RESUMEN
Muscadine grapes are characterized by their large and abundant seeds and hard and thick skins that contain significant amounts of dietary fiber (DF). The current study investigated the chemical constituents, molecular architecture, and physicochemical attributes of DF derived from Muscadine grapes (Granny Val and Alachua) and compared them with those derived from Shine Muscat and Kyoho. Using a combined enzymatic method, the total dietary fiber (TDF) was extracted and divided into two parts: soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). TDF (mainly IDF, with a small fraction of SDF) was dominated by cellulose, followed by pectin and hemicellulose. In addition, Granny Val and Alachua had a significantly higher abundance of TDF and IDF compared with Shine Muscat and Kyoho. Moreover, Shine Muscat had significantly the highest abundance of SDF among the four grape varieties. Of note, IDF from Granny Val and Alachua exhibited a complex and dense texture on its surface, and notably outperformed Shine Muscat and Kyoho in terms of cholesterol, fatty acid, heavy metal adsorption, and antioxidant activity. Collectively, Muscadine grapes, i.e., Granny Val and Alachua in the current study, possessed elevated DF levels (predominantly IDF), and their enhanced bioactivity underscored their potential as a potential food ingredient for further use.
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Fibras de la Dieta , Vitis , Vitis/química , Fibras de la Dieta/análisis , Antioxidantes/química , Antioxidantes/análisis , Celulosa/químicaRESUMEN
Root-zone restriction induces physiological stress on roots, thus limiting the vegetative and enhancing reproductive development, which promotes fruit quality and growth. Numerous bacterial-related growth-promoting, stress-mitigating, and disease-prevention activities have been described, but none in root-restricted cultivation. The study aimed to understand the activities of grapevine bacterial communities and plant-bacterial relationships to improve fruit quality. We used High-throughput sequencing, edaphic soil factors, and network analysis to explore the impact of restricted cultivation on the diversity, composition and network structure of bacterial communities of rhizosphere soil, roots, leaves, flowers and berries. The bacterial richness, diversity, and networking were indeed regulated by root-zone restriction at all phenological stages, with a peak at the veraison stage, yielding superior fruit quality compared to control plants. Moreover, it also handled the nutrient availability in treated plants, such as available nitrogen (AN) was 3.5, 5.7 and 0.9 folds scarcer at full bloom, veraison and maturity stages, respectively, compared to control plants. Biochemical indicators of the berry have proved that high-quality berry is yielded in association with the bacteria. Cyanobacteria were most abundant in the phyllosphere, Proteobacteria in the rhizosphere, and Firmicutes and Bacteroidetes in the endosphere. These bacterial phyla were most correlated and influenced by different soil factors in control and treated plants. Our findings are a comprehensive approach to the implications of root-zone restriction on the bacterial microbiota, which will assist in directing a more focused procedure to uncover the precise mechanism, which is still undiscovered.
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Microbiota , Suelo , Suelo/química , Microbiología del Suelo , Rizosfera , Microbiota/fisiología , Bacterias/genética , Plantas , Raíces de Plantas/microbiologíaRESUMEN
BACKGROUND: Mitochondrial transcription termination factor (mTERF) is a large gene family which plays a significant role during plant growth under various environmental stresses. However, knowledge of mTERF genes in grapevine (Vitis L.) is limited. RESULTS: In this research, a comprehensive analysis of grape mTERF (VvmTERF) genes, including chromosome locations, phylogeny, protein motifs, gene structures, gene duplications, synteny analysis and expression profiles, was conducted. As a result, a total of 25 mTERF genes were identified from the grape genome, which are distributed on 13 chromosomes with diverse densities and segmental duplication events. The grape mTERF gene family is classified into nine clades based on phylogenetic analysis and structural characteristics. These VvmTERF genes showed differential expression patterns in response to multiple phytohormone treatments and biotic stresses, including treatments with abscisic acid and methyl jasmonate, and inoculation of Plasmopara viticola and Erysiphe necator. CONCLUSIONS: These research findings, as the first of its kind in grapevine, will provide useful information for future development of new stress tolerant grape cultivars through genetic manipulation of VvmTERF genes.
