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1.
Gene ; 849: 146906, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162526

RESUMO

NAC transcription factors (TFs) play an important role in the plant resistant response to biotic and abiotic stresses. However, the functions of the most NAC TFs are still unknown, especially in tomato. Here, we identified and functionally characterized an NAC TFs, SlNAP1, in tomato, and found that SlNAP1 was significantly induced by salt stress. Under 150 mM NaCl treatments, morphological indexes of SlNAP1 over-expressed (SlNAP1-OE) transgenic tomato lines were significantly better than the wild-type (WT) plants. The content of Na+ in leaves and roots of SlNAP1-OE transgenic plants decreased, while the K+ content in leaves, roots, and stems increased compared with WT plants. The expression of the salt stress-related genes (NHX1, HKT1;2 and SOS1) in SlNAP1-OE plants were also significantly up-regulated under salt stress. The SOD, POD and CAT activities and the expression level of antioxidant oxidase synthesis genes of SlNAP1-OE lines were significantly increased. In addition, the SlNAP1-OE lines accumulated less MDA, H2O2 and O2•-, improved antioxidant defense systems which contributed to increase salt tolerance. In summary, our data suggest that SlNAP1 positively regulates salt tolerance in tomato by regulating ion homeostasis and ROS metabolism.


Assuntos
Lycopersicon esculentum , Tolerância ao Sal , Tolerância ao Sal/genética , Lycopersicon esculentum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação da Expressão Gênica de Plantas , Antioxidantes , Peróxido de Hidrogênio/metabolismo , Cloreto de Sódio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Homeostase , Oxirredutases/genética , Superóxido Dismutase/genética
2.
J Hazard Mater ; 443(Pt A): 130212, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36308936

RESUMO

Pesticide overuse has led to serious global concerns regarding food safety and environmental pollution. Although the reduction of pesticide residue is critical, our knowledge about induced pesticide metabolism in plants remains fragmentary. Melatonin (N-acetyl-5-methoxytryptamine) is an effective stress-relieving agent in both animals and plants, but little is known about the melatonin signaling mechanism and its effect on pesticide metabolism in plants. Here, we found that exogenous melatonin treatment significantly reduced chlorothalonil residue by 41 % but suppression of endogenous melatonin accumulation increased chlorothalonil residue in tomato leaves. Moreover, melatonin increased photosynthesis, Fv/Fm, Calvin cycle enzyme activity, antioxidant enzyme activity, glutathione pool, and RESPIRATORY BURST HOMOLOG1 (RBOH1) expression in tomato leaves. However, the upregulation of RBOH1, CYP724B2, GST1, GST2, GSH and ABC, the increased glutathione concentrations and the activity of detoxification enzymes due to melatonin treatment were all significantly attenuated by the treatment with an NADPH oxidase inhibitor and a ROS scavenger, indicating a clear relationship between the reduction of pesticide residue and induction in detoxifying enzymes and genes upon melatonin treatment in an apoplastic H2O2-dependent manner. These results reveal that melatonin-induced reduction in chlorothalonil residue is mediated by H2O2 signaling in tomato leaves.


Assuntos
Lycopersicon esculentum , Melatonina , Resíduos de Praguicidas , Praguicidas , Lycopersicon esculentum/metabolismo , Melatonina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/metabolismo , Resíduos de Praguicidas/metabolismo , Folhas de Planta/metabolismo , Antioxidantes/metabolismo , Glutationa/metabolismo , Praguicidas/metabolismo
3.
Food Chem ; 402: 134217, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36116275

RESUMO

In this study, tomato seed oil conventional emulsion (7 µm) and nanoemulsion (0.146 µm) with desirable stability were prepared, then the effect of tomato seed oil addition (bulk and emulsified forms) and thermal treatment on properties of tomato juice was evaluated. Tomato juice without oil and heat treatment exhibited the lowest bioaccessibility of lycopene (17.8 %). Incorporation of oil and applying heat treatment significantly increased the extent of lipid digestion and bioaccessibility of lycopene. In this regard, the nanoemulsion had the highest bioaccessibility (44.85 %) compared to conventional emulsion (33.90 %) and bulk oil (27.11 %), due to the smaller oil droplets. The oxidative stability of oil in heat-treated tomato juice samples decreased during 28 days of storage at 4 °C, whereas the nanoemulsion exhibited the highest peroxide value (4.43 meq O2/kg of oil) compared to conventional emulsion and bulk oil (3.91 and 3.49 meq O2/kg of oil, respectively) at the end of the period.


