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1.
Plant Physiol ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918899

RESUMO

Population expansion is a global issue, especially for food production. Meanwhile, global climate change is damaging our soils, making it difficult for crops to thrive and lowering both production and quality. Poor nutrition and salinity stress affect plant growth and development. Although the impact of individual plant stresses has been studied for decades, the real stress scenario is more complex due to the exposure to multiple stresses at the same time. Here we investigate using existing evidence and a meta-analysis approach to determine molecular linkages between two contemporaneous abiotic stimuli, phosphate (Pi) deficiency and salinity, on a single plant cell model, the root hairs (RHs), which is the first plant cell exposed to them. Understanding how these two stresses work molecularly in RHs may help us build super-adaptable crops and sustainable agriculture in the face of global climate change.

2.
Biomolecules ; 13(5)2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-37238601

RESUMO

Among the adenylate carriers identified in Arabidopsis thaliana, only the AMP/ATP transporter ADNT1 shows increased expression in roots under waterlogging stress conditions. Here, we investigated the impact of a reduced expression of ADNT1 in A. thaliana plants submitted to waterlogging conditions. For this purpose, an adnt1 T-DNA mutant and two ADNT1 antisense lines were evaluated. Following waterlogging, ADNT1 deficiency resulted in a reduced maximum quantum yield of PSII electron transport (significantly for adnt1 and antisense Line 10), indicating a higher impact caused by the stress in the mutants. In addition, ADNT1 deficient lines showed higher levels of AMP in roots under nonstress condition. This result indicates that the downregulation of ADNT1 impacts the levels of adenylates. ADNT1-deficient plants exhibited a differential expression pattern of hypoxia-related genes with an increase in non-fermenting-related-kinase 1 (SnRK1) expression and upregulation of adenylate kinase (ADK) under stress and non-stress conditions. Together, these results indicated that the lower expression of ADNT1 is associated with an early "hypoxic status" due to the perturbation of the adenylate pool caused by reduced AMP import by mitochondria. This perturbation, which is sensed by SnRK1, results in a metabolic reprogramming associated with early induction of the fermentative pathway in ADNT1 deficient plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Transporte da Membrana Mitocondrial , Humanos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Hipóxia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo
3.
Food Chem ; 375: 131850, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34953242

RESUMO

Fruit pungency is caused by the accumulation of capsaicinoids, secondary metabolites whose relation to primary metabolism remains unclear. We have selected ten geographically diverse accessions of Capsicum chinense Jacq with different pungency levels. A detailed metabolic profile was conducted in the fruit placenta and pericarp at 20, 45, and 60 days after anthesis aiming at increasing our understanding of the metabolic changes in these tissues across fruit development and their potential connection to capsaicin metabolism. Overall, despite the variation in fruit pungency among the ten accessions, the composition and metabolite levels in both placenta and pericarp were uniformly stable across accessions. Most of the metabolite variability occurred between the fruit developmental stages rather than among the accessions. Interestingly, different metabolite adjustments in the placenta were observed among pungent and non-pungent accessions, which seem to be related to differences in the genetic background. Furthermore, we observed high coordination between metabolites and capsaicin production in C. chinense fruits, suggesting that pungency in placenta is adjusted with primary metabolism.


Assuntos
Capsicum , Piper nigrum , Capsaicina/análise , Frutas/química , Reprodução
4.
Plants (Basel) ; 10(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209492

RESUMO

In plants, vesicular trafficking is crucial for the response and survival to environmental challenges. The active trafficking of vesicles is essential to maintain cell homeostasis during salt stress. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are regulatory proteins of vesicular trafficking. They mediate membrane fusion and guarantee cargo delivery to the correct cellular compartments. SNAREs from the Qbc subfamily are the best-characterized plasma membrane SNAREs, where they control exocytosis during cell division and defense response. The Solanum lycopersicum gene SlSNAP33.2 encodes a Qbc-SNARE protein and is induced under salt stress conditions. SlSNAP33.2 localizes on the plasma membrane of root cells of Arabidopsis thaliana. In order to study its role in endocytosis and salt stress response, we overexpressed the SlSNAP33.2 cDNA in a tomato cultivar. Constitutive overexpression promoted endocytosis along with the accumulation of sodium (Na+) in the vacuoles. It also protected the plant from cell damage by decreasing the accumulation of hydrogen peroxide (H2O2) in the cytoplasm of stressed root cells. Subsequently, the higher level of SlSNAP33.2 conferred tolerance to salt stress in tomato plants. The analysis of physiological and biochemical parameters such as relative water content, the efficiency of the photosystem II, performance index, chlorophyll, and MDA contents showed that tomato plants overexpressing SlSNAP33.2 displayed a better performance under salt stress than wild type plants. These results reveal a role for SlSNAP33.2 in the endocytosis pathway involved in plant response to salt stress. This research shows that SlSNAP33.2 can be an effective tool for the genetic improvement of crop plants.

