The plant GATA family is one of the most important transcription factors involved in light-responsive development, nitrogen metabolism, phytohormone signaling, and source/sink balance. However, the ...function of the GATA gene is less known in grape (Vitis vinifera L.). In this study, we comprehensively analyzed the GATA family in grape, particularly the phylogenetic evolution, duplication patterns, conserved motifs, gene structures, cis-elements, tissue expression patterns, and predicted function of VvGATA genes in response to abiotic stress. The potential roles of VvGATA genes in berry development were also investigated. The GATA transcription factors displayed expression diversity among different grape organs and tissues, and some of them showed preferential expression in a specific tissue. Heterotrophic cultured cells were used as model systems for the functional characterization of the VvGATA gene and study of its response to light and phytohormone. Results indicated that some VvGATA genes displayed differential responses to light and phytohormones, suggesting their role in light and hormone signaling pathways. A thorough analysis of GATA transcription factors in grape (V. vinifera L.) presented the characterization and functional prediction of VvGATA genes. The data presented here lay the foundation for further functional studies of grape GATA transcription factors.
The impact of water deficit on berry quality has been extensively investigated during the last decades. Nonetheless, there is a scarcity of knowledge on the performance of varieties exposed to a ...combination of high temperatures/water stress during the growing season and under vineyard conditions. The objective of this research was to investigate the effects of two irrigation regimes, sustained deficit irrigation (SDI, 30% ET
) and regulated deficit irrigation (RDI, 15% ET
) and of two cluster positions within the canopy (east- and west-exposed sides) on berry ripening in red Aragonez (Tempranillo) grapevines. The study was undertaken for two successive years in a commercial vineyard in South Portugal, monitoring the following parameters: pre-dawn leaf water potential, berry temperature, sugars, polyphenols, abscisic acid (ABA) and related metabolites. Additionally, expression patterns for different transcripts encoding for enzymes responsible for anthocyanin and ABA biosynthesis (
β
) were analyzed. In both years anthocyanin concentration was lower in RDI at the west side (RDIW- the hottest one) from
onwards, suggesting that the most severe water stress conditions exacerbated the negative impact of high temperature on anthocyanin. The down-regulation of
expression revealed a repression of the anthocyanin synthesis in berries of RDIW, at early stages of berry ripening. At full-maturation, anthocyanin degradation products were detected, being highest at RDIW. This suggests that the negative impact of water stress and high temperature on anthocyanins results from the repression of biosynthesis at the onset of ripening and from degradation at later stages. On the other hand, berries grown under SDI displayed a higher content in phenolics than those under RDI, pointing out for the attenuation of the negative temperature effects under SDI. Irrigation regime and berry position had small effect on free-ABA concentration. However, ABA catabolism/conjugation process and ABA biosynthetic pathway were affected by water and heat stresses. This indicates the role of ABA-GE and catabolites in berry ABA homeostasis under abiotic stresses. Principal component analysis (PCA) showed that the strongest influence in berry ripening is the deficit irrigation regime, while temperature is an important variable determining the improvement or impairment of berry quality by the deficit irrigation regime. In summary, this work shows the interaction between irrigation regime and high temperature on the control of berry ripening.
While genome assembly projects have been successful in many haploid and inbred species, the assembly of noninbred or rearranged heterozygous genomes remains a major challenge. To address this ...challenge, we introduce the open-source FALCON and FALCON-Unzip algorithms (https://github.com/PacificBiosciences/FALCON/) to assemble long-read sequencing data into highly accurate, contiguous, and correctly phased diploid genomes. We generate new reference sequences for heterozygous samples including an F1 hybrid of Arabidopsis thaliana, the widely cultivated Vitis vinifera cv. Cabernet Sauvignon, and the coral fungus Clavicorona pyxidata, samples that have challenged short-read assembly approaches. The FALCON-based assemblies are substantially more contiguous and complete than alternate short- or long-read approaches. The phased diploid assembly enabled the study of haplotype structure and heterozygosities between homologous chromosomes, including the identification of widespread heterozygous structural variation within coding sequences.
SUMMARY
DNA acetylation alters the expression of responsive genes during plant development. In grapes (Vitis vinifera), however, little is known about this regulatory mechanism. In the present study, ...‘Kyoho’ grapes treated with trichostatin A (TSA, a deacetylase inhibitor) were used for transcriptome sequencing and quantitative proteomics analysis. We observed that acetylation was associated with anthocyanin accumulation and gene expression. Acetylation positively regulated phenylalanine metabolism and flavonoid biosynthesis pathways. Using omics analysis, we detected an increase in the levels of the AP2/EREBP transcription factor family after TSA treatment, indicating its association with acetylation–deacetylation dynamics in grapes. Furthermore, ethylene response factor 4 (ERF4) physically interacted with VvHDAC19, a histone deacetylase, which synergistically reduced the expression of target genes involved in anthocyanin biosynthesis owing to the binding of VvERF4 to the GCC‐box cis‐regulatory element in the VvMYB5a promoter. VvHDAC19 and VvERF4 also controlled anthocyanin biosynthesis and accumulation by regulating acetylation levels of histones H3 and H4. Therefore, alterations in histone modification can significantly regulate the expression of genes involved in anthocyanin biosynthesis and affect grape ripening.
