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1.
Physiol Plant ; 176(2): e14265, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556740

RESUMO

Plant species distribution across ecosystems is influenced by multiple environmental factors, and recurrent seasonal stress events can act as natural selection agents for specific plant traits and limit species distribution. For that, studies aiming at understanding how environmental constraints affect adaptive mechanisms of taxonomically closely related species are of great interest. We chose two Scabiosa species inhabiting contrasting environments: the coastal scabious S. atropurpurea, typically coping with hot-dry summers in a Mediterranean climate, and the mountain scabious S. columbaria facing cold winters in an oceanic climate. A set of functional traits was examined to assess plant performance in these congeneric species from contrasting natural habitats. Both S. atropurpurea and S. columbaria appeared to be perfectly adapted to their environment in terms of adjustments in stomatal closure, CO2 assimilation rate and water use efficiency over the seasons. However, an unexpected dry period during winter followed by the typical Mediterranean hot-dry summer forced S. atropurpurea plants to deploy a set of photoprotective responses during summer. Aside from reductions in leaf water content and Fv/Fm, photoprotective molecules (carotenoids, α-tocopherol and anthocyanins) per unit of chlorophyll increased, mostly as a consequence of a severe chlorophyll loss. The profiling of stress-related hormones (ABA, salicylic acid and jasmonates) revealed associations between ABA and the bioactive jasmonoyl-isoleucine with the underlying photoprotective response to recurrent seasonal stress in S. atropurpurea. We conclude that jasmonates may be used together with ABA as a functional trait that may, at least in part, help understand plant responses to recurrent seasonal stress in the current frame of global climate change.


Assuntos
Antocianinas , Ciclopentanos , Ecossistema , Oxilipinas , Estações do Ano , Clorofila , Folhas de Planta/fisiologia , Água
2.
Physiol Plant ; 176(2): e14250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38467566

RESUMO

The necrotrophic fungus Seiridium cardinale is the main responsible for Cypress Canker Disease (CCD), a pandemic affecting many Cupressaceae worldwide. The present study aims to elucidate the signalling of the early responses in the bark and foliage of CCD-susceptible and -resistant C. sempervirens clones to S. cardinale inoculation (SI and RI, respectively). In the bark of SI, a peaking production of ethylene (Et) and jasmonic acid (JA) occurred at 3 and 4 days post inoculation (dpi), respectively, suggesting an attempted plant response to the pathogen. A response that, however, was ineffective, as confirmed by the severe accumulation of malondialdehyde by-products at 13 dpi (i.e., lipid peroxidation). Differently, Et emission peaked in RI bark at 3 and 13 dpi, whereas abscisic acid (ABA) accumulated at 1, 4 and 13 dpi, resulting in a lower MDA accumulation (and unchanged levels of antioxidant capacity). In the foliage of SI, Et was produced at 1 and 9 dpi, whereas JA and salicylic acid (SA) accumulated at 1 and 3 dpi. Conversely, an increase of ABA and SA occurred at 1 dpi in the RI foliage. This outcome indicates that some of the observed metabolic alterations, mainly occurring as local defence mechanisms, might be able to gradually shift to a systemic resistance, although an accumulation of MDA was observed in both SI and RI foliage (but with an increased antioxidant capacity reported only in the resistant clone). We believe that the results reported here will be useful for the selection of clones able to limit the spread and damage of CCD.


Assuntos
Ascomicetos , Cupressus , Etilenos , Cupressus/metabolismo , Cupressus/microbiologia , Antioxidantes , Casca de Planta/metabolismo , Ácido Abscísico/metabolismo , Ácido Salicílico/metabolismo , Doenças das Plantas/microbiologia , Ciclopentanos/metabolismo , Oxilipinas/metabolismo
3.
BMC Genomics ; 25(1): 254, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448814

