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1.
BMC Plant Biol ; 19(1): 368, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429706

RESUMO

BACKGROUND: We previously reported the involvement of nitric oxide (NO) and cyclic nucleotide-gated ion channel 6 (CNGC6) in the responses of plants to heat shock (HS) exposure. To elucidate their relationship with heat tolerance in Arabidopsis thaliana, we examined the effects of HS on several groups of seedlings: wild type, cngc6, and cngc6 complementation and overexpression lines. RESULTS: After HS exposure, the level of NO was lower in cngc6 seedlings than in wild-type seedlings but significantly elevated in the transgenic lines depending on CNGC6 expression level. The treatment of seeds with calcium ions (Ca2+) enhanced the NO level in Arabidopsis seedlings under HS conditions, whereas treatment with EGTA (a Ca2+ chelator) reduced it, implicating that CNGC6 stimulates the accumulation of NO depending on an increase in cytosolic Ca2+ ([Ca2+]cyt). This idea was proved by phenotypic observations and thermotolerance testing of transgenic plants overexpressing NIA2 and NOA1, respectively, in a cngc6 background. Western blotting indicated that CNGC6 stimulated the accumulation of HS proteins via NO. CONCLUSION: These data indicate that CNGC6 acts upstream of NO in the HS pathway, which improves our insufficient knowledge of the initiation of plant responses to high temerature.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cálcio/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Óxido Nítrico/metabolismo , Termotolerância , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Canais de Cálcio/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Citosol/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico , Mutação , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Plântula/genética , Plântula/metabolismo
2.
J Agric Food Chem ; 67(35): 9772-9781, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31398019

RESUMO

This study aims to investigate the response profiles of vitamin E and carotenoids on transcription and metabolic levels of sweet corn seedlings under temperature stress. The treated temperatures were set as 10 °C (low temperature, LT), 25 °C (control, CK), and 40 °C (high temperature, HT) for sweet corn seedlings. The gene expression profiles of vitamin E and carotenoids biosynthesis pathways were analyzed by real time quantitative polymerase chain reaction (RT-qPCR), and the composition profiles were analyzed by high performance liquid chromatography (HPLC). Results showed that vitamin E gradually accumulated in response to LT stress but was limited by HT stress. The increase of carotenoids was suppressed by LT stress whereas HT stress promoted it. The existing results elaborated the interactive and competitive relationships of vitamin E and carotenoids in sweet corn seedlings to respond to extreme temperature stress at transcriptional and metabolic levels. The present study would improve sweet corn temperature resilience with integrative knowledge in the future.


Assuntos
Carotenoides/metabolismo , Vitamina E/metabolismo , Zea mays/metabolismo , Carotenoides/análise , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plântula/química , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Estresse Fisiológico , Temperatura Ambiente , Vitamina E/análise , Zea mays/química , Zea mays/genética , Zea mays/crescimento & desenvolvimento
3.
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
4.
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
5.
Plant Mol Biol ; 101(1-2): 203-220, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31297725

RESUMO

KEY MESSAGE: Here, a functional characterization of a wheat MSR has been presented: this protein makes a contribution to the plant's tolerance of abiotic stress, acting through its catalytic capacity and its modulation of ROS and ABA pathways. The molecular mechanism and function of certain members of the methionine sulfoxide reductase (MSR) gene family have been defined, however, these analyses have not included the wheat equivalents. The wheat MSR gene TaMSRA4.1 is inducible by salinity and drought stress and in this study, we demonstrate that its activity is restricted to the Met-S-SO enantiomer, and its subcellular localization is in the chloroplast. Furthermore, constitutive expression of TaMSRA4.1 enhanced the salinity and drought tolerance of wheat and Arabidopsis thaliana. In these plants constitutively expressing TaMSRA4.1, the accumulation of reactive oxygen species (ROS) was found to be influenced through the modulation of genes encoding proteins involved in ROS signaling, generation and scavenging, while the level of endogenous abscisic acid (ABA), and the sensitivity of stomatal guard cells to exogenous ABA, was increased. A yeast two-hybrid screen, bimolecular fluorescence complementation and co-immunoprecipitation assays demonstrated that heme oxygenase 1 (HO1) interacted with TaMSRA4.1, and that this interaction depended on a TaHO1 C-terminal domain. In plants subjected to salinity or drought stress, TaMSRA4.1 reversed the oxidation of TaHO1, activating ROS and ABA signaling pathways, but not in the absence of HO1. The aforementioned properties advocate TaMSRA4.1 as a candidate for plant genetic enhancement.