Significance Statement
The VvERF4–HDAC19 repressor complex downregulates MYB5a by binding to the GCC‐box motif in its promoter region, subsequently reducing anthocyanin accumulation in grapes (Vitis vinifera).
Abstract
Stilbene synthase (STS) is the key enzyme leading to the biosynthesis of resveratrol. Recently we reported two R2R3-MYB transcription factor (TF) genes that regulate the stilbene ...biosynthetic pathway in grapevine: VviMYB14 and VviMYB15. These genes are strongly co-expressed with STS genes under a range of stress and developmental conditions, in agreement with the specific activation of STS promoters by these TFs. Genome-wide gene co-expression analysis using two separate transcriptome compendia based on microarray and RNA sequencing data revealed that WRKY TFs were the top TF family correlated with STS genes. On the basis of correlation frequency, four WRKY genes, namely VviWRKY03, VviWRKY24, VviWRKY43 and VviWRKY53, were further shortlisted and functionally validated. Expression analyses under both unstressed and stressed conditions, together with promoter–luciferase reporter assays, suggested different hierarchies for these TFs in the regulation of the stilbene biosynthetic pathway. In particular, VviWRKY24 seems to act as a singular effector in the activation of the VviSTS29 promoter, while VviWRKY03 acts through a combinatorial effect with VviMYB14, suggesting that these two regulators may interact at the protein level as previously reported in other species.
Grapevine (
ssp.
) is a perennial crop especially important for wine and fruit production. The species is highly polymorphic with thousands of different varieties selected by farmers and clonally ...propagated. However, it is still debated whether grapevine domestication from its wild ancestor (
ssp.
) has been a single event or rather it occurred on multiple occasions during the diffusion of its cultivation across the Mediterranean. Located in the center of the Basin, Sicily is its largest island and has served as a hotspot for all civilizations that have crossed the Mediterranean throughout history. Hundreds of unique grapevine cultivars are still cultivated in Sicily and its surrounding minor islands, though most of them are menaced by extinction. Wild grapevine is also present with isolated populations thriving along riverbanks. With the aim to evaluate the phylogenetic relationships among Sicilian varieties, and to assess the possible contribution of indigenous wild populations to the genetic makeup of cultivated grapevine, we analyzed 170 domestic cultivars and 125 wild plants, collected from 10 different populations, with 23 SSR markers. We also compared our data with published dataset from Eurasia. Results show that Sicilian wild populations are related to the cultivated Sicilian and Italian germplasm, suggesting events of introgression and/or domestication of local varieties.
Drought is one of the major abiotic stress factors that affect grape growth and yield, which in turn negatively affects the grape and wine production industry. Developing effective approaches to ...improve grapevine tolerance to drought stress is a priority for viticulture. Strigolactones, a newly discovered class of carotenoid-derived phytohormones, have been found to participate in various physiological processes. Herein, the effect of strigolactones (SLs) on grape seedlings under drought stress was investigated. Two-year-old grape seedlings (Vitis vinifera L.) were sprayed with 3 doses of rac-GR24 (1 μM, 3 μM and 5 μM), a synthesized strigolactone, and then were subjected to 7% (w/v) polyethylene glycol (PEG-6000) to simulate the drought conditions. Synthetic GR24 treated plants showed higher tolerance to drought stress with regard to lower electrolyte leakage, stomatal opening, reactive oxygen species (ROS), and higher relative water content, chlorophyll content, photosynthesis rate and malondialdehyde (MDA) content. GR24 application also decreased the levels of indoleacetic acid (IAA) and zeatin riboside (ZR), while increasing the level of abscisic acid (ABA), both in the roots and leaves under drought stress. These results suggested that foliar application of GR24 could ameliorate the adverse effects of drought due to its regulation of stomatal closure through ABA or ROS, and modulation of chlorophyll components and photosynthesis, as well as activation of the antioxidant defense capacity. Cross-talk with other hormones, especially ABA, was also suggested to be one of the important mechanism during this process. This study contributes to our current understanding of GR24-induced drought tolerance in grapevines.
•GR24 pretreatment alleviates the adverse effects of drought stress in grape seedlings.•Under drought stress, GR24 could better induce the stomatal closure.•GR24 could modulate the chlorophyll components and dampened the decrease of photosynthesis induced by drought.•Cross-talk of SLs with other hormones, especially ABA, may be one of the important mechanism in drought response.•This is the first attempt for SLs to be used in horticultural fruit tree-grape.
This paper aims a review, the main active principles obtained from the extraction of Fructus Vinifera (grapes). Vitis Vinifera (grapes) contains several active principles, including flavonoids, ...polyphenols, anthocyanins, proanthocyanidins, procyanidins, and stilbene resveratrol derivatives. In this review, we summarize the active constituents of grapes and their pharmacological effects, including antioxidants, anticancer, and antibacterials on the pathogen Streptococcus mutants and antidiabetics, in published experimental studies. In recent years, active constituents found in seeds, fruits, stems, skin, and grape pomace have been identified, and some have been studied extensively. Resveratrol (3,5,4′-trihydroxy-trans-stilben; RV), a food constituent found in grapes and wine, exerts a wide variety of pharmacological activities. The novelty of the paper refers to the properties of resveratrol, respectively to the action of cancer chemoprevention due to the inhibitory action of protein 1 associated with metastases (MTA1). This review seeks to provide a brief overview of pharmacological, toxicological and clinical studies of grapes and their active components, in particular resveratrol.