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1.
ACS Appl Mater Interfaces ; 16(23): 30371-30384, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38815133

RESUMO

Manganese oxides with porous structure and abundant active sites show potential in degrading sulfur mustard (HD). However, there is an interface effect between the oily liquid HD and nano oxides, and the powder is prone to agglomeration, which leads to incomplete contact and limited degradation ability. Here, we demonstrate a simple hydrothermal method for preparing MnO2/Ti3C2 composites to address this problem. The influence of morphology and crystal structure on performance are examined. Herein, flower-like MnO2 is loaded onto the surface or interlayer of Ti3C2-MXene nanosheets during in situ formation, significantly expanding the specific surface area. It also provides abundant acid-base sites and oxygen vacancies for the degradation of simulants 2-chloro-ethyl-ethyl thioether (2-CEES) without external energy, resulting in a reaction half-life as fast as 12.5 min. The relationship between structure and performance is clearly elaborated through temperature-programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS) analyses. Based on in situ attenuated total reflection-Fourier transform infrared (ATR-FTIR) analysis, gas chromatography-mass spectrometry (GC-MS) analysis, and density functional theory (DFT) calculation, the proposed degradation pathway of the 2-CEES molecule is a synergistic effect of hydrolysis, elimination, and oxidation. Furthermore, the products are nontoxic or low toxic. Metal oxide/MXene composites are first illustrated for their potential use in degrading sulfur mustard, suggesting new insights into these materials as novel decontamination for decomposing chemical warfare agents.

2.
Science ; 383(6689): 1318-1325, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38513014

RESUMO

Plants are constantly exposed to volatile organic compounds (VOCs) that are released during plant-plant communication, within-plant self-signaling, and plant-microbe interactions. Therefore, understanding VOC perception and downstream signaling is vital for unraveling the mechanisms behind information exchange in plants, which remain largely unexplored. Using the hormone-like function of volatile terpenoids in reproductive organ development as a system with a visual marker for communication, we demonstrate that a petunia karrikin-insensitive receptor, PhKAI2ia, stereospecifically perceives the (-)-germacrene D signal, triggering a KAI2-mediated signaling cascade and affecting plant fitness. This study uncovers the role(s) of the intermediate clade of KAI2 receptors, illuminates the involvement of a KAI2ia-dependent signaling pathway in volatile communication, and provides new insights into plant olfaction and the long-standing question about the nature of potential endogenous KAI2 ligand(s).


Assuntos
Furanos , Hidrolases , Petunia , Piranos , Compostos Orgânicos Voláteis , Hidrolases/genética , Hidrolases/metabolismo , Transdução de Sinais , Compostos Orgânicos Voláteis/metabolismo , Petunia/fisiologia , Furanos/metabolismo , Piranos/metabolismo , Sesquiterpenos de Germacrano/metabolismo
3.
New Phytol ; 241(4): 1829-1839, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38058220

RESUMO

The biosynthesis of specialized metabolites is strictly regulated by environmental inputs such as the day-night cycle, but the underlying mechanisms remain elusive. In Petunia hybrida cv. Mitchell flowers, the biosynthesis and emission of volatile compounds display a diurnal pattern with a peak in the evening to attract nocturnal pollinators. Using petunia flowers as a model system, we found that chromatin level regulation, especially histone acetylation, plays an essential role in mediating the day-night oscillation of the biosynthetic gene network of specialized metabolites. By performing time-course chromatin immunoprecipitation assays for histone modifications, we uncovered that a specific group of genes involved in the regulation, biosynthesis, and emission of floral volatile compounds, which displays the greatest magnitude in day-night oscillating gene expression, is associated with highly dynamic histone acetylation marks H3K9ac and H3K27ac. Specifically, the strongest oscillating genes featured a drastic removal of histone acetylation marks at night, potentially to shut down the biosynthesis of floral volatile compounds during the morning when they are not needed. Inhibiting daytime histone acetylation led to a compromised evening induction of these genes. Overall, our study suggested an active role of chromatin modification in the diurnal oscillation of specialized metabolic network.