Assuntos
Heme Oxigenase-1/metabolismo , Metionina Sulfóxido Redutases/metabolismo , Transdução de Sinais , Estresse Fisiológico , Triticum/enzimologia , Ácido Abscísico/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/fisiologia , Secas , Perfilação da Expressão Gênica , Heme Oxigenase-1/genética , Metionina Sulfóxido Redutases/genética , Oxirredução , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Salinidade , Tolerância ao Sal , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Triticum/genética , Triticum/fisiologia , Técnicas do Sistema de Duplo-Híbrido
6.
Physiol Plant ; 166(4): 892-893, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31294874

RESUMO

Drought is an increasingly common climatic event that can devastate ecosystems, as well as surrounding agricultural and forestry industries. Few places face this challenge more than Australia, where millennia of droughts linked to geography and climatic drivers, such as El Niño, have shaped the flora and fauna into forms predicated on resilience and economy. How an organism responds to these cyclic challenges is a combination of the inherent tolerance mechanisms encoded in their genome and outside influences, such as the effect of nutrients and symbiotic interactions. In this issue of Physiologia Plantarum, Tariq et al. (2019) describes how the presence of the element phosphorus can bolster the physiological and biochemical response of eucalypt seedlings to severe drought conditions.


Assuntos
Secas , Genoma de Planta/genética , Fósforo/metabolismo , Plântula/genética , Plântula/metabolismo , Austrália
7.
BMC Plant Biol ; 19(1): 300, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288738

RESUMO

BACKGROUND: Salinity is a major abiotic stress that limits the growth, productivity, and geographical distribution of plants. A comparative proteomics and gene expression analysis was performed to better understand salinity tolerance mechanisms in chickpea. RESULTS: Ten days of NaCl treatments resulted in the differential expression of 364 reproducible spots in seedlings of two contrasting chickpea genotypes, Flip 97-43c (salt tolerant, T1) and Flip 97-196c (salt susceptible, S1). Notably, after 3 days of salinity, 80% of the identified proteins in T1 were upregulated, while only 41% in S2 had higher expression than the controls. The proteins were classified into eight functional categories, and three groups of co-expression profile. The second co-expressed group of proteins had higher and/or stable expression in T1, relative to S2, suggesting coordinated regulation and the importance of some processes involved in salinity acclimation. This group was mainly enriched in proteins associated with photosynthesis (39%; viz. chlorophyll a-b binding protein, oxygen-evolving enhancer protein, ATP synthase, RuBisCO subunits, carbonic anhydrase, and fructose-bisphosphate aldolase), stress responsiveness (21%; viz. heat shock 70 kDa protein, 20 kDa chaperonin, LEA-2 and ascorbate peroxidase), and protein synthesis and degradation (14%; viz. zinc metalloprotease FTSH 2 and elongation factor Tu). Thus, the levels and/or early and late responses in the activation of targeted proteins explained the variation in salinity tolerance between genotypes. Furthermore, T1 recorded more correlations between the targeted transcripts and their corresponding protein expression profiles than S2. CONCLUSIONS: This study provides insight into the proteomic basis of a salt-tolerance mechanism in chickpea, and offers unexpected and poorly understood molecular resources as reliable starting points for further dissection.