RESUMO

BACKGROUND: Neddylation, an important post-translational modification (PTM) of proteins, plays a crucial role in follicular development. MLN4924 is a small-molecule inhibitor of the neddylation-activating enzyme (NAE) that regulates various biological processes. However, the regulatory mechanisms of neddylation in rabbit ovarian cells have not been emphasized. Here, the transcriptome and metabolome profiles in granulosa cells (GCs) treated with MLN4924 were utilized to identify differentially expressed genes, followed by pathway analysis to precisely define the altered metabolisms. RESULTS: The results showed that 563 upregulated and 910 downregulated differentially expressed genes (DEGs) were mainly enriched in pathways related to cancer, cell cycle, PI3K-AKT, progesterone-mediated oocyte maturation, and PPAR signaling pathway. Furthermore, we characterized that MLN4924 inhibits PPAR-mediated lipid metabolism, and disrupts the cell cycle by promoting the apoptosis and proliferation of GCs. Importantly, we found the reduction of several metabolites in the MLN4924 treated GCs, including glycerophosphocholine, arachidic acid, and palmitic acid, which was consistent with the deregulation of PPAR signaling pathways. Furthermore, the increased metabolites included 6-Deoxy-6-sulfo-D-glucono-1,5-lactone and N-Acetyl-D-glucosaminyldiphosphodolichol. Combined with transcriptome data analyses, we identified genes that strongly correlate with metabolic dysregulation, particularly those related to glucose and lipid metabolism. Therefore, neddylation inhibition may disrupt the energy metabolism of GCs. CONCLUSIONS: These results provide a foundation for in-depth research into the role and molecular mechanism of neddylation in ovary development.


Assuntos
Ciclopentanos , Receptores Ativados por Proliferador de Peroxissomo , Fosfatidilinositol 3-Quinases , Pirimidinas , Feminino , Animais , Coelhos , Células da Granulosa , Metabolismo dos Lipídeos
4.
Theor Appl Genet ; 137(3): 72, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446239

RESUMO

KEY MESSAGE: SbMYC2 functions as a key regulator under JA signaling in enhancing drought tolerance of sorghum through direct activating SbGR1. Drought stress is one of the major threats to crop yield. In response to drought stress, functions of basic helix-loop-helix (bHLH) transcription factors (TFs) have been reported in Arabidopsis and rice, but little is known for sorghum. Here, we characterized the function of SbMYC2, a bHLH TF in sorghum, and found that SbMYC2 responded most significantly to PEG-simulated drought stress and JA treatments. Overexpression of SbMYC2 significantly enhanced drought tolerance in Arabidopsis, rice and sorghum. In addition, it reduced reactive oxygen species (ROS) accumulation and increased chlorophyll content in sorghum leaves. While silencing SbMYC2 by virus-induced gene silencing (VIGS) resulted in compromised drought tolerance of sorghum seedlings. Moreover, SbMYC2 can directly activate the expression of GLUTATHIONE-DISULFIDE REDUCTASE gene SbGR1. SbGR1 silencing led to significantly weakened drought tolerance of sorghum, and higher ROS accumulation and lower chlorophyll content in sorghum leaves were detected. In addition, SbMYC2 can interact with SbJAZs, suppressors of JA signaling, and thus can mediate JA signaling to activate SbGR1, thereby regulating sorghum's tolerance to drought stress. Overall, our findings demonstrate that bHLH TF SbMYC2 plays an important role in sorghum's response to drought stress, thus providing one theoretical basis for genetic enhancement of sorghum and even rice.


Assuntos
Arabidopsis , Ciclopentanos , Oryza , Oxilipinas , Sorghum , Resistência à Seca , Sorghum/genética , Espécies Reativas de Oxigênio , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Clorofila , Grão Comestível , Oryza/genética
5.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473801

RESUMO

Epidermal cells are the main avenue for signal and material exchange between plants and the environment. Leaf epidermal cells primarily include pavement cells, guard cells, and trichome cells. The development and distribution of different epidermal cells are tightly regulated by a complex transcriptional regulatory network mediated by phytohormones, including jasmonic acid, and transcription factors. How the fate of leaf epidermal cells is determined, however, is still largely unknown due to the diversity of cell types and the complexity of their regulation. Here, we characterized the transcriptional profiles of epidermal cells in 3-day-old true leaves of Arabidopsis thaliana using single-cell RNA sequencing. We identified two genes encoding BASIC LEUCINE-ZIPPER (bZIP) transcription factors, namely bZIP25 and bZIP53, which are highly expressed in pavement cells and early-stage meristemoid cells. Densities of pavement cells and trichome cells were found to increase and decrease, respectively, in bzip25 and bzip53 mutants, compared with wild-type plants. This trend was more pronounced in the presence of jasmonic acid, suggesting that these transcription factors regulate the development of trichome cells and pavement cells in response to jasmonic acid.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ciclopentanos , Oxilipinas , Fatores de Transcrição de Zíper de Leucina Básica , Células Epidérmicas , Fatores de Transcrição , Folhas de Planta , Tricomas , Análise de Sequência de RNA , Regulação da Expressão Gênica de Plantas
6.
Int J Mol Sci ; 25(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38473825

