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1.
Methods Mol Biol ; 2581: 43-56, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36413309

RESUMO

Signaling proteins trigger a sequence of molecular switches in the cell, which permit development, growth, and rapid adaptation to changing environmental conditions. SCF-type E3 ubiquitin ligases recognize signaling proteins prompting changes in their fate, one of these being ubiquitylation followed by degradation by the proteasome. SCFs together with their ubiquitylation targets (substrates) often serve as phytohormone receptors, responding and/or assembling in response to fluctuating intracellular hormone concentrations. Tracing and understanding phytohormone perception and SCF-mediated ubiquitylation of proteins could provide powerful clues on the molecular mechanisms utilized for plant adaptation. Here, we describe an adaptable in vitro system that uses recombinant proteins and enables the study of hormone-triggered SCF-substrate interaction and the dynamics of protein ubiquitylation. This system can serve to predict the requirements for protein recognition and to understand how phytohormone levels have the power to control protein fate.


Assuntos
Reguladores de Crescimento de Plantas , Ubiquitina-Proteína Ligases , Reguladores de Crescimento de Plantas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Hormônios
2.
Gene ; 850: 146905, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36181988

RESUMO

The CONSTITUTIVE PHOTOMORPHOGENIC9 (COP9) signalosome (CSN) is a multi-functional protein complex, which is involved in plant growth and abiotic stress response. However, the evolution and function of the CSN genes in land plants are still largely unclear. Here, we have identified 124 CSN genes and constructed phylogenetic trees of these CSN proteins to elucidate their feature and evolution in twelve land plants. Analysis of gene structure, protein property and protein motif composition shows the evolutional conservation and variation of the CSN proteins in land plants. These CSN genes might evolve through whole genome duplication (WGD)/segmental duplication (SD) and tandem duplication (TD). Analysis of promoter cis-elements shows that the CSN genes are implicated in diverse biological processes and different signaling pathways. RT-qPCR indicates that the transcript abundance of the OsCSN genes is up-regulated or down-regulated in response to abiotic stress and treatment with various hormones in rice. These results provide new insights into the CSN gene evolution and its possible function in land plants.


Assuntos
Embriófitas , Oryza , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Oryza/genética , Oryza/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Estresse Fisiológico/genética , Embriófitas/metabolismo , Hormônios
3.
Food Chem ; 401: 134072, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36108381

RESUMO

Plant growth regulator N-(2-chloro-4-pyridyl)-N'-phenylurea (CPPU) is widely used in fruit production. However, the mechanism in which CPPU affects melon fruit quality, especially aroma compound, remains unclear. Here, gas chromatography-mass spectrometry was performed to detect the sugar, citric acid, and aroma content in CPPU-treated and pollinated melon fruit. Results showed that the application of CPPU decreased the sugar and aroma content in melon fruit. The relative content of several important esters, including isobutyl acetate, ethyl acetate, 2-methylbutyl acetate, methyl acetate, benzyl acetate, and phenethyl acetate, in CPPU-treated fruits was significantly lower than that in honeybee-pollinated fruits. The content of many amino acids (isoleucine, leucine, valine, methionine, and l-phenylalanine), which could be metabolized into aroma compounds, in CPPU-treated fruits was significantly higher than that in honeybee-pollinated fruits. In conclusion, CPPU application interferes with amino-acid metabolism and affects the production of aromatic esters in melon fruit.


Assuntos
Cucurbitaceae , Compostos Orgânicos Voláteis , Abelhas , Animais , Frutas/metabolismo , Cucurbitaceae/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Açúcares/metabolismo , Isoleucina , Leucina/metabolismo , Metionina/metabolismo , Ácido Cítrico/metabolismo , Valina/metabolismo , Fenilalanina/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Odorantes
4.
J Hazard Mater ; 441: 129840, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36088879