Assuntos
Cicer/fisiologia , Proteínas de Plantas/metabolismo , Proteômica , Cicer/genética , Regulação da Expressão Gênica de Plantas , Genótipo , Fotossíntese , Proteínas de Plantas/genética , Salinidade , Tolerância ao Sal , Plântula/genética , Plântula/fisiologia , Estresse Fisiológico
8.
Plant Cell Rep ; 38(9): 1165-1180, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31161264

RESUMO

KEY MESSAGE: Arabidopsis photorespiratory gene AtAGT1 is important for the growth and development of root, the non-photosynthetic organ, and it is involved in a complex metabolic network and salt resistance. AtAGT1 in Arabidopsis encodes an aminotransferase that has a wide range of donor:acceptor combinations, including Asn:glyoxylate. Although it is one of the photorespiratory genes, its encoding protein has been suggested to function also in roots to metabolize Asn. However, experimental data are still lacking. In this study, we investigated experimentally the function of AtAGT1 in roots and our results uncovered its importance in root development during seedling establishment after seed germination. Overexpression of AtAGT1 in roots promoted both the growth of primary root and outgrowth of lateral roots. To further elucidate the molecular mechanisms underlying, amino acid content and gene expression in roots were analyzed, and results revealed that AtAGT1 is involved in a complex metabolic network and salt resistance of roots.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Reguladores de Crescimento de Planta/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Expressão Gênica , Germinação , Plantas Geneticamente Modificadas , Tolerância ao Sal , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Transaminases/genética , Transaminases/metabolismo
9.
Planta ; 250(2): 657-665, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31147828

RESUMO

MAIN CONCLUSION: The grapevine VvßVPE promoter is specifically expressed in the seed. The - 1306~- 1045 bp core region restricts expression in other tissues and organs. Vacuolar processing enzyme (VPE) is a cysteine proteinase regulating vacuolar protein maturation and executing programmed cell death (PCD) in plants. Vitis vinifera (Vv)ßVPE is a ß-type VPE showing seed-specific expression that processes seed proteins during ovule development. However, the regulation of the seed-specific gene expression is far from understood. In this study, we characterize VvßVPE promoter (pVvßVPE) from 12 seeded and seedless grape genotypes. 94.56% of the pVvßVPE coding sequence is consistent. Two ßVPE promoters were constructed and transformed into Arabidopsis thaliana via ß-glucuronidase (GUS) fused expression vectors, using cv. Pinot Noir and cv. Thompson as seed and seedless candidates. GUS staining in different tissues and organs revealed that VvßVPE expresses specifically in the embryo, including the cotyledon, hypocotyl and suspensor, but not in the leaf, stem, root or flowers of the seedling. Using promoter deletion analysis, we created four incomplete VvßVPE promoters and found each pVvßVPE deletion could drive GUS gene to express in seeds. Interestingly, seed specificity disappeared when the promoter missed the core - 1306~- 1045 bp region. All deletion promoters presenting various quantified GUS activities indicate that the region - 1704~- 1306 bp inhibits, and the region - 705~- 861 bp promotes gene expression of VvßVPE. Our results demonstrate that pVvßVPE is a seed-specific promoter in both seeded and seedless grapes. Moreover, the core region of pVvßVPE (- 1306~- 1045 bp) is the key one responsible for seed-specific expression.


Assuntos
Cisteína Endopeptidases/genética , Regiões Promotoras Genéticas/genética , Sementes/genética , Vitis/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes Reporter , Especificidade de Órgãos , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento
10.
Plant Physiol Biochem ; 141: 415-422, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31229926

