Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 12.002
Filtrar
1.
Gene ; 764: 145078, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32858175

RESUMO

In maize, eat rot and stalk rot caused by Fusarium verticillioides and Fusarium graminearum lead to contamination of moldy grains to produce mycotoxins. Identification of resistance genes against these pathogens for maize breeding is an effective way for disease control. Several 2-oxoglutarate-dependent dioxygenase (2OGD) proteins have been found to confer resistance to different pathogens in diverse plant species. However, little is known about the 2OGD superfamily in maize. Here, we identified 103 putative 2OGD genes in maize from a genome-wide analysis, and divided them into three classes - DOXA, DOXB, and DOXC. We further comprehensively investigated their gene structure, chromosome distribution, phylogenetic tree, gene-function enrichment, and expression profiles among different tissues. The genes encoding three 2OGD proteins, ACO, F3H, and NCS involved in ethylene biosynthesis, flavonoids biosynthesis, and alkaloids biosynthesis pathways, respectively, were identified to be induced by F. verticillioides and F. graminearum. The promoters of the three genes contain the binding sites for the transcription factor ZmDOF and ZmHSF, which are also induced by the two pathogens. The results imply that the three 2OGDs and the two transcription factors might be involved in the resistance to the two pathogens. This study provided a comprehensive understanding of the 2OGD superfamily in maize and laid the foundation for the further functional analysis of their roles in maize resistance to eat rot and stalk rot.


Assuntos
Dioxigenases/genética , Fusarium/imunologia , Proteínas de Plantas/genética , Zea mays/fisiologia , Sequência de Bases/genética , Sítios de Ligação/genética , Cromossomos de Plantas/genética , Coenzimas/metabolismo , Sequência Conservada/genética , Dioxigenases/imunologia , Dioxigenases/metabolismo , Resistência à Doença/genética , Evolução Molecular , Fusarium/patogenicidade , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas/fisiologia , Estudo de Associação Genômica Ampla , Ácidos Cetoglutáricos/metabolismo , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Caules de Planta/enzimologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/microbiologia , Regiões Promotoras Genéticas/genética , RNA-Seq , Fatores de Transcrição/metabolismo , Zea mays/microbiologia
2.
Food Chem ; 338: 127991, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32950867

RESUMO

Photoperiod and temperature are vital environmental factors that regulate plant developmental processes. However, the roles of these factors in garlic bulb enlargement are unclear. In this report, responses of garlic bulb morphology and physiology to combinations of photoperiod (light/dark: 10/14 h, 12/12 h, 14/10 h) and temperature (light/dark: 25/18 °C, 30/20 °C) were investigated. For garlic cultivar G103, bulb characteristics, phytohormones (IAA, ABA, ZT, tZR, JA), allicin and phenolic acids (p-coumaric and p-hydroxybenzoic) were highest under a photoperiod of 14 h at 30 °C. Maximum GA was observed under 14 h + 30 °C for cv. G2011-5. Maximum caffeic, ferulic and vanillic acids were detected for cv. G2011-5 at 14 h + 30 °C, 12 h + 25 °C and 14 h + 25 °C, respectively. Flavonoids (myricetin, quercetin, kaempferol and apigenin) were not detected in this trial. This is the first report describing the impact of long periods of light duration and higher temperatures on garlic morphology, phytohormones, phenolic acids and allicin content.


Assuntos
Alho/crescimento & desenvolvimento , Alho/efeitos da radiação , Fotoperíodo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/efeitos da radiação , Temperatura , Caules de Planta/química
3.
Nucleic Acids Res ; 49(1): 190-205, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33332564