5.
Sci Rep ; 11(1): 7098, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33782506

RESUMO

Hexokinases (HXKs) and fructokinases (FRKs) are the only two families of enzymes in plants that have been identified as able to phosphorylate Glucose (Glc) and Fructose (Fru). Glc can only be phosphorylated in plants by HXKs, while Fru can be phosphorylated by either HXKs or FRKs. The various subcellular localizations of HXKs in plants indicate that they are involved in diverse functions, including anther dehiscence and pollen germination, stomatal closure in response to sugar levels, stomatal aperture and reducing transpiration. Its association with modulating programmed cell death, and responses to oxidative stress and pathogen infection (abiotic and biotic stresses) also have been reported. To extend our understanding about the function of HXK-like genes in the response of Prunus rootstocks to abiotic stress, we performed a detailed bioinformatic and functional analysis of hexokinase 3-like genes (HXK3s) from two Prunus rootstock genotypes, 'M.2624' (Prunus cerasifera Ehrh × P. munsoniana W.Wight & Hedrick) and 'M.F12/1' (P. avium L.), which are tolerant and sensitive to hypoxia stress, respectively. A previous large-scale transcriptome sequencing of roots of these rootstocks, showed that this HXK3-like gene that was highly induced in the tolerant genotype under hypoxia conditions. In silico analysis of gene promoters from M.2624 and M.F12/1 genotypes revealed regulatory elements that could explain differential transcriptional profiles of HXK3 genes. Subcellular localization was determinates by both bioinformatic prediction and expression of their protein fused to the green fluorescent protein (GFP) in protoplasts and transgenic plants of Arabidopsis. Both approaches showed that they are expressed in plastids. Metabolomics analysis of Arabidopsis plants ectopically expressing Prunus HXK3 genes revealed that content of several metabolites including phosphorylated sugars (G6P), starch and some metabolites associated with the TCA cycle were affected. These transgenic Arabidopsis plants showed improved tolerance to salt and drought stress under growth chamber conditions. Our results suggest that Prunus HXK3 is a potential candidate for enhancing tolerance to salt and drought stresses in stone fruit trees and other plants.


Assuntos
Arabidopsis/fisiologia , Hexoquinase/genética , Prunus/genética , Tolerância ao Sal/genética , Sequência de Aminoácidos , Arabidopsis/genética , Hexoquinase/química , Hipóxia/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos
6.
Plant Cell Physiol ; 62(5): 798-814, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33693904

RESUMO

In Arabidopsis thaliana, two genes encode the E2 subunit of the 2-oxoglutarate dehydrogenase (2-OGDH), a multimeric complex composed of three subunits. To functionally characterize the isoforms of E2 subunit, we isolated Arabidopsis mutant lines for each gene encoding the E2 subunit and performed a detailed molecular and physiological characterization of the plants under controlled growth conditions. The functional lack of expression of E2 subunit isoforms of 2-OGDH increased plant growth, reduced dark respiration and altered carbohydrate metabolism without changes in the photosynthetic rate. Interestingly, plants from e2-ogdh lines also exhibited reduced seed weight without alterations in total seed number. We additionally observed that downregulation of 2-OGDH activity led to minor changes in the levels of tricarboxylic acid cycle intermediates without clear correlation with the reduced expression of specific E2-OGDH isoforms. Furthermore, the e2-ogdh mutant lines exhibited a reduction by up to 25% in the leaf total amino acids without consistent changes in the amino acid profile. Taken together, our results indicate that the two isoforms of E2 subunit play a similar role in carbon-nitrogen metabolism, in plant growth and in seed weight.