Assuntos
Histonas , Petunia , Histonas/metabolismo , Acetilação , Redes e Vias Metabólicas , Processamento de Proteína Pós-Traducional , Cromatina/metabolismo , Flores/fisiologia , Petunia/metabolismo , Regulação da Expressão Gênica de Plantas
4.
J Colloid Interface Sci ; 657: 1003-1015, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38141470

RESUMO

Pelargonic acid vanillylamide (PAVA), a capsaicin-type dacryagogue agent utilized for counter-terrorism and riot control, possesses a low stimulus threshold. This characteristic can lead to environmental contamination following its application and may easily result in secondary stimulation to personnel. Cobalt-doped Ti3C2-MXene nanosheets (Co3O4/Ti3C2@C) were synthesized for the purpose of activating peracetic acid (PAA) and degrading PAVA. A carbon layer was coated on the surface of Ti3C2-MXene nanosheets to address the challenge of poor oxygen resistance in MXenes, thus preventing a significant decline in surface reactivity. The BET surface area of Co3O4/Ti3C2@C was expanded to 149.6 m2/g, significantly exceeding that of Ti3C2 (13.0 m2/g) and Co3O4 (56.4 m2/g). With 0.5 mg/mL of Co3O4/Ti3C2@C and 0.35 mM of PAA, 100 mg/L of PAVA was completely degraded within 60 min. The augmented BET surface area and the presence of more active sites confer remarkable PAA activation and catalytic degradation properties toward PAVA. Parameters such as initial pH, PAVA concentration, catalyst dosage, and PAA concentration on PAVA degradation were systematically assessed. Furthermore, the reusability and stability of the nanocomposite were substantiated through recycling tests. Radical quenching experiments and electron paramagnetic resonance analysis demonstrated the acetylperoxy radical (CH3CO3) as the primary species responsible for PAVA degradation. This research serves as an illustration of the utilization of MXene and transition metal activated PAA in wastewater treatment.

5.
Biochem Biophys Res Commun ; 688: 149065, 2023 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-37979398

RESUMO

Intestinal injury caused by traumatic brain injury (TBI) seriously affects patient prognosis; however, the underlying mechanisms are unknown. Recent studies have demonstrated that ferritinophagy-mediated ferroptosis is involved in several intestinal disorders. However, uncertainty persists regarding the role of ferritinophagy-mediated ferroptosis in the intestinal damage caused by TBI. High-throughput transcriptional sequencing was used to identify the genes that were differentially expressed in the intestine after TBI. The intestinal tissues were harvested for hematoxylin and eosin staining (HE), immunofluorescence, and western blot (WB). Lipid peroxide markers and iron content in the intestines were determined using the corresponding kits. High throughput sequencing revealed that the ferroptosis signaling pathway was enriched, demonstrating that intestinal damage caused by TBI may include ferroptosis. Chiu's score, tight junction proteins, and lipid peroxide indicators demonstrated that TBI caused an intestinal mucosal injury that persisted for several days. The ferroptosis pathway-related proteins, ferritin heavy polypeptide 1 (Fth1) and glutathione peroxidase 4 (GPX4), exhibited dynamic changes. The results indicated that lipid peroxide products were markedly increased, whereas antioxidant enzymes were markedly decreased. WB analysis demonstrated that the expression levels of nuclear receptor coactivator 4 (NCOA4), LC3II/LC3I, and p62 were markedly upregulated, whereas those of GPX4 and Fth1 were markedly downregulated. In addition, ferrostatin-1 attenuates intestinal ferroptosis and injury post-TBI in vivo. Intriguingly, 3-methyladenine (3-MA) reduces intestinal ferritin decomposition, iron accumulation, and ferroptosis after TBI. Moreover, 3-MA markedly reduced intestinal apoptosis. In conclusion, NCOA4 mediated ferritinophagy and ferroptosis play roles in intestinal oxidative stress injury post-TBI. This study provides a deeper understanding of the mechanisms underlying intestinal damage following TBI.