RESUMO

This study aimed to investigate the possible alleviating effect of chitosan on salt-induced growth retardation and oxidative stress and to elucidate whether this effect is linked to activation of mitochondrial respiration on the basis of alternative respiration in maize seedlings. Salt stress significantly reduced root length and plant height in comparison to the control, whereas foliar application of chitosan ameliorated the adverse effect of salinity to a certain degree. Moreover, chitosan resulted in plant growth promotion as compared to unstressed seedlings. The separate applications of chitosan and salt had a stimulatory effect on the activities of antioxidant enzymes; however, combined application of chitosan and salt were more effective than that of chitosan or salt alone. Similarly, mitochondrial total respiration rate (Vt) and alternative respiration capacity (Valt) were increased by separate applications of chitosan and salt; however, the combination of chitosan and salt gave the highest values for these parameters. The highest values of Valt/Vt was recorded at seedlings treated with salt plus chitosan. Similarly, cytochrome respiration capacity was also increased by chitosan in both stress-free and stressed conditions. In addition, AOX1, encoding alternative oxidase, was significantly upregulated by chitosan and/or salt. The maximum transcript level was recorded at seedlings treated with salt plus chitosan. Chitosan also significantly decreased superoxide anion and hydrogen peroxide contents and lipid peroxidation level under normal and the stressed conditions. These results suggest that the mitigating effect of chitosan on salt stress is linked to activation of alternative respiration at biochemical and molecular level.


Assuntos
Quitosana/química , Regulação da Expressão Gênica de Plantas , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Tolerância ao Sal , Plântula/genética , Zea mays/genética , Antioxidantes/metabolismo , Citocromos/metabolismo , Perfilação da Expressão Gênica , Peroxidação de Lipídeos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Estresse Oxidativo , Oxirredutases/genética , Proteínas de Plantas/genética , RNA/metabolismo , Estresse Fisiológico , Zea mays/enzimologia
11.
Plant Mol Biol ; 101(1-2): 1-19, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062216

RESUMO

KEY MESSAGE: The circadian clock controls many molecular activities, impacting experimental interpretation. We quantify the genome-wide effects of time-of-day on the heat-shock response and the effects of "diurnal bias" in stress experiments. Heat stress has significant adverse effects on plant productivity worldwide. Most experiments examining heat stress are performed during daytime hours, generating a 'diurnal bias' in the pathways and regulatory mechanisms identified. Such bias may confound downstream interpretations and limit our understanding of the full response to heat stress. Here we show that the transcriptional and physiological responses to a sudden heat shock in Arabidopsis are profoundly sensitive to the time of day. We observe that plant tolerance and acclimation to heat shock vary throughout the day and are maximal at dusk. Consistently, over 75% of heat-responsive transcripts show a time of day-dependent response, including many previously characterized heat-response genes. This temporal sensitivity implies a complex interaction between time and temperature where daily variations in basal transcription influence thermotolerance. When we examined these transcriptional responses, we uncovered novel night-response genes and cis-regulatory elements, underpinning new aspects of heat stress responses not previously appreciated. Exploiting this temporal variation can be applied to most environmental responses to understand the underlying network wiring. Therefore, we propose that using time as a perturbagen is an approach that will enhance our understanding of plant regulatory networks and responses to environmental stresses.


Assuntos
Arabidopsis/fisiologia , Relógios Circadianos/genética , Redes Reguladoras de Genes , Genoma de Planta/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Aclimatação , Arabidopsis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Temperatura Alta , Plântula/genética , Plântula/fisiologia , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
BMC Res Notes ; 12(1): 243, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036050

RESUMO

OBJECTIVE: Conifer genomes show high genetic diversity in intergenic regions that contain diverse sets of transposable elements with dominating long terminal repeat (LTR) retrotransposons (RE). Transcription of RE in response to environmental stimuli could produce various types of regulatory non-coding RNAs, but global genomic methylation changes could result in a coincidental expression of normally silent genomic regions. Expression of several RE families was evaluated in Scots pine seedlings after controlled inoculations with two fungal species that exhibit different modes of pathogenicity (necrotrophic and likely biotrophic); data compared to the overall RE distribution in genome. Recognition of regulatory non-coding RNA involved in host-pathogen interplay could be valuable in understanding defence mechanisms of perennial plants. RESULTS: In the case of necrotrophic fungi Heterobasidion annosum (HA), short activation followed by restriction of RE expression was revealed after inoculation and during the spread of the pathogen. After inoculation with Lophodermium seditiosum (LS), an early increase in RE expression was revealed with the spread of the pathogen and subsequent transcription rise in all seedlings. Our observations indicate that in the complex plant genome multiple RE families constitutively express in response to pathogen invasion and these sequences could undergo regulation related to host response or pathogen influence.


