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1.
Bioresour Technol ; 291: 121883, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31387052

RESUMO

In this study, the interactive effect of plant hormone-salicylic acid and succinic acid on biomass growth, lutein content, and productivity of Desmodesmus sp. F51 were investigated. The results demonstrated that the synergistic action of salicylic acid and succinic acid could effectively enhance the assimilation of nitrate and significantly improve lutein production. The maximal lutein content 7.01 mg/g and productivity 5.11 mg/L/d could be obtained with a supplement of 100 µM salicylic acid and 2.5 mM succinic acid in batch culture. Furthermore, operation strategy of nitrate fed-batch coupled with supplementation for succinic acid and salicylic acid resulted in further enhancement of lutein content and productivity by 7.50 mg/g and 5.78 mg/L/d, respectively. The performance is better than most of the previously reported values.


Assuntos
Biomassa , Luteína/biossíntese , Nitratos/farmacologia , Reguladores de Crescimento de Planta/farmacologia
2.
J Agric Food Chem ; 67(35): 9958-9966, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31419123

RESUMO

Chilling injury (CI) is a physiological disorder induced by cold, which heavily limit crop production and postharvest preservation worldwide. Methyl jasmonate (MeJA) can alleviate CI in various fruit species, including peach; however, the underlying molecular mechanism is poorly understood. Here, changes in contents of phenolics, lipids, and jasmonic acid (JA) and gene expressions are compared between MeJA and control fruit. Exogenous MeJA inhibited expressions of PpPAL1, PpPPO1, and PpPOD1/2 but did not affect the phenolic content. Furthermore, MeJA fruit showed lower relative electrolyte leakage, indicating less membrane damage. Meanwhile, the enrichment of linoleic acid in the potential lipid biomarkers, especially phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol, coincided with lower expressions of PpFAD8.1 but higher PpLOX3.1 and JA content. In the JA signaling pathway, MeJA significantly upregulated expressions of PpMYC2.2 and PpCBF3 but downregulated PpMYC2.1. In conclusion, adjustments of fatty acids in phospholipids contribute to MeJA-induced alleviation of CI in peach fruit via induction of the JA-mediated C-repeat-binding factor pathway.


Assuntos
Acetatos/farmacologia , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Frutas/efeitos dos fármacos , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Fosfolipídeos/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Prunus persica/metabolismo , Temperatura Baixa , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prunus persica/efeitos dos fármacos , Prunus persica/genética , Prunus persica/crescimento & desenvolvimento
3.
BMC Plant Biol ; 19(1): 327, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324148

RESUMO

BACKGROUND: Diethyl aminoethyl hexanoate (DA-6), a plant growth regulator, has many beneficial effects on agricultural production. DA-6 has been applied to many plant species, but the molecular mechanism by which spraying DA-6 after anthesis regulates wheat grain filling is still unknown. RESULTS: In this study, we used four DA-6 concentrations: C0 (0 g/L), C2 (2 g/L), C4 (4 g/L), and C6 (6 g/L). The results showed that C4 and C6 led to a significantly higher 1000-grain weight and seed protein content than C0 during two wheat growing seasons. We then subjected samples at 24 days after anthesis (at which point the grain weight increased rapidly) to transcriptome analysis. Flag leaf (L), seed (S), and stem (T) samples under C6 and C0 were used for RNA-seq. The seed samples under C6 compared with C0 (S6vsS0) presented the most differentially expressed genes (DEGs; 2164). Plant hormone signal transduction (p = 1.97 × 10- 4), protein processing in the endoplasmic reticulum (ER; p = 9.04 × 10- 11) and starch and sucrose metabolism (p = 1.90 × 10- 10) pathways were the most markedly enriched pathways in the flag leaves, stems, and seeds, respectively. DEGs involved in sucrose synthesis in the flag leaves, protein processing in ER in the stems, and starch synthesis and protein processing in ER in the seeds were significantly upregulated under C6 compared with C0. CONCLUSIONS: Overall, we propose a model for spraying DA-6 after anthesis to regulate metabolic pathways in wheat, which provides new insights into wheat in response to DA-6.


