormone signal transduction, ubiquitin mediated proteolysis and MAPK signaling pathway, indicating the roles of TFs in regulating leaf senescence. Our results provide implications for future studies of the potential regulatory mechanisms of TFs involved in senescence of tobacco leaves.

Asunto(s)

Regulación de la Expresión Génica de las Plantas , Nicotiana , Hojas de la Planta , Senescencia de la Planta , Factores de Transcripción , Nicotiana/genética , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Senescencia de la Planta/genética , Redes Reguladoras de Genes , Perfilación de la Expresión Génica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ontología de Genes , Transcriptoma

RESUMEN

Oral cancer is the most common malignancy in many developing countries, such as India, due to increased consumption of smokeless tobacco. The trace elemental components in commercially packaged forms of tobacco can play a significant role in the pathogenesis of oral cancer. To qualitatively assess the trace elements in various types of commercially packaged forms of tobacco using laser-induced breakdown spectroscopy (LIBS). Two popular varieties of 'Paan masala' that contained a mixture of slaked lime with areca nut, catechu, and other flavouring agents (tobacco was absent) and four types of packaged tobacco were obtained from 'Paan' shops. The contents in the packets were made into pellets using a hydraulic press and subjected to elemental analysis using LIBS. A ten-trial experiment was carried out on all six pellets. The National Institute of Standards and Technology (NIST) database was used to assess the emission lines. The elements obtained from commercially packaged tobacco and Paan masala were similar: calcium (Ca), iron (Fe), aluminium (Al), nickel (Ni), and chromium (Cr). Substances that cause DNA damage and carcinogenesis are inorganic elements such as nickel. Our study revealed that carcinogens such as nickel are present in the commercially packaged forms of tobacco and 'Paan masala' samples.

Asunto(s)

Nicotiana , Oligoelementos , Oligoelementos/análisis , Nicotiana/química , Análisis Espectral/métodos , Níquel/análisis , Rayos Láser , Productos de Tabaco/análisis , Embalaje de Productos , Tabaco sin Humo/análisis , Cromo/análisis , Calcio/análisis , Humanos , Hierro/análisis

RESUMEN

Roasted-rice leachate fermentation, a distinctive local tobacco fermentation method in Sichuan, imparts a mellow flavor and glossy texture to tobacco leaves, along with a roasted rice aroma. In order to find out the impact of roasted-rice leachate on cigar tobacco leaves, the physicochemical properties, volatile flavor profile, and microbial community were investigated. The content of protein significantly decreased after fermentation. The volatile flavor compounds increased following roasted-rice leachate fermentation, including aldehydes, alcohols, acids, and esters. High-throughput sequencing identified Staphylococcus, Pseudomonas, Pantoea, Oceanobacillus, Delftia, Corynebacterium, Sphingomonas, Aspergillus, Weissella, and Debaryomyces as the primary genera. Network and correlation analysis showed Debaryomyces played a crucial role in roasted-rice leachate fermentation, due to its numerous connections with other microbes and positive relationships with linoelaidic acid, aromandendrene, and benzaldehyde. This study is useful for gaining insight into the relationship between flavor compounds and microorganisms and provides references regarding the effect of extra nutrients on traditional fermentation products. KEY POINTS: • Volatile flavor compounds increased following roasted-rice leachate fermentation • Staphylococcus was the primary genera in fermented cigar • Debaryomyces may improve the quality of tobacco leaves.

Asunto(s)

Bacterias , Fermentación , Aromatizantes , Oryza , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/análisis , Aromatizantes/metabolismo , Oryza/microbiología , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Hojas de la Planta/microbiología , Productos de Tabaco , Gusto , Nicotiana/microbiología , Microbiota , Odorantes/análisis