Assuntos
Regulação da Expressão Gênica de Plantas/imunologia , Genoma de Planta , Pinus sylvestris/genética , Doenças das Plantas/genética , Retroelementos/imunologia , Plântula/genética , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/patogenicidade , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Pinus sylvestris/imunologia , Pinus sylvestris/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Raízes de Plantas/genética , Raízes de Plantas/imunologia , Raízes de Plantas/microbiologia , Brotos de Planta/genética , Brotos de Planta/imunologia , Brotos de Planta/microbiologia , Plântula/imunologia , Plântula/microbiologia , Sequências Repetidas Terminais , Transcrição Genética
13.
Plant Cell Physiol ; 60(8): 1790-1803, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111914

RESUMO

The elucidation of epigenetic responses of salt-responsive genes facilitates understanding of the underlying mechanisms that confer salt tolerance in rice. However, it is still largely unknown how epigenetic mechanisms are associated with the expression of salt-responsive genes in rice and other crops. In this study, we reported tissue-specific gene expression and tissue-specific changes in chromatin modifications or signatures between seedlings and roots in response to salt treatment. Our study indicated that among six of individual mark examined (H3K4me3, H3K27me3, H4K12ac, H3K9ac, H3K27ac and H3K36me3), a positive association between salt-related changes in histone marks and the expression of differentially expressed genes (DEGs) was observed only for H3K9ac and H4K12ac in seedlings and H3K36me3 in roots. In contrast, chromatin states (CSs) with combinations of six histone modification marks played crucial roles in the differential expression of salt-responsive genes between seedlings and roots. Most importantly, CS7 containing the bivalent marks H3K4me3 and H3K27me3, with a mutual exclusion of functions with each other, displayed distinct functions in the expression of DEGs in both tissues. Specifically, H3K27me3 in CS7 mainly suppressed the expression of DEGs in roots, while H3K4me3 affected the expression of down- and up-regulated genes, possibly by antagonizing the repressive role of H3K27me3 in seedlings. Our findings indicate distinct impacts of the CSs on the differential expression of salt-responsive genes between seedlings and roots in rice, which provides an important background for understanding chromatin-based epigenetic mechanisms that might confer salt tolerance in plants.


Assuntos
Cromatina/metabolismo , Oryza/metabolismo , Raízes de Plantas/metabolismo , Plântula/metabolismo , Divisão Celular/genética , Divisão Celular/fisiologia , Regulação da Expressão Gênica de Plantas , Oryza/genética , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Fotossíntese/genética , Fotossíntese/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Plântula/genética
14.
Int J Mol Sci ; 20(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31071918

RESUMO

BACKGROUND: Peanut (Arachis hypogaea L.), an important oilseed and food legume, is widely cultivated in the semi-arid tropics. Drought is the major stress in this region which limits productivity. Microbial communities in the rhizosphere are of special importance to stress tolerance. However, relatively little is known about the relationship between drought and microbial communities in peanuts. METHOD: In this study, deep sequencing of the V3-V4 region of the 16S rRNA gene was performed to characterize the microbial community structure of drought-treated and untreated peanuts. RESULTS: Taxonomic analysis showed that Actinobacteria, Proteobacteria, Saccharibacteria, Chloroflexi, Acidobacteria and Cyanobacteria were the dominant phyla in the peanut rhizosphere. Comparisons of microbial community structure of peanuts revealed that the relative abundance of Actinobacteria and Acidobacteria dramatically increased in the seedling and podding stages in drought-treated soil, while that of Cyanobacteria and Gemmatimonadetes increased in the flowering stage in drought-treated rhizospheres. Metagenomic profiling indicated that sequences related to metabolism, signaling transduction, defense mechanism and basic vital activity were enriched in the drought-treated rhizosphere, which may have implications for plant survival and drought tolerance. CONCLUSION: This microbial communities study will form the foundation for future improvement of drought tolerance of peanuts via modification of the soil microbes.