RESUMO

Flower color is an important trait for the ornamental value of colored rapeseed (Brassica napus L.), as the plant is becoming more popular. However, the color fading of red petals of rapeseed is a problem for its utilization. Unfortunately, the mechanism for the process of color fading in rapeseed is unknown. In the current study, a red flower line, Zhehuhong, was used as plant material to analyze the alterations in its morphological and physiological characteristics, including pigment and phytohormone content, 2 d before flowering (T1), at flowering (T2), and 2 d after flowering (T3). Further, metabolomics and transcriptomics analyses were also performed to reveal the molecular regulation of petal fading. The results show that epidermal cells changed from spherical and tightly arranged to totally collapsed from T1 to T3, according to both paraffin section and scanning electron microscope observation. The pH value and all pigment content except flavonoids decreased significantly during petal fading. The anthocyanin content was reduced by 60.3% at T3 compared to T1. The content of three phytohormones, 1-aminocyclopropanecarboxylic acid, melatonin, and salicylic acid, increased significantly by 2.2, 1.1, and 30.3 times, respectively, from T1 to T3. However, auxin, abscisic acid, and jasmonic acid content decreased from T1 to T3. The result of metabolomics analysis shows that the content of six detected anthocyanin components (cyanidin, peonidin, pelargonidin, delphinidin, petunidin, and malvidin) and their derivatives mainly exhibited a decreasing trend, which was in accordance with the trend of decreasing anthocyanin. Transcriptomics analysis showed downregulation of genes involved in flavonol, flavonoid, and anthocyanin biosynthesis. Furthermore, genes regulating anthocyanin biosynthesis were preferentially expressed at early stages, indicating that the degradation of anthocyanin is the main issue during color fading. The corresponding gene-encoding phytohormone biosynthesis and signaling, JASMONATE-ZIM-DOMAIN PROTEIN, was deactivated to repress anthocyanin biosynthesis, resulting in fading petal color. The results clearly suggest that anthocyanin degradation and phytohormone regulation play essential roles in petal color fading in rapeseed, which is a useful insight for the breeding of colored rapeseed.


Assuntos
Brassica napus , Brassica rapa , Ciclopentanos , Oxilipinas , Reguladores de Crescimento de Plantas , Antocianinas , Multiômica , Melhoramento Vegetal , Flavonoides , Flores , Regulação da Expressão Gênica de Plantas , Cor
7.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473957

RESUMO

Chlorogenic acids (CGAs) are bioactive compounds widely used in the food, pharmaceutical, and cosmetic industries. Carthamus tinctorius is an important economic crop, and its suspension cells are rich in CGAs. However, little is known about the biosynthesis and regulation of CGAs in Carthamus tinctorius cells. This study first elucidated the regulatory mechanism of CGA biosynthesis in methyl jasmonate (MeJA)-treated Carthamus tinctorius cells and the role of the MeJA-responsive hydroxycinnamoyl transferase (HCT) gene in enhancing their CGA accumulation. Firstly, temporal changes in intracellular metabolites showed that MeJA increased the intracellular CGA content up to 1.61-fold to 100.23 mg·g-1. Meanwhile, 31 primary metabolites showed significant differences, with 6 precursors related to increasing CGA biosynthesis. Secondly, the transcriptome data revealed 3637 new genes previously unannotated in the Carthamus tinctorius genome and 3653 differentially expressed genes. The genes involved in the plant signaling pathway and the biosynthesis of CGAs and their precursors showed a general up-regulation, especially the HCT gene family, which ultimately promoted CGA biosynthesis. Thirdly, the expression of a newly annotated and MeJA-responsive HCT gene (CtHCT, CtNewGene_3476) was demonstrated to be positively correlated with CGA accumulation in the cells, and transient overexpression of CtHCT enhanced CGA accumulation in tobacco. Finally, in vitro catalysis kinetics and molecular docking simulations revealed the ability and mechanism of the CtHCT protein to bind to various substrates and catalyze the formation of four hydroxycinnamic esters, including CGAs. These findings strengthened our understanding of the regulatory mechanism of CGA biosynthesis, thereby providing theoretical support for the efficient production of CGAs.