RESUMO

Hyperaccumulators are plant species that tolerate and accumulate very high concentrations of toxic metals, including Cd. Hyperaccumulation of heavy metals is reported to benefit plant biotic resistance; however, no prior study has examined the possible role of toxic metals on abiotic stress resistance in hyperaccumulators. A preliminary experiment found that Cd significantly improved plant growth of a hyperaccumulator, Sedum alfredii Hance, under heat stress. This study investigated the possible role of Cd in S. alfredii's heat resistance, using infrared thermography, transmission electron microscopy (TEM), real-time quantitative polymerase chain reaction (RTqPCR), and high-throughput sequencing. The results showed that high temperatures irreversibly damaged stomatal function, chloroplast structure, photosynthesis in S. alfredii, and lowered survival rates to 25%. However, Cd application significantly decreased the leaf temperature of S. alfredii and increased the survival rate to 75%. Cd penetrated the guard cells, restored stomatal function, and mitigated excessive water loss from S. alfredii under heat stress. Moreover, it activated antioxidant enzymes, promoted phytohormone biosynthesis, and upregulated a series of unigenes, thereby augmenting heat resistance in S. alfredii. These results indicate that Cd effectively improved thermotolerance in S. alfredii by regulating stomatal movement and antioxidant systems via upregulation of phytohormones and heat shock proteins.


Assuntos
Sedum , Poluentes do Solo , Termotolerância , Antioxidantes/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Cádmio/toxicidade , Proteínas de Choque Térmico/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo , Sedum/metabolismo , Poluentes do Solo/metabolismo , Água
5.
BMC Plant Biol ; 22(1): 144, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35337273

RESUMO

Sophora davidii is an important plant resource in the karst region of Southwest China, but S. davidii plant-height mutants are rarely reported. Therefore, we performed phenotypic, anatomic structural, transcriptomic and metabolomic analyses to study the mechanisms responsible for S. davidii plant-height mutants. Phenotypic and anatomical observations showed that compared to the wild type, the dwarf mutant displayed a significant decrease in plant height, while the tall mutant displayed a significant increase in plant height. The dwarf mutant cells were smaller and more densely arranged, while those of the wild type and the tall mutant were larger and loosely arranged. Transcriptomic analysis revealed that differentially expressed genes (DEGs) involved in cell wall biosynthesis, expansion, phytohormone biosynthesis, signal transduction pathways, flavonoid biosynthesis and phenylpropanoid biosynthesis were significantly enriched in the S. davidii plant-height mutants. Metabolomic analysis revealed 57 significantly differential metabolites screened from both the dwarf and tall mutants. A total of 8 significantly different flavonoid compounds were annotated to LIPID MAPS, and three metabolites (chlorogenic acid, kaempferol and scopoletin) were involved in phenylpropanoid biosynthesis and flavonoid biosynthesis. These results shed light on the molecular mechanisms of plant height in S. davidii mutants and provide insight for further molecular breeding programs.


Assuntos
Sophora , Transcriptoma , Perfilação da Expressão Gênica , Metabolômica , Reguladores de Crescimento de Plantas/metabolismo , Sophora/genética , Sophora/metabolismo
6.
BMC Biol ; 20(1): 256, 2022 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-36372880

RESUMO

BACKGROUND: Plants are continuously challenged with biotic stress from environmental pathogens, and precise regulation of defense responses is critical for plant survival. Defense systems require considerable amounts of energy and resources, impairing plant growth, and plant hormones controlling transcriptional regulation play essential roles in establishing the appropriate balance between defense response to pathogens and growth. Chromatin regulators modulating gene transcription are broadly involved in regulating stress-responsive genes. However, which chromatin factors are involved in coordinating hormone signaling and immune responses in plants, and their functional mechanisms, remains unclear. Here, we identified a role of bromodomain-containing protein GTE4 in negatively regulating defense responses in Arabidopsis thaliana. RESULTS: GTE4 mainly functions as activator of gene expression upon infection with Pseudomonas syringe. Genome-wide profiling of GTE4 occupancy shows that GTE4 tends to bind to active genes, including ribosome biogenesis related genes and maintains their high expression levels during pathogen infection. However, GTE4 is also able to repress gene expression. GTE4 binds to and represses jasmonate biosynthesis gene OPR3. Disruption of GTE4 results in overaccumulation of jasmonic acid (JA) and enhanced JA-responsive gene expression. Unexpectedly, over-accumulated JA content in gte4 mutant is coupled with downregulation of JA-mediated immune defense genes and upregulation of salicylic acid (SA)-mediated immune defense genes, and enhanced resistance to Pseudomonas, likely through a noncanonical pathway. CONCLUSIONS: Overall, we identified a new role of the chromatin factor GTE4 as negative regulator of plant immune response through inhibition of JA biosynthesis, which in turn noncanonically activates the defense system against Pseudomonas. These findings provide new knowledge of chromatic regulation of plant hormone signaling during defense responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Etilenos/metabolismo , Etilenos/farmacologia , Doenças das Plantas/genética , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Ácido Salicílico/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Imunidade , Cromatina/metabolismo
7.
Int J Mol Sci ; 23(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36361778