RESUMO

Secondary wall thickening in the sclerenchyma cells is strictly controlled by a complex network of transcription factors in vascular plants. However, little is known about the epigenetic mechanism regulating secondary wall biosynthesis. In this study, we identified that ARABIDOPSIS HOMOLOG of TRITHORAX1 (ATX1), a H3K4-histone methyltransferase, mediates the regulation of fiber cell wall development in inflorescence stems of Arabidopsis thaliana. Genome-wide analysis revealed that the up-regulation of genes involved in secondary wall formation during stem development is largely coordinated by increasing level of H3K4 tri-methylation. Among all histone methyltransferases for H3K4me3 in Arabidopsis, ATX1 is markedly increased during the inflorescence stem development and loss-of-function mutant atx1 was impaired in secondary wall thickening in interfascicular fibers. Genetic analysis showed that ATX1 positively regulates secondary wall deposition through activating the expression of secondary wall NAC master switch genes, SECONDARY WALL-ASSOCIATED NAC DOMAIN PROTEIN1 (SND1) and NAC SECONDARY WALL THICKENING PROMOTING FACTOR1 (NST1). We further identified that ATX1 directly binds the loci of SND1 and NST1, and activates their expression by increasing H3K4me3 levels at these loci. Taken together, our results reveal that ATX1 plays a key role in the regulation of secondary wall biosynthesis in interfascicular fibers during inflorescence stem development of Arabidopsis.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Código das Histonas , Histona-Lisina N-Metiltransferase/fisiologia , Histonas/genética , Inflorescência/metabolismo , Proteínas de Plantas/genética , Caules de Planta/metabolismo , Fatores de Transcrição/fisiologia , Transcriptoma , Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/genética , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica de Plantas/genética , Ontologia Genética , Genes de Plantas , Histonas/metabolismo , Lignina/metabolismo , Proteínas de Plantas/metabolismo , Caules de Planta/ultraestrutura , RNA de Plantas/biossíntese , RNA de Plantas/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Xilanos/metabolismo
4.
Food Chem ; 334: 127589, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32707366

RESUMO

Postharvest, pea vine field residue (haulm) was steam-sterilised and then juiced; a chloroplast-rich fraction (CRF) was recovered from the juice by centrifugation. The stability of selected nutrients (ß-carotene, lutein, and α-tocopherol) in the freeze-dried CRF material was measured over 84 days; the impact of temperature (-20 °C, 4 °C, 25 °C and 40 °C), light and air on nutrient stability was established. All three nutrients were stable at -20 °C and 4 °C in the presence or absence of air; this stability was lost at higher temperatures in the presence of air. The extent and rate of nutrient breakdown significantly increased when the CRF samples were exposed to light. ß-Carotene appeared to be more susceptible to degradation than lutein and α-tocopherol at 40 °C in the presence of air, but when CRF was exposed to light all three nutrients measured were significantly broken down during storage at 25 °C or 40 °C, whether exposed to air or not.


Assuntos
Cloroplastos/química , Nutrientes/química , Ervilhas/química , Caules de Planta/química , Esterilização/métodos , Ar , Armazenamento de Alimentos , Liofilização , Luteína/análise , Luteína/química , Nutrientes/análise , Vapor , Temperatura , alfa-Tocoferol/análise , alfa-Tocoferol/química , beta Caroteno/análise , beta Caroteno/química
5.
Food Chem ; 339: 128081, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152874

RESUMO

In the present study, three-phase partitioning (TPP) coupled with gradient ethanol precipitation (GEP) was developed for the first time to extract and isolate polysaccharides (GPSs) from raw garlic (Allium sativum L.) bulbs. Four kinds of fructose polymers, namely, GPS35, GPS50, GPS65, and GPS80, were obtained at the final ethanol precipitation concentrations of 35%, 50%, 65%, and 80% (v/v), respectively, and their physicochemical characteristics and in vitro biological activities were investigated. Results indicated that GPS80 had higher carbohydrate (86.68% ± 0.90%) and uronic acid (12.89% ± 0.09%) contents, lower weight-average molecular weight (8.93 × 103 Da), and looser surface morphology than the other three GPSs. Furthermore, among the four GPSs, GPS80 exhibited the strongest antioxidant capacities, inhibitory effects on α-amylase and α-glycosidase, and nitric oxide stimulatory activity on RAW264.7 macrophage cells in vitro. Therefore, this study provides a simple and feasible technological strategy for producing bioactive polysaccharides from raw Allium vegetables.


Assuntos
Precipitação Química , Etanol/química , Alho/química , Caules de Planta/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fenômenos Químicos , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Peso Molecular , Polissacarídeos/isolamento & purificação , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/metabolismo
6.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3340-3348, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33314823

