Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 72
Filtrar
Más filtros










Intervalo de año de publicación
1.
Phytochemistry ; 223: 114117, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38697243

RESUMEN

Cembranoids and labdanes are two important types of diterpenes in tobacco (Nicotiana genus) that are predominantly found in the leaf and flower glandular trichome secretions. This is the first systematic review of the biosynthesis, chemical structures, bioactivities, and utilisation values of cembranoid and labdane diterpenes in tobacco. A total of 131 natural cembranoid diterpenes have been reported in tobacco since 1962; these were summarised and classified according to their chemical structure characteristics as isopropyl cembranoids (1-88), seco-cembranoids (89-103), chain cembranoids (104-123), and polycyclic cembranoids (124-131). Forty natural labdane diterpenes reported since 1961 were also summarised and divided into epoxy side chain labdanes (132-150) and epoxy-free side chain labdanes (151-171). Tobacco cembranoid and labdane diterpenes are both formed via the methylerythritol 4-phosphate pathway and are synthesised from geranylgeranyl diphosphate. Their biosynthetic pathways and the four key enzymes (cembratrienol synthase, cytochrome P450 hydroxylase, copalyl diphosphate synthase, and Z-abienol cyclase) that affect their biosynthesis have been described in detail. A systematic summary of the bioactivity and utilisation values of the cembranoid and labdane diterpenes is also provided. The agricultural bioactivities associated with cembranoid and labdane diterpenes include antimicrobial and insecticidal activities as well as induced resistance, while the medical bioactivities include cytotoxic and neuroprotective activities. Further research into the cembranoid and labdane diterpenes will help to promote their development and utilisation as plant-derived pesticides and medicines.

2.
Front Bioeng Biotechnol ; 12: 1358246, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38419725

RESUMEN

With the rapid development of synthetic biology, recombinant human collagen has emerged as a cutting-edge biological material globally. Its innovative applications in the fields of material science and medicine have opened new horizons in biomedical research. Recombinant human collagen stands out as a highly promising biomaterial, playing a pivotal role in crucial areas such as wound healing, stroma regeneration, and orthopedics. However, realizing its full potential by efficiently delivering it for optimal therapeutic outcomes remains a formidable challenge. This review provides a comprehensive overview of the applications of recombinant human collagen in biomedical systems, focusing on resolving this crucial issue. Additionally, it encompasses the exploration of 3D printing technologies incorporating recombinant collagen to address some urgent clinical challenges in regenerative repair in the future. The primary aim of this review also is to spotlight the advancements in the realm of biomaterials utilizing recombinant collagen, with the intention of fostering additional innovation and making significant contributions to the enhancement of regenerative biomaterials, therapeutic methodologies, and overall patient outcomes.

3.
Autoimmunity ; 56(1): 2250095, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37621179

RESUMEN

Lupus nephritis (LN) is a major cause death in patients with systemic lupus erythematosus. We aimed to find the differentially expressed genes (DEGs) in LN and confirm the regulatory mechanism on LN. The mouse model of LN was constructed by subcutaneous injection of pristane. RNA-seq screened 392 up-regulated and 447 down-regulated DEGs in LN mouse model, and KEGG analysis found that the top 20 DEGs were enriched in arachidonic acid metabolism, tryptophan metabolism, etc. The hub genes, Kynu, Spidr, Gbp3, Cbr1, Cyp4b1, and Cndp2 were identified, in which Gbp3 was selected for following study. Afterwards, the function of Gbp3 on the proliferation, inflammation, and pyroptosis of LN was verified by CCK-8, ELISA, and WB in vitro. The results demonstrated that si-Gbp3 promoted cell proliferation and inhibited the levels of inflammatory factors (IL-1ß, TNF-α and IL-8) and pyroptosis-related proteins (GSDMD, Caspase-1 and NLRP3) in a cell model of LN. In constrast, Gbp3 overexpression played an opposite role. In summary, Gbp3 promoted the progression of LN via inhibiting cell proliferation and facilitating inflammation and pyroptosis.