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Vitis , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Vitis/genética , Vitis/metabolismoRESUMEN
BACKGROUND: The root-zone restriction cultivation technique is used to achieve superior fruit quality at the cost of limited vegetative and enhanced reproductive development of grapevines. Fungal interactions and diversity in grapevines are well established; however, our knowledge about fungal diversity under the root-zone restriction technique is still unexplored. To provide insights into the role of mycobiota in the regulation of growth and fruit quality of grapevine under root-zone restriction, DNA from rhizosphere and plant compartments, including white roots (new roots), leaves, flowers, and berries of root-zone restricted (treatment) and conventionally grown plants (control), was extracted at three growth stages (full bloom, veraison, and maturity). RESULTS: Diversity analysis based on the ITS1 region was performed using QIIME2. We observed that the root-zone restriction technique primarily affected the fungal communities of the soil and plant compartments at different growth stages. Interestingly, Fusarium, Ilyonectria, Cladosporium and Aspergillus spp observed in the rhizosphere overlapped with the phyllosphere at all phenological stages, having distinctive abundance in grapevine habitats. Peak richness and diversity were observed in the rhizosphere at the full bloom stage of control plants, white roots at the veraison stage of treatment, leaves at the maturity stage of treatment, flowers at the full bloom stage and berries at the veraison stage of control plants. Except for white roots, the diversity of soil and plant compartments of treated plants tended to increase until maturity. At the maturity stage of the treated and control plants, the abundance of Aspergillus spp. was 25.99 and 29.48%, respectively. Moreover, the total soluble sugar content of berries was 19.03 obrix and 16 obrix in treated and control plants, respectively, at the maturity stage. CONCLUSIONS: This is the first elucidative study targeting the fungal diversity of conventional and root-restricted cultivation techniques in a single vineyard. Species richness and diversity are affected by stressful cultivation known as root zone restriction. There is an association between the abundance of Aspergillus spp. and fruit quality because despite causing stress to the grapevine, superior quality of fruit is retrieved in root-zone restricted plants.
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Hongos/aislamiento & purificación , Micobioma , Raíces de Plantas/microbiología , Vitis/crecimiento & desarrollo , Flores/crecimiento & desarrollo , Flores/microbiología , Frutas/crecimiento & desarrollo , Frutas/microbiología , Hongos/clasificación , Hongos/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología , Raíces de Plantas/crecimiento & desarrollo , Rizosfera , Microbiología del Suelo , Vitis/microbiologíaRESUMEN
The oomycete pathogen Hyaloperonospora arabidopsidis delivers diverse effector proteins into host plant cells to suppress the plant's innate immunity. In this study, we investigate the mechanism of action of a conserved RxLR effector, HaRxLL470, in suppressing plant immunity. Genomic, molecular and biochemical analyses were performed to investigate the function of HaRxLL470 and the mechanism of the interaction between HaRxLL470 and the target host protein during H. arabidopsidis infection. We report that HaRxLL470 enhances plant susceptibility to H. arabidopsidis isolate Noco2 by interacting with the host photomorphogenesis regulator protein HY5. Our results demonstrate that HY5 is not only an important component in the regulation of light signalling, but also positively regulates host plant immunity against H. arabidopsidis by transcriptional activation of defense-related genes. We show that the interaction between HaRxLL470 and HY5 compromises the function of HY5 as a transcription factor by attenuating its DNA-binding activity. The present study demonstrates that HY5 positively regulates host plant defense against H. arabidopsidis whereas HaRxLL470, a conserved RxLR effector across oomycete pathogens, enhances pathogenicity by interacting with HY5 and suppressing transcriptional activation of defense-related genes.
