The grapevine miR827a regulates the synthesis of stilbenes by targeting VqMYB14 and gives rise to susceptibility in plant immunity.

Grapevine (Vitis vinifera L.) is an economically important fruit crop cultivated worldwide. In China, grapevine cultivation is very extensive, and a few Vitis grapes have excellent pathogen and stress resistance, but the molecular mechanisms underlying the grapevine response to stress remain unclear. In this study, a microRNA (miRNA; miR827a), which negatively regulates its target gene VqMYB14, a key regulatory role in the synthesis of stilbenes, was identified in Vitis quinquangularis (V. quinquangularis) using transcriptome sequencing. Using overexpression and silencing approaches, we found that miR827a regulates the synthesis of stilbenes by targeting VqMYB14. We used flagellin N-terminal 22-amino-acid peptide (flg22), the representative elicitor in plant basal immunity, as the elicitor to verify whether miR827a is involved in the basal immunity of V. quinquangularis. Furthermore, the promoter activity of miR827a was alleviated in transgenic grape protoplasts and Arabidopsis thaliana following treatment with flg22 and Pseudomonas syringae pv. Tomato DC3000 (Pst DC3000), respectively. In addition, yeast one-hybrid and dual luciferase reporter assay revealed that the ethylene transcription factor VqERF057 acted as a key regulator in the inhibition of miR827a transcription. These results will contribute to the understanding of the biological functions of miR827a in grapevine and clarify the molecular mechanism of the interaction between miR827a and VqMYB14.

Spinal microglial activation promotes perioperative social defeat stress-induced prolonged postoperative pain in a sex-dependent manner.

Prolonged postsurgical pain, which is associated with multiple risk factors in the perioperative stage, is a common medical and social problem worldwide. Suitable animal models should be established to elucidate the mechanisms underlying the perioperative prolonged postsurgical pain. In this study, standard and modified social defeat stress mice models, including chronic social defeat stress (CSDS), chronic nondiscriminatory social defeat stress (CNSDS) and vicarious social defeat stress (VSDS), were applied to explore the effect of perioperative social defeat stress on postsurgical pain in male and female mice. Our results showed that exposure to preoperative CSDS could induce prolonged postsurgical pain in defeated mice regardless of susceptibility or resilience differentiated by the social interaction test. Similar prolongation of incision-induced mechanical hypersensitivity was also observed in both sexes upon exposing to CNSDS or VSDS in the preoperative period. Moreover, we found that using the modified CNSDS or VSDS models at different recovery stages after surgery could still promote abnormal pain without sex differences. Further studies revealed the key role of spinal microglial activation in the stress-induced transition from acute to prolonged postoperative pain in male but not female mice. Together, these data indicate that perioperative social defeat stress is a vital risk factor for developing prolonged postoperative pain in both sexes, but the promotion of stress-induced prolonged postoperative pain by spinal microglial activation is sexually dimorphic in mice.

Acrocalyenes A and B, Two New Diterpenoids from Sinomenium acutum Associated Fungus Acrocalymma sp.

We identified two new diterpenoidal acrocalyenes A (1) and B (2) through chemical investigation on Acrocalymma sp., a plant-associated fungus from the tender stem isolates of Sinomenium acutum collected from the Qinling Mountains, along with seven already-recognized compounds (3-9). The HR-ESI-TOF-MS and 1D/2D NMR data were utilized for structural elucidation of these compounds, and the single-crystal X-ray diffraction was employed for absolute configuration clarification of the novel acrocalyenes 1 and 2. Bioassays revealed that the cytotoxicities of compounds 2, 4, 6, 7, and 8 against three human carcinoma cells (RKO, HeLa and HCC-1806) were moderate to strong, with IC50 between 6.70-38.82 µM. These isolates were also evaluated for their fungal resistant potentials against Botrytis cinerea, Fusarium culmorum and Fusarium solani, in which 3 displayed significant inhibitory effects on all three phytopathogenic fungi, showing respective MIC of 50, 25 and 25 µM.

Transcriptome and metabolome analysis of stress tolerance to aluminium in Vitis quinquangularis.

MAIN CONCLUSION: Transcriptional and metabolic regulation of aluminium tolerance of Chinese wild Vitis quinquangularis after Al treatment for 12 h: genes and pathways related to stress resistance are activated to cope with Al stress. The phytotoxicity of aluminium (Al) has become a major issue in inhibiting plant growth in acidic soils. Chinese wild Vitis species have excellent stress resistance. In this study, to explore the mechanism underlying Al tolerance in Chinese wild Vitis quinquangularis, we conducted a transcriptome analysis to understand the changes in gene expression and pathways in V. quinquangularis leaves after Al treatment for 12 h (Al_12 h). Compared with the control (CK) treatment, 2266 upregulated differentially expressed genes (DEGs) and 2943 downregulated DEGs were identified after Al treatment. We analysed the top 60 upregulated DEGs and found that these genes were related mostly to cell wall organization or biogenesis, transition metal ion binding, etc. Another analysis of all the upregulated DEGs showed that genes related to the ABC transport pathway, salicylic acid (SA), jasmonic acid (JA) and abscisic acid (ABA) hormone signalling pathway were expressed. Transcriptome and metabolome analysis revealed that genes and metabolites (phenylalanine, cinnamate and quercetin) related to the phenylalanine metabolic pathway were expressed. In summary, the results provide a new contribution to a better understanding of the metabolic changes that occur in grapes after Al stress as well as to research on improving the resistance of grape cultivars.

Morphology, molecular characterization, and virulence of Beauveria pseudobassiana isolated from different hosts.

Beauveria pseudobassiana has great potential for use in the management of various insect pests. In the present study, we aimed to explore the the virulence of B. pseudobassiana isolated from a diversity of hosts to Bombyx mori and Tenebrio molitor larvae. To this end, 15B. pseudobassiana isolates from 10 different geographical locations were identified based on morphological characteristics and molecular data. The phylogenetic positions of the isolates were evaluated according to morphological features and phylogenetic inferences based on six loci (nrSSU, nrLSU, TEF, RPB1, RPB2 and Bloc). In addition to growth in soil, the B. pseudobassiana isolates in our study were isolated from a wide host range that extended to 5 orders, 11 families, and 14 species. Moreover, anamorphically typified B. pseudobassiana was grown for the first time from teleomorph stromata. Pathogenicity of the B. pseudobassiana isolates from the different hosts was determined with two bioassays using B. mori and T. molitor larvae. The results indicated that mortality of B. mori caused by the lepidopteran isolates was significantly higher than that of isolates from other hosts, and virulence of the coleopteran isolates to T. molitor was significantly higher than that of isolates from other hosts. The host specificity of B. pseudobassiana should be studied in more detail before future consideration of isolates for use in biological control of pests.

CTRP12 Ameliorated Lipopolysaccharide-Induced Cardiomyocyte Injury.

C1q/tumor necrosis factor (TNF)-related protein 12 (CTRP12) is a secretory protein that participates in the regulation of glucose and lipid metabolism in obesity and diabetes. Its role in cardiovascular disease, particularly sepsis-induced cardiac injury, is unclear. Here, we stimulated cardiomyocytes with lipopolysaccharide (LPS) to establish an in vitro cardiomyocyte injury model and CTRP12 was overexpressed with an adenovirus delivery system. Overexpression of CTRP12 reduced the transcription and release of pro-inflammatory cytokines from LPS-stimulated cardiomyocytes, including TNFα, interleukin-1 (IL-1), and IL-6. Reactive oxygen species (ROS) level increased and the oxidation/redox system was disturbed in LPS-stimulated cardiomyocytes, as evident from the decrease in superoxide dismutase activity and an increase in reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and malondialdehyde level. CTRP12 overexpression decreased the increasing level of ROS and ameliorated the unbalance in the oxidation/redox system in LPS-stimulated cardiomyocytes. The viability of cardiomyocytes decreased after LPS stimulation, and the cells underwent apoptosis. CTRP12-overexpressing cardiomyocytes showed a decrease in the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL)-positive cells, and the ratio of B cell lymphoma (Bcl)-1/Bax in these cells was recovered. In comparison with the control group, LPS-stimulated cardiomyocytes showed reduced expression of nuclear factor E2-related factor 2 (NRF2), while CTRP12-overexpressing cardiomyocytes showed elevated NRF2 expression. Small-interfering RNA-mediated silencing of NRF2 expression in cardiomyocytes resulted in the inhibition of the protective effects of CTRP12. Thus, CTRP12 ameliorated injury in LPS-stimulated cardiomyocytes in an NRF2-dependent manner.

The Effect of Transcription Factor MYB14 on Defense Mechanisms in Vitis quinquangularis-Pingyi.

In the current study, we identified a transcription factor, MYB14, from Chinese wild grape, Vitis quinquangularis-Pingyi (V. quinquangularis-PY), which could enhance the main stilbene contents and expression of stilbene biosynthesis genes (StSy/RS) by overexpression of VqMYB14. The promoter of VqMYB14 (pVqMYB14) was shown to be induced as part of both basal immunity (also called pathogen-associated molecular pattern (PAMP)-triggered immunity, PTI) and effector-triggered immunity (ETI), triggered by the elicitors flg22 and harpin, respectively. This was demonstrated by expression of pVqMYB14 in Nicotiana benthamiana and Vitis. We identified sequence differences, notably an 11 bp segment in pVqMYB14 that is important for the PTI/ETI, and particularly for the harpin-induced ETI response. In addition, we showed that activation of the MYB14 promoter correlates with differences in the expression of MYB14 and stilbene pattern induced by flg22 and harpin. An experimental model of upstream signaling in V. quinquangularis-PY is presented, where early defense responses triggered by flg22 and harpin partially overlap, but where the timing and levels differ. This translates into a qualitative difference with respect to patterns of stilbene accumulation.

The transcription factor MYB15 is essential for basal immunity (PTI) in Chinese wild grape.

MAIN CONCLUSION: MYB15 promoter of Vitis quinquangularis has potential as a target for disease resistance breeding, and its involvement in PTI is associated with a range of defense mechanisms. China is a center of origin for Vitis and is home to diverse wild Vitis genotypes, some of which show superior pathogen resistance, although the underlying molecular basis for this has not yet been elucidated. In the current study, we identified a transcription factor, MYB15, from the Chinese wild grape, Vitis quinquangularis, whose promoter region (pVqMYB15) was shown to be induced by basal immunity (also called PAMP-triggered immunity, PTI) triggered by flg22, following heterologous expression in Nicotiana benthamiana and homologous expression in grapevine. By analyzing the promoter structure and activity, we identified a unique 283 bp sequence that plays a key role in the activation of basal immunity. In addition, we showed that activation of the MYB15 promoter correlates with differences in the expression of MYB15 and RESVERATROL SYNTHASE (RS) induced by the flg22 elicitor. We further tested whether the MYB15 induction triggered by flg22 was consistent with MYB15 and RS expression following inoculation with Plasmopara viticola in grape (V. quinquangularis and Vitis vinifera) leaves. Mapping upstream signals, we found that calcium influx, an RboH-dependent oxidative burst, an MAPK cascade, and jasmonate and salicylic acid co-contributed to flg22-triggered pVqMYB15 activation. Our data suggest that the MYB15 promoter has potential as a target for disease resistance breeding, and its involvement in PTI is associated with a range of defense mechanisms.

Novel dealloying-fabricated NiCo2S4 nanoparticles with excellent cycling performance for supercapacitors.

In this work, NiCo2S4 nanoparticles for supercapacitors are successfully synthesized with a top-down strategy, using a novel dealloying method with an ion exchange reaction. The surface morphology and x-ray diffraction investigations demonstrated that NiCo2S4 nanoparticles are interconnected by ligaments of the synthesized sample. The dealloyed NiCo2S4 shows an enhanced electrochemical performance of about 1132.5 F g-1 at 0.5 A g-1; kinetic analysis implies a surface-controlled contribution from NiCo2S4 (53.86% capacitive contributions). Notably, the NiCo2S4//AC (active carbon) device displays a comparatively high energy density (22.83 Wh kg-1), maximum power density (1327.1 W kg-1) and superior cycling performance (capacitance retention of 108% after 30 000 cycles).

A specific allele of MYB14 in grapevine correlates with high stilbene inducibility triggered by Al3+ and UV-C radiation.

KEY MESSAGE: The structural differences of MYB14 promoter in two grapevine genotypes affect the expression of MYB14 and stilbene synthesis in response to Al3+ and UV-C radiation. Grapevines provide an important fruit crop worldwide, but production is often limited by pathogen infection. Stilbenes, a class of secondary metabolite, represent phytoalexins that contribute to defence against pathogens in many plants, including grapevine. It is known that the transcription factors MYB14 and MYB15 are required for the activation of the promoters of resveratrol synthase to regulate stilbene biosynthesis. In the current study, we observed that stilbene levels were more highly induced by Al3+ and UV-C radiation treatments in the cultivar Vitis labrusca 'Concord' than in the cultivar V. vinifera 'Cabernet Sauvignon'. We investigated whether genetic/structural variations in the MYB14 and MYB15 promoters between these two representative genotypes are responsible for the differences in stilbene accumulation. Significant differences in the structure and activity of the promoter of MYB14, but not MYB15 were identified between the two genotypes, following heterologous expression in Nicotiana benthamiana system and treatments with Al3+ and UV-C. Hydrogen peroxide (H2O2) was detected in Concord soon after the stress treatments, but after diphenyleneiodonium chloride pre-treatment, the expressing level of VlMYB14, the promoter activity of VlMYB14 and the accumulation of stilbenes was significantly reduced. A model is presented where the induction of MYB14 contributes to stilbene accumulation in Concord following Al3+ and UV-C treatments involving reactive oxygen species (ROS) production as an early signal.

Sinopestalotiollides A-D, cytotoxic diphenyl ether derivatives from plant endophytic fungus Pestalotiopsis palmarum.

Four new diphenyl ether derivatives, sinopestalotiollides A-D (1-4), one new natural α-pyrone product (11), as well as twelve known compounds (5-1 7), were obtained from the ethyl acetate extract of the endophytic fungus Pestalotiopsis palmarum isolated from the leaves of medicinal plant Sinomenium acutum (Thunb.) Rehd et Wils. The structures were elucidated by HR-ESI-MS and NMR spectrometry data. Bioassay experiments revealed that compounds 1-4 and 11 exhibited strong to weak cytotoxicities against three human tumor cell lines Hela, HCT116 and A549.

Monolithic Au/CeO2 nanorod framework catalyst prepared by dealloying for low-temperature CO oxidation.

Monolithic Au/CeO2 nanorod frameworks (NFs) with porous structure were prepared by dealloying melt-spun Al89.7Ce10Au0.3 ribbons. After calcination in O2, a 3D Au/CeO2 NF catalyst with large surface area was obtained and used for low-temperature CO oxidation. The small Au clusters/nanoparticles (NPs) were in situ supported and highly dispersed on the nanorod surface, creating many nanoscale contact interfaces. XPS results demonstrated that high-concentration oxygen vacancy and Au δ+/Au0 co-existed in the calcined sample. The Au/CeO2 nanorod catalyst calcined at 400 °C exhibited much higher catalytic activity for CO oxidation compared with the dealloyed sample and bare CeO2 nanorods. Moreover, its complete reaction temperature was as low as 91 °C. The designed Au/CeO2 NF catalyst not only possessed extreme sintering resistance but also exhibited high performance owing to the enhanced interaction between the Au clusters/NPs and CeO2 nanorod during calcination.

Constituents with potent α-glucosidase inhibitory activity from Pueraria lobata (Willd.) ohwi.

One new flavone hydrate named lobatflavate (1), one new chromone named lobatchrosin (2), and one new isoflavone named 3S,4R-tuberosin (3), along with four known isoflavone analogues (4-7), were isolated from the traditional Chinese medicinal plant of Pueraria lobata (Willd.) ohwi. Their structures were elucidated by extensive spectroscopic methods of IR, UV, HR-ESI-MS, 1D and 2D NMR. The absolute configuration of 3 was determined by CD spectrum associated with TD-DFT calculation analysis. All compounds except for 2 were assayed the inhibitory activity against α-glucosidase. Every tested compound was proved to be more active than positive control of acarbose. Of which 1 and 4 showed significant activity with IC50 value of 1.79µM and 23.01µM (IC50 of acarbose was 1998.79µM). Enzyme kinetic experiments revealed that 1 was irreversible whereas 4 was reversible and non-competitive α-glucosidase inhibitors. Moreover, structure-activity relationship was discussed and the docking studies of 1, 3 and 4 were also carried out.

A stilbene synthase allele from a Chinese wild grapevine confers resistance to powdery mildew by recruiting salicylic acid signalling for efficient defence.

Stilbenes are central phytoalexins in Vitis, and induction of the key enzyme stilbene synthase (STS) is pivotal for disease resistance. Here, we address the potential for breeding resistance using an STS allele isolated from Chinese wild grapevine Vitis pseudoreticulata (VpSTS) by comparison with its homologue from Vitis vinifera cv. 'Carigane' (VvSTS). Although the coding regions of both alleles are very similar (>99% identity on the amino acid level), the promoter regions are significantly different. By expression in Arabidopsis as a heterologous system, we show that the allele from the wild Chinese grapevine can confer accumulation of stilbenes and resistance against the powdery mildew Golovinomyces cichoracearum, whereas the allele from the vinifera cultivar cannot. To dissect the upstream signalling driving the activation of this promoter, we used a dual-luciferase reporter system in a grapevine cell culture. We show elevated responsiveness of the promoter from the wild grape to salicylic acid (SA) and to the pathogen-associated molecular pattern (PAMP) flg22, equal induction of both alleles by jasmonic acid (JA), and a lack of response to the cell death-inducing elicitor Harpin. This elevated SA response of the VpSTS promoter depends on calcium influx, oxidative burst by RboH, mitogen-activated protein kinase (MAPK) signalling, and JA synthesis. We integrate the data in the context of a model where the resistance of V. pseudoreticulata is linked to a more efficient recruitment of SA signalling for phytoalexin synthesis.

An ancestral allele of grapevine transcription factor MYB14 promotes plant defence.

Stilbene synthase is a key enzyme for the production of the phytoalexin resveratrol. Some clones of Vitis sylvestris, a wild European grapevine species which is almost extinct, have been shown to accumulate more resveratrol in response to different forms of stress. In the current study, we asked whether the induction of stilbene synthase transcripts in Hoe29, one of the V. sylvestris clones with elevated stilbene inducibility, might result from the elevated induction of the transcription factor MYB14. The MYB14 promoter of Hoe29 and of Ke83 (a second stilbene-inducible genotype) harboured distinct regions and were applied to a promoter-reporter system. We show that stilbene synthase inducibility correlates with differences in the induction of MYB14 transcripts for these two genotypes. Both alleles were induced by UV in a promoter-reporter assay, but only the MYB14 promoter from Hoe29 was induced by flg22, consistent with the stilbene synthase expression of the donor genotypes, where both respond to UV but only Hoe29 is responsive to Plasmopara viticola during defence. We mapped upstream signals and found that a RboH-dependent oxidative burst, calcium influx, a MAPK cascade, and jasmonate activated the MYB14 promoter, whereas salicylic acid was ineffective. Our data suggest that the Hoe29 allele of the MYB14 promoter has potential as a candidate target for resistance breeding.

[Application of (18)F-fluorodeoxyglucose Metabolic Imaging in Diagnosis and Treatment of Cervical Cancer].

The main purpose of this study is to evaluate the clinical value of 18F-fluorodeoxyglucose（18 F-FDG）metabolism imaging in accurate staging and prognosis prediction before treatment of cervical cancer.18F-FDG single photon emission computed tomography（SPECT/CT）was performed before treatment on 27 patients with cervical cancer and was analyzed retrospectively.All the images were analyzed by image fusion software.Meanwhile,primary tumor size and T/B,lymph nodes size and T/B were measured by software.Comparison of the relationship between primary tumor T/B of cervix and clinic pathological factors was performed using SPSS17.0.The diagnosis was established according to pathology results of surgery or/and multi-modalities of imaging and clinical following up.The results showed that the primary tumor T/B value of cervix was 5.9（3.2）.With the increased clinical stage,T/B of primary tumor value was significantly increased（P<0.05）.The T/B value in patients≥Ⅱa stage was significantly higher than those of≤Ⅰb stage.There were no significant correlations between T/B value and primary tumor size,lymph-node metastasis,and histological type（P>0.05）.Thirteen lymph nodes were detected by 18F-FDG imaging in 27 patients with cervical cancer.For diagnosing lymph nodes metastasis,the sensitivity,specificity,accuracy,positive and negative predictive value by 18F-FDG imaging were 75.0%,78.9%,77.8%,60.0% and 88.2%,respectively.The T/B value of all lymph nodes was 6.3（3.5）,in which T/B value of distant metastasis was significantly higher than that of the pelvic metastasis（P<0.05）.There were no significant correlations between T/B value and the size of lymph nodes（P>0.05）.Uterine body uptaking FDG were discovered in 17 patients and 15 cases were then pathologically proved.Two of 15 cases were cancerous invasion of uterine body,and the other 13 cases were physiological changes of endometrial,and the T/B value of the former was significantly higher than that of the latter（P<0.05）.There were positive correlation between invasion of uterine body and lymph nodes metastasis（P<0.05）.In conclusion,18F-FDG imaging has an obvious value for the diagnosis of outside pelvic and distant lymph node metastasis,uterine body infiltrated,and accurate staging.Primary focal T/B value of cervical cancer associates with the clinical stage,which can reflect the risk of patients,and were useful to preliminarily predict the prognosis of cervical cancer.

Genetic diversity of stilbene metabolism in Vitis sylvestris.

Stilbenes, as important secondary metabolites of grapevine, represent central phytoalexins and therefore constitute an important element of basal immunity. In this study, potential genetic variation in Vitis vinifera ssp. sylvestris, the ancestor of cultivated grapevine, was sought with respect to their output of stilbenes and potential use for resistance breeding. Considerable variation in stilbene inducibility was identified in V. vinifera ssp. sylvestris. Genotypic differences in abundance and profiles of stilbenes that are induced in response to a UV-C pulse are shown. Two clusters of stilbene 'chemovars' emerged: one cluster showed quick and strong accumulation of stilbenes, almost exclusively in the form of non-glycosylated resveratrol and viniferin, while the second cluster accumulated fewer stilbenes and relatively high proportions of piceatannol and the glycosylated piceid. For all 86 genotypes, a time dependence of the stilbene pattern was observed: piceid, resveratrol, and piceatannol accumulated earlier, whereas the viniferins were found later. It was further observed that the genotypic differences in stilbene accumulation were preceded by differential accumulation of the transcripts for chalcone synthase (CHS) and stilbene-related genes: phenylalanine ammonium lyase (PAL), stilbene synthase (StSy), and resveratrol synthase (RS). A screen of the population with respect to susceptibility to downy mildew of grapevine (Plasmopara viticola) revealed considerable variability. The subpopulation of genotypes with high stilbene inducibility was significantly less susceptible as compared with low-stilbene genotypes, and for representative genotypes it could be shown that the inducibility of stilbene synthase by UV correlated with the inducibility by the pathogen.

Upregulation of SCC-S2 in immune cells and tumor tissues of papillary thyroid carcinoma.

Studies have shown that SCC-S2 can be detected in cancer cells, but its relation with thyroid cancer remains uncertain. In the current study, we investigated SCC-S2 expression in thyroid cancer from the immune cell perspective and tumor tissue perspective. Levels of SCC-S2 in CD4+ T cells, CD8+ T cells, monocytes, natural killer (NK) T cells, tumor tissues, and adjacent noncancerous thyroid tissues were tested by real-time reverse transcription PCR and Western blot. Results revealed that mRNA and protein levels of SCC-S2 were significantly increased in peripheral CD4+ (mRNA, 1.90-fold; protein, 1.55-fold) and CD8+ T cells (mRNA, 2.37-fold; protein, 1.72-fold) but not monocytes and NKT cells in patients than in healthy donors. Further elevated mRNA level but not protein expression was observed in tumor-infiltrating CD4+ T cells, whereas both mRNA level and protein expression were further increased in tumor-infiltrating CD8+ T cells. Also, mRNA and protein levels of SCC-S2 in thyroid tissues were significantly elevated than those in adjacent noncancerous thyroid tissues. Moreover, patients with cervical lymph node metastasis presented clearly higher mRNA and protein expression of SCC-S2 compared to those without cervical lymph node metastasis (p < 0.05). These results suggest that SCC-S2 may play roles in affecting both immune cells and tumor cells in the thyroid and may indicate a novel pathway for understanding the pathogenesis of the disease.

Pyrite cinder as a cost-effective heterogeneous catalyst in heterogeneous Fenton reaction: decomposition of H(2)O(2) and degradation of Acid Red B.

Pyrite cinder (PyC) was employed as a heterogeneous Fenton-like catalyst, and its catalytic activity was evaluated in view of the effects of catalyst dosage, pH and leaching metal ions. PyC showed significant reactivity, and the pseudo-first-order kinetic rate constant for decomposition of H(2)O(2) and degradation of Acid Red B (ARB) were 3.4 and 14.89 (10⁻³ min⁻¹) respectively when pH = 5. When 20 g/L PyC was added into 10 mM H(2)O(2) solution in neutral pH, H(2)O(2) could be completely degraded within 4 h, and more than 90% ARB was removed. Leaching metal ions from PyC were found to have little effect on decomposition of H(2)O(2) or on degradation of ARB. PyC still had high catalytic activity after five successive runs. The decomposition mechanism of H(2)O(2) was analyzed and the Haber-Weiss mechanism was employed in this paper. The electron spin resonance image showed •OH was produced and increased between 3 and 5 min in the PyC catalyzing H(2)O(2) reaction, which demonstrated that PyC had a durable ability to produce •OH.

VqNAC44 enhances stilbene synthesis and disease resistance in Chinese wild grape by interacting with VqMYB15.

As significant phytoalexins, stilbene compounds can improve the stress resistance of grapes under biotic and abiotic stress conditions and have biological effects such as antitumour, antioxidant, immune regulation and cardiovascular protection activities in humans. RESVERATROL SYNTHASE (RS), also known as STILBENE SYNTHASE (STS), is the critical enzyme regulating stilbene synthesis and has been identified in a few plant species. However, the regulatory mechanisms of stilbene synthesis are uncertain. In this study, an NAC family transcription factor from Vitis quinquangularis, named VqNAC44, was characterized as an indirect regulator of stilbene synthesis. It is worth noting that VqNAC44 did not bind to the STS promoter nor did it interact with the STS protein but interacted with the MYB transcription factor VqMYB15. This interaction between VqMYB15 and VqNAC44 was validated by a yeast two-hybrid assay and bimolecular fluorescence complementation. Overexpressing VqNAC44 in Arabidopsis thaliana significantly increased its tolerance to biotic and abiotic stresses. Transient overexpression of VqNAC44 and VqMYB15 in grape leaves resulted in increased expression of the STS gene and increased production of stilbene compounds. The experimental results confirmed that VqNAC44 regulated stilbene synthesis by interacting with VqMYB15, thereby enhancing the plant stress resistance.