Assuntos
Lesões Encefálicas Traumáticas , Ferroptose , Humanos , Peróxidos Lipídicos , Intestinos , Estresse Oxidativo , Fatores de Transcrição , Ferritinas , Ferro , Autofagia , Coativadores de Receptor Nuclear/genética
6.
Hortic Res ; 10(11): uhad194, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023485

RESUMO

Although the functions of WRKY transcription factors in drought resistance are well known, their regulatory mechanisms in response to drought by stabilising photosynthesis remain unclear. Here, a differentially expressed PoWRKY71 gene that was highly expressed in drought-treated Paeonia ostii leaves was identified through transcriptome analysis. PoWRKY71 positively responded to drought stress with significantly enhanced expression patterns and overexpressing PoWRKY71 in tobacco greatly improved plant tolerance to drought stress, whereas silencing PoWRKY71 in P. ostii resulted in a drought-intolerant phenotype. Furthermore, lower chlorophyll contents, photosynthesis, and inhibited expression of photosynthesis-related light-harvesting chlorophyll a/b-binding 151 (CAB151) gene were found in PoWRKY71-silenced P. ostii. Meanwhile, a homologous system indicated that drought treatment increased PoCAB151 promoter activity. Interactive assays revealed that PoWRKY71 directly bound on the W-box element of PoCAB151 promoter and activated its transcription. In addition, PoCAB151 overexpressing plants demonstrated increased drought tolerance, together with significantly higher chlorophyll contents and photosynthesis, whereas these indices were dramatically lower in PoCAB151-silenced P. ostii. The above results indicated that PoWRKY71 activated the expression of PoCAB151, thus stabilising photosynthesis via regulating chloroplast homeostasis and chlorophyll content in P. ostii under drought stress. This study reveals a novel drought-resistance mechanism in plants and provides a feasible strategy for improving plant drought resistance via stabilising photosynthesis.

7.
Curr Biol ; 33(11): R473-R478, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37279678

RESUMO

Environmental factors such as light, water, minerals, temperature, and other organisms affect plant growth and development. Unlike animals, plants can't escape from unfavorable biotic and abiotic stresses. Thus, they evolved the ability to biosynthesize specific chemicals referred to as plant specialized metabolites in order to facilitate successful interactions with the surrounding environment, as well as with other organisms including plants, insects, microorganisms, and animals. While the exact number of plant specialized metabolites, historically called secondary metabolites, is currently unknown, it has been estimated to range from 200,000 to 1,000,000 compounds. In contrast to the species-, organ- and tissue-specific nature of plant specialized metabolites, primary metabolites are shared by all living organisms, are vital for growth, development and reproduction, and comprise only about 8,000 compounds. The biosynthesis and storage of plant specialized metabolites are developmentally and temporally regulated and depend on biotic and abiotic factors. Specific cell types, subcellular organelles, microcompartments, and/or anatomical structures are often devoted to producing and storing these compounds. The functions of many specialized metabolites are still not fully understood but are generally considered to be essential for the fitness and survival of plants, partially by interacting with other organisms in both mutualistic (for example, attraction of pollinators) and antagonistic (such as defense against herbivores and pathogens) ways. In this primer, we will focus on specialized-metabolite functions in plant defense interactions and on the genetic, molecular, and biochemical mechanisms leading to the structural diversity of specialized metabolites. Though less understood, we will also touch on the mode of action of specialized metabolites in plant defense.