Assuntos
Caproatos/farmacologia , Grão Comestível/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Triticum/efeitos dos fármacos , Relação Dose-Resposta a Droga , Grão Comestível/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Proteínas de Armazenamento de Sementes/metabolismo , Triticum/crescimento & desenvolvimento
4.
Plant Mol Biol ; 101(1-2): 149-162, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267255

RESUMO

KEY MESSAGE: Here we describe that the regulation of MdWRKY31 on MdHIR4 in transcription and translation levels associated with disease in apple. The phytohormone salicylic acid (SA) is a main factor in apple (Malus domestica) production due to its function in disease resistance. WRKY transcription factors play a vital role in response to stress. An RNA-seq analysis was conducted with 'Royal Gala' seedlings treated with SA to identify the WRKY regulatory mechanism of disease resistance in apple. The analysis indicated that MdWRKY31 was induced. A quantitative real-time polymerase chain reaction (qPCR) analysis demonstrated that the expression of MdWRKY31 was induced by SA and flg22. Ectopic expression of MdWRKY31 in Arabidopsis and Nicotiana benthamiana increased the resistance to flg22 and Pseudomonas syringae tomato (Pst DC3000). A yeast two-hybrid screen was conducted to further analyze the function of MdWRKY31. As a result, hypersensitive-induced reaction (HIR) protein MdHIR4 interacted with MdWRKY31. Biomolecular fluorescence complementation, yeast two-hybrid, and pull-down assays demonstrated the interaction. In our previous study, MdHIR4 conferred decreased resistance to Botryosphaeria dothidea (B. dothidea). A viral vector-based transformation assay indicated that MdWRKY31 evaluated the transcription of SA-related genes, including MdPR1, MdPR5, and MdNPR1 in an MdHIR4-dependent way. A GUS analysis demonstrated that the w-box, particularly w-box2, of the MdHIR4 promoter played a major role in the responses to SA and B. dothidea. Electrophoretic mobility shift assays, yeast one-hybrid assay, and chromatin immunoprecipitation-qPCR demonstrated that MdWRKY31 directly bound to the w-box2 motif in the MdHIR4 promoter. GUS staining activity and a protein intensity analysis further showed that MdWRKY31 repressed MdHIR4 expression. Taken together, our findings reveal that MdWRKY31 regulated plant resistance to B. dothidea through the SA signaling pathway by interacting with MdHIR4.


Assuntos
Resistência à Doença , Malus/genética , Doenças das Plantas/imunologia , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacologia , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/microbiologia , Ascomicetos/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Frutas/genética , Frutas/imunologia , Frutas/microbiologia , Regulação da Expressão Gênica de Plantas , Genes Reporter , Malus/imunologia , Malus/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Pseudomonas syringae/fisiologia , Plântula/genética , Plântula/imunologia , Plântula/microbiologia , Transdução de Sinais , Tabaco/genética , Tabaco/imunologia , Tabaco/microbiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
5.
J Sci Food Agric ; 99(13): 6089-6096, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31250437

RESUMO

BACKGROUND: Panax ginseng seeds have strong dormancy and a prolonged germination period in comparison to other seeds; thus, it is a great challenge to propagate ginseng. Seed longevity is closely associated with germination rate and viability, so we assumed that if a seed loses its viability, specific metabolic alterations regarding plant growth factors might occur. In this study, we divided ginseng seeds into normal and accelerated-aging groups. Both groups were treated with gibberellic acid, which is one of the most important plant-growth regulators. Afterward, gas chromatography-mass spectrometry (GC-MS) was used to analyze the samples, to identify the metabolic alterations between the two groups. RESULTS: Forty-four endogenous metabolites in normal and accelerated aging groups were putatively identified. To determine the differential significance of these metabolites, t-tests and fold-change analysis were conducted followed by principal component analysis and partial least-squares discriminant analysis to determine the metabolites that showed distinct responses between the groups. Among the differentially expressed metabolites (P value < 0.05 and FDR < 0.1), nine metabolites were selected as potential biomarker candidates for the prediction of seed longevity. CONCLUSION: Nine metabolites related to ginseng seed longevity were identified by comparing metabolomes. Our findings suggest that ginseng propagation can be facilitated by the regulation of these distinctive metabolic features of the seeds. © 2019 Society of Chemical Industry.


Assuntos
Panax/metabolismo , Extratos Vegetais/química , Sementes/química , Análise Discriminante , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Giberelinas/farmacologia , Análise dos Mínimos Quadrados , Metabolômica , Panax/química , Panax/efeitos dos fármacos , Panax/crescimento & desenvolvimento , Extratos Vegetais/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
6.
BMC Plant Biol ; 19(1): 285, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253103