Assuntos
Acetatos , Carthamus tinctorius , Ciclopentanos , Oxilipinas , Transferases , Transferases/metabolismo , Ácido Clorogênico/metabolismo , Carthamus tinctorius/genética , Simulação de Acoplamento Molecular , Transcriptoma , Nucleotidiltransferases/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Nat Commun ; 15(1): 2262, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480732

RESUMO

The inter-subspecific indica-japonica hybrid rice confer potential higher yield than the widely used indica-indica intra-subspecific hybrid rice. Nevertheless, the utilization of this strong heterosis is currently hindered by asynchronous diurnal floret opening time (DFOT) of indica and japonica parental lines. Here, we identify OsMYB8 as a key regulator of rice DFOT. OsMYB8 induces the transcription of JA-Ile synthetase OsJAR1, thereby regulating the expression of genes related to cell osmolality and cell wall remodeling in lodicules to promote floret opening. Natural variations of OsMYB8 promoter contribute to its differential expression, thus differential transcription of OsJAR1 and accumulation of JA-Ile in lodicules of indica and japonica subspecies. Furthermore, introgression of the indica haplotype of OsMYB8 into japonica effectively promotes DFOT in japonica. Our findings reveal an OsMYB8-OsJAR1 module that regulates differential DFOT in indica and japonica, and provide a strategy for breeding early DFOT japonica to facilitate breeding of indica-japonica hybrids.


Assuntos
Genes de Plantas , Isoleucina/análogos & derivados , Oryza , Melhoramento Vegetal , Vigor Híbrido , Ciclopentanos/metabolismo , Oryza/metabolismo
9.
Physiol Plant ; 176(2): e14257, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38504376

RESUMO

The plant hormone jasmonic acid (JA) is a signalling compound involved in the regulation of cellular defence and development in plants. In this study, we investigated the roles of a JA-responsive MYB transcription factor, JMTF1, in the JA-regulated defence response against rice bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo). JMTF1 did not interact with any JASMONATE ZIM-domain (JAZ) proteins. Transgenic rice plants overexpressing JMTF1 showed a JA-hypersensitive phenotype and enhanced resistance against Xoo. JMTF1 upregulated the expression of a peroxidase, OsPrx26, and monoterpene synthase, OsTPS24, which are involved in the biosynthesis of lignin and antibacterial monoterpene, γ-terpinene, respectively. OsPrx26 was mainly expressed in the vascular bundle. Transgenic rice plants overexpressing OsPrx26 showed enhanced resistance against Xoo. In addition to the JA-hypersensitive phenotype, the JMTF1-overexpressing rice plants showed a typical auxin-related phenotype. The leaf divergence and shoot gravitropic responses were defective, and the number of lateral roots decreased significantly in the JMTF1-overexpressing rice plants. JMTF1 downregulated the expression of auxin-responsive genes but upregulated the expression of OsIAA13, a suppressor of auxin signalling. The rice gain-of-function mutant Osiaa13 showed high resistance against Xoo. Transgenic rice plants overexpressing OsEXPA4, a JMTF1-downregulated auxin-responsive gene, showed increased susceptibility to Xoo. JMTF1 is selectively bound to the promoter of OsPrx26 in vivo. These results suggest that JMTF1 positively regulates disease resistance against Xoo by coordinating crosstalk between JA- and auxin-signalling in rice.


Assuntos
Oryza , Xanthomonas , Oryza/metabolismo , Transdução de Sinais/genética , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Resistência à Doença/genética , Ácidos Indolacéticos/metabolismo , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Physiol Plant ; 176(2): e14260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511471

RESUMO

Bacosides are dammarane-type triterpenoidal saponins in Bacopa monnieri and have various pharmacological applications. All the bacosides are diversified from two isomers, i.e., jujubogenin and pseudojujubogenin. The biosynthetic pathway of bacoside is not well elucidated. In the present study, we characterized a UDP-glycosyltransferase, UGT79A18, involved in the glycosylation of pseudojujubogenin. UGT79A18 shows higher expression in response to 5 h of wounding, and 3 h of MeJA treatment. The recombinant UGT79A18 shows in vitro activity against a wide range of flavonoids and triterpenes and has a substrate preference for protopanaxadiol, a dammarane-type triterpene. Secondary metabolite analysis of overexpression and knockdown lines of UGT79A18 in B. monnieri identify bacopasaponin D, bacopaside II, bacopaside N2 and pseudojujubogenin glucosyl rhamnoside as the major bacosides that were differentially accumulated. In the overexpression lines of UGT79A18, we found 1.7-fold enhanced bacopaside II, 8-fold enhanced bacopasaponin D, 3-fold enhanced pseudojujubogenin glucosyl rhamnoside, and 1.6-fold enhanced bacopaside N2 content in comparison with vector control plant, whereas in the knockdown lines of UGT79A18, we found 1.4-fold reduction in bacopaside II content, 3-fold reduction in the bacopasaponin D content, 2-fold reduction in the pseudojujubogenin glucosyl rhamnoside content, and 1.5-fold reduction in bacopaside N2 content in comparison with vector control. These results suggest that UGT79A18 is a significant UDP glycosyltransferase involved in glycosylating pseudojujubogenin and enhancing the pseudojujubogenin-derived bacosides.