RESUMO

Ethylene (ETH), as a key plant hormone, plays critical roles in various processes of plant growth and development. ETH has been reported to induce adventitious rooting. Moreover, our previous studies have shown that exogenous ETH may induce plant adventitious root development in cucumber (Cucumis sativus L.). However, the key genes involved in this process are still unclear. To explore the key genes in ETH-induced adventitious root development, we employed a transcriptome technique and revealed 1415 differentially expressed genes (DEGs), with 687 DEGs up-regulated and 728 DEGs down-regulated. Using Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, we further identified critical pathways that were involved in ETH-induced adventitious root development, including carbon metabolism (starch and sucrose metabolism, glycolysis/gluconeogenesis, citrate cycle (TCA cycle), oxidative phosphorylation, fatty acid biosynthesis, and fatty acid degradation), secondary metabolism (phenylalanine metabolism and flavonoid biosynthesis) and plant hormone signal transduction. In carbon metabolism, ETH reduced the content of sucrose, glucose, starch, the activity of sucrose synthase (SS), sucrose-phosphate synthase (SPS) and hexokinase (HK), and the expressions of CsHK2, pyruvate kinase2 (CsPK2), and CsCYP86A1, whereas it enhanced the expressions of ß-amylase 1 (CsBAM1) and ß-amylase 3 (CsBAM3). In secondary metabolism, the transcript levels of phenylalanine ammonia-lyase (CsPAL) and flavonoid 3'-monooxygenase (CsF3'M) were negatively regulated, and that of primary-amine oxidase (CsPAO) was positively regulated by ETH. Additionally, the indole-3-acetic acid (IAA) content and the expressions of auxin and ETH signaling transduction-related genes (auxin transporter-like protein 5 (CsLAX5), CsGH3.17, CsSUAR50, and CsERS) were suppressed, whereas the abscisic acid (ABA) content and the expressions of ABA and BR signaling transduction-related genes (CsPYL1, CsPYL5, CsPYL8, BRI1-associated kinase 1 (CsBAK1), and CsXTH3) were promoted by ETH. Furthermore, the mRNA levels of these genes were confirmed by real-time PCR (RT-qPCR). These results indicate that genes related to carbon metabolism, secondary metabolite biosynthesis, and plant hormone signaling transduction are involved in ETH-induced adventitious root development. This work identified the key pathways and genes in ETH-induced adventitious rooting in cucumber, which may provide new insights into ETH-induced adventitious root development and will be useful for investigating the molecular roles of key genes in this process in further studies.


Assuntos
Cucumis sativus , beta-Amilase , Cucumis sativus/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , beta-Amilase/genética , beta-Amilase/metabolismo , Raízes de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Etilenos/metabolismo , Ácido Abscísico/metabolismo , Amido/metabolismo , Sacarose/metabolismo , Carbono/metabolismo , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361817