Assuntos
Desenvolvimento Vegetal , Plantas , Animais , Plantas/metabolismo
8.
BMC Med ; 21(1): 199, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37254196

RESUMO

BACKGROUND: Contact sports athletes and military personnel who suffered a repetitive mild traumatic brain injury (rmTBI) are at high risk of neurodegenerative diseases such as advanced dementia and chronic traumatic encephalopathy (CTE). However, due to the lack of specific biological indicators in clinical practice, the diagnosis and treatment of rmTBI are quite limited. METHODS: We used 2-methacryloyloxyethyl phosphorylcholine (MPC)-nanocapsules to deliver immunoglobulins (IgG), which can increase the delivery efficiency and specific target of IgG while reducing the effective therapeutic dose of the drug. RESULTS: Our results demonstrated that MPC-capsuled immunoglobulins (MPC-n (IgG)) significantly alleviated cognitive impairment, hippocampal atrophy, p-Tau deposition, and myelin injury in rmTBI mice compared with free IgG. Furthermore, MPC-n (IgG) can also effectively inhibit the activation of microglia and the release of inflammatory factors. CONCLUSIONS: In the present study, we put forward an efficient strategy for the treatment of rmTBI-related cognitive impairment and provide evidence for the administration of low-dose IgG.


Assuntos
Concussão Encefálica , Disfunção Cognitiva , Doenças Neurodegenerativas , Camundongos , Animais , Concussão Encefálica/complicações , Concussão Encefálica/tratamento farmacológico , Concussão Encefálica/psicologia , Modelos Animais de Doenças , Disfunção Cognitiva/tratamento farmacológico , Imunoglobulina G , Encéfalo
9.
Proc Natl Acad Sci U S A ; 120(19): e2221440120, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37126706

RESUMO

Geraniol derived from essential oils of various plant species is widely used in the cosmetic and perfume industries. It is also an essential trait of the pleasant smell of rose flowers. In contrast to other monoterpenes which are produced in plastids via the methyl erythritol phosphate pathway, geraniol biosynthesis in roses relies on cytosolic NUDX1 hydrolase which dephosphorylates geranyl diphosphate (GPP). However, the metabolic origin of cytosolic GPP remains unknown. By feeding Rosa chinensis "Old Blush" flowers with pathway-specific precursors and inhibitors, combined with metabolic profiling and functional characterization of enzymes in vitro and in planta, we show that geraniol is synthesized through the cytosolic mevalonate (MVA) pathway by a bifunctional geranyl/farnesyl diphosphate synthase, RcG/FPPS1, producing both GPP and farnesyl diphosphate (FPP). The downregulation and overexpression of RcG/FPPS1 in rose petals affected not only geraniol and germacrene D emissions but also dihydro-ß-ionol, the latter due to metabolic cross talk of RcG/FPPS1-dependent isoprenoid intermediates trafficking from the cytosol to plastids. Phylogenetic analysis together with functional characterization of G/FPPS orthologs revealed that the G/FPPS activity is conserved among Rosaceae species. Site-directed mutagenesis and molecular dynamic simulations enabled to identify two conserved amino acids that evolved from ancestral FPPSs and contribute to GPP/FPP product specificity. Overall, this study elucidates the origin of the cytosolic GPP for NUDX1-dependent geraniol production, provides insights into the emergence of the RcG/FPPS1 GPPS activity from the ancestral FPPSs, and shows that RcG/FPPS1 plays a key role in the biosynthesis of volatile terpenoid compounds in rose flowers.


Assuntos
Geraniltranstransferase , Rosa , Geraniltranstransferase/genética , Ácido Mevalônico/metabolismo , Rosa/metabolismo , Citosol/metabolismo , Filogenia , Terpenos/metabolismo , Flores/metabolismo
10.
Nat Commun ; 14(1): 330, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658137

RESUMO

For volatile organic compounds (VOCs) to be released from the plant cell into the atmosphere, they have to cross the plasma membrane, the cell wall, and the cuticle. However, how these hydrophobic compounds cross the hydrophilic cell wall is largely unknown. Using biochemical and reverse-genetic approaches combined with mathematical simulation, we show that cell-wall localized non-specific lipid transfer proteins (nsLTPs) facilitate VOC emission. Out of three highly expressed nsLTPs in petunia petals, which emit high levels of phenylpropanoid/benzenoid compounds, only PhnsLTP3 contributes to the VOC export across the cell wall to the cuticle. A decrease in PhnsLTP3 expression reduces volatile emission and leads to VOC redistribution with less VOCs reaching the cuticle without affecting their total pools. This intracellular build-up of VOCs lowers their biosynthesis by feedback downregulation of phenylalanine precursor supply to prevent self-intoxication. Overall, these results demonstrate that nsLTPs are intrinsic members of the VOC emission network, which facilitate VOC diffusion across the cell wall.