RESUMEN

Drought poses a significant ecological threat that limits the production of crops worldwide. The objective of this study to examine the impact of soil applied biochar (BC) and peatmoss (PM) on the morpho-biochemical and quality traits of tobacco plants under drought conditions. In the present experiment work, a pot trial was conducted with two levels of drought severity (~ well-watered 75 ± 5% field capacity) and severe drought stress (~ 35 ± 5% field capacity), two levels of peatmoss (PM) @ 5% [PM+ (with peatmoss) and PM- (without peatmoss)] and three levels of rice straw biochar (BC0 = no biochar; BC1 = 150 mg kg- 1; and BC2 = 300 mg kg- 1 of soil) in tobacco plants. The results indicate that drought conditions significantly impacted the performance of tobacco plants. However, the combined approach of BC and PM significantly improved the growth, biomass, and total chlorophyll content (27.94%) and carotenoids (32.00%) of tobacco. This study further revealed that the drought conditions decreased the production of lipid peroxidation and proline accumulation. But the synergistic approach of BC and PM application increased soluble sugars (17.63 and 12.20%), soluble protein (31.16 and 15.88%), decreased the proline accumulation (13.92 and 9.03%), and MDA content (16.40 and 8.62%) under control and drought stressed conditions, respectively. Furthermore, the combined approach of BC and PM also improved the leaf potassium content (19.02%) by limiting the chloride ions (33.33%) under drought stressed conditions. Altogether, the balanced application of PM and BC has significant potential as an effective approach and sustainable method to increase the tolerance of tobacco plants subjected to drought conditions. This research uniquely highlights the combined potential of PM and BC as an eco-friendly strategy to enhance plant resilience under drought conditions, offering new insights into sustainable agricultural practices.

Asunto(s)

Carbón Orgánico , Sequías , Nicotiana , Nicotiana/fisiología , Clorofila/metabolismo , Estrés Fisiológico , Prolina/metabolismo , Suelo/química , Biomasa

RESUMEN

ADP-ribosylation (ADPRylation) is a mechanism which post-translationally modifies proteins in eukaryotes in order to regulate a broad range of biological processes including programmed cell death, cell signaling, DNA repair, and responses to biotic and abiotic stresses. Poly(ADP-ribosyl) polymerases (PARPs) play a key role in the process of ADPRylation, which modifies target proteins by attaching ADP-ribose molecules. Here, we investigated whether and how PARP1 and PARylation modulate responses of Nicotiana benthamiana plants to methyl viologen (MV)-induced oxidative stress. It was found that the burst of reactive oxygen species (ROS), cell death, and loss of tissue viability invoked by MV in N. benthamiana leaves was significantly delayed by both the RNA silencing of the PARP1 gene and by applying the pharmacological inhibitor 3-aminobenzamide (3AB) to inhibit PARylation activity. This in turn reduced the accumulation of PARylated proteins and significantly increased the gene expression of major ROS scavenging enzymes including SOD (NbMnSOD; mitochondrial manganese SOD), CAT (NbCAT2), GR (NbGR), and APX (NbAPX5), and inhibited cell death. This mechanism may be part of a broader network that regulates plant sensitivity to oxidative stress through various genetically programmed pathways.

Asunto(s)

Nicotiana , Estrés Oxidativo , Paraquat , Especies Reactivas de Oxígeno , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Paraquat/farmacología , Nicotiana/genética , Nicotiana/metabolismo , Poli ADP Ribosilación , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de los fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética

RESUMEN

Agropyron mongolicum Keng is a diploid perennial grass of triticeae in gramineae. It has strong drought resistance and developed roots that can effectively fix the soil and prevent soil erosion. GDSL lipase or esterases/lipase has a variety of functions, mainly focusing on plant abiotic stress response. In this study, a GDSL gene from A. mongolicum, designated as AmGDSL1, was successfully cloned and isolated. The subcellular localization of the AmGDSL1 gene (pCAMBIA1302-AmGDSL1-EGFP) results showed that the AmGDSL1 protein of A. mongolicum was only localized in the cytoplasm. When transferred into tobacco (Nicotiana benthamiana), the heterologous expression of AmGDSL1 led to enhanced drought tolerance. Under drought stress, AmGDSL1 overexpressing plants showed fewer wilting leaves, longer roots, and larger root surface area. These overexpression lines possessed higher superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and proline (PRO) activities. At the same time, the malondialdehyde (MDA) content was lower than that in wild-type (WT) tobacco. These findings shed light on the molecular mechanisms involved in the GDSL gene's role in drought resistance, contributing to the discovery and utilization of drought-resistant genes in A. mongolicum for enhancing crop drought resistance.