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Proteínas de Arabidopsis , Arabidopsis , Oomicetos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , ADN , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Patógeno , Oomicetos/metabolismo , Enfermedades de las Plantas , Inmunidad de la PlantaRESUMEN
One of the biggest challenges in clonal propagation of grapevine (Vitis vinifera) is difficulty of rooting. Adventitious root initiation and development are the critical steps in the cutting and layering process of grapevine, but the molecular mechanism of these processes remains unclear. Previous reports have found that microRNA (miRNA)-encoded peptides (miPEPs) can regulate plant root development by increasing the transcription of their corresponding primary miRNA. Here, we report the role of a miPEP in increasing adventitious root formation in grapevine. In this study, we performed a global analysis of miPEPs in grapevine and characterized the function of vvi-miPEP171d1, a functional, small peptide encoded by primary-miR171d. There were three small open reading frames in the 500-bp upstream sequence of pre-miR171d. One of them encoded a small peptide, vvi-miPEP171d1, which could increase the transcription of vvi-MIR171d Exogenous application of vvi-miPEP171d1 to grape tissue culture plantlets promoted adventitious root development by activating the expression of vvi-MIR171d Interestingly, neither exogenous application of the vvi-miPEP171d1 peptide nor overexpression of the vvi-miPEP171d1 coding sequence resulted in phenotypic changes in Arabidopsis (Arabidopsis thaliana). Similarly, application of synthetic ath-miPEP171c, the small peptide encoded by the Arabidopsis ortholog of vvi-MIR171d, inhibited the growth of primary roots and induced the early initiation of lateral and adventitious roots in Arabidopsis, while it had no effect on grape root development. Our findings reveal that miPEP171d1 regulates root development by promoting vvi-MIR171d expression in a species-specific manner, further enriching the theoretical research into miPEPs.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , MicroARNs/metabolismo , Raíces de Plantas/metabolismo , Vitis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , Fenotipo , Raíces de Plantas/genética , Vitis/genéticaRESUMEN
Circular RNAs (circRNAs) are widely distributed and play essential roles in a series of developmental processes, although none have been identified or characterized in grapevines (Vitis vinifera). In this study, we characterized the function of grape circRNA and uncovered thousands of putative back-splicing sites by global transcriptome analysis. Our results indicated that several reported circRNA prediction algorithms should be used simultaneously to obtain comprehensive and reliable circRNA predictions in plants. Furthermore, the length of introns flanking grape circRNAs was closely related to exon circularization. Although the longer introns flanking grape circRNAs appeared to circularize more efficiently, a 20- to 50-nt region seemed large enough to drive grape circRNA biogenesis. In addition, the endogenous introns flanking circularized exon(s) in conjunction with reverse complementary sequences could support the accurate and efficient circularization of various exons in grape, which constitutes a new tool for exploring the functional consequences caused by circRNA expression. Finally, we identified 475 differentially expressed circRNAs in grape leaves under cold stress. Overexpression of Vv-circATS1, a circRNA derived from glycerol-3-P acyltransferase, improved cold tolerance in Arabidopsis (Arabidopsis thaliana), while the linear RNA derived from the same sequence cannot. These results indicate the functional difference between circRNA and linear RNA, and provide new insight into plant abiotic stress resistance.
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Clonación Molecular , Frío , ARN Circular/genética , Vitis/genética , Vitis/fisiología , Arabidopsis/genética , Arabidopsis/fisiología , Secuencia de Bases , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Genoma de Planta , Intrones/genética , MicroARNs/genética , MicroARNs/metabolismo , Plantas Modificadas Genéticamente , ARN Circular/metabolismo , Estrés Fisiológico/genéticaRESUMEN
Root restriction cultivation (RRC) can influence plant root architecture, but its root phenotypic changes and molecular mechanisms are still unknown. In this study, phenotype observations of grapevine root under RRC and control cultivation (nRC) at 12 time points were conducted, and the root phenotype showed an increase of adventitious and lateral root numbers and root tip degeneration after RRC cultivation from 70 days after planting (DAP). The 70 and 125 DAP sampling of two different cultivations, named nR70, RR70, nR125, and RR125, were selected for small RNA sequencing. A total of 153 known miRNAs and 119 predicted novel miRNAs were obtained. Furthermore, BLAST was used to predict the novel miRNAs with miRBase databases using the default parameters; 96 of the 119 predicted novel miRNAs were similar to other species, and the remaining 23 grapevine-specific novel miRNAs were obtained. There were 26, 33, 26, and 32 miRNAs that were differentially expressed in different comparison groups (RR70 vs. nR70, RR125 vs. nR125, nR125 vs. nR70 and RR125 vs. RR70). Target genes prediction of differentially expressed miRNAs was annotated on a variety of biological processes, and 24 participated in root development. Moreover, multiple miRNAs were found to jointly regulate lateral root development under root restriction conditions. The miRNA expression pattern comparison between RRC and nRC may provide a framework for the future analysis of miRNAs associated with root development in grapevine.