Assuntos
Arachis/microbiologia , Secas , Microbiota/genética , Estresse Fisiológico/genética , Acidobacteria/classificação , Acidobacteria/genética , Actinobacteria/classificação , Actinobacteria/genética , Arachis/genética , Chloroflexi/classificação , Chloroflexi/genética , Cianobactérias/classificação , Cianobactérias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Raízes de Plantas/microbiologia , Proteobactérias/classificação , Proteobactérias/genética , RNA Ribossômico 16S/genética , Rizosfera , Plântula/genética , Microbiologia do Solo , Clima Tropical
15.
Environ Sci Pollut Res Int ; 26(20): 20208-20218, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31098903

RESUMO

Cyanate (CNO-) has been produced in the environment through either natural or anthropogenic sources. However, due to industrialization, it has been led more over-loads. In this study, interaction of CNO- uptake by rice seedlings with nitrate assimilation was investigated using gene expression analysis after an acute phytotoxicity assay. Our results showed that CNO- exposure caused inhibition on relative growth rates of plants. CNO- analysis demonstrated that rice seedlings had higher potential for CNO- uptake and the removal rates showed a zero-order kinetic. PCR analysis exposed that OsCYN transcript was not significantly induced by CNO- treatments in rice tissues and CNO- exposure also repressed gene expression of the collaborative enzyme carbonic anhydrase (CA), suggesting that assimilation of CNO- initiated by the enzyme cyanase (CYN) in rice seedlings was an enzyme-limitation reaction. Gene expression of other enzymes involved in nitrate metabolism was tissue-specific under CNO- exposure, suggesting that rice seedlings were able to trigger its intrinsic regulative and responsive mechanisms to cope up with uneven N conditions. Significant upregulation of three OsGDH isogenes, except for OsGDH1 in roots, was detected in both rice materials with enhancing CNO- concentrations, suggesting that GDH may play a primary role to maintain the balance of C and N in plants under CNO- exposure. In conclusion, because the innate pool of CYN activity was non-sufficient to degrade exogenous CNO- by rice seedlings, CNO-derived ammonium only can serve as a supporting N source to support growth of rice seedling under non-effective doses of CNO- exposure.


Assuntos
Carbono-Nitrogênio Liases/genética , Cianatos/metabolismo , Expressão Gênica/efeitos dos fármacos , Nitratos/metabolismo , Oryza/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Transporte Biológico , Cianatos/farmacologia , Oryza/enzimologia , Oryza/genética , Plântula/enzimologia , Plântula/genética
16.
Environ Sci Pollut Res Int ; 26(20): 21013-21021, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31119539