Asunto(s)

Agropyron , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Nicotiana , Proteínas de Plantas , Agropyron/genética , Agropyron/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Sequías , Estrés Fisiológico/genética , Plantas Modificadas Genéticamente/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Lipasa/metabolismo , Lipasa/genética

RESUMEN

The leaf apoplast contains several compounds that play important roles in the regulation of different physiological processes in plants. However, this compartment has been neglected in several experimental and modelling studies, which is mostly associated to the difficulty to collect apoplast washing fluid (AWF) in sufficient amount for metabolomics analysis and as free as possible from symplastic contamination. Here, we established an approach based in an infiltration-centrifugation technique that use little leaf material but allows sufficient AWF collection for gas chromatography mass spectrometry (GC-MS)-based metabolomics analysis in both tobacco and Arabidopsis. Up to 54 metabolites were annotated in leaf and apoplast samples from both species using either 20% (v/v) methanol (20% MeOH) or distilled deionized water (ddH2O) as infiltration fluids. The use of 20% MeOH increased the yield of the AWF collected but also the level of symplastic contamination, especially in Arabidopsis. We propose a correction factor and recommend the use of multiple markers such as MDH activity, protein content and conductivity measurements to verify the level of symplastic contamination in MeOH-based protocols. Neither the concentration of sugars nor the level of primary metabolites differed between apoplast samples extracted with ddH2O or 20% MeOH. This indicates that ddH2O can be preferentially used, given that it is a non-toxic and highly accessible infiltration fluid. The infiltration-centrifugation-based approach established here uses little leaf material and ddH2O as infiltration fluid, being suitable for GC-MS-based metabolomics analysis in tobacco and Arabidopsis, with great possibility to be extended for other plant species and tissues.

Asunto(s)

Arabidopsis , Cromatografía de Gases y Espectrometría de Masas , Metaboloma , Metabolómica , Nicotiana , Hojas de la Planta , Hojas de la Planta/metabolismo , Arabidopsis/metabolismo , Metabolómica/métodos , Nicotiana/metabolismo , Cromatografía de Gases y Espectrometría de Masas/métodos

RESUMEN

Plants produce reactive oxygen species (ROS) upon infection, which typically trigger defence mechanisms and impede pathogen proliferation. Root-knot nematodes (RKNs, Meloidogyne spp.) represent highly detrimental pathogens capable of parasitizing a broad spectrum of crops, resulting in substantial annual agricultural losses. The involvement of ROS in RKN parasitism is well acknowledged. In this study, we identified a novel effector from Meloidogyne incognita, named CATLe, that contains a conserved catalase domain, exhibiting potential functions in regulating host ROS levels. Phylogenetic analysis revealed that CATLe is conserved across RKNs. Temporal and spatial expression assays showed that the CATLe gene was specifically up-regulated at the early infection stages and accumulated in the subventral oesophageal gland cells of M. incognita. Immunolocalization demonstrated that CATLe was secreted into the giant cells of the host plant during M. incognita parasitism. Transient expression of CATLe significantly dampened the flg22-induced ROS production in Nicotiana benthamiana. In planta assays confirmed that M. incognita can exploit CATLe to manipulate host ROS levels by directly degrading H2O2. Additionally, interfering with expression of the CATLe gene through double-stranded RNA soaking and host-induced gene silencing significantly attenuated M. incognita parasitism, highlighting the important role of CATLe. Taken together, our results suggest that RKNs can directly degrade ROS products using a functional catalase, thereby manipulating host ROS levels and facilitating parasitism.

Asunto(s)

Catalasa , Peróxido de Hidrógeno , Nicotiana , Especies Reactivas de Oxígeno , Tylenchoidea , Animales , Peróxido de Hidrógeno/metabolismo , Tylenchoidea/fisiología , Especies Reactivas de Oxígeno/metabolismo , Nicotiana/parasitología , Catalasa/metabolismo , Catalasa/genética , Enfermedades de las Plantas/parasitología , Raíces de Plantas/parasitología , Filogenia , Proteínas del Helminto/metabolismo , Proteínas del Helminto/genética , Interacciones Huésped-Parásitos