Asunto(s)
Lupus Eritematoso Sistémico , Nefritis Lúpica , Animales , Ratones , Nefritis Lúpica/genética , Piroptosis , Inflamación/genética , Proliferación Celular , Modelos Animales de Enfermedad , Proteínas de Unión al GTP
4.
Int J Mol Sci ; 24(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37569602

RESUMEN

Bacterial wilt negatively impacts the yield and quality of tomatoes. cis-Abienol, a labdane diterpenoid abundantly produced in the trichome secretion of Nicotiana spp., can induce bacterial wilt resistance in plants; however, study on its practical application and acting mechanism is very limited. This study established the application conditions of cis-abienol for inducing tomato bacterial wilt resistance by pot-inoculation experiments and investigated the underlying mechanism by determining the physio-biochemical indexes and transcriptomic changes. The results showed that applying cis-abienol to the roots was the most effective approach for inducing tomato bacterial wilt resistance. The optimal concentration was 60 µg/mL, and 2-3 consecutive applications with 3-6 days intervals were sufficient to induce the bacterial wilt resistance of tomato plants. cis-Abienol could enhance the antioxidant enzyme activity and stimulate the defensive signal transduction in tomato roots, leading to the upregulation of genes involved in the mitogen-activated protein kinase cascade. It also upregulated the expression of JAZ genes and increased the content of jasmonic acid (JA) and salicylic acid (SA), which control the expression of flavonoid biosynthetic genes and the content of phytoalexins in tomato roots. cis-Abienol-induced resistance mainly depends on the JA signalling pathway, and the SA signalling pathway is also involved in this process. This study established the feasibility of applying the plant-derived terpenoid cis-abienol to induce plant bacterial wilt resistance, which is of great value for developing eco-friendly bactericides.


Asunto(s)
Diterpenos , Solanum lycopersicum , Nicotiana/genética , Nicotiana/metabolismo , Solanum lycopersicum/genética , Transducción de Señal , Diterpenos/farmacología , Ácido Salicílico/metabolismo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas
5.
Molecules ; 28(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37570785

RESUMEN

The photocatalytic degradation of formaldehyde by graphite-like C3N4 is one of the most attractive and environmentally friendly strategies to address the significant threat to human health posed by indoor air pollutants. Despite its potential, this degradation process still faces issues with suboptimal efficiency, which may be attributed to the rapid recombination of photogenerated excitons and the broad band gap. As a proof of concept, a series of graphite-like C3N4@C60 composites combining graphite-like C3N4 and C60 was developed via an in situ generation strategy. The obtained graphite-like C3N4@C60 composites exhibited a remarkable increase in the photocatalytic degradation efficiency of formaldehyde, of up to 99%, under visible light irradiation, outperforming pure graphite-like C3N4 and C60. This may be due to the composites' enhanced built-in electric field. Additionally, the proposed composites maintained a formaldehyde removal efficiency of 84% even after six cycles, highlighting their potential for indoor air purification and paving the way for the development of efficient photocatalysts.

6.
Front Plant Sci ; 14: 1183739, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324716

RESUMEN

Wild rice (Zizania spp.), an aquatic grass belonging to the subfamily Gramineae, has a high economic value. Zizania provides food (such as grains and vegetables), a habitat for wild animals, and paper-making pulps, possesses certain medicinal values, and helps control water eutrophication. Zizania is an ideal resource for expanding and enriching a rice breeding gene bank to naturally preserve valuable characteristics lost during domestication. With the Z. latifolia and Z. palustris genomes completely sequenced, fundamental achievements have been made toward understanding the origin and domestication, as well as the genetic basis of important agronomic traits of this genus, substantially accelerating the domestication of this wild plant. The present review summarizes the research results on the edible history, economic value, domestication, breeding, omics research, and important genes of Z. latifolia and Z. palustris over the past decades. These findings broaden the collective understanding of Zizania domestication and breeding, furthering human domestication, improvement, and long-term sustainability of wild plant cultivation.

7.
Sci Total Environ ; 884: 163741, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37120025

RESUMEN

Wood-based panels provide efficient alternatives to materials such as plastics derived from traditional petroleum sources and thereby help to mitigate greenhouse gas emissions. Unfortunately, using indoor manufactured panel products also results in significant emissions of volatile organic compounds including olefins, aromatic and ester compounds, which negatively affect human health. This paper highlights recent developments and notable achievements in the field of indoor hazardous air treatment technologies to guide future research toward environmentally friendly and economically feasible directions that may have a significant impact on the improvement of human settlements. Summarizing and synthesizing the principles, advantages, and limitations of different technologies can assist policymakers and engineers in identifying the most appropriate technology for a particular air pollution control program based on criteria such as cost-effectiveness, efficiency, and environmental impact. In addition, insights into the development of indoor air pollution control technologies are provided and potential areas for innovation, improvement of existing technologies, and development of new technologies are identified. Finally, the authors also hope that this sub-paper will raise public awareness of indoor air pollution issues and promote a better understanding of the importance of indoor air pollution control technologies for public health, environmental protection, and sustainable development.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Petróleo , Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Madera/química , Contaminación del Aire Interior/prevención & control , Contaminación del Aire Interior/análisis , Ambiente , Contaminantes Atmosféricos/análisis
8.
ACS Appl Mater Interfaces ; 15(3): 4505-4515, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36629909