Assuntos
Acetatos , Bacopa , Ciclopentanos , Oxilipinas , Saponinas , Triterpenos , Bacopa/genética , Bacopa/química , Glicosiltransferases/genética , Vias Biossintéticas , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Difosfato de Uridina , Extratos Vegetais/química
11.
Mar Drugs ; 22(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38535456

RESUMO

Floridoside is a galactosyl-glycerol compound that acts to supply UDP-galactose and functions as an organic osmolyte in response to salinity in Rhodophyta. Significantly, the UDP-galactose pool is shared for sulfated cell wall galactan synthesis, and, in turn, affected by thallus development alongside carposporogenesis induced by volatile growth regulators, such as ethylene and methyl jasmonate, in the red seaweed Grateloupia imbricata. In this study, we monitored changes in the floridoside reservoir through gene expression controlling both the galactose pool and glyceride pool under different reproductive stages of G. imbricata and we considered changing salinity conditions. Floridoside synthesis was followed by expression analysis of galactose-1-phosphate uridyltransferase (GALT) as UDP-galactose is obtained from UDP-glucose and glucose-1P, and through α-galactosidase gene expression as degradation of floridoside occurs through the cleavage of galactosyl residues. Meanwhile, glycerol 3-phosphate is connected with the galactoglyceride biosynthetic pathway by glycerol 3-phosphate dehydrogenase (G3PD), monogalactosyl diacylglyceride synthase (MGDGS), and digalactosyl diacylglyceride synthase (DGDGS). The results of our study confirm that low GALT transcripts are correlated with thalli softness to locate reproductive structures, as well as constricting the synthesis of UDP-hexoses for galactan backbone synthesis in the presence of two volatile regulators and methionine. Meanwhile, α-galactosidase modulates expression according to cystocarp maturation, and we found high transcripts in late development stages, as occurred in the presence of methyljasmonate, compared to early stages in ethylene. Regarding the acylglyceride pool, the upregulation of G3PD, MGDGS, and DGDGS gene expression in G. imbricata treated with MEJA supports lipid remodeling, as high levels of transcripts for MGDGS and DGDGS provide membrane stability during late development stages of cystocarps. Similar behavior is assumed in three naturally collected thalli development stages-namely, fertile, fertilized, and fertile-under 65 psu salinity conditions. Low transcripts for α-galactosidase and high for G3PD are reported in infertile and fertilized thalli, which is the opposite to high transcripts for α-galactosidase and low for G3PD encountered in fertile thalli within visible cystocarps compared to each of their corresponding stages in 35 psu. No significant changes are reported for MGDGS and DGDGS. It is concluded that cystocarp and thallus development stages affect galactose and glycerides pools with interwoven effects on cell wall polysaccharides.


Assuntos
Ciclopentanos , Glicerol/análogos & derivados , Glicerofosfatos , Oxilipinas , Rodófitas , Alga Marinha , Galactose , alfa-Galactosidase , Galactanos , Glucose , Difosfato de Uridina
12.
Plant Physiol Biochem ; 209: 108533, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520967

RESUMO

Selenium (Se) toxicity is an emerging contaminant of global concern. It is known to cause oxidative stress, affecting plant growth and yield. Plantago ovata, a major cash crop known for its medicinal properties, is often cultivated in Se-contaminated soil. Thus, the aim of this study was to evaluate the use of methyl jasmonate (MeJA) seed priming technique to mitigate Se-induced phytotoxicity. The results demonstrated that Se stress inhibited P. ovata growth, biomass and lowered chlorophyll content in a dose-dependent manner. Treatment with 1 µM MeJA enhanced the antioxidant defence system via ROS signalling and upregulated key enzymes of phenylpropanoid pathway, PAL (1.9 times) and CHI (5.4 times) in comparison to control. Caffeic acid, Vanillic acid, Chlorogenic acid, Coumaric acid and Luteoloside were the most abundant polyphenols. Enzymatic antioxidants involved in ROS scavenging, such as CAT (up to 1.3 times) and GPOX (up to 1.4 times) were raised, while SOD (by 0.6 times) was reduced. There was an upregulation of growth-inducible hormones, IAA (up to 2.1 fold) and GA (up to 1.5 fold) whereas, the stress-responsive hormones ABA (by 0.6 fold) and SA (by 0.5 fold) were downregulated. The alleviation of Se toxicity was also evident from the decrease in H2O2 and MDA contents under MeJA treatment. These findings suggest that MeJA can effectively improve Se tolerance and nutraceutical value in P. ovata by modulating the phytohormone regulatory network, redox homeostasis and elicits accumulation of polyphenols. Therefore, MeJA seed priming could be an efficient way to enhance stress resilience and sustainable crop production.