RESUMO

BACKGROUND: Sugarcane is a major crop producing about 80% of sugar globally. Increasing sugar content is a top priority for sugarcane breeding programs worldwide, however, the progress is extremely slow. Owing to its commercial significance, the physiology of sucrose accumulation has been studied extensively but it did not lead to any significant practical outcomes. Recent molecular studies are beginning to recognize genes and gene networks associated with this phenomenon. To further advance our molecular understanding of sucrose accumulation, we altered sucrose content of sugarcane genotypes with inherently large variation for sucrose accumulation using a sugarcane ripener, ethylene, and studied their transcriptomes to identify genes associated with the phenomenon. RESULTS: Sucrose content variation in the experimental genotypes was substantial, with the top-performing clone producing almost 60% more sucrose than the poorest performer. Ethylene treatment increased stem sucrose content but that occurred only in low-sugar genotype. Transcriptomic analyses have identified about 160,000 unigenes of which 86,000 annotated genes were classified into functional groups associated with carbohydrate metabolism, signaling, localization, transport, hydrolysis, growth, catalytic activity, membrane and storage, suggesting the structural and functional specification, including sucrose accumulation, occurring in maturing internodes. About 25,000 genes were differentially expressed between all genotypes and treatments combined. Genotype had a dominant effect on differential gene expression than ethylene treatment. Sucrose and starch metabolism genes were more responsive to ethylene treatment in low-sugar genotype. Ethylene caused differential gene expression of many stress-related transcription factors, carbohydrate metabolism, hormone metabolism and epigenetic modification. Ethylene-induced expression of ethylene-responsive transcription factors, cytosolic acid- and cell wall-bound invertases, and ATPase was more pronounced in low- than in high-sugar genotype, suggesting an ethylene-stimulated sink activity and consequent increased sucrose accumulation in low-sugar genotype. CONCLUSION: Ethylene-induced sucrose accumulation is more pronounced in low-sugar sugarcane genotype, and this is possibly achieved by the preferential activation of genes such as invertases that increase sink strength in the stem. The relatively high enrichment of differentially expressed genes associated with hormone metabolism and signaling and stress suggests a strong hormonal regulation of source-sink activity, growth and sucrose accumulation in sugarcane.


Assuntos
Etilenos/farmacologia , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Planta/farmacologia , Saccharum/fisiologia , Sacarose/metabolismo , Genótipo , Saccharum/crescimento & desenvolvimento , Transcriptoma
7.
J Microbiol Biotechnol ; 29(7): 1124-1136, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216607

RESUMO

Salinity is one of the major abiotic stresses that cause reduction of plant growth and crop productivity. It has been reported that plant growth-promoting bacteria (PGPB) could confer abiotic stress tolerance to plants. In a previous study, we screened bacterial strains capable of enhancing plant health under abiotic stresses and identified these strains based on 16s rRNA sequencing analysis. In this study, we investigated the effects of two selected strains, Bacillus aryabhattai H19-1 and B. mesonae H20-5, on responses of tomato plants against salinity stress. As a result, they alleviated decrease in plant growth and chlorophyll content; only strain H19-1 increased carotenoid content compared to that in untreated plants under salinity stress. Strains H19-1 and H20-5 significantly decreased electrolyte leakage, whereas they increased Ca2+ content compared to that in the untreated control. Our results also indicated that H20-5-treated plants accumulated significantly higher levels of proline, abscisic acid (ABA), and antioxidant enzyme activities compared to untreated and H19-1-treated plants during salinity stress. Moreover, strain H20-5 upregulated 9-cisepoxycarotenoid dioxygenase 1 (NCED1) and abscisic acid-response element-binding proteins 1 (AREB1) genes, otherwise strain H19-1 downregulated AREB1 in tomato plants after the salinity challenge. These findings demonstrated that strains H19-1 and H20-5 induced ABA-independent and -dependent salinity tolerance, respectively, in tomato plants, therefore these strains can be used as effective bio-fertilizers for sustainable agriculture.


Assuntos
Bacillus/fisiologia , Lycopersicon esculentum/fisiologia , Reguladores de Crescimento de Planta/farmacologia , Tolerância ao Sal/efeitos dos fármacos , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Fertilizantes , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Prolina/metabolismo , Estresse Salino
8.
J Agric Food Chem ; 67(26): 7390-7398, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31244202

RESUMO

Wound-induced suberization is an essentially protective healing process for wounded fruit to reduce water loss and microbial infection. It has been demonstrated that abscisic acid (ABA) could promote wound suberization, but the molecular mechanism of ABA regulation remains little known. In this study, the transcript level of Achn030011 (designated as AchnKCS), coding a ß-ketoacyl-coenzyme A synthase (KCS) involved in suberin biosynthesis, was found to be significantly upregulated by ABA in wounded kiwifruit. A bZIP transcription factor (Achn270881), a possible downstream transcription factor in the ABA signaling pathway, was screened and designated as AchnbZIP12 according to its homology with related Arabidopsis transcription factors. A yeast one-hybrid assay demonstrated that AchnbZIP12 could interact with the AchnKCS promoter. Furthermore, significant trans-activation of AchnbZIP12 on AchnKCS was verified. The transcript level of AchnbZIP12 was also upregulated upon treatment with ABA. These results imply that AchnbZIP12 acts as a positive regulator in ABA-mediated AchnKCS transcription during wound suberization of kiwifruit.