Assuntos
Lycopersicon esculentum , Licopeno/metabolismo , Lycopersicon esculentum/metabolismo , Carotenoides/análise , Emulsões/metabolismo , Temperatura Alta , Manipulação de Alimentos , Óleos Vegetais/metabolismo , Peróxidos/metabolismo , Estresse Oxidativo , Lipídeos
4.
Sci Rep ; 12(1): 18363, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319664

RESUMO

The plant apoplast has a crucial role in photosynthesis and respiration due to its vital function in gas exchange and transpiration. The apoplast is also a dynamic environment that participates in many ion and nutrient transport processes via plasma membrane-localized proteins. Furthermore, diverse microbes colonize the plant apoplast, including the hemibiotrophic bacterial pathogen, Pseudomonas syringae pv. tomato (Pto) strain DC3000. Pto DC3000 initiates pathogenesis upon moving through stomata into the apoplast and then proliferating to high levels. Here we developed a centrifugation-based method to isolate and quantify the apoplast fluid in Arabidopsis leaves, without significantly damaging the tissue. We applied the simple apoplast extraction method to demonstrate that the Pto DC3000 type III bacterial effectors AvrE1 and HopM1 induce hydration of the Arabidopsis apoplast in advance of macroscopic water-soaking, disruption of host cell integrity, and disease progression. Finally, we demonstrate the utility of the apoplast extraction method for isolation of bacteria proliferating in the apoplast.


Assuntos
Arabidopsis , Lycopersicon esculentum , Pseudomonas syringae/metabolismo , Arabidopsis/metabolismo , Água , Doenças das Plantas/microbiologia , Virulência , Lycopersicon esculentum/metabolismo , Folhas de Planta/metabolismo , Proteínas de Bactérias/metabolismo
5.
Stem Cell Res Ther ; 13(1): 515, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371298

RESUMO

Tendon regeneration is difficult because detailed knowledge about tendon progenitor cells (TPCs), which produce tenocytes to repair tendon tissue, has not been revealed. Mohawk homeobox (MKX) is a marker of TPCs or tenocytes, but a human pluripotent stem cell (hPSC)-based reporter system that visualizes MKX+ cells has not been developed. Here, we established an hPSC-derived MKX-tdTomato reporter cell line and tested the induction ratio of MKX-tdTomato+ cells using our stepwise/xeno-free differentiation protocol. MKX-tdTomato+ cells were generated with high efficiency and expressed tendon-specific markers, including MKX, SCX, TNMD, and COL1A1. Our MKX-tdTomato hPSC line would be a useful tool for studying the development or regeneration of tendon tissue.


Assuntos
Lycopersicon esculentum , Células-Tronco Pluripotentes , Humanos , Lycopersicon esculentum/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Diferenciação Celular , Tendões/metabolismo , Células-Tronco Pluripotentes/metabolismo
6.
BMC Genomics ; 23(1): 756, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396987