Assuntos
Arabidopsis/fisiologia , Carbono/metabolismo , Complexo Cetoglutarato Desidrogenase/metabolismo , Nitrogênio/metabolismo , Arabidopsis/crescimento & desenvolvimento , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Germinação , Complexo Cetoglutarato Desidrogenase/genética , Fotossíntese , Filogenia , Subunidades Proteicas , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/enzimologia , Sementes/crescimento & desenvolvimento
7.
Biochem J ; 477(9): 1759-1777, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32329787

RESUMO

A homolog of the mitochondrial succinate/fumarate carrier from yeast (Sfc1p) has been found in the Arabidopsis genome, named AtSFC1. The AtSFC1 gene was expressed in Escherichia coli, and the gene product was purified and reconstituted in liposomes. Its transport properties and kinetic parameters demonstrated that AtSFC1 transports citrate, isocitrate and aconitate and, to a lesser extent, succinate and fumarate. This carrier catalyzes a fast counter-exchange transport as well as a low uniport of substrates, exhibits a higher transport affinity for tricarboxylates than dicarboxylates, and is inhibited by pyridoxal 5'-phosphate and other inhibitors of mitochondrial carriers to various degrees. Gene expression analysis indicated that the AtSFC1 transcript is mainly present in heterotrophic tissues, and fusion with a green-fluorescent protein localized AtSFC1 to the mitochondria. Furthermore, 35S-AtSFC1 antisense lines were generated and characterized at metabolic and physiological levels in different organs and at various developmental stages. Lower expression of AtSFC1 reduced seed germination and impaired radicle growth, a phenotype that was related to reduced respiration rate. These findings demonstrate that AtSFC1 might be involved in storage oil mobilization at the early stages of seedling growth and in nitrogen assimilation in root tissue by catalyzing citrate/isocitrate or citrate/succinate exchanges.


Assuntos
Arabidopsis , Proteínas de Transporte , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Transporte Biológico , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Transportadores de Ácidos Dicarboxílicos/genética , Transportadores de Ácidos Dicarboxílicos/metabolismo , Ácidos Graxos/metabolismo , Fumaratos/metabolismo , Expressão Gênica , Genes Fúngicos , Genes de Plantas , Cinética , Lipossomos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Nitrogênio/metabolismo , Saccharomyces cerevisiae/genética , Plântula/crescimento & desenvolvimento , Succinatos/metabolismo , Ácidos Tricarboxílicos/metabolismo
8.
Data Brief ; 27: 104545, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31673575

RESUMO

Maqui (Aristotelia chilensis [Molina] Stunz) is a small dioecious tree, belonging to the Elaeocarpaceae family. Maqui fruit has high levels of antioxidant activity, which are due to elevated anthocyanin and polyphenol content. Here we describe a draft genome sequence data of maqui (A. chilensis). The genomic sequence datasets were obtained using Illumina NextSeq platform. Nucleotide sequences of raw reads and the assembled draft genome are available at NCBI's Sequence Read Archive as BioProject PRJNA544858. Also, a total of 210067 microsatellite or simple sequence repeat (SSR) markers were identified.

9.
Data Brief ; 25: 104258, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31485465

RESUMO

In this work, we partially sequenced genomes of two Atriplex species (A. deserticola Phil. and A. atacamensis Phil.), using Illumina technology (Hiseq 2500 paired-end system) and de novo assembly strategy. Raw data of A. deserticola and A. atacamensis are available from NCBI-Bioproject, PRJNA495747 and PRJNA495763 accessions, respectively. A total of 127086 and 134984 microsatellite or simple sequence repeat (SSR) markers were identified within A. deserticola and A. atacamensis genomic DNA, respectively. In addition, predicted putative genes in A. deserticola and A. atacamensis sequences are also presented in this article.