RESUMO

Floral initiation is a major phase change in the spermatophyte, where developmental programs switch from vegetative growth to reproductive growth. It is a key phase of flowering in tea-oil trees that can affect flowering time and yield, but very little is known about the molecular mechanism of floral initiation in tea-oil trees. A 12-year-old Camellia oleifera (cultivar 'changlin53') was the source of experimental materials in the current study. Scanning electron microscopy was used to identify the key stage of floral initiation, and transcriptome analysis was used to reveal the transcriptional regulatory network in old leaves involved in floral initiation. We mined 5 DEGs related to energy and 55 DEGs related to plant hormone signal transduction, and we found floral initiation induction required a high level of energy metabolism, and the phytohormones signals in the old leaves regulate floral initiation, which occurred at stage I and II. Twenty-seven rhythm-related DEGs and 107 genes associated with flowering were also identified, and the circadian rhythm interacted with photoperiod pathways to induce floral initiation. Unigene0017292 (PSEUDO-RESPONSE REGULATOR), Unigene0046809 (LATE ELONGATED HYPOCOTYL), Unigene0009932 (GIGANTEA), Unigene0001842 (CONSTANS), and Unigene0084708 (FLOWER LOCUS T) were the key genes in the circadian rhythm-photoperiod regulatory network. In conjunction with morphological observations and transcriptomic analysis, we concluded that the induction of floral initiation by old leaves in C. oleifera 'changlin53' mainly occurred during stages I and II, floral initiation was completed during stage III, and rhythm-photoperiod interactions may be the source of the main signals in floral initiation induced by old leaves.


Assuntos
Camellia , Camellia/genética , Camellia/metabolismo , Árvores/genética , Perfilação da Expressão Gênica , Flores/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Chá/metabolismo , Transcriptoma , Regulação da Expressão Gênica de Plantas
9.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362292

RESUMO

Warm temperatures induce plant bolting accompanied by flower initiation, where endogenous auxin is dynamically associated with accelerated growth. Auxin signaling is primarily regulated by a family of plant-specific transcription factors, AUXIN RESPONSE FACTORS (ARFs), which either activate or repress the expression of downstream genes in response to developmental and environmental cues. However, the relationship between ARFs and bolting has not been completely understood in lettuce yet. Here, we identified 24 LsARFs (Lactuca sativa ARFs) in the lettuce genome. The phylogenetic tree indicated that LsARFs could be classified into three clusters, which was well supported by the analysis of exon-intron structure, consensus motifs, and domain compositions. RNA-Seq analysis revealed that more than half of the LsARFs were ubiquitously expressed in all tissues examined, whereas a small number of LsARFs responded to UV or cadmium stresses. qRT-PCR analysis indicated that the expression of most LsARFs could be activated by more than one phytohormone, underling their key roles as integrative hubs of different phytohormone signaling pathways. Importantly, the majority of LsARFs displayed altered expression profiles under warm temperatures, implying that their functions were tightly associated with thermally accelerated bolting in lettuce. Importantly, we demonstrated that silencing of LsARF8a, expression of which was significantly increased by elevated temperatures, resulted in delayed bolting under warm temperatures, suggesting that LsARF8a might conduce to the thermally induced bolting. Together, our results provide molecular insights into the LsARF gene family in lettuce, which will facilitate the genetic improvement of the lettuce in an era of global warming.


Assuntos
Ácidos Indolacéticos , Alface , Alface/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Regulação da Expressão Gênica de Plantas
10.
J Agric Food Chem ; 70(45): 14352-14366, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36326728

RESUMO

Diuron [DU; 3-(3,4-dichlorophenyl)-1,1-dimethylurea], a widely used herbicide for weed control, arouses ecological and health risks due to its environment persistence. Our findings revealed that DU at 0.125-2.0 mg L-1 caused oxidative damage to rice. RNA-sequencing profiles disclosed a globally genetic expression landscape of rice under DU treatment. DU mediated downregulated gene encoding photosynthesis and biosynthesis of protein, fatty acid, and carbohydrate. Conversely, it induced the upregulation of numerous genes involved in xenobiotic metabolism, detoxification, and anti-oxidation. Furthermore, 15 DU metabolites produced by metabolic genes were identified, 7 of which include two Phase I-based and 5 Phase II-based derivatives, were reported for the first time. The changes of resistance-related phytohormones, like JA, ABA, and SA, in terms of their contents and molecular-regulated signaling pathways positively responded to DU stress. Our work provides a molecular-scale perspective on the response of rice to DU toxicity and clarifies the biotransformation and degradation fate of DU in rice crops.