RESUMEN

The preparation of biocomposites from renewable and sustainable forestry residues is an effective method to significantly reduce the environmental pollution caused by synthetic materials such as plastics and synthetic fibers. This study is aimed at developing a clean process for the large-scale production of high-performance green biocomposites without involving any chemical adhesive. Adhesive-free biocomposites with superior mechanical properties were prepared using HCl ball milling pretreatment and in situ synthesis. The nano-Fe3O4 was uniformly dispersed in the cellulose matrix, and when the matrix was subjected to external forces, the stress concentration effect around the particles absorbed energy, thus effectively improving the mechanical strength of the matrix. The flexural strength and tensile strength of BWP(Fe3O4) samples were increased by 159.04 and 175.34%, compared to that of regular wood powder control samples. The lignin melts under high temperature and pressure and then forms a carbonized layer on the surface of the biocomposites during the cooling process, which prevents the rapid penetration of water from the surface and also gives the biocomposites good thermal stability. The results of this research can avoid the harmful volatiles generated by chemical adhesive than that of the traditional fiberboard process and effectively replace petroleum-based synthetic materials prepared using the addition of various chemical additives, making it conform to the concept of environmental protection and sustainability.

9.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36555582

RESUMEN

The loss of seed shattering is an important event in crop domestication, and elucidating the genetic mechanisms underlying seed shattering can help reduce yield loss during crop production. This study is the first to systematically identify and analyse the BELL family of transcription factor-encoding genes in Chinese wild rice (Zizania latifolia). ZlqSH1a (Zla04G033720) and ZlqSH1b (Zla02G027130) were identified as key candidate genes involved in seed shattering in Z. latifolia. These genes were involved in regulating the development of the abscission layer (AL) and were located in the nucleus of the cell. Over-expression of ZlqSH1a and ZlqSH1b resulted in a complete AL between the grain and pedicel and significantly enhanced seed shattering after grain maturation in rice. Transcriptome sequencing revealed that 172 genes were differentially expressed between the wild type (WT) and the two transgenic (ZlqSH1a and ZlqSH1b over-expressing) plants. Three of the differentially expressed genes related to seed shattering were validated using qRT-PCR analysis. These results indicate that ZlqSH1a and ZlqSH1b are involved in AL development in rice grains, thereby regulating seed shattering. Our results could facilitate the genetic improvement of seed-shattering behaviour in Z. latifolia and other cereal crops.


Asunto(s)
Oryza , Domesticación , Genes de Plantas , Semillas , Grano Comestible/genética
10.
Food Res Int ; 162(Pt B): 112082, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36461331

RESUMEN

Chinese wild rice (Zizania latifolia) is rich in flavonoids and the characteristic colour of its pericarp is attributed to the flavonoids. In this study, the molecular basis of the colour change in the pericarp of Chinese wild rice was studied using metabolomics and proteomics. Whole seeds in three developmental stages (10, 20, and 30 days after flowering) were characterised based on phenolic contents, free amino acids (FAAs), and the expression level and activities of enzymes critical in flavonoid biosynthesis. The total phenolic and proanthocyanidin contents of Chinese wild rice increased gradually, whereas total flavonoid and FAA contents decreased during seed development. Metabolomic analysis revealed gradual upward trends for 57 flavonoids (sub classes 1, 3, and 10) related to colour change in the pericarp. Proteomic analysis showed that the phenylpropanoid biosynthesis metabolic pathway was enriched with differentially expressed proteins and was associated with flavonoid biosynthesis. Proteomic data suggested that leucoanthocyanidin reductase and WD40 repeat protein may be involved in flavonoid biosynthesis in Chinese wild rice, which was also verified by real-time quantitative PCR. Our results provide new insights into the understanding of the colour formation in the pericarp of Chinese wild rice.