Assuntos
Ácido Abscísico/farmacologia , Actinidia/efeitos dos fármacos , Actinidia/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/genética , Actinidia/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Frutas/efeitos dos fármacos , Frutas/genética , Frutas/fisiologia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos
9.
J Chem Ecol ; 45(7): 598-609, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218595

RESUMO

Insect herbivory induces plant defense responses that are often modulated by components in insect saliva, oral secretions or regurgitant, frass, or oviposition fluids. These secretions contain proteins and small molecules that act as elicitors or effectors of plant defenses. Several non-protein elicitors have been identified from insect oral secretions, whereas studies of insect saliva have focused mainly on protein identification. Yet, insect saliva may also contain non-protein molecules that could activate defense responses in plants. The goal of this study was to identify non-protein plant defense elicitors present in insect saliva. We used the fall armyworm (FAW), Spodoptera frugiperda and its host plants tomato, maize, and rice as a model system. We tested the effect of protein-digested saliva or non-protein components on herbivore-induced defense responses in maize, rice and tomato. We identified phytohormones in FAW saliva using high performance liquid chromatography coupled with mass spectrometry. The results of this study show that non-protein components in FAW saliva modulated defense responses in different plant species. The saliva of this insect contains benzoic acid, and the phytohormones jasmonic acid, salicylic acid, and abscisic acid at concentrations of <5 ng per µl of saliva. Plant treatment with similar phytohormone quantities detected in FAW saliva upregulated the expression of a maize proteinase inhibitor gene in maize, and down-regulated late herbivore-induced defenses in tomato plants. We conclude that FAW saliva is a complex fluid that, in addition to known enzymatic plant defense elicitors, contains phytohormones and other small molecules.


Assuntos
Reguladores de Crescimento de Planta/análise , Saliva/química , Zea mays/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Herbivoria , Larva/metabolismo , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/parasitologia , Espectrometria de Massas , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saliva/metabolismo , Spodoptera/crescimento & desenvolvimento , Zea mays/parasitologia
10.
J Chem Ecol ; 45(7): 638-648, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31227972

RESUMO

Although the production of phytohormones has been commonly associated with production of plant defence and stress-related traits, few studies have simultaneously investigated this phenomenon across several plant species that grow along large-scale ecological gradients. To address these knowledge gaps, we performed a common garden experiment with six Cardamine species, which collectively encompass an elevational gradient of 2000 m. We quantified constitutive and Pieris brassicae caterpillars-induced phytohormones and chemical defences in leaves. We found a correlated expression of phytohormone production and the subsequent induction of chemical defences, and this correlated expression reduced herbivore performance. Furthermore, we found that abiotic conditions associated with the optimal elevation range of each species influenced the production of phytohormones and chemical defences, as well as plant growth and productivity. In particular, we found that plant species adapted to milder abiotic conditions at low elevations grew faster, were more productive and produced greater levels of chemical defences. In contrast, plant species adapted to harsher abiotic conditions at high elevations tended to produce greater levels of defence-related oxylipins. Overall, these findings highlight the importance of disentangling the role of phytohormones in mediating plant adaptations to shifting biotic and abiotic conditions.


Assuntos
Cardamine/química , Glucosinolatos/química , Himenópteros/fisiologia , Reguladores de Crescimento de Planta/química , Animais , Cardamine/metabolismo , Cromatografia Líquida de Alta Pressão , Glucosinolatos/farmacologia , Herbivoria , Interações Hospedeiro-Parasita/efeitos dos fármacos , Himenópteros/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/fisiologia , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectrometria de Massas em Tandem
11.
Plant Mol Biol ; 101(1-2): 95-112, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31236845