Assuntos
Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/metabolismo , Difusão , Fenilalanina , Parede Celular/metabolismo , Lipídeos
11.
Plant Physiol ; 191(1): 428-445, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36305685

RESUMO

Stem bending or lodging caused by insufficient stem strength is an important limiting factor for plant production. Secondary cell walls play a crucial role in plant stem strength, but whether WRKY transcription factors can positively modulate secondary cell wall thickness are remain unknown. Here, we characterized a WRKY transcription factor PlWRKY41a from herbaceous peony (Paeonia lactiflora), which was highly expressed in stems. PlWRKY41a functioned as a nucleus-localized transcriptional activator and enhanced stem strength by positively modulating secondary cell wall thickness. Moreover, PlWRKY41a bound to the promoter of the XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE4 (PlXTH4) and activated the expression of PlXTH4. PlXTH4-overexpressing tobacco (Nicotiana tabacum) had thicker secondary cell walls, resulting in enhanced stem strength, while PlXTH4-silenced P. lactiflora had thinner secondary cell walls, showing decreased stem strength. Additionally, PlWRKY41a directly interacted with PlMYB43 to form a protein complex, and their interaction induced the expression of PlXTH4. These data support that the PlMYB43-PlWRKY41a protein complex can directly activate the expression of PlXTH4 to enhance stem strength by modulating secondary cell wall thickness in P. lactiflora. The results will enhance our understanding of the formation mechanism of stem strength and provide a candidate gene to improve stem straightness in plants.


Assuntos
Paeonia , Paeonia/genética , Paeonia/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Parede Celular/metabolismo , Plantas/metabolismo
12.
Am J Cancer Res ; 12(10): 4545-4565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36381320

RESUMO

Cuproptosis, a newly discovered mechanism of programmed cell death, is important for detailing the metabolic aspects of cancer progression and thereby guiding cancer therapy. An exciting era of translational medicine has led to the rapid development of countless immunotherapeutic strategies. The existing successful cancer immunotherapies have sparked new hope for patients with solid and hematologic malignancies. Hence, it is important to characterize the link between the cuproptosis process and the immunity status in the tumor microenvironment (TME) in Lung Adenocarcinoma (LUAD), which may be able to predict patient's prognosis. In this study, we systematically assessed 10 cuproptosis-associated genes (CAGs) and comprehensively characterized the relationship between cuproptosis and the molecular characteristics and immune cell infiltration of tumor tissue, prognosis and clinical treatment of patients. Subsequently, the CAG_score for predicting overall survival (OS) was established and its reliable predictive ability in LUAD patients was confirmed. Next, we created a highly reliable nomogram to facilitate the clinical viability of the CAG_score. The low CAG_score group, with lower immune cell infiltration, and mutation burden, had a significantly superior OS, which was associated with a better response to immunotherapy. The present study revealed that cuproptosis play a significant role in TME regulation in LUAD. Collectively, we identified a prognostic CAGs-related signature for LUAD patients. This signature may contribute to clarifying the characteristics of TME and enable the exploration of more potent immunotherapy strategies.