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Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/genética , ARN de Planta/genética , Análisis de Secuencia de ARN , Vitis/genética , Secuencia de Bases , Análisis por Conglomerados , Ontología de Genes , MicroARNs/metabolismo , Fenotipo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN de Planta/metabolismoRESUMEN
Root restriction cultivation leads to early maturation and quality improvement, especially in the anthocyanin content in grapevine. However, the molecular mechanisms that underlie these changes have not been thoroughly elucidated. In this study, four small RNA libraries were constructed, which included the green soft stage (GS) and ripe stage (RS) of 'Muscat' (Vitis vinifera L.) grape berries that were grown under root restriction (RR) and in traditional cultivation (no root restriction, CK). A total of 162 known miRNAs and 14 putative novel miRNAs were detected from the four small RNA libraries by high-throughput sequencing. An analysis of differentially expressed miRNAs (DEMs) revealed that 13 miRNAs exhibited significant differences in expression between RR and CK at the GS and RS stages, respectively. For different developmental stages of fruit, 23 and 34 miRNAs showed expression differences between the GS and RS stages in RR and CK, respectively. The expression patterns of the eight DEMs and their targets were verified by qRT-PCR, and the expression profiles of target genes were confirmed to be complementary to the corresponding miRNAs in RR and CK. The function of Vvi-miR828, which showed the down regulated expression in the RS stage under root restriction, was identified by gene transformation in Arabidopsis. The anthocyanin content significantly decreased in transgenic lines, which indicates the regulatory capacity of Vvi-miR828 in fruit coloration. The miRNA expression pattern comparison between RR and CK might provide a means of unraveling the miRNA-mediated molecular process regulating grape berry development under root restricted cultivation.
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Frutas/genética , Frutas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Vitis/genética , Vitis/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , ARN de Planta/genética , ARN de Planta/metabolismo , Análisis de Secuencia de ARNRESUMEN
We present an in-depth analysis of aroma profiles and sensory attributes, employing solid-phase microextraction gas chromatography/mass spectrometry (SPME-GC-MS) to identify the key compounds driving consumer preference in 19 unfamiliar cultivars. In combination with popular cultivars, we identified a total of 100 compounds in all table grapes, of which 26 key volatiles were correlated with consumer liking. Based on this relationship, five aroma combinations (AC) were formulated, wherein 33 compounds contributed to aroma intensity, and thus, were viewed as active volatiles. The fruity, floral, and sweet aromas were further divided into secondary aromatic series, of which the apple, citrus, orange, rose, geranium, violet, and honey aromas constituted the predominant series in unfamiliar cultivars. Xiangyue and Heikuixiang emerged as the preferred table grapes according to our analysis. By comparison, the popular cultivars showed relatively fewer volatiles, but their contents were much greater than the large number of volatiles identified in the unfamiliar cultivars.
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Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/análisis , Vitis/química , HumanosRESUMEN
BACKGROUND: Flavan-3-ol compounds are important secondary metabolites which show high antioxidant activity and are responsible for bitterness and astringency of food products. The aim of this work was to evaluate the potential for selecting grape materials with higher seed flavanol content from a breeding population. The composition and content of flavan-3-ols from 151 genotypes obtained from crossing wine grape varieties was evaluated by UPLC in three consecutive years. RESULTS: Chromatograms of flavan-3-ol compounds showed the same 12 compounds for all samples, but quantitative differences were observed between genotypes as well as parental varieties. The most abundant compounds were (-)-epicatechin and (+)-catechin followed by proanthocyanidins A2 and B2. Progeny showed higher values than the parental genotypes for every detected compound indicating directional transgressive segregation. With these results genotypes with as much as five times more flavanols than their parents could be identified. The year effect was significant; however, high correlations between years for each compound indicated that there is a strong genetic component in the determination of flavanol content. CONCLUSION: Higher contents of seed flavan-3-ols can be obtained by hybridisation, and those genotypes could be used for extracting healthy phytochemicals, adding value to seeds as a sub-product in wine elaboration. © 2016 Society of Chemical Industry.