Assuntos
Herbicidas , Oryza , Diurona/metabolismo , Oryza/genética , Oryza/metabolismo , Herbicidas/farmacologia , Herbicidas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Estresse Oxidativo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas
11.
BMC Plant Biol ; 22(1): 529, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376794

RESUMO

BACKGROUND: Dendrobium officinale Kimura et Migo, which contains rich polysaccharides, flavonoids and alkaloids, is a Traditional Chinese Medicine (TCM) with important economic benefits, while various pathogens have brought huge losses to its industrialization. NBS gene family is the largest class of plant disease resistance (R) genes, proteins of which are widely distributed in the upstream and downstream of the plant immune systems and are responsible for receiving infection signals and regulating gene expression respectively. It is of great significance for the subsequent disease resistance breeding of D. officinale to identify NBS genes by using the newly published high-quality chromosome-level D. officinale genome. RESULTS: In this study, a total of 655 NBS genes were uncovered from the genomes of D. officinale, D. nobile, D. chrysotoxum, V. planifolia, A. shenzhenica, P. equestris and A. thaliana. The phylogenetic results of CNL-type protein sequences showed that orchid NBS-LRR genes have significantly degenerated on branches a and b. The Dendrobium NBS gene homology analysis showed that the Dendrobium NBS genes have two obvious characteristics: type changing and NB-ARC domain degeneration. Because the NBS-LRR genes have both NB-ARC and LRR domains, 22 D. officinale NBS-LRR genes were used for subsequent analyses, such as gene structures, conserved motifs, cis-elements and functional annotation analyses. All these results suggested that D. officinale NBS-LRR genes take part in the ETI system, plant hormone signal transduction pathway and Ras signaling pathway. Finally, there were 1,677 DEGs identified from the salicylic acid (SA) treatment transcriptome data of D. officinale. Among them, six NBS-LRR genes (Dof013264, Dof020566, Dof019188, Dof019191, Dof020138 and Dof020707) were significantly up-regulated. However, only Dof020138 was closely related to other pathways from the results of WGCNA, such as pathogen identification pathways, MAPK signaling pathways, plant hormone signal transduction pathways, biosynthetic pathways and energy metabolism pathways. CONCLUSION: Our results revealed that the NBS gene degenerations are common in the genus Dendrobium, which is the main reason for the diversity of NBS genes, and the NBS-LRR genes generally take part in D. officinale ETI system and signal transduction pathways. In addition, the D. officinale NBS-LRR gene Dof020138, which may have an important breeding value, is indirectly activated by SA in the ETI system.


Assuntos
Dendrobium , Ácido Salicílico , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Dendrobium/genética , Dendrobium/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Resistência à Doença/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Melhoramento Vegetal , Transcriptoma
12.
Sci Data ; 9(1): 669, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329059

RESUMO

Rose is one of the most important ornamental plants, accounting for one-third of the world's fresh cut flower market. The vase life refers to the period of a cut flower retaining its appearance in a vase. During this period, the rose was subjected to a variety of abiotic and biotic stresses, resulting in a reduction in the life of cut flowers. Numerous studies have been carried out on cut rose, which proves the effects of various plant hormones on post-harvest dehydration, petal senescence and abscission, disease and vase life of cut rose flowers. In addition, the natural or synthetic hormones or its inhibitor have been successfully used in cut flower preservatives to extend the vase life of rose. However, there is still a lack of systematic and in-depth research on the expression of rose genes related to plant hormone response. Here we analyzed the gene expression changes of the rose flower under treatment of 11 different plant hormones or its inhibitors in order to provide reference for rose studies.


Assuntos
Reguladores de Crescimento de Plantas , Rosa , Flores/genética , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Rosa/genética , Estresse Fisiológico , Transcriptoma
13.
Mol Plant ; 15(11): 1759-1771, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36199245

RESUMO

It is well known that plants activate defense responses at the cost of growth. However, the underlying molecular mechanisms are not well understood. The phytohormones salicylic acid (SA) and gibberellin (GA) promote defense response and growth, respectively. Here we show that SA inhibits GA signaling to repress plant growth. We found that the SA receptor NPR1 interacts with the GA receptor GID1. Further biochemical studies revealed that NPR1 functions as an adaptor of ubiquitin E3 ligase to promote the polyubiquitination and degradation of GID1, which enhances the stability of DELLA proteins, the negative regulators of GA signaling. Genetic analysis suggested that NPR1, GID1, and DELLA proteins are all required for the SA-mediated growth inhibition. Collectively, our study not only uncovers a novel regulatory mechanism of growth-defense trade-off but also reveals the interaction of hormone receptors as a new mode of hormonal crosstalk.