RESUMO

To reveal mechanisms underlying the dieback of Malus sieversii in degraded wild fruit forest in Ili valley of China, we compared the differences in stem hydraulic architecture, water transport effectiveness and safety, as well as their influencing factors among three growth classes of dead branches ratios, including Class Ⅰ (<20%), Class Ⅱ (40%-60%) and Class Ⅲ (>80%), respectively. With the increases in degradation degree of Xinjiang wild fruit forest, sapwood-specific hydraulic conductivity and leaf-specific hydraulic conductivity decreased, without significant differences among the three growth classes. Branch embolism at dusk and hydraulic safety significantly increased. The xylem water potential at 50% loss of hydraulic conductivity was -1.87, -1.35 and -0.53 MPa for Class Ⅰ, Ⅱ and Ⅲ, respectively. Predawn and midday leaf water potential and the hydraulic safety margin exhibited an order of Ⅰ>Ⅱ>Ⅲ. Xylem anatomical cha-racteristics and branch and leaf traits related to hydraulics were significantly different among the three growth classes. Results from correlation analysis revealed a weak tradeoff between xylem-specific hydraulic efficiency and xylem safety of M. sieversii. Stem hydraulic architecture of M. sieversii altered with the decline of Xinjiang wild apple forest. With increasing degrees of degradation, the severity of xylem embolisms aggravated, resistance to cavitation embolisms reduced, and the risk of water imbalance increased.


Assuntos
Malus , China , Florestas , Frutas , Folhas de Planta , Caules de Planta , Árvores , Água , Xilema
7.
PLoS One ; 15(10): e0239427, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33017404

RESUMO

Plants adapt to high altitudes by adjusting the characteristics of their above and underground organs. Identifying the species-specific plant traits changed in response to altitude is essential for understanding ecophysiological processes at the ecosystem level. Multiple studies analyzed the effects of altitude on above and underground organ traits in different species. Yet, little is known about those responses in the alpine Fritillaria przewalskii Maxim. (Liliaceae). F. przewalskii is a perennial medicinal plant with meager annual growth and vanishing wild populations. We analyzed leaf and bulb functional traits, and their allometric relationships in F. przewalskii plants grown at three altitudes: 3000, 2700, and 2400 m. Leaf thickness, leaf biomass, leaf biomass allocation, and the aboveground:underground ratio increased significantly with increasing altitude. Conversely, bulb allocation decreased at higher altitudes. The altitude influenced the allometric growth trajectories of specific leaf and bulb traits: higher altitudes led to thicker and broader leaves and changed the shape of the bulbs from more circular, which is ideal (at 2700 m), to more elongated (at 3000 m). Those variations had remarkable ecological significance. Hence, bulb biomass is the largest at 2700 m of altitude for which their vertical and longitudinal ratio is unaffected. which is economically favorable. Our findings show that F. przewalskii has a notable potential of growth and morphological plasticity along the altitude gradient and that 2700 m might be ideal for developing its artificial cultivation.


Assuntos
Altitude , Fritillaria/anatomia & histologia , Fritillaria/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Caules de Planta/anatomia & histologia , Caules de Planta/crescimento & desenvolvimento , Biomassa
8.
PLoS One ; 15(9): e0238703, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915871

RESUMO

The stem volume of commercial trees is an important variable that assists in decision making and economic analysis in forest management. Wood from forest plantations can be used for several purposes, which makes estimating multi-volumes for the same tree a necessary task. Defining its exploitation and use potential, such as the total and merchantable volumes (up to a minimum diameter of interest), with or without bark, is a possible work. The goal of this study was to use different strategies to model multi-volumes of the stem of eucalyptus trees. The data came from rigorous scaling of 460 felled trees stems from four eucalyptus clones in high forest and coppice regimes. The diameters were measured at different heights, with the volume of the sections obtained by the Smalian method. Data were randomly separated into fit and validation data. The single multi-volume model, volume-specific models, and the training of artificial neural networks (ANNs) were fitted. The evaluation criteria of the models were: coefficient of determination, root mean square error, mean absolute error, mean bias error, as well as graphical analysis of observed and estimated values and distribution of residuals. Additionally, the t-test (α = 0.05) was performed between the volume obtained in the rigorous scaling and estimated by each strategy with the validation data. Results showed that the strategies used to model different tree stem volumes are efficient. The actual and estimated volumes showed no differences. The multi-volume model had the most considerable advantage in volume estimation practicality, while the volume-specific models were more efficient in the accuracy of estimates. Given the conditions of this study, the ANNs are more suitable than the regression models in the estimation of multi-volumes of eucalyptus trees, revealing greater accuracy and practicality.