13.
Front Immunol ; 13: 954848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35898498

RESUMO

Rheumatoid arthritis (RA) is a chronic, heterogeneous autoimmune disease. Its high disability rate has a serious impact on society and individuals, but there is still a lack of effective and reliable diagnostic markers and therapeutic targets for RA. In this study, we integrated RA patient information from three GEO databases for differential gene expression analysis. Additionally, we also obtained pan-cancer-related genes from the TCGA and GTEx databases. For RA-related differential genes, we performed functional enrichment analysis and constructed a weighted gene co-expression network (WGCNA). Then, we obtained 490 key genes by intersecting the significant module genes selected by WGCNA and the differential genes. After using the RanddomForest, SVM-REF, and LASSO three algorithms to analyze these key genes and take the intersection, based on the four core genes (BTN3A2, CYFIP2, ST8SIA1, and TYMS) that we found, we constructed an RA diagnosis. The nomogram model showed good reliability and validity after evaluation, and the ROC curves of the four genes showed that these four genes played an important role in the pathogenesis of RA. After further gene correlation analysis, immune infiltration analysis, and mouse gene expression validation, we finally selected CYFIP2 as the cut-in gene for pan-cancer analysis. The results of the pan-cancer analysis showed that CYFIP2 was closely related to the prognosis of patients with various tumors, the degree of immune cell infiltration, as well as TMB, MSI, and other indicators, suggesting that this gene may be a potential intervention target for human diseases including RA and tumors.


Assuntos
Artrite Reumatoide , Neoplasias , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Artrite Reumatoide/tratamento farmacológico , Redes Reguladoras de Genes , Humanos , Imunidade Inata , Camundongos , Neoplasias/complicações , Neoplasias/genética , Reprodutibilidade dos Testes
14.
Front Genet ; 13: 909797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754800

RESUMO

Lung adenocarcinoma is increasingly harmful to society and individuals as cancer with an inferior prognosis and insensitive to chemotherapy. Previous studies have demonstrated that oxidative stress and lncRNAs play a vital role in many biological processes. Therefore, we explored the role of lncRNAs associated with oxidative stress in the prognosis and survival of LUAD patients. We examined the expression profiles of lncRNAs and oxidative stress genes in this study. A prognosis prediction model and a nomogram were built based on oxidative stress-related lncRNAs. Functional and drug sensitivity analyses were also performed depending on oxidative stress-related lncRNA signature. Moreover, we investigated the relationship between immune response and immunotherapy. The results showed that a risk scoring model based on 16 critical oxidative stress lncRNAs was able to distinguish the clinical status of LUAD and better predict the prognosis and survival. Additionally, the model demonstrated a close correlation with the tumor immune system, and these key lncRNAs also revealed the relationship between LUAD and chemotherapeutic drug sensitivity. Our work aims to provide new perspectives and new ideas for the treatment and management of LUAD.

15.
Plant Biotechnol J ; 20(9): 1770-1785, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35633313

RESUMO

After polyploidization originated from one interspecific hybridization event in Gossypium, Gossypium barbadense evolved to produce extra-long staple fibres than Gossypium hirsutum (Upland cotton), which produces a higher fibre yield. The genomic diversity between G. barbadense and G. hirsutum thus provides a genetic basis for fibre trait variation. Recently, rapid accumulation of gene disruption or deleterious mutation was reported in allotetraploid cotton genomes, with unknown impacts on fibre traits. Here, we identified gene disruptions in allotetraploid G. hirsutum (18.14%) and G. barbadense (17.38%) through comparison with their presumed diploid progenitors. Relative to conserved genes, these disrupted genes exhibited faster evolution rate, lower expression level and altered gene co-expression networks. Within a module regulating fibre elongation, a hub gene experienced gene disruption in G. hirsutum after polyploidization, with a 2-bp deletion in the coding region of GhNPLA1D introducing early termination of translation. This deletion was observed in all of the 34 G. hirsutum landraces and 36 G. hirsutum cultivars, but not in 96% of 57 G. barbadense accessions. Retrieving the disrupted gene GhNPLA1D using its homoeolog GhNPLA1A achieved longer fibre length in G. hirsutum. Further enzyme activity and lipids analysis confirmed that GhNPLA1A encodes a typical phospholipase A and promotes cotton fibre elongation via elevating intracellular levels of linolenic acid and 34:3 phosphatidylinositol. Our work opens a strategy for identifying disrupted genes and retrieving their functions in ways that can provide valuable resources for accelerating fibre trait enhancement in cotton breeding.