Assuntos
Proteínas de Arabidopsis , Giberelinas , Giberelinas/metabolismo , Ácido Salicílico , Receptores de Superfície Celular/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
14.
Nat Microbiol ; 7(11): 1817-1833, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36266335

RESUMO

Chemical signalling in the plant microbiome can have drastic effects on microbial community structure, and on host growth and development. Previously, we demonstrated that the auxin metabolic signal interference performed by the bacterial genus Variovorax via an auxin degradation locus was essential for maintaining stereotypic root development in an ecologically relevant bacterial synthetic community. Here, we dissect the Variovorax auxin degradation locus to define the genes iadDE as necessary and sufficient for indole-3-acetic acid (IAA) degradation and signal interference. We determine the crystal structures and binding properties of the operon's MarR-family repressor with IAA and other auxins. Auxin degradation operons were identified across the bacterial tree of life and we define two distinct types on the basis of gene content and metabolic products: iac-like and iad-like. The structures of MarRs from representatives of each auxin degradation operon type establish that each has distinct IAA-binding pockets. Comparison of representative IAA-degrading strains from diverse bacterial genera colonizing Arabidopsis plants show that while all degrade IAA, only strains containing iad-like auxin-degrading operons interfere with auxin signalling in a complex synthetic community context. This suggests that iad-like operon-containing bacterial strains, including Variovorax species, play a key ecological role in modulating auxins in the plant microbiome.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Microbiota , Reguladores de Crescimento de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Plantas/metabolismo
15.
J Plant Physiol ; 279: 153836, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36244262

RESUMO

Irrational use of pesticides may lead to physiological and metabolic disorders in different crops. However, there are limited investigations on impacts of insecticides on physiology and biochemistry, secondary metabolic pathways, and associated quality of medicinal plants such as peppermint (Mentha × piperita L.). In this study, target metabolites in peppermint were monitored following foliar spraying of five insecticides: imidacloprid, pyriproxyfen, acetamiprid, chlorantraniliprole, and chlorfenapyr. Compared with the control, all insecticide treatments caused a significant loss of soluble protein (decreased by 22.3-38.7%) in peppermint leaves. Insecticides induced an increase in the levels of phytohormones jasmonic acid and abscisic acid in response to these chemical stresses. Among them, imidacloprid increased jasmonic acid by 388.3%, and pyriproxyfen increased abscisic acid by 98.8%. The contents of phenylpropanoid metabolites, including rutin, quercetin, apigenin, caffeic acid, 4-hydroxybenzoic acid, ferulic acid, syringic acid, and sinapic acid showed a decreasing trend, with pyriproxyfen decreasing the levels of quercetin and 4-hydroxybenzoic acid by 78.8% and 72.6%, respectively. Combined with correlation analysis, the content of lignin in leaves shows different degrees of negative correlations with several phenolic acids. It could be inferred that insecticides may trigger plant defense mechanisms that accumulate lignin (increased by 24.6-49.1%) in leaves by consuming phenolic acids to barricade absorption of insecticides. Through constructing networks between phytohormones and secondary metabolites, peppermint may regulate the contents of caffeic acid, 4-hydroxybenzoic acid, and sinapic acid by the antagonistic effect between salicylic acid and abscisic acid in response to insecticidal stresses. Principal component analysis and systemic cluster analysis revealed that the most pronounced changes in physiological indexes and metabolites were caused by the pyriproxyfen treatment. In conclusion, this study improves our understanding of the mechanism by which insecticides affect plant physiological and metabolic processes, thus potentially altering the quality and therapeutic value of peppermint as an example.