RESUMO

BACKGROUND: In eukaryotes, cell-to-cell communication relies on the activity of small signaling peptides. In plant genomes, many hundreds of genes encode for such short peptide signals. However, only few of them are functionally characterized and due to the small gene size and high sequence variability, the comprehensive identification of such peptide-encoded genes is challenging. The CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION-RELATED (CLE) gene family encodes for short peptides that have a role in plant meristem maintenance, vascular patterning and responses to environment. The full repertoire of CLE genes and the role of CLE signaling in tomato (Solanum lycopersicum)- one of the most important crop plants- has not yet been fully studied. RESULTS: By using a combined approach, we performed a genome-wide identification of CLE genes using the current tomato genome version SL 4.0. We identified 52 SlCLE genes, including 37 new non annotated before. By analyzing publicly available RNAseq datasets we could confirm the expression of 28 new SlCLE genes. We found that SlCLEs are often expressed in a tissue-, organ- or condition-specific manner. Our analysis shows an interesting gene diversification within the SlCLE family that seems to be a result of gene duplication events. Finally, we could show a biological activity of selected SlCLE peptides in the root growth arrest that was SlCLV2-dependent. CONCLUSIONS: Our improved combined approach revealed 37 new SlCLE genes. These findings are crucial for better understanding of the CLE signaling in tomato. Our phylogenetic analysis pinpoints the closest homologs of Arabidopsis CLE genes in tomato genome and can give a hint about the function of newly identified SlCLEs. The strategy described here can be used to identify more precisely additional short genes in plant genomes. Finally, our work suggests that the mechanism of root-active CLE peptide perception is conserved between Arabidopsis and tomato. In conclusion, our work paves the way to further research on the CLE-dependent circuits modulating tomato development and physiological responses.


Assuntos
Arabidopsis , Lycopersicon esculentum , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Peptídeos/genética , Peptídeos/metabolismo , Genômica
7.
BMC Plant Biol ; 22(1): 536, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396998

RESUMO

BACKGROUND: In nature and in cultivated fields, plants encounter multiple stress factors. Nonetheless, our understanding of how plants actively respond to combinatorial stress remains limited. Among the least studied stress combination is that of flooding and herbivory, despite the growing importance of these stressors in the context of climate change. We investigated plant chemistry and gene expression changes in two heirloom tomato varieties: Cherokee Purple (CP) and Striped German (SG) in response to flooding, herbivory by Spodoptera exigua, and their combination. RESULTS: Volatile organic compounds (VOCs) identified in tomato plants subjected to flooding and/or herbivory included several mono- and sesquiterpenes. Flooding was the main factor altering VOCs emission rates, and impacting plant biomass accumulation, while different varieties had quantitative differences in their VOC emissions. At the gene expression levels, there were 335 differentially expressed genes between the two tomato plant varieties, these included genes encoding for phenylalanine ammonia-lyase (PAL), cinnamoyl-CoA-reductase-like, and phytoene synthase (Psy1). Flooding and variety effects together influenced abscisic acid (ABA) signaling genes with the SG variety showing higher levels of ABA production and ABA-dependent signaling upon flooding. Flooding downregulated genes associated with cytokinin catabolism and general defense response and upregulated genes associated with ethylene biosynthesis, anthocyanin biosynthesis, and gibberellin biosynthesis. Combining flooding and herbivory induced the upregulation of genes including chalcone synthase (CHS), PAL, and genes encoding BAHD acyltransferase and UDP-glucose iridoid glucosyltransferase-like genes in one of the tomato varieties (CP) and a disproportionate number of heat-shock proteins in SG. Only the SG variety had measurable changes in gene expression due to herbivory alone, upregulating zeatin, and O-glucosyltransferase and thioredoxin among others. CONCLUSION: Our results suggest that both heirloom tomato plant varieties differ in their production of secondary metabolites including phenylpropanoids and terpenoids and their regulation and activation of ABA signaling upon stress associated with flooding. Herbivory and flooding together had interacting effects that were evident at the level of plant chemistry (VOCs production), gene expression and biomass markers. Results from our study highlight the complex nature of plant responses to combinatorial stresses and point at specific genes and pathways that are affected by flooding and herbivory combined.