Assuntos
Biomassa , Eucalyptus/crescimento & desenvolvimento , Modelos Biológicos , Árvores/crescimento & desenvolvimento , Florestas , Redes Neurais de Computação , Caules de Planta/crescimento & desenvolvimento , Madeira/crescimento & desenvolvimento
9.
Plant Mol Biol ; 104(4-5): 429-450, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32808190

RESUMO

KEY MESSAGE: OsWRKY36 represses plant height and grain size by inhibiting gibberellin signaling. Plant height and grain size are important agronomic traits affecting yield in cereals, including rice. Gibberellins (GAs) are plant hormones that promote plant growth and developmental processions such as stem elongation and grain size. WRKYs are transcription factors that regulate stress tolerance and plant development including height and grain size. However, the relationship between GA signaling and WRKY genes is still poorly understood. Here, we characterized a small grain and semi-dwarf 3 (sgsd3) mutant in rice cv. Hwayoung (WT). A T-DNA insertion in the 5'-UTR of OsWRKY36 induced overexpression of OsWRKY36 in the sgsd3 mutant, likely leading to the mutant phenotype. This was confirmed by the finding that overexpression of OsWRKY36 caused a similar small grain and semi-dwarf phenotype to the sgsd3 mutant whereas knock down and knock out caused larger grain phenotypes. The sgsd3 mutant was also hyposensitive to GA and accumulated higher mRNA and protein levels of SLR1 (a GA signaling DELLA-like inhibitor) compared with the WT. Further assays showed that OsWRKY36 enhanced SLR1 transcription by directly binding to its promoter. In addition, we found that OsWRKY36 can protect SLR1 from GA-mediated degradation. We thus identified a new GA signaling repressor OsWRKY36 that represses GA signaling through stabilizing the expression of SLR1.


Assuntos
Oryza/crescimento & desenvolvimento , Oryza/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Regiões 5' não Traduzidas , DNA Bacteriano , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Mutação , Oryza/citologia , Fenótipo , Células Vegetais , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Caules de Planta/citologia , Caules de Planta/genética , Regiões Promotoras Genéticas , Estabilidade Proteica , Interferência de RNA , Sementes/genética , Sementes/crescimento & desenvolvimento , Transdução de Sinais , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
10.
Plant Mol Biol ; 104(3): 263-281, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32740898

RESUMO

KEY MESSAGE: Plant-specific Dof transcription factors VDOF1 and VDOF2 are novel regulators of vascular cell differentiation through the course of a lifetime in Arabidopsis, with shifting their transcriptional target genes. Vascular system is one of critical tissues for vascular plants to transport low-molecular compounds, such as water, minerals, and the photosynthetic product, sucrose. Here, we report the involvement of two Dof transcription factors, named VASCULAR-RELATED DOF1 (VDOF1)/VDOF4.6 and VDOF2/VDOF1.8, in vascular cell differentiation and lignin biosynthesis in Arabidopsis. VDOF genes were expressed in vascular tissues, but the detailed expression sites were partly different between VDOF1 and VDOF2. Vein patterning and lignin analysis of VDOF overexpressors and double mutant vdof1 vdof2 suggested that VDOF1 and VDOF2 would function as negative regulators of vein formation in seedlings, and lignin deposition in inflorescence stems. Interestingly, effects of VDOF overexpression in lignin deposition were different by developmental stages of inflorescence stems, and total lignin contents were increased and decreased in VDOF1 and VDOF2 overexpressors, respectively. RNA-seq analysis of inducible VDOF overexpressors demonstrated that the genes for cell wall biosynthesis, including lignin biosynthetic genes, and the transcription factor genes related to stress response and brassinosteroid signaling were commonly affected by VDOF1 and VDOF2 overexpression. Taken together, we concluded that VDOF1 and VDOF2 are novel regulators of vascular cell differentiation through the course of a lifetime, with shifting their transcriptional target genes: in seedlings, the VDOF genes negatively regulate vein formation, while at reproductive stages, the VDOF proteins target lignin biosynthesis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Diferenciação Celular/fisiologia , Lignina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Inflorescência , Mutação , Caules de Planta/citologia , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Sementes , Análise de Sequência
11.
PLoS One ; 15(8): e0230089, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760138