Assuntos
Fibra de Algodão , Melhoramento Vegetal , Genes de Plantas/genética , Gossypium/genética , Fosfolipases/genética
16.
J Exp Bot ; 73(17): 5974-5991, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35436332

RESUMO

Cut flower quality is severely restrained by stem bending due to low stem strength. Melatonin has been shown to function in many aspects of plant growth and development, yet whether it can enhance stem strength, and the corresponding underlying mechanisms remain unclear. We investigated the role of melatonin in enhancement of stem strength in herbaceous peony (Paeonia lactiflora Pall.) by applying exogenous melatonin and changing endogenous melatonin biosynthesis. Endogenous melatonin content positively correlated with lignin content and stem strength in various P. lactiflora cultivars. Supplementation with exogenous melatonin significantly enhanced stem strength by increasing lignin content and the S/G lignin compositional ratio, up-regulating lignin biosynthetic gene expression. Moreover, overexpression of TRYPTOPHAN DECARBOXYLASE GENE (TDC) responsible for the first committed step of melatonin biosynthesis in tobacco, significantly increased endogenous melatonin, which further increased the S/G ratio and stem strength. In contrast, silencing PlTDC in P. lactiflora decreased endogenous melatonin, the S/G ratio and stem strength. Finally, manipulating the expression of CAFFEIC ACID O-METHYLTRANSFERASE GENE (COMT1), which is involved in both melatonin and lignin biosynthesis, showed even greater effects on melatonin, the S/G ratio and stem strength. Our results suggest that melatonin has a positive regulatory effect on P. lactiflora stem strength.


Assuntos
Melatonina , Paeonia , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Melatonina/metabolismo , Paeonia/metabolismo , Plantas/metabolismo
17.
Nat Commun ; 13(1): 1352, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292635

RESUMO

Benzaldehyde, the simplest aromatic aldehyde, is one of the most wide-spread volatiles that serves as a pollinator attractant, flavor, and antifungal compound. However, the enzyme responsible for its formation in plants remains unknown. Using a combination of in vivo stable isotope labeling, classical biochemical, proteomics and genetic approaches, we show that in petunia benzaldehyde is synthesized via the ß-oxidative pathway in peroxisomes by a heterodimeric enzyme consisting of α and ß subunits, which belong to the NAD(P)-binding Rossmann-fold superfamily. Both subunits are alone catalytically inactive but, when mixed in equal amounts, form an active enzyme, which exhibits strict substrate specificity towards benzoyl-CoA and uses NADPH as a cofactor. Alpha subunits can form functional heterodimers with phylogenetically distant ß subunits, but not all ß subunits partner with α subunits, at least in Arabidopsis. Analysis of spatial, developmental and rhythmic expression of genes encoding α and ß subunits revealed that expression of the gene for the α subunit likely plays a key role in regulating benzaldehyde biosynthesis.


Assuntos
Arabidopsis , Petunia , Benzaldeídos , Peroxissomos/metabolismo , Petunia/genética , Petunia/metabolismo , Plantas
18.
J Exp Bot ; 73(2): 555-570, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34129033

RESUMO

Galling insects gain food and shelter by inducing specialized anatomical structures in their plant hosts. Such galls often accumulate plant defensive metabolites protecting the inhabiting insects from predation. We previously found that, despite a marked natural chemopolymorphism in natural populations of Pistacia palaestina, the monoterpene content in Baizongia pistaciae-induced galls is substantially higher than in leaves of their hosts. Here we show a general up-regulation of key structural genes in both the plastidial and cytosolic terpene biosynthetic pathways in galls as compared with non-colonized leaves. Novel prenyltransferases and terpene synthases were functionally expressed in Escherichia coli to reveal their biochemical function. Individual Pistacia trees exhibiting chemopolymorphism in terpene compositions displayed differential up-regulation of selected terpene synthase genes, and the metabolites generated by their gene products in vitro corresponded to the monoterpenes accumulated by each tree. Our results delineate molecular mechanisms responsible for the formation of enhanced monoterpene in galls and the observed intraspecific monoterpene chemodiversity displayed in P. palaestina. We demonstrate that gall-inhabiting aphids transcriptionally reprogram their host terpene pathways by up-regulating tree-specific genes, boosting the accumulation of plant defensive compounds for the protection of colonizing insects.