Assuntos
Acetatos , Ciclopentanos , Oxilipinas , Plantago , Selênio , Selênio/farmacologia , Selênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plantago/metabolismo , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Polifenóis/metabolismo , Hormônios/metabolismo
13.
Plant Physiol Biochem ; 208: 108483, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38457948

RESUMO

Plants produce a myriad of specialized compounds in response to threats such as pathogens or pests and different abiotic factors. The stress-related induction of specialized metabolites can be mimicked using silver nitrate (AgNO3) as an elicitor, which application in conservation agriculture has gained interest. In Arabidopsis thaliana, AgNO3 triggers the accumulation of indole glucosinolates (IGs) and the phytoalexin camalexin as well as pheylpropanoid-derived defensive metabolites such as coumaroylagmatins and scopoletin through a yet unknown mechanism. In this work, the role of jasmonic (JA) and salicylic acid (SA) signaling in the AgNO3-triggered specialized metabolite production was investigated. To attain this objective, AgNO3, MeJA and SA were applied to A. thaliana lines impaired in JA or SA signaling, or affected in the endogenous levels of IGs and AGs. Metabolomics data indicated that AgNO3 elicitation required an intact JA and SA signaling to elicit the metabolic response, although mutants impaired in hormone signaling retained certain capacity to induce specialized metabolites. In turn, plants overproducing or abolishing IGs production had also an altered hormonal signaling response, both in the accumulation of signaling molecules and the molecular response mechanisms (ORA59, PDF1.2, VSP2 and PR1 gene expression), which pointed out to a crosstalk between defense hormones and specialized metabolites. The present work provides evidence of a crosstalk mechanism between JA and SA underlying AgNO3 defense metabolite elicitation in A. thaliana. In this mechanism, IGs would act as retrograde feedback signals dampening the hormonal response; hence, expanding the signaling molecule concept.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Nitrato de Prata/farmacologia , Oxilipinas/farmacologia , Ciclopentanos/farmacologia , Ácido Salicílico/farmacologia , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética
14.
Genes (Basel) ; 15(3)2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38540383

RESUMO

Many monoterpenoid indole alkaloids (MIAs) produced in Catharanthus roseus have demonstrated biological activities and clinical potential. However, their complex biosynthesis pathway in plants leads to low accumulation, limiting therapeutic applications. Efforts to elucidate the MIA biosynthetic regulatory mechanism have focused on improving accumulation levels. Previous studies revealed that jasmonic acid (JA), an important plant hormone, effectively promotes MIA accumulation by inducing the expression of MIA biosynthesis and transport genes. Nevertheless, excessive JA signaling can strongly inhibit plant growth, decreasing MIA productivity in C. roseus. Therefore, identifying key components balancing growth and MIA production in the JA signaling pathway is imperative for effective pharmaceutical production. Here, we identify a homolog of the jasmonate transporter 1, CrJAT1, through co-expression and phylogenetic analyses. Further investigation demonstrated that CrJAT1 can activate JA signaling to promote MIA accumulation without compromising growth. The potential role of CrJAT1 in redistributing intra/inter-cellular JA and JA-Ile may calibrate signaling to avoid inhibition, representing a promising molecular breeding target in C. roseus to optimize the balance between growth and specialized metabolism for improved MIA production.