RESUMO

Ecological stoichiometric should be incorporated into management and nutrient impacted ecosystems dynamic to understand the status of ecosystems and ecological interaction. The present study focused on ecological stoichiometric characteristics of soil, and leaves, stems, and roots of different macrophytes after the banning of seine fishing in Shengjin Lake. For C, N, and P analysis from leaves, stems, roots, and soil to explore their stoichiometric ratio and deriving environmental forces, four dominant plant communities (Vallisneria natans, Zizania latifolia, Trapa natans and Carex schmidtii) were collected. The concentration of C, N, P and C: N: P ratio in leaves, stems, roots, and soil among the plant communities varied significantly. Along the depth gradient high C: N was measured in C.schmidtii soil (7.08±1.504) but not vary significantly (P >0.05). High C: P result was found in T.natans (81.14±43.88) and in V.natans soil (81.40±42.57) respectively with no significant difference (p>0.05). Besides, N: P ratio measured high in V. natans (13.7±4.05) and showed significant variation (P<0.05). High leaf C: N and N: P ratio was measured in C. schmidtii and V. natans respectively. Nevertheless, high leaf C: P ratio was measured in Z. latifolia. From the three studied organs, leaf C: N and N: P ratio showed high values compared to root and stems. The correlation analysis result showed that at 0-10cm depth soil organic carbon (SOC) correlated negatively with stem total phosphorus (STP), and root total nitrogen (RTN) (P<0.05) but positively strongly with leaf total phosphorus (LTP) and leaf total nitrogen (LTN) (P<0.01) respectively. Soil total nitrogen (STN) at 0-10cm strongly positively correlated with leaf total phosphorus (LTP) (P<0.01) and positively with RN: P and leaf total carbon (LTC) (P<0.05). Soil basic properties such as soil moisture content (SMC), bulky density (BD) and pH positively correlated with soil ecological stoichiometric characteristics. Redundancy analysis (RDA) result showed available nitrogen (AN), soil total nitrogen (STN), and available phosphorus (AP) were the potential determinants variables on plants stoichiometric characteristics.


Assuntos
Plantas/química , Solo/química , Carbono/análise , Carex (Planta) , China , Ecossistema , Eleocharis , Hydrocharitaceae , Lagos , Nitrogênio/análise , Fósforo/análise , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Poaceae , Áreas Alagadas
12.
PLoS One ; 15(7): e0236943, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735612

RESUMO

Halophyte Lobularia maritima LmSAP encodes an A20AN1 zinc-finger stress-associated protein which expression is up-regulated by abiotic stresses and heavy metals in transgenic tobacco. To deepen our understanding of LmSAP function, we isolated a 1,147 bp genomic fragment upstream of LmSAP coding sequence designated as PrLmSAP. In silico analyses of PrLmSAP revealed the presence of consensus CAAT and TATA boxes and cis-regulatory elements required for abiotic stress, phytohormones, pathogen, and wound responses, and also for tissue-specific expression. The PrLmSAP sequence was fused to the ß-glucuronidase (gusA) reporter gene and transferred to rice. Histochemical GUS staining showed a pattern of tissue-specific expression in transgenic rice, with staining observed in roots, coleoptiles, leaves, stems and floral organs but not in seeds or in the root elongation zone. Wounding strongly stimulated GUS accumulation in leaves and stems. Interestingly, we observed a high stimulation of the promoter activity when rice seedlings were exposed to NaCl, PEG, ABA, MeJA, GA, cold, and heavy metals (Al3+, Cd2+, Cu2+ and Zn2+). These results suggest that the LmSAP promoter can be a convenient tool for stress-inducible gene expression and is a potential candidate for crop genetic engineering.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Regiões Promotoras Genéticas , Plantas Tolerantes a Sal/genética , Estresse Fisiológico/genética , Dedos de Zinco/genética , Produtos Agrícolas/genética , Engenharia Genética , Glucuronidase/metabolismo , Metais Pesados/metabolismo , Especificidade de Órgãos , Oryza/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética
13.
PLoS Biol ; 18(8): e3000830, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32810128