RESUMEN

Pathogenesis-related proteins (PR), including osmotins, play a vital role in plant defense, being activated in response to diverse biotic and abiotic stresses. Despite their significance, the mechanistic insights into the role of osmotins in plant defense have not been extensively explored. The present study explores the cloning and characterization of the osmotin gene (WsOsm) from Withania somnifera, aiming to illuminate its role in plant defense mechanisms. Quantitative real-time PCR analysis revealed significant induction of WsOsm in response to various phytohormones e.g. abscisic acid, salicylic acid, methyl jasmonate, brassinosteroids, and ethrel, as well as biotic and abiotic stresses like heat, cold, salt, and drought. To further elucidate WsOsm's functional role, we overexpressed the gene in Nicotiana tabacum, resulting in heightened resistance against the Alternaria solani pathogen. Additionally, we observed enhancements in shoot length, root length, and root biomass in the transgenic tobacco plants compared to wild plants. Notably, the WsOsm- overexpressing seedlings demonstrated improved salt and drought stress tolerance, particularly at the seedling stage. Confocal histological analysis of H2O2 and biochemical studies of antioxidant enzyme activities revealed higher levels in the WsOsm overexpressing lines, indicating enhanced antioxidant defense. Furthermore, a pull-down assay and mass spectrometry analysis revealed a potential interaction between WsOsm and defensin, a known antifungal PR protein (WsDF). This suggests a novel role of WsOsm in mediating plant defense responses by interacting with other PR proteins. Overall, these findings pave the way for potential future applications of WsOsm in developing stress-tolerant crops and improving plant defense strategies against pathogens.

Asunto(s)

Defensinas , Regulación de la Expresión Génica de las Plantas , Nicotiana , Proteínas de Plantas , Plantas Modificadas Genéticamente , Estrés Fisiológico , Withania , Withania/genética , Withania/fisiología , Withania/metabolismo , Withania/efectos de los fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/fisiología , Nicotiana/efectos de los fármacos , Nicotiana/microbiología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Estrés Fisiológico/genética , Defensinas/genética , Defensinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Alternaria/fisiología , Sequías , Plantones/genética , Plantones/fisiología , Plantones/efectos de los fármacos , Ácido Salicílico/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Peróxido de Hidrógeno/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Raíces de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/fisiología

RESUMEN

Although deterioration of silicone maxillofacial prostheses is severely accentuated in smoking patients, the phenomenon has not been systematically studied. To address a gap in the literature concerning the stability of maxillofacial prostheses during service, in this contribution, the effect of cigarette smoke on the aspect and physical properties of M511 silicone elastomer was evaluated. The aspect, surface, and overall properties of the silicone material, pigmented or not, were followed by AFM, color measurements, FTIR, water contact angle measurements, TGA-DTG and DSC, hardness and compression stress-strain measurements. The types of the contaminants adsorbed were assessed by XRF, ESI-MS, MALDI-MS, and NMR spectral analyses. Important modifications in color, contact angle, surface roughness, local mechanical properties, and thermal properties were found in the silicone material for maxillofacial prostheses after exposure to cigarettes smoke. The presence of lead, nicotine, and several other organic compounds adsorbed into the silicone material was emphasized. Slight decrease in hardness and increase in Young's modulus was found. The combined data show important impact of cigarette smoke on the silicone physical properties and could indicate chemical transformations by secondary cross-linking. To our knowledge, this is the first study making use of complementary physical methods to assess the effect of cigarette smoke on the aspect and integrity of silicone materials for maxillofacial prostheses.

Asunto(s)

Ensayo de Materiales , Prótesis Maxilofacial , Humo , Humanos , Elastómeros de Silicona/química , Nicotiana/química , Color

RESUMEN

East Asian Passiflora virus (EAPV) causes passionfruit woodiness disease, a major threat limiting passionfruit production in eastern Asia, including Taiwan and Vietnam. In this study, an infectious cDNA clone of a Taiwanese severe isolate EAPV-TW was tagged with a green fluorescent protein (GFP) reporter to monitor the virus in plants. Nicotiana benthamiana and yellow passionfruit plants inoculated with the construct showed typical symptoms of EAPV-TW. Based on our previous studies on pathogenicity determinants of potyviral HC-Pros, a deletion of six amino acids (d6) alone and its association with a point mutation (F8I, simplified as I8) were conducted in the N-terminal region of the HC-Pro gene of EAPV-TW to generate mutants of EAPV-d6 and EAPV-d6I8, respectively. The mutant EAPV-d6I8 caused infection without conspicuous symptoms in N. benthamiana and yellow passionfruit plants, while EAPV-d6 still induced slight leaf mottling. EAPV-d6I8 was stable after six passages under greenhouse conditions and displayed a zigzag pattern of virus accumulation, typical of a beneficial protective virus. The cross-protection effectiveness of EAPV-d6I8 was evaluated in both N. benthamiana and yellow passionfruit plants under greenhouse conditions. EAPV-d6I8 conferred complete cross-protection (100%) against the wild-type EAPV-TW-GFP in both N. benthamiana and yellow passionfruit plants, as verified by no severe symptoms, no fluorescent signals, and PCR-negative status for GFP. Furthermore, EAPV-d6I8 also provided complete protection against Vietnam's severe strain EAPV-GL1 in yellow passionfruit plants. Our results indicate that the attenuated mutant EAPV-d6I8 has great potential to control EAPV in Taiwan and Vietnam via cross-protection.