Assuntos
Lycopersicon esculentum , Compostos Orgânicos Voláteis , Herbivoria , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Plantas/genética , Compostos Orgânicos Voláteis/metabolismo , Glucosiltransferases/genética , Expressão Gênica
8.
Cells ; 11(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36359833

RESUMO

The effect of red (RL, 660 nm) and blue (BL, 450 nm) light on phy mutant tomato plants was studied. The rates of photosynthesis (Pn) and transpiration, the efficiency of the primary photochemical processes of photosynthesis, the contents of flavonoids and phenolic compounds, the low-molecular-weight antioxidant capacity (Trolox equivalent antioxidant capacity (TEAC)) of leaf extracts, and the expression of light-dependent genes were evaluated. Under RL, BL, and white fluorescent light (WFL), the Pn values decreased in the order: WT > phyb2 > phyaphyb2 > phyaphyb1phyb2, except for the Pn in phyb2 on BL. Phyb2 also had a larger number of stomata under BL and, as a result, it reached maximum transpiration. The noticeable accumulation of flavonoids and phenolic compounds was observed only in the phyb2 and phyaphyb2 mutants upon irradiation with BL, which agrees with the increased TEAC in the leaf extracts. We suggest that the increased antioxidant activity under PHYB2 deficiency and the maintenance of high photosynthesis under BL are based on an increase in the expression of the early signaling transcription factors genes BBX, HY5. The largest decrease in the content of flavonoids and TEAC was manifested with a deficiency in PHYB1, which is probably the key to maintaining the antioxidant status in BL plants.


Assuntos
Lycopersicon esculentum , Fitocromo , Fitocromo/genética , Fitocromo/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Flavonoides , Antioxidantes/metabolismo , Fotossíntese/genética , Extratos Vegetais/metabolismo
9.
Plant Physiol Biochem ; 193: 139-152, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36356545

RESUMO

High salinity and drought stresses often cause plants to produce ROS, including hydrogen peroxide (H2O2) and superoxide (O2-), which interfere with plant growth and affect crop yield. The transcription factors of the MYB family are involved in responses to biotic and abiotic stresses. Here, we isolated the R2R3-MYB transcription factor gene SlMYB50 and found that silencing of SlMYB50 increased resistance to PEG 6000, mannitol and salt. In addition, the resistance of transgenic tomatoes increased under high salt and drought stress. After stress treatment, the relative water content, chlorophyll content (critical for carbon fixation) and root vitality of the SlMYB50-RNAi lines were higher than those of the wild-type (WT). The opposite was true the water loss rate, relative conductivity, and MDA (as a sign of cell wall disruption). Under drought stress conditions, SlMYB50-silenced lines exhibited less H2O2 and less O2- accumulation, as well as higher CAT enzyme activity, than were exhibited by the WT. Notably, after stress treatment, the expression levels of chlorophyll-synthesis-related, flavonoid-synthesis-related, carotenoid-related, antioxidant-enzyme-related and ABA-biosynthesis-related genes were all upregulated in SlMYB50-silenced lines compared to those of WT. A dual-luciferase reporter system was used to verify that SlMYB50 could bind to the CHS1 promoter. In summary, this study identified essential roles for SlMYB50 in regulating drought and salt tolerance.


Assuntos
Secas , Lycopersicon esculentum , Lycopersicon esculentum/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Peróxido de Hidrogênio/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Salino/genética , Estresse Fisiológico/genética , Clorofila , Água/metabolismo
10.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362073

RESUMO

Light quality affects plant growth and the functional component accumulation of fruits. However, there is little knowledge of the effects of light quality based on multiomics profiles. This study combined transcriptomic, ionomic, and metabolomic analyses to elucidate the effects of light quality on metabolism and gene expression in tomato fruit. Micro-Tom plants were grown under blue or red light-emitting diode light for 16 h daily after anthesis. White fluorescent light was used as a reference. The metabolite and element concentrations and the expression of genes markedly changed in response to blue and red light. Based on the metabolomic analysis, amino acid metabolism and secondary metabolite biosynthesis were active in blue light treatment. According to transcriptomic analysis, differentially expressed genes in blue and red light treatments were enriched in the pathways of secondary metabolite biosynthesis, carbon fixation, and glycine, serine, and threonine metabolism, supporting the results of the metabolomic analysis. Ionomic analysis indicated that the element levels in fruits were more susceptible to changes in light quality than in leaves. The concentration of some ions containing Fe in fruits increased under red light compared to under blue light. The altered expression level of genes encoding metal ion-binding proteins, metal tolerance proteins, and metal transporters in response to blue and red light in the transcriptomic analysis contributes to changes in the ionomic profiles of tomato fruit.