RESUMO

Plants are attacked by herbivores, which often specialize on different tissues, and in response, have evolved sophisticated resistance strategies that involve different types of chemical defenses frequently targeted to different tissues. Most known phytohormones have been implicated in regulating these defenses, with jasmonates (JAs) playing a pivotal role in complex regulatory networks of signaling interactions, often generically referred to as "cross talk." The newly identified class of phytohormones, strigolactones (SLs), known to regulate the shoot architecture, remain unstudied with regard to plant-herbivore interactions. We explored the role of SL signaling in resistance to a specialist weevil (Trichobaris mucorea) herbivore of the native tobacco, Nicotiana attenuata, that attacks the root-shoot junction (RSJ), the part of the plant most strongly influenced by alterations in SL signaling (increased branching). As SL signaling shares molecular components, such as the core F-box protein MORE AXILLARY GROWTH 2 (MAX2), with another new class of phytohormones, the karrikins (KARs), which promote seed germination and seedling growth, we generated transformed lines, individually silenced in the expression of NaMAX2, DWARF 14 (NaD14: the receptor for SL) and CAROTENOID CLEAVAGE DIOXYGENASE 7 (NaCCD7: a key enzyme in SL biosynthesis), and KARRIKIN INSENSITIVE 2 (NaKAI2: the KAR receptor). The mature stems of all transgenic lines impaired in the SL, but not the KAR signaling pathway, overaccumulated anthocyanins, as did the stems of plants attacked by the larvae of weevil, which burrow into the RSJs to feed on the pith of N. attenuata stems. T. mucorea larvae grew larger in the plants silenced in the SL pathway, but again, not in the KAI2-silenced plants. These phenotypes were associated with elevated JA and auxin (indole-3-acetic acid [IAA]) levels and significant changes in the accumulation of defensive compounds, including phenolamides and nicotine. The overaccumulation of phenolamides and anthocyanins in the SL pathway-silenced plants likely resulted from antagonism between the SL and JA pathway in N. attenuata. We show that the repressors of SL signaling, suppressor of max2-like (NaSMXL6/7), and JA signaling, jasmonate zim-domain (NaJAZs), physically interact, promoting NaJAZb degradation and releasing JASMONATE INSENSITIVE 1 (JIN1/MYC2) (NaMYC2), a critical transcription factor promoting JA responses. However, the increased performance of T. mucorea larvae resulted from lower pith nicotine levels, which were inhibited by increased IAA levels in SL pathway-silenced plants. This inference was confirmed by decapitation and auxin transport inhibitor treatments that decreased pith IAA and increased nicotine levels. In summary, SL signaling tunes specific sectors of specialized metabolism in stems, such as phenylpropanoid and nicotine biosynthesis, by tailoring the cross talk among phytohormones, including JA and IAA, to mediate herbivore resistance of stems. The metabolic consequences of the interplay of SL, JA, and IAA signaling revealed here could provide a mechanism for the commonly observed pattern of herbivore tolerance/resistance trade-offs.


Assuntos
Herbivoria/fisiologia , Interações Hospedeiro-Parasita , Lactonas/metabolismo , Caules de Planta/metabolismo , Caules de Planta/parasitologia , Transdução de Sinais , Tabaco/metabolismo , Tabaco/parasitologia , Animais , Antocianinas/metabolismo , Ciclopentanos/metabolismo , Ácidos Indolacéticos/metabolismo , Larva , Metabolômica , Oxilipinas/metabolismo , Proteínas de Plantas/metabolismo , Interferência de RNA , Gorgulhos/fisiologia
14.
PLoS One ; 15(7): e0236565, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730299

RESUMO

Flavonoids are key components of licorice plant that directly affect its medicinal quality. Importantly, the MYB family of transcription factors serves to regulate the synthesis of flavonoids in plants. The MYB transcription factors represent one of the largest families of transcription factors in plants and play important roles in the process of plant growth and development. MYB gene expression is induced by a number of plant hormones, including the lipid-based hormone jasmonate (JA). Methyl jasmonate (MeJA) is an endogenous plant growth regulator that can induce the JA signaling pathway, which functions to regulate the synthesis of secondary metabolites, including flavonoids. In this study, MeJA was added to licorice cell suspensions, and RNA-seq analysis was performed to identify the differentially expressed genes. As a result, the MYB transcription factors GlMYB4 and GlMYB88 were demonstrated to respond significantly to MeJA induction. Subsequently, the GlMYB4 and GlMYB88 protein were shown to localize to the cell nucleus, and it was verified that GlMYB4 and GlMYB88 could positively regulate the synthesis of flavonoids in licorice cells. Overall, this research helps illustrate the molecular regulation of licorice flavonoid biosynthesis induced by MeJA.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Flavonoides/biossíntese , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glycyrrhiza uralensis/metabolismo , Oxilipinas/farmacologia , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Flavonoides/química , Glycyrrhiza uralensis/química , Glycyrrhiza uralensis/crescimento & desenvolvimento , Filogenia , Folhas de Planta/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Fatores de Transcrição/classificação , Fatores de Transcrição/genética
15.
Food Chem ; 333: 127506, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679417

RESUMO

Artichoke floral stems (AFS) food waste by-products were examined for their phytochemical constituents and their in vitro and in vivo biological activities. Although that the highest total phenol content and total flavonoid content were found in ethyl acetate extract, methanol extract possessed the strongest DPPH and ABTS radical scavenging activity, and showed the highest reducing ferric antioxidant power (FRAP). The anti-acetylcholinesterase activity was higher in butanol extract, whereas the ethyl acetate extract had the highest inhibitory effect on heat-induced protein denaturation. In alloxan-induced diabetic mice, the AFS methanol extract (AFSE) rich in caffeoylquinic acids and flavones reduced blood glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, creatinine, and improved liver, and renal antioxidative status. Administration of AFSE to diabetic mice reduced total cholesterol, triglycerides, LDL-cholesterol, and the atherogenic index of plasma (AIP) suggesting its hypolipidemic action. Overall, AFS could be considered as attractive source of health-promoting ingredients.