10.
Plant Mol Biol ; 101(1-2): 183-202, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286324

RESUMO

KEY MESSAGE: Isoforms of 2-OGDH E1 subunit are not functionally redundant in plant growth and development of A. thaliana. The tricarboxylic acid cycle enzyme 2-oxoglutarate dehydrogenase (2-OGDH) converts 2-oxoglutarate (2-OG) to succinyl-CoA concomitant with the reduction of NAD+. 2-OGDH has an essential role in plant metabolism, being both a limiting step during mitochondrial respiration as well as a key player in carbon-nitrogen interactions. In Arabidopsis thaliana two genes encode for E1 subunit of 2-OGDH but the physiological roles of each isoform remain unknown. Thus, in the present study we isolated Arabidopsis T-DNA insertion knockout mutant lines for each of the genes encoding the E1 subunit of 2-OGDH enzyme. All mutant plants exhibited substantial reduction in both respiration and CO2 assimilation rates. Furthermore, mutant lines exhibited reduced levels of chlorophylls and nitrate, increased levels of sucrose, malate and fumarate and minor changes in total protein and starch levels in leaves. Despite the similar metabolic phenotypes for the two E1 isoforms the reduction in the expression of each gene culminated in different responses in terms of plant growth and seed production indicating distinct roles for each isoform. Collectively, our results demonstrated the importance of the E1 subunit of 2-OGDH in both autotrophic and heterotrophic tissues and suggest that the two E1 isoforms are not functionally redundant in terms of plant growth in A. thaliana.


Assuntos
Arabidopsis/enzimologia , Carbono/metabolismo , Complexo Cetoglutarato Desidrogenase/metabolismo , Nitrogênio/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Complexo Cetoglutarato Desidrogenase/genética , Mitocôndrias/enzimologia , Mutagênese Insercional , Nitratos/metabolismo , Fenótipo , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Isoformas de Proteínas , Subunidades Proteicas , Plântula/enzimologia , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/enzimologia , Sementes/genética , Sementes/crescimento & desenvolvimento
11.
J Plant Physiol ; 238: 29-39, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129469

RESUMO

Control of gene expression and induction of cellular protection mechanisms are two important processes that plants employ to protect themselves against abiotic stresses. ABA-, stress, and ripening-induced (ASR) proteins have been identified to participate in such responses. Previous studies have proposed that these proteins can act as transcription factors and as molecular chaperones protecting transgenic plants against stresses; however a gene network regulated by ASRs has not been explored. To expand our knowledge on the function of these proteins in cereals, we present the functional characterization of a barley ASR gene. Expression of HvASR5 was almost ubiquitous in different organs and responded to ABA and to different stress treatments. When expressed ectopically, HvASR5 was able to confer drought and salt stress tolerance to Arabidopsis thaliana and to improve growth performance of rice plants under stress conditions. A transcriptomic analysis with two transgenic rice lines overexpressing HvASR5 helped to identify potential downstream targets and understand ASR-regulated cellular processes. HvASR5 up-regulated the expression of a distinct set of genes associated with stress responses, metabolic processes (particularly carbohydrate metabolism), as well as reproduction and development. These data, together with the confirmed nuclear and cytoplasmic localization of HvASR5, further support the hypothesis that HvASR5 can also carry out roles as molecular protector and transcriptional regulator.


Assuntos
Genes de Plantas/genética , Hordeum/genética , Oryza/genética , Proteínas de Plantas/fisiologia , Clonagem Molecular , Perfilação da Expressão Gênica , Genes de Plantas/fisiologia , Hordeum/metabolismo , Hordeum/fisiologia , Oryza/metabolismo , Oryza/fisiologia , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Análise de Sequência de DNA , Estresse Fisiológico
12.
Plant Mol Biol ; 90(1-2): 63-76, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26497001

RESUMO

In grapevine, anthocyanins and proanthocyanidins are the main flavonoids in berries, which are associated to organoleptic properties in red wine such as color and astringency. Flavonoid pathway is specifically regulated at transcriptional level and several R2R3-MYB proteins have shown to act as positive regulators. However, some members of this family have shown to repress the flavonoid biosynthesis. In this work, we present the characterization of VvMYB4-like gene, which encodes a putative transcriptional factor highly expressed in the skin of berries at the pre veraison stage in grapevine. Its over-expression in tobacco resulted in the loss of pigmentation in flowers due a decrease in anthocyanin accumulation. Severity in anthocyanin suppression observed in petals could be associated with the expression level of the VvMYB4-like transgene. Expression analysis of flavonoid structural genes revealed the strong down-regulation of the flavonoid-related genes anthocyanidin synthase (ANS) and dihydroflavonol reductase (DFR) genes and also the reduction of the anthocyanin-related gene UDP glucose:flavonoid 3-O-glucosyl transferase (UFGT), which was dependent of the transgene expression. In addition, expression of VvMYB4-like in the model plant Arabidopsis showed similar results, with the higher down-regulation observed in the AtDFR and AtLDOX genes. These results suggest that VvMYB4-like may play an important role in regulation of anthocyanin biosynthesis in grapevine acting as a transcriptional repressor of flavonoid structural genes.