Assuntos
Afídeos , Pistacia , Animais , Tumores de Planta , Terpenos , Regulação para Cima
19.
Front Psychol ; 13: 1077614, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687831

RESUMO

Introduction: Industry-university-research cooperation innovation, which is often characterized by resource complementarity and the sharing technology, has become one of the most preferred innovation cooperation methods for enterprises. However, various problems still occur in the process of industry-university-research cooperations, such as poor innovation performance and difficulty in sustaining cooperation. Existing studies mostly focus on the macroscopic perspectives of geographic location, cooperation scale, concentration, and diversification of industry-university-research cooperation subjects, and fail to explore the microscopic behavioral mechanisms. Methods: Therefore, this paper establishes the interactive behavior of industry-university-research subjects and defines its concepts and dimensions in an attempt to provide a mechanism for improving the cooperative innovation performance of industry-university-research from the micro-behavioral perspective. On the basis of theoretical analysis, this paper develops a model of the relationship between cooperative trust, cooperative communication, and cooperative innovation performance for interactive behavior, while exploring the mediating role of knowledge absorptive capacity. The model was validated by stepwise regression using data from 325 questionnaires. Results: The paper found that cooperative trust and cooperative communication in the cooperative interactive behavior of industry-university-research positively contribute to the improvement of cooperative innovation performance. Knowledge absorptive capacity plays a partially mediating role between the interactive behaviors and cooperative innovation performance. More specifically, knowledge absorptive capacity partially mediates cooperative communication in cooperative innovation performance and completely mediates cooperative trust in cooperative innovation performance. The results are largely consistent with the results of the heterogeneity analysis of the sample. Discussion: This paper not only explains why the cooperative innovation performance of industry-university-research is poor from the perspective of interactive behavior, but also enriches the research perspective of industry-university-research and provides theoretical support for enterprises to optimize the relationship between industry, university, and research institutes.

20.
Int J Mol Sci ; 22(21)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34768794

RESUMO

Chloroplasts are semi-autonomous organelles governed by the precise coordination between the genomes of their own and the nucleus for functioning correctly in response to developmental and environmental cues. Under stressed conditions, various plastid-to-nucleus retrograde signals are generated to regulate the expression of a large number of nuclear genes for acclimation. Among these retrograde signaling pathways, the chloroplast protein GENOMES UNCOUPLED 1 (GUN1) is the first component identified. However, in addition to integrating aberrant physiological signals when chloroplasts are challenged by stresses such as photooxidative damage or the inhibition of plastid gene expression, GUN1 was also found to regulate other developmental processes such as flowering. Several partner proteins have been found to interact with GUN1 and facilitate its different regulatory functions. In this study, we report 15 possible interacting proteins identified through yeast two-hybrid (Y2H) screening, among which 11 showed positive interactions by pair-wise Y2H assay. Through the bimolecular fluorescence complementation assay in Arabidopsis protoplasts, two candidate proteins with chloroplast localization, DJC31 and HCF145, were confirmed to interact with GUN1 in planta. Genes for these GUN1-interacting proteins showed different fluctuations in the WT and gun1 mutant under norflurazon and lincomycin treatments. Our results provide novel clues for a better understanding of molecular mechanisms underlying GUN1-mediated regulations.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Comunicação Celular/genética , Núcleo Celular/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Proteínas de Ligação a DNA/genética , Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/genética , Plastídeos/genética , Mapeamento de Interação de Proteínas/métodos , Mapas de Interação de Proteínas/genética , Mapas de Interação de Proteínas/fisiologia , Transdução de Sinais/genética
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