Assuntos
Lycopersicon esculentum , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Frutas/metabolismo , Transcriptoma , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica
11.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362311

RESUMO

To address the low Ca-induced growth inhibition of tomato plants, the mitigation effect of exogenous Si on tomato seedlings under low-Ca stress was investigated using different application methods. We specifically analyzed the effects of root application or foliar spraying of 1 mM Si on growth conditions, leaf photosynthetic properties, stomatal status, chlorophyll content, chlorophyll fluorescence, ATP activity and content, Calvin cycle-related enzymatic activity, and gene expression in tomato seedlings under low vs. adequate calcium conditions. We found that the low-Ca environment significantly affected (reduced) these parameters, resulting in growth limitation. Surprisingly, the application of 1 mM Si significantly increased plant height, stem diameter, and biomass accumulation, protected photosynthetic pigments, improved gas exchange, promoted ATP production, enhanced the activity of Calvin cycle key enzymes and expression of related genes, and ensured efficient photosynthesis to occur in plants under low-Ca conditions. Interestingly, when the same amount of Si was applied, the beneficial effects of Si were more pronounced under low-Ca conditions that under adequate Ca. We speculate that Si might promote the absorption and transport of calcium in plants. The effects of Si also differed depending on the application method; foliar spraying was better in alleviating photosynthetic inhibition in plants under low-Ca stress, whereas root application of Si significantly promoted root growth and development. Enhancing the photosynthetic capacity by foliar Si application is an effective strategy for ameliorating the growth inhibition of plants under low-Ca stress.


Assuntos
Lycopersicon esculentum , Plântula , Plântula/metabolismo , Lycopersicon esculentum/metabolismo , Silício/farmacologia , Silício/metabolismo , Cálcio/metabolismo , Fotossíntese , Clorofila/metabolismo , Folhas de Planta/metabolismo , Trifosfato de Adenosina/metabolismo
12.
Int J Mol Sci ; 23(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36362362

RESUMO

A momentary increase in cytoplasmic Ca2+ generates an oscillation responsible for the activation of proteins, such as calmodulin and kinases, which interact with reactive oxygen species (ROS) for the transmission of a stress signal. This study investigated the influence of variations in calcium concentrations on plant defense signaling and photosynthetic acclimatization after mechanical damage. Solanum lycopersicum Micro-Tom was grown with 0, 2 and 4 mM Ca2+, with and without mechanical damage. The expression of stress genes was evaluated, along with levels of antioxidant enzymes, hydrogen peroxide, lipid peroxidation, histochemistry, photosynthesis and dry mass of organs. The ROS production generated by mechanical damage was further enhanced by calcium-free conditions due to the inactivation of the oxygen evolution complex, contributing to an increase in reactive species. The results indicated that ROS affected mechanical damage signaling because calcium-free plants exhibited high levels of H2O2 and enhanced expression of kinase and RBOH1 genes, necessary conditions for an efficient response to stress. We conclude that the plants without calcium supply recognized mechanical damage but did not survive. The highest expression of the RBOH1 gene and the accumulation of H2O2 in these plants signaled cell death. Plants grown in the presence of calcium showed higher expression of SlCaM2 and control of H2O2 concentration, thus overcoming the stress caused by mechanical damage, with photosynthetic acclimatization and without damage to dry mass production.