Assuntos
Inseticidas , Mentha piperita , Mentha piperita/metabolismo , Inseticidas/farmacologia , Inseticidas/análise , Inseticidas/metabolismo , Lignina/metabolismo , Parabenos/análise , Parabenos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Quercetina/análise , Folhas de Planta/metabolismo , Ácidos Cafeicos/análise , Ácidos Cafeicos/metabolismo
16.
J Plant Physiol ; 279: 153835, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36257086

RESUMO

Bud dormancy and its release are complex physiological phenomena in plants. The molecular mechanisms of bud dormancy in Liriodendron chinense are mainly unknown. Here, we studied bud dormancy and the related physiological and molecular phenomena in Liriodendron under long-day (LD) and short-day (SD). Bud burst was released faster under LD than under SD. Abscisic acid (ABA), superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR) activities were increased significantly under LD in Liriodendron buds. In contrast, the contents of gibberellic acid (GA3), ascorbic acid (AsA), glutathione (GSH), malondialdehyde (MDA), and ascorbate peroxidase (APX) activity decreased under LD but increased under SD. Differentially expressed genes (DEGs) were up-regulated under LD and down-regulated under SD and these changes correspondingly promoted (LD) or repressed (SD) cell division and the number and/or size of cells in the bud. Transcriptomic analysis of Liriodendron buds under different photoperiods identified 187 DEGs enriched in several pathways such as flavonoid biosynthesis and phenylpropanoid biosynthesis, plant hormone and signal transduction, etc. that are associated with antioxidant enzymes, non-enzymatic antioxidants, and subsequently promote the growth of the buds. Our findings provide novel insights into regulating bud dormancy via flavonoid and phenylpropanoid biosynthesis, plant hormone and signal transduction pathways, and ABA content. These physiological and biochemical traits would help detect bud dormancy in plants.


Assuntos
Liriodendron , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Fotoperíodo , Liriodendron/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Flavonoides , Dormência de Plantas/genética
17.
Plant Mol Biol ; 110(6): 455-468, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36255595

RESUMO

Tubby-like proteins (TLPs) transcription factors are found in single-celled to multi-cellular eukaryotes in the form of large multigene families. TLPs are identified through a specific signature of carboxyl terminal tubby domain, required for plasma membrane tethering and amino terminal F-box domain communicate as functional SCF-type E3 ligases. The comprehensive distribution of TLP gene family members in diverse species indicates some conserved functions of TLPs in multicellular organisms. Plant TLPs have higher gene members than animals and these members reported important role in multiple physiological and developmental processes and various environmental stress responses. Although the TLPs are suggested to be a putative transcription factors but their functional mechanism is not much clear. This review provides significant recent updates on TLP-mediated regulation with an insight into its functional roles, origin and evolution and also phytohormones related regulation to combat with various stresses and its involvement in adaptive stress response in crop plants.


Assuntos
Plantas , Fatores de Transcrição , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Plantas/genética , Plantas/metabolismo , Estresse Fisiológico , Reguladores de Crescimento de Plantas/metabolismo
18.
Int J Mol Sci ; 23(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36293506

RESUMO

The accumulation of carotenoids in plants is a key nutritional quality in many horticultural crops. Although the structural genes encoding the biosynthetic enzymes are well-characterized, little is known regarding photoperiod-mediated carotenoid accumulation in the fruits of some horticultural crops. Herein, we performed physiological and transcriptomic analyses using two cucumber genotypes, SWCC8 (XIS-orange-fleshed and photoperiod-sensitive) and CC3 (white-fleshed and photoperiod-non-sensitive), established under two photoperiod conditions (8L/16D vs. 12L/12D) at four fruit developmental stages. Day-neutral treatments significantly increased fruit ß-carotene content by 42.1% compared to short day (SD) treatments in SWCC8 at 40 DAP with no significant changes in CC3. Day-neutral condition elevated sugar levels of fruits compared to short-day treatments. According to GO and KEGG analyses, the predominantly expressed genes were related to photosynthesis, carotenoid biosynthesis, plant hormone signaling, circadian rhythms, and carbohydrates. Consistent with ß-carotene accumulation in SWCC8, the day-neutral condition elevated the expression of key carotenoid biosynthesis genes such as PSY1, PDS, ZDS1, LYCB, and CHYB1 during later stages between 30 to 40 days of fruit development. Compared to SWCC8, CC3 showed an expression of DEGs related to carotenoid cleavage and oxidative stresses, signifying reduced ß-carotene levels in CC3 cucumber. Further, a WGCNA analysis revealed co-expression between carbohydrate-related genes (pentose-phosphatase synthase, ß-glucosidase, and trehalose-6-phosphatase), photoperiod-signaling genes (LHY, APRR7/5, FKF1, PIF3, COP1, GIGANTEA, and CK2) and carotenoid-biosynthetic genes, thus suggesting that a cross-talk mechanism between carbohydrates and light-related genes induces ß-carotene accumulation. The results highlighted herein provide a framework for future gene functional analyses and molecular breeding towards enhanced carotenoid accumulation in edible plant organs.