RESUMO

In this study the phytotoxic, cytotoxic, genotoxic and mutagenic effects of two commercial fungicide-active compounds, procymidone (PR) and iprodione (IP), were determined. The parameters evaluated were germination and root growth, mitotic index, chromosomal and nuclear aberrations, and molecular analyses were also performed in the model plant Allium cepa L. The results demonstrated that the active compounds PR and IP were phytotoxic, delaying germination and slowing the development of A. cepa seedlings. Moreover, PR and IP showed cytogenotoxicity towards A. cepa meristematic cells, inducing chromosomal changes and cell death. The mutagenic activity of the active compounds was demonstrated by the detection of DNA changes in simple sequence repeat (SSR) and inter-simple sequence repeat (ISSR) markers in the treated cells compared to the negative control. Together, these results contribute to a better understanding of the damage caused by these substances in living organisms and reveal a promising strategy for prospective studies of the toxic effects of environmental pollutants.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Compostos Bicíclicos com Pontes/toxicidade , Fungicidas Industriais/toxicidade , Hidantoínas/toxicidade , Mutagênicos/toxicidade , Cebolas/efeitos dos fármacos , Aminoimidazol Carboxamida/toxicidade , Dano ao DNA/efeitos dos fármacos , Germinação/efeitos dos fármacos , Meristema/efeitos dos fármacos , Meristema/genética , Meristema/crescimento & desenvolvimento , Cebolas/genética , Cebolas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento
17.
BMC Plant Biol ; 19(1): 216, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31122195

RESUMO

BACKGROUND: Adaptation to drought-prone environments requires robust root architecture. Genotypes with a more vigorous root system have the potential to better adapt to soils with limited moisture content. However, root architecture is complex at both, phenotypic and genetic level. Customized mapping panels in combination with efficient screenings methods can resolve the underlying genetic factors of root traits. RESULTS: A mapping panel of 233 spring barley genotypes was evaluated for root and shoot architecture traits under non-stress and osmotic stress. A genome-wide association study elucidated 65 involved genomic regions. Among them were 34 root-specific loci, eleven hotspots with associations to up to eight traits and twelve stress-specific loci. A list of candidate genes was established based on educated guess. Selected genes were tested for associated polymorphisms. By this, 14 genes were identified as promising candidates, ten remained suggestive and 15 were rejected. The data support the important role of flowering time genes, including HvPpd-H1, HvCry2, HvCO4 and HvPRR73. Moreover, seven root-related genes, HERK2, HvARF04, HvEXPB1, PIN5, PIN7, PME5 and WOX5 are confirmed as promising candidates. For the QTL with the highest allelic effect for root thickness and plant biomass a homologue of the Arabidopsis Trx-m3 was revealed as the most promising candidate. CONCLUSIONS: This study provides a catalogue of hotspots for seedling growth, root and stress-specific genomic regions along with candidate genes for future potential incorporation in breeding attempts for enhanced yield potential, particularly in drought-prone environments. Root architecture is under polygenic control. The co-localization of well-known major genes for barley development and flowering time with QTL hotspots highlights their importance for seedling growth. Association analysis revealed the involvement of HvPpd-H1 in the development of the root system. The co-localization of root QTL with HERK2, HvARF04, HvEXPB1, PIN5, PIN7, PME5 and WOX5 represents a starting point to explore the roles of these genes in barley. Accordingly, the genes HvHOX2, HsfA2b, HvHAK2, and Dhn9, known to be involved in abiotic stress response, were located within stress-specific QTL regions and await future validation.


Assuntos
Secas , Genes de Plantas/fisiologia , Genoma de Planta/genética , Hordeum/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Genótipo , Hordeum/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento
18.
Cell Mol Biol (Noisy-le-grand) ; 65(3): 18-24, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30942152

RESUMO

Salinity is one of the most important abiotic stress factors that is expanding its influence because of global climate change and global warming. It causes gene expression changes, a reduction in seed germination and related characteristics, and poor seedling establishment in many crop plants by creating a lower osmotic potential in the seedbed and/or toxic ion effects in germinated seeds. In recent years, seed priming has been considered a promising strategy in modern stress management to protect plants against stress conditions. This study was conducted to elucidate the effects of osmopriming with polyethylene glycol 6000 (PEG-6000) on seed germination, seedling growth and gene expression in the common vetch (Vicia sativa L.) in different saline conditions. Common vetch seeds were primed with PEG-6000 solutions having different osmotic potentials (0.00, -0.50,  -0.75, -1.00, -1.25, and -1.50 MPa) for 12 hours. Control (un-primed) and primed seeds were germinated and seedlings were grown in different saline conditions (EC= zero, 4, 8 and 16 dS m-1). Furthermore, gene expression was compared in the primed seedlings in two different osmotic potentials (0.00 and -1.50 MPa) by microarray technology. Results demonstrated that germination percentage of common vetch seeds and seedling growth were diminished by high salinity. However, several priming treatments alleviated the adverse effects of high salinity on germination and early seedling growth of common vetch. The microarray showed that the expression of many genes in both stress and normal conditions was not significantly different.