Assuntos
Lycopersicon esculentum , Lycopersicon esculentum/metabolismo , Peróxido de Hidrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sinalização do Cálcio , Fotossíntese/genética , Aclimatação , Antioxidantes/metabolismo , Expressão Gênica , Folhas de Planta/metabolismo
13.
Genes (Basel) ; 13(11)2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36360252

RESUMO

NAC (NAM/ATAF/CUC) transcription factors belong to a unique gene family in plants, which play vital roles in regulating diverse biological processes, including growth, development, senescence, and in response to biotic and abiotic stresses. Tomato (Solanum lycopersicum), as the most highly valued vegetable and fruit crop worldwide, is constantly attacked by Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), causing huge losses in production. Thus, it is essential to conduct a comprehensive identification of the SlNAC genes involved in response to Pst DC3000 in tomato. In this study, a complete overview of this gene family in tomato is presented, including genome localization, protein domain architectures, physical and chemical features, and nuclear location score. Phylogenetic analysis identified 20 SlNAC genes as putative stress-responsive genes, named SSlNAC 1-20. Expression profiles analysis revealed that 18 of these 20 SSlNAC genes were significantly induced in defense response to Pst DC3000 stress. Furthermore, the RNA-seq data were mined and analyzed, and the results revealed the expression pattern of the 20 SSlNAC genes in response to Pst DC3000 during the PTI and ETI. Among them, SSlNAC3, SSlNAC4, SSlNAC7, SSlNAC8, SSlNAC12, SSlNAC17, and SSlNAC19 were up-regulated against Pst DC3000 during PTI and ETI, which suggested that these genes may participate in both the PTI and ETI pathway during the interaction between tomato and Pst DC3000. In addition, SSlNAC genes induced by exogenous hormones, including indole-3-acetic acid (IAA), abscisic acid (ABA), salicylic acid (SA), and methyl jasmonic acid (MeJA), were also recovered. These results implied that SSlNAC genes may participate in the Pst DC3000 stress response by multiple regulatory pathways of the phytohormones. In all, this study provides important clues for further functional analysis and of the regulatory mechanism of SSlNAC genes under Pst DC3000 stress.


Assuntos
Lycopersicon esculentum , Regulação da Expressão Gênica de Plantas/genética , Lycopersicon esculentum/metabolismo , Filogenia , Doenças das Plantas/genética , Transdução de Sinais/genética
14.
Sci Rep ; 12(1): 20154, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418431

RESUMO

Understanding the responses of insect herbivores to plant chemical defences is pivotal for the management of crops and pests. However, the mechanisms of interaction are not entirely understood. In this study, we compared the whole transcriptome gene expression of the aphid Macrosiphum euphorbiae grown on two different varieties of tomato that differ in their inducible chemical defences. We used two isogenic lines of tomato with a shared genetic background that only differ in the presence of type IV glandular trichomes and their associated acylsucrose excretions. This works also reports a de novo transcriptome of the aphid M. euphorbiae. Subsequently, we identified a unique and distinct gene expression profile for the first time corresponding to aphid´s exposure to type IV glandular trichomes and acylsugars. The analysis of the aphid transcriptome shows that tomato glandular trichomes and their associated secretions are highly efficient in triggering stress-related responses in the aphid, and demonstrating that their role in plant defence goes beyond the physical impediment of herbivore activity. Some of the differentially expressed genes were associated with carbohydrate, lipid and xenobiotic metabolisms, immune system, oxidative stress response and hormone biosynthesis pathways. Also, the observed responses are compatible with a starvation syndrome. The transcriptome analysis puts forward a wide range of genes involved in the synthesis and regulation of detoxification enzymes that reveal important underlying mechanisms in the interaction of the aphid with its host plant and provides a valuable genomic resource for future study of biological processes at the molecular level using this aphid.