Asunto(s)
Oryza , China , Color , Flavonoides , Oryza/genética , Fenoles , Poaceae , Proteómica
11.
ACS Appl Mater Interfaces ; 14(41): 47176-47187, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36214472

RESUMEN

Traditional wood-based panels are usually made from large-diameter trees and rely on adhesives for compactness, which negatively impacts the environment and human health. However, the widely distributed small-diameter shrubs are good raw materials for wood-based panels with abundant fibers, but are often under-exploited. This research reports the preparation of self-bonding biocomposites from Buxus sinica by an innovative combined approach of extraction, alkali treatment, and hot molding. The resulted biocomposites show better mechanical properties in which the flexural modulus (7.79 GPa) and the tensile modulus (4.33 GPa) were 5 times and 1.7 times higher than the conventional fiberboard, respectively, and also demonstrated better hydrophobicity than fiberboard, which could be due to the layer of lignin that formed on its surface preventing the infiltration of water. To sum up, the biocomposites prepared from small-diameter shrubs meet the requirement of the furniture and architectural decoration materials, suggesting that the proposed approach can be used to produce high-performance biocomposites.


Asunto(s)
Buxus , Lignina , Humanos , Diseño Interior y Mobiliario , Informe de Investigación , Álcalis , Agua
12.
Front Microbiol ; 13: 1026680, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312940

RESUMEN

Tobacco contains a large amount of bioactive ingredients which can be used as source of feed. The objective of this study was to evaluate the effects of dietary addition of low-nicotine tobacco (LNT) on the growth performance, blood status, cecum microbiota and metabolite composition of meat rabbits. A total of 80 Kangda meat rabbits of similar weight were assigned randomly as four groups, and three of them were supplemented with 5%, 10%, and 20% LNT, respectively, with the other one fed with basal diet as control group. Each experiment group with 20 rabbits was raised in a single cage. The experiments lasted for 40 days with a predictive period of 7 days. The results revealed that LNT supplementation had no significant effect on the growth performance, but increased the half carcass weight compared with control group. Dietary supplemention of LNT decreased the triglycerides and cholesterol content in rabbit serum, and significantly increased the plasma concentration of lymphocytes (LYM), monocytes, eosinophils, hemoglobin HGB and red blood cells. In addition, LNT supplementation significantly changed the microbial diversity and richness, and metagenomic analysis showed that LNT supplementation significantly increased Eubacterium_siraeum_group, Alistipes, Monoglobus and Marvinbryantia at genus level. Moreover, LC-MS data analysis identified a total of 308 metabolites that markedly differed after LNT addition, with 190 significantly upregulated metabolites and 118 significantly downregulated metabolites. Furthermore, the correlation analysis showed that there was a significant correlation between the microbial difference and the rabbit growth performance. Overall, these findings provide theoretical basis and data support for the application of LNT in rabbits.

13.
Carbohydr Polym ; 297: 120025, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36184173

RESUMEN

Pectin is a major component in many agricultural feedstocks. Despite the wide use in industrial production of cellulases and hemicellulases, the fungus Trichoderma reesei lacks a complete enzyme set for pectin degradation. In this study, three representative pectinolytic enzymes were expressed and screened for their abilities to improve the efficiency of T. reesei enzymes on the conversion of different agricultural residues. By replacing 5 % of the T. reesei proteins, endopolygalacturonase and pectin lyase remarkably increased the release of sugars from inferior tobacco leaves. In contrast, pectin methylesterase showed the strongest improving effect (by 31.1 %) on the hydrolysis of beetroot residue. The pectin in beetroot residue was only mildly degraded with the supplementation of pectin methylesterase, which allowed the extraction of pectin keeping the original emulsifying activity with a 51.1 % higher yield. The results provide a basis for precise optimization of lignocellulolytic enzyme systems for targeted valorization of pectin-rich agricultural residues.


Asunto(s)
Celulasa , Celulasas , Trichoderma , Biomasa , Celulasa/metabolismo , Celulasas/metabolismo , Hidrólisis , Pectinas/metabolismo , Poligalacturonasa/metabolismo , Azúcares/metabolismo
14.
Polymers (Basel) ; 14(17)2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36080653

RESUMEN

Fast-growing poplar with low wood density has been generally regarded as a low-grade wood species and cannot be used as a building material due to its poor fire resistance. As the fire resistance of wood materials is positively correlated with density, combined treatment using resin impregnation, which imparts thermal resistance, and compression, which improves density, appeared to be a route toward improved combustion performance. Fast-growing poplar wood was modified with a combination of borate-containing phenol-formaldehyde resin impregnation and compression in a transverse direction at varying intensities. The effects of the combined treatment on fire resistance were then examined and discussed. Char residue morphology analysis and microscopic observations were conducted to reveal the effects and mechanism of the combined treatment on fire resistance improvement. The test results showed that fire resistance was greatly improved, including the static and dynamic bending performance at elevated and high temperatures, as well as the combustion performance. The higher the compression ratio was, the better the fire resistance of the modified wood.