RESUMO

KEY MESSAGE: Sorghum glycine rich proline rich protein (SbGPRP1) exhibit antimicrobial properties and play a crucial role during biotic stress condition. Several proteins in plants build up the innate immune response system in plants which get triggered during the occurrence of biotic stress. Here we report the functional characterization of a glycine-rich proline-rich protein (SbGPRP1) from Sorghum which was previously demonstrated to be involved in abiotic stresses. Expression studies carried out with SbGPRP1 showed induced expression upon application of phytohormones like salicylic acid which might be the key in fine-tuning the expression level. Upon challenging the Sorghum plants with a compatible pathogen the SbGprp1 transcript was found to be upregulated. SbGPRP1 encodes a 197 amino acid polypeptide which was bacterially-expressed and purified for in vitro assays. Gram-positive bacteria like Bacillus and phytopathogen Rhodococcus fascians showed inhibited growth in the presence of the protein. The NPN assay, electrolytic leakage and SEM analysis showed membrane damage in bacterial cells. Ectopic expression of SbGPRP1 in tobacco plants led to enhanced tolerance towards infection caused by R. fascians. Though the N-terminal part of the protein showed disorderness the C-terminal end was quite capable of forming several α-helices which was correlated with CD spectroscopic analysis. Here, we have tried to determine the structural model for the protein and predicted the association of antimicrobial activity with the C-terminal region of the protein.


Assuntos
Anti-Infecciosos/metabolismo , Doenças das Plantas/imunologia , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacologia , Sorghum/genética , Bacillus/efeitos dos fármacos , Expressão Ectópica do Gene , Glicina/metabolismo , Filogenia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Prolina/metabolismo , Rhodococcus/efeitos dos fármacos , Sorghum/imunologia , Sorghum/metabolismo , Sorghum/microbiologia , Estresse Fisiológico , Tabaco/genética , Tabaco/imunologia , Tabaco/metabolismo , Tabaco/microbiologia
12.
Environ Sci Pollut Res Int ; 26(22): 23192-23197, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187379

RESUMO

Soil alkalinity caused by salts, such as sodium bicarbonate (NaHCO3), and the frequently associated waterlogging problems are pervasive in agriculture and have a deleterious impact on crop production. However, various plant growth regulators, including brassinosteroids, are considered to be important against different abiotic stresses experienced by plants due to drought, salinity, and heavy metal stress. We investigated the putative role of 24-epibrassinolide (EBL), an active brassinosteroid, on red rice plants experiencing alkaline stress. Seedlings were pre-treated with 0.01 µM EBL for 30 min and later, exposed to NaHCO3 (25 mM) and were sampled, 5 days after treatments. Results showed that the pre-treatment of seedlings with EBL under non-stress conditions could promote rice plant growth. Growth parameters including dry weight (DW), root and coleoptile lengths were reduced under alkaline stress, whereas EBL application reduced the level of inhibition, as compared with NaHCO3 treatment. Enhanced levels of malondialdehyde content, hydrogen peroxide, and superoxide radicals were significantly diminished by EBL pre-treatment. Moreover, pre-treatment of EBL to alkaline-treated rice seedlings largely stimulated the enzymatic activities of ascorbate peroxidase, catalase, and superoxide dismutase. Thus, the results suggest that pre-application of EBL significantly ameliorates alkaline stress in rice.


Assuntos
Ascorbato Peroxidases/química , Brassinosteroides/farmacologia , Catalase/metabolismo , Oryza/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Plântula/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Ascorbato Peroxidases/metabolismo , Peróxido de Hidrogênio/química , Malondialdeído/química , Plântula/efeitos dos fármacos , Esteroides Heterocíclicos , Superóxido Dismutase/química
13.
BMC Plant Biol ; 19(1): 219, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31132986

RESUMO

BACKGROUND: Mature fruit cracking during the normal season in African Pride (AP) atemoya is a major problem in postharvest storage. Our current understanding of the molecular mechanism underlying fruit cracking is limited. The aim of this study was to unravel the role starch degradation and cell wall polysaccharide metabolism in fruit ripening and cracking after harvest through transcriptome analysis. RESULTS: Transcriptome analysis of AP atemoya pericarp from cracking fruits of ethylene treatments and controls was performed. KEGG pathway analysis revealed that the starch and sucrose metabolism pathway was significantly enriched, and approximately 39 DEGs could be functionally annotated, which included starch, cellulose, pectin, and other sugar metabolism-related genes. Starch, protopectin, and soluble pectin contents among the different cracking stages after ethylene treatment and the controls were monitored. The results revealed that ethylene accelerated starch degradation, inhibited protopectin synthesis, and enhanced the soluble pectin content, compared to the control, which coincides with the phenotype of ethylene-induced fruit cracking. Key genes implicated in the starch, pectin, and cellulose degradation were further investigated using RT-qPCR analysis. The results revealed that alpha-amylase 1 (AMY1), alpha-amylase 3 (AMY3), beta-amylase 1 (BAM1), beta-amylase 3 (BAM3), beta-amylase 9 (BAM9), pullulanase (PUL), and glycogen debranching enzyme (glgX), were the major genes involved in starch degradation. AMY1, BAM3, BAM9, PUL, and glgX all were upregulated and had higher expression levels with ethylene treatment compared to the controls, suggesting that ethylene treatment may be responsible for accelerating starch degradation. The expression profile of alpha-1,4-galacturonosyltransferase (GAUT) and granule-bound starch synthase (GBSS) coincided with protopectin content changes and could involve protopectin synthesis. Pectinesterase (PE), polygalacturonase (PG), and pectate lyase (PEL) all involved in pectin degradation; PE was significantly upregulated by ethylene and was the key enzyme implicated pectin degradation. CONCLUSION: Both KEGG pathway enrichment analysis of DEGs and material content analysis confirmed that starch decomposition into soluble sugars and cell wall polysaccharides metabolism are closely related to the ripening and cracking of AP atemoya. A link between gene up- or downregulation during different cracking stages of atemoya fruits and how their expression affects starch and pectin contents were established by RT-qPCR analysis.