Assuntos
Catharanthus , Ciclopentanos , Oxilipinas , Alcaloides de Triptamina e Secologanina , Monoterpenos/metabolismo , Catharanthus/genética , Catharanthus/metabolismo , Filogenia , Melhoramento Vegetal , Alcaloides de Triptamina e Secologanina/metabolismo , Transdução de Sinais
15.
Plant Physiol Biochem ; 208: 108521, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38484680

RESUMO

The Agrobacterium rhizogenes root oncogenic locus (rol) genes interfere with hormone balance by altering their synthesis and/or recognition, giving rise to varied impacts on the physiological characteristics of plants and cell cultures. The homolog of the rolB and rolC genes from Ipomoea batatas, named Ib-rolB/C, similarly induces morphological and physiological alterations in transgenic Arabidopsis thaliana; however, its role in plant hormonal homeostasis has not been previously defined. In this study, we found that external application of salicylic acid (SA) and methyl jasmonate (MeJA) significantly upregulated Ib-rolB/C in detached I. batatas leaves. Furthermore, heterologous expression of Ib-rolB/C in A. thaliana markedly enhanced the accumulation of SA and MeJA, and to a lesser extent, elevated abscisic acid (ABA) levels, through the modulation of genes specific to hormone biosynthesis. Even though the RolB/RolC homolog protein has a notable structural resemblance to the RolB protein from A. rhizogenes, it exhibits a distinct localization pattern, predominantly residing in the cytoplasm and certain discrete subcellular structures, instead of the nucleus. Consequently, the functions of RolB/RolC in both naturally and artificially transgenic plants are linked to changes in the hormonal state of the cells, though the underlying signaling pathways remain to be elucidated.


Assuntos
Acetatos , Arabidopsis , Ciclopentanos , Ipomoea batatas , Oxilipinas , Arabidopsis/genética , Ipomoea batatas/genética , Ácido Salicílico/farmacologia , Vias Biossintéticas , Plantas Geneticamente Modificadas/metabolismo , Hormônios/metabolismo
16.
Drug Des Devel Ther ; 18: 597-612, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38436040

RESUMO

Purpose: New bioactive anthraquinone derivatives are investigated for antibacterial, tyrosinase inhibitory, antioxidant cytotoxic activity, and molecular docking. Methods: The compounds were produced using the grindstone method, yielding 69 to 89%. These compounds were analyzed using IR, 1H, and 13C NMR and elemental and mass spectral methods. Additionally, the antibacterial, antioxidant, and tyrosinase inhibitory activities of all the synthesised compounds were evaluated. Results: Compound 2 showed remarkable tyrosinase inhibition activity, with an (IC50: 13.45 µg/mL), compared to kojic acid (IC50: 19.40 µg/mL). It also exhibited moderate antioxidant and antibacterial activities with respect to the references BHT and ampicillin, respectively. Kinetic analysis revealed that the tyrosinase inhibitory activity of compound 2 was non-competitive and competitive, whereas that of compound 1 was low. All compounds (1-8) were significantly less active than doxorubicin (LC50: 0.74±0.01µg/mL). However, compound 2 affinity for the 2Y9X protein was lower than kojic acid, with a lower docking score (-8.6 kcal/mol compared to (-4.7 kcal/mol), making it more effective. Conclusion: All synthesized compounds displayed remarkable antibacterial, tyrosinase inhibitory, antioxidant, and cytotoxic activities, with compound 2 showing exceptional potency as a multitarget agent. Anthraquinone substituent groups may offer the potential for the development of treatments. The derivatives were synthesized using the grindstone method, and their antibacterial, antioxidant, tyrosinase inhibitory, and cytotoxic activities were inspected. Molecular docking and molecular dynamics simulations were performed using compound 2 and kojic acid to validate the results and confirm the stability of the compounds.


Assuntos
Agaricales , Antineoplásicos , Ciclopentanos , Monofenol Mono-Oxigenase , Simulação de Acoplamento Molecular , Antioxidantes/farmacologia , Cinética , Antibacterianos/farmacologia , Antraquinonas/farmacologia
17.
BMC Genomics ; 25(1): 232, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438880