Assuntos
Cynara scolymus/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Alanina Transaminase , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Bactérias/efeitos dos fármacos , Glicemia/análise , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cynara scolymus/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Flavonoides/análise , Flores/química , Flores/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Fenóis/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/farmacologia , Caules de Planta/química , Caules de Planta/metabolismo , Espectrometria de Massas por Ionização por Electrospray
16.
Food Chem ; 332: 127372, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615381

RESUMO

The physicochemical and physiological properties of soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) from bamboo shoots were investigated in present study. IDF showed better adsorption capacity than the corresponding SDF from the same species. Microstructure observation results indicated that the surface of IDF was porous, whereas the SDF was relatively flat and compact. The cholesterol-adsorption capacities of IDF and SDF from Fargesia spathacea were relatively higher than the other species. Both SDF and IDF from F. spathacea showed potential prebiotic effects, although the Lactobacillus and Bifidobacterium promotion effects of SDF were relatively stronger than IDF. Compared with control, the concentration of total short chain fatty acids in IDF and SDF supplement groups were increased by 1.28 and 0.71 folds, respectively. These results suggested that F. spathacea dietary fibers with strong cholesterol-adsorption activity and prebiotic potential, could be used as a bioactive ingredient in functional foods production.


Assuntos
Anticolesterolemiantes/química , Anticolesterolemiantes/farmacologia , Fibras na Dieta/farmacologia , Caules de Planta/química , Poaceae/química , Prebióticos , Fenômenos Químicos , Suplementos Nutricionais , Alimento Funcional/análise
17.
PLoS One ; 15(7): e0236424, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730292

RESUMO

Grapevines, although adapted to occasional drought or salt stress, are relatively sensitive to growth- and yield-limiting salinity stress. To understand the molecular mechanisms of salt tolerance and endoplasmic reticulum (ER) stress and identify genes commonly regulated by both stresses in grapevine, we investigated transcript profiles in leaves of the salt-tolerant grapevine rootstock 1616C under salt- and ER-stress. Among 1643 differentially expressed transcripts at 6 h post-treatment in leaves, 29 were unique to ER stress, 378 were unique to salt stress, and 16 were common to both stresses. At 24 h post-treatment, 243 transcripts were unique to ER stress, 1150 were unique to salt stress, and 168 were common to both stresses. GO term analysis identified genes in categories including 'oxidative stress', 'protein folding', 'transmembrane transport', 'protein phosphorylation', 'lipid transport', 'proteolysis', 'photosynthesis', and 'regulation of transcription'. The expression of genes encoding transporters, transcription factors, and proteins involved in hormone biosynthesis increased in response to both ER and salt stresses. KEGG pathway analysis of differentially expressed genes for both ER and salt stress were divided into four main categories including; carbohydrate metabolism, amino acid metabolism, signal transduction and lipid metabolism. Differential expression of several genes was confirmed by qRT-PCR analysis, which validated our microarray results. We identified transcripts for genes that might be involved in salt tolerance and also many genes differentially expressed under both ER and salt stresses. Our results could provide new insights into the mechanisms of salt tolerance and ER stress in plants and should be useful for genetic improvement of salt tolerance in grapevine.


Assuntos
Estresse do Retículo Endoplasmático/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Raízes de Plantas/genética , Estresse Salino/genética , Vitis/genética , Metabolismo dos Carboidratos/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Análise de Sequência com Séries de Oligonucleotídeos , Osmose , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Caules de Planta/efeitos dos fármacos , Caules de Planta/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Estresse Salino/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Fatores de Transcrição/metabolismo , Tunicamicina/farmacologia
18.
Nature ; 584(7819): 109-114, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32669710