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Flavonoides/análisis , Semillas/química , Semillas/genética , Vitis/genética , Antioxidantes/análisis , Catequina/análisis , Cromatografía Líquida de Alta Presión , Cruzamientos Genéticos , Genotipo , Hibridación Genética , Extractos Vegetales/química , Proantocianidinas/análisis , Especificidad de la Especie , Vitis/química , VinoRESUMEN
Pears are one of the most popular nutrient-rich fruits in the world. The pear core and mesocarp have significantly different metabolism, although they display similar profiles. Most strikingly, the core is more acidic in taste. Our results showed that there is more titrated acid but lower total soluble solids in the core compared to the mesocarp, and the content of citric acid was more than 17-fold higher in the core compared to the mesocarp at the ripening stage. Proteomics was used to investigate the difference between core and mesocarp tissues during "Cuiguan" pear ripening. Fifty-four different protein expression patterns were identified in the core and mesocarp. In general, common variably expressed proteins between the core and mesocarp were associated with important physiological processes, such as glycolysis, pyruvate metabolic processes, and oxidative stress. Further, protein level associated qRT-PCR verification revealed a higher abundance of fructose-bisphosphate aldolase and NADP-dependent malic enzymes, which may play a role in the low acid content in the mesocarp, whereas a higher abundance of disulfide isomerase-like 2-2 and calcium-dependent lipid-binding in the core may explain why it is less prone to accumulate sugar. The different levels of a few typical ROS scavenger enzymes suggested that oxidative stress is higher in the core than in the mesocarp. This study provides the first characterization of the pear core proteome and a description of its variation compared to the mesocarp during ripening.
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Frutas/metabolismo , Proteínas de Plantas/metabolismo , Pyrus/metabolismo , Electroforesis en Gel Bidimensional/métodos , Frutas/fisiología , Regulación de la Expresión Génica de las Plantas , Monosacáridos/metabolismo , Proteínas de Plantas/análisis , Proteínas de Plantas/genética , Proteómica/métodos , Pyrus/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Estrés Fisiológico/fisiologíaRESUMEN
High temperature stress is one of the primary abiotic stresses that restrict fruit tree production. Grapevine (Vitis vinifera) with high economic value throughout the world is a cultivated fruit crop, and its growth and development is often influenced by high temperature stress. Studying the heat stress-response mechanism of grapevine has great significance for understanding the acclimation to heat stress. In this study, we identified a series of heat stress responsive miRNAs and analyzed their function during the heat tolerance response. CK (control group, 25 °C) and heat treatment stress (TS, 45 °C) small RNA (sRNA) libraries were constructed and sequenced by high-throughput sequencing in 'Thompson seedless' grapevine. 873 known-miRNAs and 86 novel-miRNAs were identified, of which 88 known and three novel miRNAs were expressed differentially under heat stress. 322 genes were predicted to be targeted by the miRNAs. Eight selected miRNAs and its targets were confirmed by real time quantitative PCR (RT - qPCR), indicating that these "miRNA - target" were responsive to heat stress. In addition, most of the predicted target genes were negatively regulated by corresponding miRNAs. Gene function and pathway analyses indicated that these genes probably play crucial roles in heat stress tolerance. Vvi-miR167b transiently overexpression in grapevine leaves decreased target gene vvARF6, vvARF6-like and vvARF8 expression. The function of vvi-miR167 was verified by ectopic transformation in Arabidopsis thaliana, and the heat tolerance in transgenic lines was enhanced significantly, suggesting that the vvi-miR167 plays a positive regulatory role in grape thermostability. Comparison of miRNA expression patterns between heat treatment stress and CK can help elucidate the heat stress response and resistance mechanisms in grapes. In conclusion, these results gave us useful information to better understand the heat stress-response during domestication as well as for breeding new cultivars with heat stress resistance in fruit trees.