15.
Polymers (Basel) ; 14(10)2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35631935

RESUMEN

Cellulose has attracted considerable attention as the most promising potential candidate raw material for the production of bio-based polymeric materials. In the last decade, significant progress has been made in the production of biopolymers based on different cellulose forms. In this study, cellulose was obtained in an innovative and environmentally friendly way, using boxwood powder. Crude cellulose was obtained by treating Buxus powder with an ethanol-acetic acid-water mixture. Refined cellulose was then obtained by treatment with an acidic sodium hypochlorite solution and alkaline hydrogen peroxide solution. The novel chemistry of cellulose prepared by this method promises to be not only green, but also highly desirable, because of its lower emissions and low cost. It is crucial for the future of the global polymer industry. The refined cellulose was subjected to a high-temperature hydrothermal treatment under two temperatures and time conditions, with temperature gradients of 120, 140, and 160 °C, and time gradients of 1, 2, and 3 h. The samples were subjected to infrared and thermogravimetric analyses. The cellulose undergoes dehydration and thermal degradation reactions during the heat treatment process, and the thermal stability of the residual is enhanced, compared with that of virgin cellulose. Between 120 and 140 °C, the hydroxyl and hypomethyl groups on the surface of cellulose are shed. Groups in the amorphous region of the polymer are the first to be shed. The dehydration reaction reduces the number of free hydroxyl groups on the surface of the cellulose molecules. The dehydration reaction was accelerated by an increase in temperature. Between 140 and 160 °C, the ß-(1,4)-glycosidic bond begins to slowly break and some furans are generated. The structure of cellulose undergoes reorganization during thermal treatment. The thermal stability of the modified material is greater than that of untreated cellulose.

16.
Sensors (Basel) ; 22(8)2022 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-35459079

RESUMEN

We propose a method for minimizing global buffer access within a deep learning accelerator for convolution operations by maximizing the data reuse through a local register file, thereby substituting the local register file access for the power-hungry global buffer access. To fully exploit the merits of data reuse, this study proposes a rearrangement of the computational sequence in a deep learning accelerator. Once input data are read from the global buffer, repeatedly reading the same data is performed only through the local register file, saving significant power consumption. Furthermore, different from prior works that equip local register files in each computation unit, the proposed method enables sharing a local register file along the column of the 2D computation array, saving resources and controlling overhead. The proposed accelerator is implemented on an off-the-shelf field-programmable gate array to verify the functionality and resource utilization. Then, the performance improvement of the proposed method is demonstrated relative to popular deep learning accelerators. Our evaluation indicates that the proposed deep learning accelerator reduces the number of global-buffer accesses to nearly 86.8%, consequently saving up to 72.3% of the power consumption for the input data memory access with a minor increase in resource usage compared to a conventional deep learning accelerator.


Asunto(s)
Aprendizaje Profundo , Registros
17.
Commun Biol ; 5(1): 36, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35017643

RESUMEN

Chinese wild rice (Zizania latifolia; family: Gramineae) is a valuable medicinal homologous grain in East and Southeast Asia. Here, using Nanopore sequencing and Hi-C scaffolding, we generated a 547.38 Mb chromosome-level genome assembly comprising 332 contigs and 164 scaffolds (contig N50 = 4.48 Mb; scaffold N50 = 32.79 Mb). The genome harbors 38,852 genes, with 52.89% of the genome comprising repetitive sequences. Phylogenetic analyses revealed close relation of Z. latifolia to Leersia perrieri and Oryza species, with a divergence time of 19.7-31.0 million years. Collinearity and transcriptome analyses revealed candidate genes related to seed shattering, providing basic information on abscission layer formation and degradation in Z. latifolia. Moreover, two genomic blocks in the Z. latifolia genome showed good synteny with the rice phytocassane biosynthetic gene cluster. The updated genome will support future studies on the genetic improvement of Chinese wild rice and comparative analyses between Z. latifolia and other plants.