Assuntos
Antocianinas/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/genética , Vitis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação para Baixo , Flavonoides/metabolismo , Flores/genética , Flores/metabolismo , Frutas/genética , Frutas/metabolismo , Filogenia , Pigmentação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/genética , Nicotiana/metabolismo , Fatores de Transcrição/metabolismo
13.
Plant Cell Rep ; 33(7): 1147-59, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24700246

RESUMO

KEY MESSAGE: VvMATE1 and VvMATE2 encode putative PA transporters expressed during seed development in grapevine. The subcellular localization of these MATE proteins suggests different routes for the intracellular transport of PAs. Proanthocyanidins (PAs), also called condensed tannins, protect plants against herbivores and are important quality components of many fruits. PAs biosynthesis is part of the flavonoid pathway that also produces anthocyanins and flavonols. In grape fruits, PAs are present in seeds and skin tissues. PAs are synthesized in the cytoplasm and accumulated into the vacuole and apoplast; however, little is known about the mechanisms involved in the transport of these compounds to such cellular compartments. A gene encoding a Multidrug And Toxic compound Extrusion (MATE) family protein suggested to transport anthocyanins-named VvMATE1-was used to identify a second gene of the MATE family, VvMATE2. Analysis of their deduced amino acid sequences and the phylogenetic relationship with other MATE-like proteins indicated that VvMATE1 and VvMATE2 encode putative PA transporters. Subcellular localization assays in Arabidopsis protoplasts transformed with VvMATE-GFP fusion constructs along with organelle-specific markers revealed that VvMATE1 is localized in the tonoplast whereas VvMATE2 is localized in the Golgi complex. Major expression of both genes occurs during the early stages of seed development concomitant with the accumulation of PAs. Both genes are poorly expressed in the skin of berries while VvMATE2 is also expressed in leaves. The presence of putative cis-acting elements in the promoters of VvMATE1 and VvMATE2 may explain the differential transcriptional regulation of these genes in grapevine. Altogether, these results suggest that these MATE proteins could mediate the transport and accumulation of PAs in grapevine through different routes and cellular compartments.


Assuntos
Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proantocianidinas/metabolismo , Vitis/genética , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Frutas/genética , Regulação da Expressão Gênica de Plantas , Complexo de Golgi/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos , Vitis/crescimento & desenvolvimento
14.
Plant Cell Rep ; 33(1): 61-73, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24085307

RESUMO

KEY MESSAGE: Rice ASR genes respond distinctly to abscisic acid, dehydration and cold stress. Their tissue-specific expression provides new hints about their possible roles in plant responses to stress. Plant ASR proteins have emerged as an interesting distinct group of proteins with apparent roles in protecting cellular structures as well as putative regulators of gene expression, both important responses of plants to environmental stresses. Regardless of the possible functions proposed by different studies, little is known about their role in cereals. To further understand the function of these proteins in the Gramineae, we investigated the expression pattern of the six ASR genes present in the rice genome in response to ABA, stress conditions and in different organs. Although transcription of most OsASRs is transiently enhanced by ABA treatment, the genes present a differential response under cold and drought stress as well as specific expression in certain tissues and organs. Analysis of their promoters reveals regulatory cis-elements associated to hormonal, sugar and stress responses. The promoters of two genes, OsASR1 and OsASR5, direct the expression of the GUS reporter gene especially to leaf vascular tissue in response to dehydration and low temperature. In control conditions, a GUS reporter assay also indicates specific expression of these two genes in roots, anthers and seed scutellar tissues. These results provide new clues about the possible role of ASRs in plant stress responses and development.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Especificidade de Órgãos/genética , Oryza/genética , Oryza/fisiologia , Estresse Fisiológico/genética , Ácido Abscísico/farmacologia , Temperatura Baixa , Secas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucuronidase/metabolismo , Especificidade de Órgãos/efeitos dos fármacos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Estresse Fisiológico/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos
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