Assuntos
Annona/genética , Etilenos/farmacologia , Frutas/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/farmacologia , Polissacarídeos/metabolismo , Annona/metabolismo , Etilenos/administração & dosagem , Frutas/genética , Frutas/metabolismo , Perfilação da Expressão Gênica , Genes de Plantas , Redes e Vias Metabólicas/genética
14.
Plant Biol (Stuttg) ; 21(5): 796-804, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31081576

RESUMO

Thellungiella salsuginea is highly tolerant to abiotic stress, while its a close relative Arabidopsis thaliana is sensitive to stress. This characteristic makes T. salsuginea an excellent model for uncovering the mechanisms of abiotic stress tolerance. Abscisic acid (ABA) plays essential roles in plant abiotic and biotic stress tolerance. To test the changes in gene expression of T. salsuginea under ABA treatment, in this study, the transcriptomes of T. salsuginea roots and leaves were compared in response to exogenously application of ABA. The results showed that ABA treatment caused different expression of 2,200 and 3,305 genes in leaves and roots, respectively, compared with the untreated control. In particular, genes encoding transcription factors such as WRKY, MYB, NAC, GATA, ethylene-responsive factors (ERFs), heat stress transcription factors, basic helix-loop-helix, PLATZ and B3 domain-containing family members were enriched. In addition, 49 and 114 differentially expressed genes were identified as ABA-regulated genes, separately in leaves and roots, respectively, which were related to biotic and abiotic stresses. The expression levels of some genes were validated by qRT-PCR. Different responses of genes to ABA treatment were discovered in T. salsuginea and A. thaliana. This transcriptome analysis expands our understanding of the role of ABA in stress tolerance in T. salsuginea. Our study provides a wealth of information for improving stress tolerance in crop plants.


Assuntos
Brassicaceae/fisiologia , Ácido Abscísico/farmacologia , Brassicaceae/genética , Brassicaceae/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta/genética , Sequenciamento de Nucleotídeos em Larga Escala , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , RNA de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico , Fatores de Transcrição/metabolismo
15.
J Microbiol Biotechnol ; 29(7): 1096-1103, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31091866

RESUMO

UCB-1 is the commercial rootstock of pistachio. Reproduction of this rootstock by tissue culture is limited by low levels of proliferation rate. Therefore, any compound that improves the proliferation rate and the quality of the shoots can be used in the process of commercial reproduction of this rootstock. Use of plant growth-promoting bacteria is one of the best ideas. Given the beneficial effects of nanoparticles in enhancement of the growth in plant tissue cultures, the aim of the present study was to investigate the effects of nanoencapsulation of plant growth-promoting rhizobacteria (using silica nanoparticles and carbon nanotubes) and their metabolites in improving UCB1 pistachio micropropagation. The experiment was conducted in a completely randomized design with three replications. Before planting, treatments on the DKW medium were added. The results showed that the use of Pseudomonas fluorescens VUPF5 and Bacillus subtilis VRU1 nanocapsules significantly enhanced the root length and proliferation. The nanoformulation of the VUPF5 metabolite led to the highest root length (6.26 cm) and the largest shoot (3.34 cm). Inoculation of explants with the formulation of the metabolites (both bacterial strains) significantly elevated the average shoot length and the fresh weight of plant compared to the control. The explants were dried completely using both bacterial strains directly and with capsule coating after the three days.