RESUMO

The size of plants is largely determined by growth of the stem. Stem elongation is stimulated by gibberellic acid1-3. Here we show that internode stem elongation in rice is regulated antagonistically by an 'accelerator' and a 'decelerator' in concert with gibberellic acid. Expression of a gene we name ACCELERATOR OF INTERNODE ELONGATION 1 (ACE1), which encodes a protein of unknown function, confers cells of the intercalary meristematic region with the competence for cell division, leading to internode elongation in the presence of gibberellic acid. By contrast, upregulation of DECELERATOR OF INTERNODE ELONGATION 1 (DEC1), which encodes a zinc-finger transcription factor, suppresses internode elongation, whereas downregulation of DEC1 allows internode elongation. We also show that the mechanism of internode elongation that is mediated by ACE1 and DEC1 is conserved in the Gramineae family. Furthermore, an analysis of genetic diversity suggests that mutations in ACE1 and DEC1 have historically contributed to the selection of shorter plants in domesticated populations of rice to increase their resistance to lodging, and of taller plants in wild species of rice for adaptation to growth in deep water. Our identification of these antagonistic regulatory factors enhances our understanding of the gibberellic acid response as an additional mechanism that regulates internode elongation and environmental fitness, beyond biosynthesis and gibberellic acid signal transduction.


Assuntos
Giberelinas/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Aclimatação , Mutação , Oryza/genética , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Locos de Características Quantitativas , Transdução de Sinais
19.
PLoS One ; 15(7): e0236530, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706831

RESUMO

Apple trees grafted on different rootstock types, including vigorous rootstock (VR), dwarfing interstock (DIR), and dwarfing self-rootstock (DSR), are widely planted in production, but the molecular determinants of tree branch architecture growth regulation induced by rootstocks are still not well known. In this study, the branch growth phenotypes of three combinations of 'Fuji' apple trees grafted on different rootstocks (VR: Malus baccata; DIR: Malus baccata/T337; DSR: T337) were investigated. The VR trees presented the biggest branch architecture. The results showed that the sugar content, sugar metabolism-related enzyme activities, and hormone content all presented obvious differences in the tender leaves and buds of apple trees grafted on these rootstocks. Transcriptomic profiles of the tender leaves adjacent to the top buds allowed us to identify genes that were potentially involved in signaling pathways that mediate the regulatory mechanisms underlying growth differences. In total, 3610 differentially expressed genes (DEGs) were identified through pairwise comparisons. The screened data suggested that sugar metabolism-related genes and complex hormone regulatory networks involved the auxin (IAA), cytokinin (CK), abscisic acid (ABA) and gibberellic acid (GA) pathways, as well as several transcription factors, participated in the complicated growth induction process. Overall, this study provides a framework for analysis of the molecular mechanisms underlying differential tree branch growth of apple trees grafted on different rootstocks.


Assuntos
Regulação da Expressão Gênica de Plantas , Malus/genética , Transdução de Sinais/genética , Açúcares/metabolismo , Ácido Abscísico/análise , Ácido Abscísico/metabolismo , Cromatografia Líquida de Alta Pressão , Citocininas/análise , Citocininas/metabolismo , Flores/genética , Flores/metabolismo , Giberelinas/análise , Giberelinas/metabolismo , Ácidos Indolacéticos/análise , Ácidos Indolacéticos/metabolismo , Malus/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/fisiologia , RNA de Plantas/genética , RNA de Plantas/metabolismo , Açúcares/análise , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
20.
J Food Sci ; 85(6): 1827-1833, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32476136

RESUMO

The effects of superfine grinding on the physicochemical and functional properties of asparagus pomace were investigated. The results showed that in terms of the specific surface area, water solubility, soluble dietary fiber content, and ratio of insoluble dietary fiber to soluble dietary fiber, finer samples usually possessed better physicochemical properties compared with coarse samples. However, grinding samples excessively to produce small particle sizes could reduce the water-holding capacity, oil-binding capacity, and swelling capacity. In addition, the extraction of both free and bound phenolics in asparagus pomace powder samples and the samples' absorption of both nitrite ion and glucose showed typical bell-shaped curves, demonstrating that superfine grinding could significantly impact the various properties of asparagus pomace. This study should provide insights into the effect of micronization on the functionalities of fiber-rich food materials. PRACTICAL APPLICATION: This article deals with the effects of superfine grinding on the physicochemical and functional properties of asparagus pomace. The results showed that the properties of asparagus pomace did not always improve gradually with decreasing particle size. With a decrease in granularity, some parameters showed a bell-shaped curve whereas others initially increased and then stabilized, indicating that in actual production, the crushing particle size should be determined according to actual needs or target parameters.


Assuntos
Asparagus (Planta)/química , Manipulação de Alimentos/métodos , Extratos Vegetais/química , Fibras na Dieta/análise , Tamanho da Partícula , Fenóis/química , Caules de Planta/química , Pós/química , Solubilidade , Resíduos/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA