Kaolin impacts on hormonal balance, polyphenolic composition and oenological parameters in red grapevine berries during ripening

BACKGROUND: Kaolin particle-film application is a well-known strategy to avoid fruit damage. However, its putative role in balancing berry ripening under a changing climate remains poorly explored. OBJECTIVE: We assessed kaolin treatment effect on several ripening berry components, hormonal balance and oenological parameters of the field-grown Touriga-Franca (TF) and Touriga–Nacional (TN) grapevine varieties at veraison (EL35) and ripening (EL38) during two growing seasons (2017 and 2018). RESULTS: Under the adverse summer conditions (two heatwave events) of 2017, kaolin application increased 211.2 %and 51.4 %the salicylic acid (SA) and abscisic acid (ABA) levels in TF berries at EL38, while no significant differences were observed in TN. Conversely, TF, and TN kaolin treated berries showed lower SA and ABA accumulation in 2018, respectively. Tartaric acid content increased about 17.2 %, and 24.2 %in TF and TN treated berries at stage EL35 in the 2017 growing season. Though kaolin treatment had no consistent effect on anthocyanins accumulation, flavonoids, ortho-diphenols and tannins increased in kaolin treated grapevines in 2017. CONCLUSIONS: This study highlights the key role of climate in triggering ripening related processes and fruit quality potential. Nevertheless, kaolin treated grapevines displayed an improved response to oxidative stress signals by increasing secondary metabolites accumulation in warm vintages. Kaolin application promoted different varietal responses, with a possible ripening delaying effect in TF, reinforcing its efficiency in alleviating severe summer stress impacts.

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Oxidative stress promotes liver cancer metastasis via a PKA-activated RNF25/ECAD/YAP circuit

10.21203/rs.3.rs-1197819/v1 ◽

2022 ◽

Author(s):

Zhao Huang ◽

Li Zhou ◽

Jiufei Duan ◽

Siyuan Qin ◽

Yu Wang ◽

...

Keyword(s):

Oxidative Stress ◽

Cancer Metastasis ◽

Anoikis Resistance ◽

Antioxidant Genes ◽

Redox Sensor ◽

Stress Signals ◽

Hcc Cells

Abstract Loss of E-cadherin (ECAD), often caused by epigenetic inactivation, is closely associated with tumor metastasis. However, how ECAD is regulated in response to oxidative stress during tumorigenesis is largely unknown. Here we identify RNF25 as a new E3 ligase of ECAD, whose activation by oxidative stress leads to ECAD protein degradation in hepatocellular carcinoma (HCC). Loss of ECAD activates YAP, which in turn promotes the transcription of RNF25, thus forming a positive feedback loop to sustain the ECAD downregulation. YAP activation mitigates oxidative stress in detached HCC cells by upregulating antioxidant genes, protecting detached HCC cells from ferroptosis, resulting in anoikis resistance. Mechanistically, we found that protein kinase A (PKA) senses oxidative stress by redox modification in its β catalytic subunit (PRKACB) at Cys200 and Cys344, which increases its kinase activity towards RNF25 phosphorylation at Ser450, facilitating RNF25-mediated degradation of ECAD. Moreover, RNF25 expression is associated with HCC metastasis and depletion of RNF25 is sufficient to diminish HCC invasion and metastasis in vitro and in vivo. Together, these results identify a dual role of RNF25 as a critical regulator of ECAD protein turnover, promoting both anoikis resistance and metastasis, and PKA is a necessary redox sensor to enable this process. Our study provides mechanistic insight into how tumor cells sense oxidative stress signals to spread while escaping cell death.

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Optimising grapevine summer stress responses and hormonal balance by applying kaolin in two Portuguese Demarcated Regions

OENO One ◽

10.20870/oeno-one.2021.55.1.4502 ◽

2021 ◽

Vol 55 (1) ◽

pp. 207-222

Author(s):

Sara Bernardo ◽

Lia-Tânia Dinis ◽

Ana Luzio ◽

Nelson Machado ◽

Alexandre Gonçalves ◽

...

Keyword(s):

Stress Responses ◽

Environmental Conditions ◽

Sugar Content ◽

Soluble Sugar ◽

Carbon Assimilation ◽

Mitigation Strategies ◽

Growing Seasons ◽

Hormonal Balance ◽

Summer Stress ◽

Grapevine Leaves

In Mediterranean-like climate areas, field-grown grapevines are typically exposed to severe environmental conditions during the summer season, which can negatively impact the sustainability of viticulture. Despite the short-term mitigation strategies available nowadays to cope with climate change, little is known regarding their effectiveness in different demarcated winegrowing regions with differing climate features. Hence, we applied a kaolin suspension (5 %) to Touriga-Franca (TF) and Touriga-Nacional (TN) grapevine varieties located in two Portuguese demarcated regions (Alentejo and Douro) with different mesoclimates to study its effect on the physiological performance, hormonal balance and ABA-related grapevine leaf gene expression during the 2017 and 2018 growing seasons. Data show that 2017 was warmer than 2018 due to the occurrence of two heatwaves in both locations, highlighting the protective effect of kaolin application under severe environmental conditions. In the first study year, at midday, kaolin enhanced water use efficiency (23 % in Douro and 13 % in Alentejo), carbon assimilation rates (PN; 72 % in Douro and 25 % in Alentejo), and the soluble sugar content of grapevine leaves, while decreasing the accumulation of plant growth regulators (ABA, IAA, and SA) during the ripening stage. The results show an up-regulation of ABA biosynthesis-related genes (VvNCED) in TF treated vines from the Douro vineyard mainly in 2017, suggesting an increased stress response under severe summer conditions. Additionally, kaolin triggered the expression of ABA-responsive genes (VvHVA22a and VvSnRK2.6) mainly in TF, indicating different varietal responses to kaolin application under fluctuating periods of summer stress.

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Melatonin Modulation of Sirtuin-1 Attenuates Liver Injury in a Hypercholesterolemic Mouse Model

BioMed Research International ◽

10.1155/2018/7968452 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 11

Author(s):

Francesca Bonomini ◽

Gaia Favero ◽

Luigi Fabrizio Rodella ◽

Mohammed H. Moghadasian ◽

Rita Rezzani

Keyword(s):

Oxidative Stress ◽

Biochemical Markers ◽

Antioxidant Properties ◽

Sirtuin 1 ◽

Oral Supplementation ◽

Stress Markers ◽

Serum Biochemical ◽

Stress Signals

Hypercholesterolemia increases and exacerbates stress signals leading also to liver damage (LD) and failure. Sirtuin1 (SIRT1) is involved in lifespan extension and it plays an essential role in hepatic lipid metabolism. However, its involvement in liver hypercholesterolemic damage is not yet completely defined. This in vivo study evaluated the role of SIRT1 in the hypercholesterolemic-related LD and, then, investigated how oral supplementation of melatonin, pleiotropic indoleamine, may be protective. Control mice and apolipoprotein E-deficient mice (ApoE−/−) of 6 and 15 weeks of age were treated or not treated with melatonin at the dose of 10 mg/kg/day for 9 weeks. In this study, we evaluated serum biochemical markers, liver SIRT1 expression, and oxidative stress markers. We observed that hypercholesterolemia increased significantly serum cholesterol and triglycerides, reduced significantly liver SIRT1, and, in turn, induced hepatic oxidative stress in untreated ApoE−/− mice with respect to control mice. Interestingly, melatonin treatment improved serum biochemical markers and hepatic morphological impairment and inhibited oxidative stress through its antioxidant properties and also by SIRT1 upregulation. In summary, melatonin oral supplementation may represent a new protective approach to block hypercholesterolemic liver alterations involving also a SIRT1-dependent mechanism.

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Epiphytic Microbiome of Grapes Berries Varies Between Phenological Timepoints, Growing Seasons and Regions

10.1101/2019.12.20.884502 ◽

2019 ◽

Author(s):

Megan E. Hall ◽

Isabelle O’Bryon ◽

Wayne F. Wilcox ◽

Michael V. Osier ◽

Lance Cadle-Davidson

Keyword(s):

New York ◽

Growing Season ◽

Phenological Stage ◽

Phenological Stages ◽

Growing Seasons ◽

Single Region ◽

Finger Lakes ◽

Primary Focus ◽

One Year

AbstractExtensive research into the microbial ecology of grapes near harvest, with a primary focus on yeasts, has improved our understanding of some components of variation that influence grapevine terroir. Metagenomic tools enable a broader exploration of the plant microbiome and components of variability due to such factors as year, location, management, and phenological stage. In 2014, to characterize the microbial changes of the grape surface over the course of the growing season in the Finger Lakes region of New York, we examined the epiphytic microbiome of grapes at five key phenological stages: pea-sized, bunch closure, Veraison, 15 Brix and harvest. This experiment was repeated in two subsequent years in the Finger Lakes, New York in 2015, and in Tasmania, Australia in 2016, to examine variability of regional terroir. We found significant shifts in taxa presence and relative taxa abundance between phenological timepoints, and determined that the epiphytic microbiome differed significantly not just between regions but also within a single region from one year to the next. These findings call into question the role of the phytobiome in the expression of terroir, as the phytobiome is dynamically responding to its environment, within and between years and locations. On the berry surface in particular, these dynamics are complicated by weather and management. Understanding that the grape surface microbiome is consistently changing may influence how we manage the berry epiphytic microbiome, potentially affecting disease management and vinification decisions.

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Differential Response of Grapevine to Infection with ‘Candidatus Phytoplasma solani’ in Early and Late Growing Season Through Complex Regulation of mRNA and Small RNA Transcriptomes

International Journal of Molecular Sciences ◽

10.3390/ijms22073531 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3531

Author(s):

Marina Dermastia ◽

Blaž Škrlj ◽

Rebeka Strah ◽

Barbara Anžič ◽

Špela Tomaž ◽

...

Keyword(s):

Small Rnas ◽

Interaction Network ◽

Growing Season ◽

Transcriptional Level ◽

Rna Seq ◽

Bois Noir ◽

Growing Seasons ◽

New Genes ◽

Causal Pathogen

Bois noir is the most widespread phytoplasma grapevine disease in Europe. It is associated with ‘Candidatus Phytoplasma solani’, but molecular interactions between the causal pathogen and its host plant are not well understood. In this work, we combined the analysis of high-throughput RNA-Seq and sRNA-Seq data with interaction network analysis for finding new cross-talks among pathways involved in infection of grapevine cv. Zweigelt with ‘Ca. P. solani’ in early and late growing seasons. While the early growing season was very dynamic at the transcriptional level in asymptomatic grapevines, the regulation at the level of small RNAs was more pronounced later in the season when symptoms developed in infected grapevines. Most differentially expressed small RNAs were associated with biotic stress. Our study also exposes the less-studied role of hormones in disease development and shows that hormonal balance was already perturbed before symptoms development in infected grapevines. Analysis at the level of communities of genes and mRNA-microRNA interaction networks revealed several new genes (e.g., expansins and cryptdin) that have not been associated with phytoplasma pathogenicity previously. These novel actors may present a new reference framework for research and diagnostics of phytoplasma diseases of grapevine.

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