Assuntos
Alginatos/química , Nanopartículas/química , Nanotubos de Carbono/química , Pistacia , Reguladores de Crescimento de Planta/química , Raízes de Plantas/crescimento & desenvolvimento , Dióxido de Silício/química , Bacillus subtilis/química , Bacillus subtilis/metabolismo , Ácidos Indolacéticos/química , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/efeitos dos fármacos , Pseudomonas fluorescens/química , Pseudomonas fluorescens/metabolismo , Microbiologia do Solo
16.
Plant Physiol Biochem ; 141: 51-59, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128563

RESUMO

Brassinosteroids (BRs) play a crucial role in improving plant resistance to various environmental stresses. In this study, we aimed to explore the potential role of BRs in protecting plants from antimony (Sb) toxicity. In the in vitro agar-plate culture experiments, the level changes of BR in wide-type plants and BR biosynthesis mutant dwrf4-1 significantly affected the corresponding response of Arabidopsis to Sb stress. Increasing the BR content significantly enhanced Sb-induced root growth inhibition and lowering the BR level appeared to reduce the plant sensitivity to Sb stress. Foliar application of eBL, however, significantly decreased the Sb accumulation and peroxidation of membrane lipids, increased the contents of chlorophyll and proline, and further boosted and strengthened the antioxidant enzymes activities. These experiments demonstrated that BRs played an important role in regulating heavy metal stress responses in plants and exogenous foliar spray of eBL was an important method for alleviating toxicity of Sb.


Assuntos
Antimônio/química , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Brassinosteroides/química , Estresse Fisiológico/efeitos dos fármacos , Antioxidantes/química , Proteínas de Arabidopsis/genética , Biodegradação Ambiental , Brassinosteroides/farmacologia , Clorofila/química , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/química , Hidroponia , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Metais Pesados/química , Estresse Oxidativo , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/farmacologia , Prolina/química
17.
BMC Genomics ; 20(1): 390, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109305

RESUMO

BACKGROUND: Phytohormones are key regulators of plant growth, development, and signalling networks involved in responses to diverse biotic and abiotic stresses. Transcriptional reference maps of hormone responses have been reported for several model plant species such as Arabidopsis thaliana, Oryza sativa, and Brachypodium distachyon. However, because of species differences and the complexity of the wheat genome, these transcriptome data are not appropriate reference material for wheat studies. RESULTS: We comprehensively analysed the transcriptomic responses in wheat spikes to seven phytohormones, including indole acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA), ethylene (ET), cytokinin (CK), salicylic acid (SA), and methyl jasmonic acid (MeJA). A total of 3386 genes were differentially expressed at 24 h after the hormone treatments. Furthermore, 22.7% of these genes exhibited overlapping transcriptional responses for at least two hormones, implying there is crosstalk among phytohormones. We subsequently identified genes with expression levels that were significantly and differentially induced by a specific phytohormone (i.e., hormone-specific responses). The data for these hormone-responsive genes were then compared with the transcriptome data for wheat spikes exposed to biotic (Fusarium head blight) and abiotic (water deficit) stresses. CONCLUSION: Our data were used to develop a transcriptional reference map of hormone responses in wheat spikes.


Assuntos
Reguladores de Crescimento de Planta/farmacologia , Transcriptoma , Triticum/genética , Desidratação/genética , Desidratação/metabolismo , Flores/efeitos dos fármacos , Flores/genética , Flores/metabolismo , Fusarium , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma/efeitos dos fármacos , Triticum/efeitos dos fármacos , Triticum/metabolismo , Triticum/microbiologia
18.
Planta ; 250(1): 347-366, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31037486

RESUMO

MAIN CONCLUSION: The involvement of a WRKY transcription factor in the regulation of lignan biosynthesis in flax using a hairy root system is described. Secoisolariciresinol is the main flax lignan synthesized by action of LuPLR1 (pinoresinol-lariciresinol reductase 1). LuPLR1 gene promoter deletion experiments have revealed a promoter region containing W boxes potentially responsible for the response to Fusarium oxysporum. W boxes are bound by WRKY transcription factors that play a role in the response to stress. A candidate WRKY transcription factor, LuWRKY36, was isolated from both abscisic acid and Fusarium elicitor-treated flax cell cDNA libraries. This transcription factors contains two WRKY DNA-binding domains and is a homolog of AtWRKY33. Different approaches confirmed LuWRKY36 binding to a W box located in the LuPLR1 promoter occurring through a unique direct interaction mediated by its N-terminal WRKY domain. Our results propose that the positive regulator action of LuWRKY36 on the LuPLR1 gene regulation and lignan biosynthesis in response to biotic stress is positively mediated by abscisic acid and inhibited by ethylene. Additionally, we demonstrate a differential Fusarium elicitor response in susceptible and resistant flax cultivars, seen as a faster and stronger LuPLR1 gene expression response accompanied with higher secoisolariciresinol accumulation in HR of the resistant cultivar.