Asunto(s)
Cromosomas de las Plantas/genética , Genoma de Planta/genética , Poaceae/genética , Semillas/genética , China , Oryza/genética , Filogenia , Poaceae/metabolismo
18.
Plant Cell Physiol ; 63(1): 45-56, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-34523687

RESUMEN

Jasmonate (JA)-induced plant senescence has been mainly studied with a dark/starvation-promoted system using detached leaves; yet, the induction of whole-plant senescence by JA remains largely unclear. This work reports the finding of a JA-induced whole-plant senescence of tobacco under light/non-starvation conditions and the investigation of underlying regulations. Methyl jasmonate (MeJA) treatment induces the whole-plant senescence of tobacco in a light-intensity-dependent manner, which is suppressed by silencing of NtCOI1 that encodes the receptor protein of JA-Ile (the bioactive derivative of JA). MeJA treatment could induce the senescence-specific cysteine protease gene SAG12 and another cysteine protease gene SAG-L1 to high expression levels in the detached leaf patches under dark conditions but failed to induce their expression in tobacco whole plants under light conditions. Furthermore, MeJA attenuates the RuBisCo activase (RCA) level in the detached leaves but has no effect on this protein in the whole plant under light conditions. A genome-wide transcriptional assay also supports the presence of a differential regulatory pattern of senescence-related genes during MeJA-induced whole-plant senescence under non-starvation conditions and results in the finding of a chlorophylase activity increase in this process. We also observed that the MeJA-induced senescence of tobacco whole plants is reversible, which is accompanied by a structural change of chloroplasts. This work provides novel insights into JA-induced plant senescence under non-starvation conditions and is helpful to dissect the JA-synchronized process of whole-plant senescence.


Asunto(s)
Ciclopentanos/efectos adversos , Nicotiana/genética , Nicotiana/fisiología , Oxilipinas/efectos adversos , Senescencia de la Planta/efectos de los fármacos , Senescencia de la Planta/genética , Adaptación Ocular/genética , Adaptación Ocular/fisiología , Adaptación a la Oscuridad/genética , Adaptación a la Oscuridad/fisiología , Regulación de la Expresión Génica de las Plantas , Genes de Plantas
19.
Plant Physiol ; 188(1): 151-166, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-34601578

RESUMEN

MYB transcription factors play essential roles in regulating plant secondary metabolism and jasmonate (JA) signaling. Putrescine N-methyltransferase is a key JA-regulated step in the biosynthesis of nicotine, an alkaloidal compound highly accumulated in Nicotiana spp. Here we report the identification of NtMYB305a in tobacco (Nicotiana tabacum) as a regulatory component of nicotine biosynthesis and demonstrate that it binds to the JA-responsive GAG region, which comprises a G-box, an AT-rich motif, and a GCC-box-like element, in the NtPMT1a promoter. Yeast one-hybrid analysis, electrophoretic mobility shift assay and chromatin immunoprecipitation assays showed that NtMYB305a binds to the GAG region in vitro and in vivo. Binding specifically occurs at the ∼30-bp AT-rich motif in a G/C-base-independent manner, thus defining the AT-rich motif as previously unknown MYB-binding element. NtMYB305a localized in the nucleus of tobacco cells where it is capable of activating the expression of a 4×GAG-driven GUS reporter in an AT-rich motif-dependent manner. NtMYB305a positively regulates nicotine biosynthesis and the expression of NtPMT and other nicotine pathway genes. NtMYB305a acts synergistically with NtMYC2a to regulate nicotine biosynthesis, but no interaction between these two proteins was detected. This identification of NtMYB305a provides insights into the regulation of nicotine biosynthesis and extends the roles played by MYB transcription factors in plant secondary metabolism.


Asunto(s)
Metiltransferasas/genética , Metiltransferasas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Nicotina/biosíntesis , Nicotina/genética , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/metabolismo
20.
Polymers (Basel) ; 15(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36616366

RESUMEN

In the context of high-quality development, environmental issues are being paid more and more attention to, and the release of free formaldehyde has become a major problem that needs to be solved. Glueless plywood mainly adopts natural substances as raw materials, without adding chemical products, such as resin adhesives, and it does not contain harmful substances, such as formaldehyde. Glueless plywood is a green product that causes no pollution in the environment and no harm to the human body. In this study, the corresponding weak-phase components in boxwood were pre-delivered by an acidic environmental treatment, and the high-temperature and high-pressure compacting process produced a glueless boxwood panel with excellent water resistance and mechanical properties, while remaining environmentally friendly.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...