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MicroARNs , Vitis , MicroARNs/genética , Regulación de la Expresión Génica de las Plantas , Fitomejoramiento , Secuencia de Bases , Respuesta al Choque Térmico , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Vitis/genéticaRESUMEN
Circular RNAs (circRNAs) serve as covalently closed single-stranded RNAs and have been proposed to influence plant development and stress resistance. Grapevine is one of the most economically valuable fruit crops cultivated worldwide and is threatened by various abiotic stresses. Herein, we reported that a circRNA (Vv-circPTCD1) processed from the second exon of the pentatricopeptide repeat family gene PTCD1 was preferentially expressed in leaves and responded to salt and drought but not heat stress in grapevine. Additionally, the second exon sequence of PTCD1 was highly conserved, but the biogenesis of Vv-circPTCD1 is species-dependent in plants. It was further found that the overexpressed Vv-circPTCD1 can slightly decrease the abundance of the cognate host gene, and the neighboring genes are barely affected in the grapevine callus. Furthermore, we also successfully overexpressed the Vv-circPTCD1 and found that the Vv-circPTCD1 deteriorated the growth during heat, salt, and drought stresses in Arabidopsis. However, the biological effects on grapevine callus were not always consistent with those of Arabidopsis. Interestingly, we found that the transgenic plants of linear counterpart sequence also conferred the same phenotypes as those of circRNA during the three stress conditions, no matter what species it is. Those results imply that although the sequences are conserved, the biogenesis and functions of Vv-circPTCD1 are species-dependent. Our results indicate that the plant circRNA function investigation should be conducted in homologous species, which supports a valuable reference for further plant circRNA studies.
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The root system is essential for the stable growth of plants. Roots help anchor plants in the soil and play a crucial role in water uptake, mineral nutrient absorption and endogenous phytohormone formation. Root-restriction (RR) cultivation, a powerful technique, confines plant roots to a specific soil space. In the present study, roots of one-year-old "Muscat Hamburg" grapevine under RR and control (nR) treatments harvested at 70 and 125 days after planting were used for transcriptome sequencing, and in total, 2031 (nR7 vs. nR12), 1445 (RR7 vs. RR12), 1532 (nR7 vs. RR7), and 2799 (nR12 vs. RR12) differentially expressed genes (DEGs) were identified. Gene Ontology (GO) enrichment analysis demonstrated that there were several genes involved in the response to different phytohormones, including abscisic acid (ABA), auxin (IAA), ethylene (ETH), gibberellins (GAs), and cytokinins (CTKs). Among them, multiple genes, such as PIN2 and ERF113, are involved in regulating vital plant movements by various phytohormone pathways. Moreover, following RR cultivation, DEGs were enriched in the biological processes of plant-type secondary cell wall biosynthesis, the defense response, programmed cell death involved in cell development, and the oxalate metabolic process. Furthermore, through a combined analysis of the transcriptome and previously published microRNA (miRNA) sequencing results, we found that multiple differentially expressed miRNAs (DEMs) and DEG combinations in different comparison groups exhibited opposite trends, indicating that the expression levels of miRNAs and their target genes were negatively correlated. Furthermore, RR treatment indeed significantly increased the ABA content at 125 days after planting and significantly decreased the IAA content at 70 days after planting. Under RR cultivation, most ABA biosynthesis-related genes were upregulated, while most IAA biosynthesis-related genes were downregulated. These findings lay a solid foundation for further establishing the network through which miRNAs regulate grapevine root development through target genes and for further exploring the molecular mechanism through which endogenous ABA and IAA regulate root architecture development in grapevine.
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This study characterized growth characteristics and cellular details employing microscopy techniques in hydroponically-grown Ca2+-sufficient and Ca2+-deficient grapevines (Vitis vinifera) in a glasshouse. The Ca2+-deficient vines exhibited significant reductions in shoot length, shoot and trunk fresh weights, leaf area, chlorophyll, which eventually led to drooping, yellowing, and chlorosis of leaves. Roots were less dense and primarily dark and necrotic. Furthermore, their xylem vessels were small, polygonal, and appeared to be collapsed yet increased in number and developed lateral roots. Despite such alterations, the anatomical organization of leaves was not affected, yet they developed with more xylem vessels with thick walls and lignin in their mesophyll and vascular tissues. The chloroplasts in internodes' chlorenchyma, phloem, and cambium underwent significant ultrastructural modifications. The concentrations of macro and micronutrients varied significantly among the roots, trunk, canes, and leaves, including the growth characteristics. These structural and growth modifications of calcium deficiency enable us to understand better the link between the symptoms and functions and for a holistic understanding of Ca2+ functionalities.