Assuntos
Linho/genética , Fusarium/fisiologia , Lignanas/biossíntese , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Planta/farmacologia , Fatores de Transcrição/metabolismo , Ácido Abscísico/farmacologia , Etilenos/farmacologia , Linho/metabolismo , Linho/microbiologia , Biblioteca Gênica , Modelos Biológicos , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Regiões Promotoras Genéticas/genética , Estresse Fisiológico , Fatores de Transcrição/genética
19.
Planta ; 250(1): 381-390, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31062160

RESUMO

MAIN CONCLUSION: Ethylene receptor is crucial for PCD and aerenchyma formation in Typha angustifolia leaves. Not only does it receive and deliver the ethylene signal, but it probably can determine the cell fate during aerenchyma morphogenesis, which is due to the receptor expression quantity. Aquatic plant oxygen delivery relies on aerenchyma, which is formed by a programmed cell death (PCD) procedure. However, cells in the outer edge of the aerenchyma (palisade cells and septum cells) remain intact, and the mechanism is unclear. Here, we offer a hypothesis: cells that have a higher content of ethylene receptors do not undergo PCD. In this study, we investigated the leaf aerenchyma of the aquatic plant Typha angustifolia. Ethephon and pyrazinamide (PZA, an inhibitor of ACC oxidase) were used to confirm that ethylene is an essential hormone for PCD of leaf aerenchyma cells in T. angustifolia. That the ethylene receptor was an indispensable factor in this PCD was confirmed by 1-MCP (an inhibitor of the ethylene receptor) treatment. Although PCD can be avoided by blocking the ethylene receptor, excessive ethylene receptors also protect cells from PCD. TaETR1, TaETR2 and TaEIN4 in the T. angustifolia leaf were detected by immunofluorescence (IF) using polyclonal antibodies. The result showed that the content of ethylene receptors in PCD-unsusceptible cells was 4-14 times higher than that one in PCD-susceptible cells, suggesting that PCD-susceptible cells undergo the PCD programme, while PCD-unsusceptible cells do not due to the content difference in the ethylene receptor in different cells. A higher level of ethylene receptor content makes the cells insensitive to ethylene, thereby avoiding cell death and degradation.


Assuntos
Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Typhaceae/fisiologia , Aminoácido Oxirredutases/antagonistas & inibidores , Apoptose/genética , Diferenciação Celular/genética , Ciclopropanos/farmacologia , Etilenos/metabolismo , Compostos Organofosforados/farmacologia , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética , Pirazinamida/farmacologia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/genética , Typhaceae/efeitos dos fármacos , Typhaceae/enzimologia , Typhaceae/crescimento & desenvolvimento
20.
BMC Plant Biol ; 19(1): 191, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072335

RESUMO

BACKGROUND: BRASSINAZOLE-RESISTANT (BZR) family genes encode plant-specific transcription factors (TFs) that participate in brassinosteroid signal transduction. BZR TFs have vital roles in plant growth, including cell elongation. However, little is known about BZR genes in sugar beet (Beta vulgaris L.). RESULTS: Therefore, we performed a genome-wide investigation of BvBZR genes in sugar beet. Through an analysis of the BES1_N conserved domain, six BvBZR gene family members were identified in the sugar beet genome, which clustered into three subgroups according to a phylogenetic analysis. Each clade was well defined by the conserved motifs, implying that close genetic relationships could be identified among the members of each subfamily. According to chromosomal distribution mapping, 2, 1, 1, 1, and 1 genes were located on chromosomes 1, 4, 5, 6, and 8, respectively. The cis-acting elements related to taproot growth were randomly distributed in the promoter sequences of the BvBZR genes. Tissue-specific expression analyses indicated that all BvBZR genes were expressed in all three major tissue types (roots, stems, and leaves), with significantly higher expression in leaves. Subcellular localization analysis revealed that Bv1_fxre and Bv6_nyuw are localized in the nuclei, consistent with the prediction of Wolf PSORT. CONCLUSION: These findings offer a basis to predict the functions of BZR genes in sugar beet, and lay a foundation for further research of the biological functions of BZR genes in sugar beet.


Assuntos
Beta vulgaris/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Fatores de Transcrição/genética , Motivos de Aminoácidos , Beta vulgaris/efeitos dos fármacos , Cromossomos de Plantas/genética , Sequência Conservada/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Proteínas de Fluorescência Verde/metabolismo , Motivos de Nucleotídeos/genética , Filogenia , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo
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