Assuntos
Regulação da Expressão Gênica de Plantas , Germinação , Salinidade , Estresse Salino , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Vicia sativa/genética , Vicia sativa/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Germinação/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Polietilenoglicóis/farmacologia , Estresse Salino/efeitos dos fármacos , Estresse Salino/genética , Plântula/efeitos dos fármacos , Plântula/genética , Sementes/efeitos dos fármacos , Sementes/genética , Vicia sativa/efeitos dos fármacos
19.
Plant Mol Biol ; 100(1-2): 19-32, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31001712

RESUMO

KEY MESSAGE: BcMAF2 plays a key role in flowering regulation by controlling BcTEM1, BcSOC1 and BCSPL15 in Pak-choi. Flowering is a key event in the life cycle of plants. Flowering time shows an extensive variation from different Pak-choi (Brassica rapa ssp. chinensis) cultivars. However, the regulation mechanism of flowering in Pak-choi remains rarely known. In this study, a systematic identification and functional analysis of a Pak-choi MADS Affecting Flowering (MAF) gene, BcMAF2, was carried out. BcMAF2 encoded a protein containing a conserved MADS-box domain, which was localized in the nucleus. QPCR analysis indicated that the expression of BcMAF2 was higher in the leaves and flowers. Overexpression of BcMAF2 in Arabidopsis showed that BcMAF2 repressed flowering, which was further confirmed by silencing endogenous BcMAF2 in Pak-choi. In addition, Tempranillo 1 (TEM1) expression was up-regulated and MAF2 expression was down-regulated in the BcMAF2-overexpressing Arabidopsis. The expression of BcMAF2 and BcTEM1 was down-regulated in BcMAF2-silencing Pak-choi plants. The yeast one-hybrid, dual luciferase and qPCR results revealed that BcMAF2 protein could directly bind to BcTEM1 promoter and activate its expression, which was not reported in Arabidopsis. Meanwhile, a self-inhibition was found in BcMAF2. Taken together, this work suggested that BcMAF2 could repress flowering by directly activating BcTEM1.


Assuntos
Brassica rapa/metabolismo , Flores/fisiologia , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Genes de Plantas , Luciferases/metabolismo , Modelos Biológicos , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Ligação Proteica , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Plântula/genética
20.
Food Chem ; 290: 201-207, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31000038

RESUMO

Cross breeding may create wider genetic variation than two parents used in hybridization, but breeding efforts towards starch quality improvement are less reported in potato. A cross was made between Zhongshu-3 and Favorita to select desired starch properties in progenies. Among 206 F1 clones with potential high yield, starch qualities such as apparent amylose content (AAC), pasting viscosity, and thermal properties were further evaluated. A wide variation was observed in different starch physicochemical indices for 206 potato accessions. Twenty clones with high/low AAC, peak viscosity and peak gelatinization temperature were selected and then grown at another location to evaluate the stability of the traits. Similar wide range of variation in the starch properties was observed. Cluster analysis based on starch properties of the 20 selected clones indicating relative stability of the starch property traits across different locations. New breeding lines identified have potential for application in food and other industries.


Assuntos
Variação Genética , Solanum tuberosum/metabolismo , Amido/química , Amilose/química , Análise por Conglomerados , Genótipo , Fenótipo , Estações do Ano , Plântula/genética , Plântula/metabolismo , Solanum tuberosum/genética , Amido/metabolismo , Temperatura Ambiente , Viscosidade
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