Assuntos
Celulases , Cucumis sativus , Frutas/química , Cucumis sativus/genética , Cucumis sativus/metabolismo , Transcriptoma , beta Caroteno/metabolismo , Regulação da Expressão Gênica de Plantas , Fotoperíodo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Trealose/metabolismo , Carotenoides/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Pentoses/análise , Pentoses/metabolismo , Celulases/metabolismo
19.
Methods Enzymol ; 676: 239-278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36280352

RESUMO

The plant hormone auxin plays important roles throughout the entire life span of a plant and facilitates its adaptation to a changing environment. Multiple metabolic pathways intersect to control the levels and flux through indole-3-acetic acid (IAA), the primary auxin in most plant species. Measurement of changes in these pathways represents an important objective to understanding core aspects of auxin signal regulation. Such studies have become approachable through the technologies encompassed by targeted metabolomics. By monitoring incorporation of stable isotopes from labeled precursors into proposed intermediates, it is possible to trace pathway utilization and characterize new biosynthetic routes to auxin. Chemical inhibitors that target specific steps or entire pathways related to auxin synthesis aid these techniques. Here we describe methods for obtaining stable isotope labeled pathway intermediates necessary for pathway analysis and quantification of compounds. We describe how to use isotope dilution with methods employing either gas chromatography or high performance liquid chromatography mass spectrometry techniques for sensitive analysis of IAA. Complete biosynthetic pathway analysis in seedlings using multiple stable isotope-labeled precursors and chemical inhibitors coupled with highly sensitive liquid chromatography-mass spectrometry methods are described that allow rapid measurement of isotopic flux into biochemical pools. These methods should prove to be useful to researchers studying aspects of the auxin metabolic network in vivo in a variety of plant tissues and during various environmental conditions.


Assuntos
Ácidos Indolacéticos , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/análise , Reguladores de Crescimento de Plantas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Indolacéticos/análise , Ácidos Indolacéticos/metabolismo , Plantas/metabolismo , Indóis/metabolismo , Metabolômica
20.
Int J Mol Sci ; 23(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36232602

RESUMO

Agriculture is facing increasing challenges with regard to achieving sustainable growth in productivity without negatively impacting the environment. The use of bioinoculants is emerging as a sustainable solution for agriculture, especially bioinoculants based on diazotrophic bacteria. Brazil is at the forefront of studies intended to identify beneficial diazotrophic bacteria, as well as in the molecular characterization of this association on both the bacterial and plant sides. Here we highlight the main advances in molecular studies to understand the benefits brought to plants by diazotrophic bacteria. Different molecular pathways in plants are regulated both genetically and epigenetically, providing better plant performance. Among them, we discuss the involvement of genes related to nitrogen metabolism, cell wall formation, antioxidant metabolism, and regulation of phytohormones that can coordinate plant responses to environmental factors. Another important aspect in this regard is how the plant recognizes the microorganism as beneficial. A better understanding of plant-bacteria-environment interactions can assist in the future formulation of more efficient bioinoculants, which could in turn contribute to more sustainable agriculture practices.


Assuntos
Antioxidantes , Reguladores de Crescimento de Plantas , Agricultura/métodos , Antioxidantes/metabolismo , Bactérias/genética , Bactérias/metabolismo , Produtos Agrícolas , Nitrogênio/metabolismo , Reguladores de Crescimento de Plantas/metabolismo
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