Assuntos
Afídeos , Lycopersicon esculentum , Animais , Afídeos/genética , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Tricomas/genética , Perfilação da Expressão Gênica , Herbivoria
15.
Plant Signal Behav ; 17(1): 2139116, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36408837

RESUMO

DnaJ proteins are key molecular chaperones that act as a part of the stress response to stabilize plant proteins, thereby maintaining protein homeostasis under stressful conditions. Herein we used transgenic plants to explore the role of the tomato (Solanum lycopersicum) SlDnaJ20 chloroplast DnaJ protein in to the resistance of these proteins to cold. When chilled, transgenic plants exhibited superior cold resistance, with reduced growth inhibition and cellular damage and increased fresh mass and chlorophyll content relative to control. These transgenic plants further exhibited increased Fv/Fm, P700 oxidation, φRo, and δRo relative to control plants under chilling conditions. Under these same cold conditions, these transgenic plants also exhibited higher levels of core proteins in the photosystem I (PSI) and II (PSII) complexes (PsaA and PsaB; D1 and D2) relative to control wild-type plants. Together these results suggested that the overexpression of SlDnaJ20 is sufficient to maintain PSI and PSII complex stability and to alleviate associated photoinhibition of these complexes, thereby increasing transgenic plant resistance to cold stress.


Assuntos
Lycopersicon esculentum , Lycopersicon esculentum/metabolismo , Complexo de Proteína do Fotossistema I/genética , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Cloroplastos/genética , Cloroplastos/metabolismo , Plantas Geneticamente Modificadas/metabolismo
16.
J Biosci ; 472022.
Artigo em Inglês | MEDLINE | ID: mdl-36222142

RESUMO

Green leaf volatiles impart characteristic aroma and flavour to a variety of natural foods due to their inherent grassy note contributed by aldehydes. Hydroperoxide lyase (HPL) is an enzyme that helps in the cleavage of fatty acid hydroperoxides to short-chain aldehydes and ω-oxo-acids. A tomato hydroperoxide lyase gene was successfully expressed in E. coli BL21 (DE3) cells and used in the subsequent production of (Z)-3-hexenal. Biochemical characterization of the HPL activity exhibited by these whole cells enabled the development of a suitable one-pot reaction process for conversion of the hydroperoxide substrate to the corresponding aldehyde, (Z)-3-hexenal, and finally to (Z)-3-hexenol, a high-value flavour and fragrance ingredient.


Assuntos
Lycopersicon esculentum , Aldeído Liases , Aldeídos/metabolismo , Sistema Enzimático do Citocromo P-450 , Escherichia coli/genética , Escherichia coli/metabolismo , Peróxido de Hidrogênio , Peróxidos Lipídicos/química , Peróxidos Lipídicos/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Odorantes
18.
Food Res Int ; 161: 111491, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36192866

RESUMO

Ethylene plays a crucial role in regulating fruit ripening, quality, and defense response. However, the mechanism(s) responsible for wound-induced ethylene regulation of fruit physiology at a network level is unclear. We used mass spectrometry (MS) to identify differences in the physiological response between fresh-cut fruits of wild-type (WT) tomato and an ethylene receptor mutant (SlETR-3) (also referred to as Nr) during storage. We found that Nr mutants exhibited better appearance and quality, as well as higher ethylene levels during the first 3 d of storage at 4 °C. Thirty-seven (0 h), eighty-two (12 h) and twelve (24 h) differentially abundant proteins were identified between the fresh-cut slices of the two genotypes during storage at the designated timepoints. In particular, antioxidant enzymes, such as ascorbate peroxidase, glutathione S-transferase, and peroxiredoxin were highly expressed in WT fruit, which was associated with higher H2O2 production, and high levels of transcription of cell-wall degrading enzymes. Leucine aminopeptidase, a marker enzyme for response to wounding exhibited higher levels in the Nr mutant, which is consistent with its higher production of ethylene. Collectively, our results provide a deeper insight into the ethylene-induced physiological regulatory network that is activated in fresh-cut tomatoes.