Asunto(s)

Mutación , Enfermedades de las Plantas , Potyvirus , Proteínas Virales , Protección Cruzada , Cisteína Endopeptidasas , Nicotiana/virología , Nicotiana/genética , Passiflora/virología , Passiflora/genética , Enfermedades de las Plantas/virología , Enfermedades de las Plantas/prevención & control , Potyvirus/genética , Eliminación de Secuencia , Taiwán , Vietnam , Proteínas Virales/genética , Proteínas Virales/metabolismo

Asunto(s)

Nicotiana , Productos de Tabaco , Historia del Siglo XX , Nicotina/efectos adversos , Nicotina/aislamiento & purificación , Industria del Tabaco/historia , Productos de Tabaco/historia , Nicotiana/química

RESUMEN

Citrus huanglongbing (HLB) has been causing enormous damage to the global citrus industry. As the main causal agent, 'Candidatus Liberibacter asiaticus' (CLas) delivers a set of effectors to modulate host responses, while the modes of action adopted remain largely unclear. Here, we demonstrated that CLIBASIA_00185 (CLas0185) could attenuate reactive oxygen species (ROS)-mediated cell death in Nicotiana benthamiana. Transgenic expression of CLas0185 in Citrus sinensis 'Wanjincheng' enhanced plant susceptibility to CLas. We found that methionine sulphoxide reductase B1 (CsMsrB1) was targeted by the effector, and its abundance was elevated in CLas0185-transgenic citrus plants. Their interaction promoted CLas proliferation. We then determined that CsMsrB1 sustained redox state and enzymatic activity of ascorbate peroxidase 1 (CsAPX1) under oxidative stress. The latter reduced H2O2 accumulation and was associated with host susceptibility to CLas infection. Consistently, citrus plants expressing CLas0185 and CsMsrB1 conferred enhanced APX activity and decreased H2O2 content. Taken together, these findings revealed how CLas0185 benefits CLas colonization by targeting CsMsrB1, which facilitated the antioxidant activity and depressed ROS during pathogen infection.

Asunto(s)

Ascorbato Peroxidasas , Citrus sinensis , Metionina Sulfóxido Reductasas , Enfermedades de las Plantas , Enfermedades de las Plantas/microbiología , Citrus sinensis/microbiología , Ascorbato Peroxidasas/metabolismo , Metionina Sulfóxido Reductasas/metabolismo , Metionina Sulfóxido Reductasas/genética , Especies Reactivas de Oxígeno/metabolismo , Plantas Modificadas Genéticamente , Nicotiana/microbiología , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Rhizobiaceae/fisiología , Peróxido de Hidrógeno/metabolismo , Liberibacter , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética

RESUMEN

In recent years, nanocarrier-based pesticide delivery systems have provided new possibilities for the efficient utilization of pesticides. In this research, we developed a hydroxypropyl-ß-cyclodextrin-modified graphene oxide (GO-HP-ß-CD) nanocarrier for pyraclostrobin (Pyr) delivery and studied its application for tobacco target spot disease control. GO-HP-ß-CD has excellent pesticide-loading performance for Pyr (adsorption capacity of 1562.5 mg/g) and good water dispersibility and stability. Besides, GO-HP-ß-CD shows pH-responsive release performance. In addition, GO-HP-ß-CD also has better leaf affinity than Pyr, and it can effectively adhere to the leaf surface after simulated washing. The results of antifungal experiments indicate that GO-HP-ß-CD-Pyr has a good preventive effect on tobacco target spot disease, and its EC50 value is 0.384 mg/L, which is lower than Pyr. Specifically, this nanopesticide formulation does not contain toxic organic solvent or additive, so it has good environmental friendliness. Therefore, we believe that the GO-HP-ß-CD-Pyr nanopesticide has brilliant potential in the prevention and control of tobacco diseases.