RESUMO

BACKGROUND: The rose is one of the most important ornamental flowers in the world for its aesthetic beauty but can be attacked by many pests such as aphids. Aphid infestation causes tremendous damage on plant tissues leading to harmed petals and leaves. Rose cultivars express different levels of resistance to aphid infestation yet the information remains unclear. Not only that, studies about the transcriptional analysis on defending mechanisms against aphids in rose are limited so far. RESULTS: In this study, the aphid resistance of 20 rose cultivars was evaluated, and they could be sorted into six levels based on the number ratio of aphids. And then, a transcriptome analysis was conducted after aphid infestation in one high resistance (R, Harmonie) and one highly susceptibility (S, Carefree Wonder) rose cultivar. In open environment the majority of rose cultivars had the highest aphid number at May 6th or May 15th in 2020 and the resistance to infestation could be classified into six levels. Differential expression analysis revealed that there were 1,626 upregulated and 767 downregulated genes in the R cultivar and 481 upregulated and 63 downregulated genes in the S cultivar after aphid infestation. Pathway enrichment analysis of the differentially expressed genes revealed that upregulated genes in R and S cultivars were both enriched in defense response, biosynthesis of secondary metabolites (phenylpropanoid, alkaloid, and flavonoid), carbohydrate metabolism (galactose, starch, and sucrose metabolism) and lipid processing (alpha-linolenic acid and linolenic acid metabolism) pathways. In the jasmonic acid metabolic pathway, linoleate 13S-lipoxygenase was specifically upregulated in the R cultivar, while genes encoding other crucial enzymes, allene oxide synthase, allene oxide cyclase, and 12-oxophytodienoate reductase were upregulated in both cultivars. Transcription factor analysis and transcription factor binding search showed that WRKY transcription factors play a pivotal role during aphid infestation in the R cultivar. CONCLUSIONS: Our study indicated the potential roles of jasmonic acid metabolism and WRKY transcription factors during aphid resistance in rose, providing clues for future research.


Assuntos
Afídeos , Oxilipinas , Animais , Perfilação da Expressão Gênica , Ciclopentanos , Fatores de Transcrição
19.
Cell Death Dis ; 15(2): 123, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336804

RESUMO

Discovery of new small molecules that can activate distinct programmed cell death pathway is of significant interest as a research tool and for the development of novel therapeutics for pathological conditions such as cancer and infectious diseases. The small molecule raptinal was discovered as a pro-apoptotic compound that can rapidly trigger apoptosis by promoting the release of cytochrome c from the mitochondria and subsequently activating the intrinsic apoptotic pathway. As raptinal is very effective at inducing apoptosis in a variety of different cell types in vitro and in vivo, it has been used in many studies investigating cell death as well as the clearance of dying cells. While examining raptinal as an apoptosis inducer, we unexpectedly identified that in addition to its pro-apoptotic activities, raptinal can also inhibit the activity of caspase-activated Pannexin 1 (PANX1), a ubiquitously expressed transmembrane channel that regulates many cell death-associated processes. By implementing numerous biochemical, cell biological and electrophysiological approaches, we discovered that raptinal can simultaneously induce apoptosis and inhibit PANX1 activity. Surprisingly, raptinal was found to inhibit cleavage-activated PANX1 via a mechanism distinct to other well-described PANX1 inhibitors such as carbenoxolone and trovafloxacin. Furthermore, raptinal also interfered with PANX1-regulated apoptotic processes including the release of the 'find-me' signal ATP, the formation of apoptotic cell-derived extracellular vesicles, as well as NLRP3 inflammasome activation. Taken together, these data identify raptinal as the first compound that can simultaneously induce apoptosis and inhibit PANX1 channels. This has broad implications for the use of raptinal in cell death studies as well as in the development new PANX1 inhibitors.


Assuntos
Apoptose , Conexinas , Fluorenos , Trifosfato de Adenosina/metabolismo , Apoptose/efeitos dos fármacos , Morte Celular , Conexinas/antagonistas & inibidores , Conexinas/metabolismo , Ciclopentanos/farmacologia
20.
Bioorg Med Chem Lett ; 100: 129647, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38320715

RESUMO

The overexpression of neddylation modification is frequently observed in human tumor cells. Targeting the neddylation pathway has been recognized as a promising anticancer therapeutic strategy, thus discovering potent and selective neddylation inhibitors is of great importance. In this study, we designed and synthesized a series of novel neddylation inhibitors bearing benzothiazole scaffolds by molecular hybridization strategy and all compounds were evaluated for antiproliferative activity against MGC-803, MCF-7, A549 and KYSE-30 cell lines. In vitro anti-tumor studies showed that the most promising compound X-10, effectively suppressed MGC-803 cells growth and migration, induced apoptosis and arrested cell cycle at G2/M phase. Importantly, by directly interacting with NAE1, X-10 blocked NAE1 activity, specifically preventing neddylation of Cullin 3 and Cullin 1, and produced a dose-response decline in the level of UBC12-NEDD8 complex. Overall, our data indicate that X-10 inhibits the process of neddylation, making it a potentially agent for both cancer prevention and therapy purposes.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Ciclo Celular , Benzotiazóis/farmacologia , Ciclopentanos/farmacologia , Linhagem Celular Tumoral , Apoptose
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