Assuntos
Lycopersicon esculentum , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Etilenos/farmacologia , Glutationa Transferase/metabolismo , Peróxido de Hidrogênio/metabolismo , Leucil Aminopeptidase/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Peroxirredoxinas/metabolismo , Proteômica
19.
Int J Mol Sci ; 23(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36232739

RESUMO

In plants, the trehalose biosynthetic pathway plays key roles in the regulation of carbon allocation and stress adaptation. Engineering of the pathway holds great promise to increase the stress resilience of crop plants. The synthesis of trehalose proceeds by a two-step pathway in which a trehalose-phosphate synthase (TPS) uses UDP-glucose and glucose-6-phosphate to produce trehalose-6 phosphate (T6P) that is subsequently dephosphorylated by trehalose-6 phosphate phosphatase (TPP). While plants usually do not accumulate high amounts of trehalose, their genome encodes large families of putative trehalose biosynthesis genes, with many members lacking obvious enzymatic activity. Thus, the function of putative trehalose biosynthetic proteins in plants is only vaguely understood. To gain a deeper insight into the role of trehalose biosynthetic proteins in crops, we assessed the enzymatic activity of the TPS/TPP family from tomato (Solanum lycopersicum L.) and investigated their expression pattern in different tissues as well as in response to temperature shifts. From the 10 TPS isoforms tested, only the 2 proteins belonging to class I showed enzymatic activity, while all 5 TPP isoforms investigated were catalytically active. Most of the TPS/TPP family members showed the highest expression in mature leaves, and promoter-reporter gene studies suggest that the two class I TPS genes have largely overlapping expression patterns within the vasculature, with only subtle differences in expression in fruits and flowers. The majority of tomato TPS/TPP genes were induced by heat stress, and individual family members also responded to cold. This suggests that trehalose biosynthetic pathway genes could play an important role during temperature stress adaptation. In summary, our study represents a further step toward the exploitation of the TPS and TPP gene families for the improvement of tomato stress resistance.


Assuntos
Lycopersicon esculentum , Carbono , Glucose , Glucose-6-Fosfato , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Fosfatos , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Recombinantes , Temperatura , Trealose/genética , Trealose/metabolismo , Uridina Difosfato Glucose
20.
Int J Mol Sci ; 23(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36233017

RESUMO

Recent studies have confirmed that chlorophyllase (CLH), a long-found chlorophyll (Chl) dephytylation enzyme for initiating Chl catabolism, has no function in leaf senescence-related Chl breakdown. Yet, CLH is considered to be involved in fruit degreening and responds to external and hormonal stimuli. The purpose of this work was to elucidate in detail the biochemical, structural properties, and gene expression of four CLHs from the Solanum lycopersicum genome so as to understand the roles of Solanum lycopersicum chlorophyllases (SlCLHs). SlCLH1/4 were the predominantly expressed CLH genes during leaf and fruit development/ripening stages, and SlCLH1 in mature green fruit was modulated by light. SlCLH1/2/3/4 contained a highly conserved GHSXG lipase motif and a Ser-Asp-His catalytic triad. We identified Ser159, Asp226, and His258 as the essential catalytic triad by site-directed mutagenesis in recombinant SlCLH1. Kinetic analysis of the recombinant enzymes revealed that SlCLH1 had high hydrolysis activities against Chl a, Chl b, and pheophytin a (Phein a), but preferred Chl a and Chl b over Phein a; SlCLH2/3 only showed very low activity to Chl a and Chl b, while SlCLH4 showed no Chl dephytylation activity. The recombinant SlCLH1/2/3 had different pH stability and temperature optimum. Removal of the predicted N-terminal processing peptide caused a partial loss of activity in recombinant SlCLH1/2 but did not compromise SlCLH3 activity. These different characteristics among SlCLHs imply that they may have different physiological functions in tomato.


Assuntos
Lycopersicon esculentum , Hidrolases de Éster Carboxílico , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Cinética , Lipase/metabolismo , Lycopersicon esculentum/metabolismo
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