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Calcio , Vitis , Floema , Hojas de la Planta , XilemaRESUMEN
As a kind of small molecular weight proteins, many peptides have been discovered, including peptides encoded by pri-miRNA (miPEPs). Similar as traditional phytohormone or signaling molecular, these peptides participate in numerous plant growth processes. MicroRNAs (miRNAs) play an important regulatory role in plant stress response. While the roles of miPEPs in response to abiotic stress has not been studied now. In this study, to explore whether miPEPs could contribute to low temperature (4ºC) tolerance of plants, the expression pattern of 23 different vvi-MIRs were analyzed by qRT-PCR in 'Thompson Seedless' (Vitis vinifera) plantlets under cold stress (4ºC) firstly, and vvi-MIR172b and vvi-MIR3635b which showed an elevated expression levels were selected to identify miPEPs. Through transient expression, one small open reading frame (sORF) in each of the two pri-miRNAs could increase the expression of corresponding vvi-MIR, and the amino acid sequences of sORFs were named vvi-miPEP172b and vvi-miPEP3635b, respectively. The synthetic vvi-miPEP172b and vvi-miPEP3635b were applied to the grape plantlets, and the tissue culture plantlets exhibited a higher cold tolerance compared with the control groups. These results revealed the effective roles of miPEPs in plant cold stress resistance for the first time, providing a theoretical basis for the future application of miPEPs to agricultural production.
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MicroARNs , Vitis , Regulación de la Expresión Génica de las Plantas , Vitis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Frío , Respuesta al Choque por Frío/genética , Plantas/metabolismo , Péptidos/metabolismoRESUMEN
Plasmopara viticola, the casual oomycete of grapevine downy mildew, could cause yield loss and compromise berry quantity. Previously, we have identified several PvRXLR effectors that could suppress plant immunity to promote infection and disease development. In this study, the role of effector, PvRXLR53, in plant-microbe interaction was investigated. PvRXLR53 has several orthologs in other oomycetes and contains a functional signal peptide. Expression level of PvRXLR53 was already detected upon inoculation, further induced in the early stage after P. viticola inoculation and decreased to low level in the late infection stage in grapevine (Vitis vinifera 'Cabernet Sauvignon'). PvRXLR53 is localized in both nucleus and cytoplasm. When transiently expressed in Nicotiana benthamiana, PvRXLR53 suppressed oomycete elicitor INF1-triggered programmed cell death and defense gene expression, and Phytophthora capsici-induced reactive oxygen species production (ROS) and eventually resistance to P. capsici. In summary, these findings suggest that P. viticola secretes PvRXLR53 to suppress host immunity from the very early stage of infection.
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Nicotiana/metabolismo , Vitis/metabolismo , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas/fisiología , Oomicetos/patogenicidad , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Nicotiana/microbiología , Vitis/microbiologíaRESUMEN
The compositions and contents of metabolites in the pulp tissue play critical roles in the fruit quality for table grape. In this study, the effects of root restriction (RR) on the primary and secondary metabolites of pulp tissue at five developmental stages were studied at the metabolomics level, using "Red Alexandria" grape berry (Vitis vinifera L.) as materials. The main results were as follows: 283 metabolites were annotated by using ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS); 28 and 16 primary metabolites contents were increased and decreased, and 11 and 19 secondary metabolites contents were increased and decreased, respectively, along the berry development; RR significantly decreased 12 metabolites (four amino acids and derivatives, three organic acids, four flavonoids and one other compound) contents, and improved 40 metabolites (22 amino acids and derivatives, six nucleotides, four carbohydrates, four cofactors, three cinnamic acids and one other compound) accumulation at the different developmental stages. Altogether, our study would be helpful to increase our understanding of grape berry's responses to RR stress.
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Trichome is a specialized structure differentiated during the morphogenesis of plant leaf epidermal cells. In recent years, with the continuous researches on trichome development of Arabidopsis and other plants, more and more genes related to trichome morphogenesis have been discovered, including R2R3-type MYB genes. In this study, we cloned a R2R3-type MYB family gene from grape, VvMYB114, a target gene of vvi-miR828. qRT-PCR showed that VvMYB114 mRNA accumulated during grape fruit ripening, and VvMYB114 protein had transcriptional activation activity. Heterologous overexpression of VvMYB114 in Arabidopsis reduced the number of trichome on leaves and stems. Mutating the miR828-binding site in VvMYB114 without altering amino-acid sequence had no effect on trichome development in Arabidopsis. The results showed a different role of the regulation of miR828 to VvMYB114 in Arabidopsis from in grape, which indicated the functional divergence of miRNA targeting homoeologous genes in different species played an important roles in evolution and useful trait selection.