Asunto(s)

Grafito , Nicotiana , Estrobilurinas , Grafito/química , Nicotiana/química , Estrobilurinas/química , Antifúngicos/química , Antifúngicos/farmacología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , Carbamatos/química , Portadores de Fármacos/química , Plaguicidas/química , beta-Ciclodextrinas/química , Fungicidas Industriales/química , Fungicidas Industriales/farmacología

RESUMEN

Grapevine leafroll-associated virus 3 (GLRaV-3) is a formidable threat to the stability of the global grape and wine industries. It is the primary etiological agent of grapevine leafroll disease (GLD) and significantly impairs vine health, fruit quality, and yield. GLRaV-3 is a member of the genus Ampelovirus, Closteroviridae family. Viral genes within the 3' proximal unique gene blocks (UGB) remain highly variable and poorly understood. The UGBs of Closteroviridae viruses include diverse open reading frames (ORFs) that have been shown to contribute to viral functions such as the suppression of the host RNA silencing defense response and systemic viral spread. This study investigates the role of GLRaV-3 ORF8, ORF9, and ORF10, which encode the proteins p21, p20A, and p20B, respectively. These genes represent largely unexplored facets of the GLRaV-3 genome. Here, we visualize the subcellular localization of wildtype and mutagenized GLRaV-3 ORFs 8, 9, and 10, transiently expressed in Nicotiana benthamiana. Our results indicate that p21 localizes to the cytosol, p20A associates with microtubules, and p20B is trafficked into the nucleus to carry out the suppression of host RNA silencing. The findings presented herein provide a foundation for future research aimed at the characterization of the functions of these ORFs. In the long run, it would also facilitate the development of innovative strategies to understand GLRaV-3, mitigate its spread, and impacts on grapevines and the global wine industry.

Asunto(s)

Nicotiana , Proteínas Virales , Nicotiana/genética , Nicotiana/virología , Nicotiana/metabolismo , Proteínas Virales/metabolismo , Proteínas Virales/genética , Enfermedades de las Plantas/virología , Enfermedades de las Plantas/genética , Sistemas de Lectura Abierta/genética , Vitis/genética , Vitis/virología , Vitis/metabolismo , Closteroviridae/genética , Closteroviridae/metabolismo

RESUMEN

Potato is one of the four staple food crops in the world. It has a wide range of cultivation, high yield, and high nutritional value. Enhancing the photosynthesis of potato is particularly important as it leads to an increase in the potato yield. The light-harvesting pigment-binding protein complex is very important for plant photosynthesis. We identified 12 Stlhcb gene family members from the potato variety "Atlantic" using transcriptome sequencing and bioinformatics. The proteins encoded by the Stlhcb gene family have between 3358 and 4852 atomic number, a relative molecular weight between 24060.16 and 34624.54 Da, and an isoelectric point between 4.99 and 8.65. The RT-qPCR results showed that the 12 Stlhcb genes were expressed in a tissue-specific and time-dependent fashion under low light. The relative expression of the Stlhcb genes in the leaves was significantly higher than that in the stems and roots, and the relative expression of these genes first increased and then decreased with the prolongation of light exposure time. The Stcp24 gene with the highest expression was cloned, and an expression vector was constructed. A subcellular localization analysis was performed in tobacco and an overexpression experiment was performed in potato using an Agrobacterium-mediated method. The subcellular localization analysis showed that the protein encoded by Stcp24 was located in chloroplasts as expected. Overexpression of Stcp24 in transgenic potato increased the yield of potatoes and the content of chlorophyll a and b; increased the net photosynthetic rate, transpiration rate, stomatal conductance, electron transport efficiency, and semi-saturated light intensity; and promoted photosynthesis and plant growth. This study provides a reference for the study of the function of the potato light-harvesting pigment-binding protein gene family. It lays a foundation for further study of the mechanism of the photosynthesis of potato, improvement of the light energy utilization of potato, and molecular breeding of potato.

Asunto(s)

Regulación de la Expresión Génica de las Plantas , Fotosíntesis , Proteínas de Plantas , Solanum tuberosum , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Solanum tuberosum/crecimiento & desarrollo , Fotosíntesis/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Familia de Multigenes , Clorofila/metabolismo , Complejos de Proteína Captadores de Luz/genética , Complejos de Proteína Captadores de Luz/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Filogenia