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Serendipita indica is a very promising root-associated endophytic fungus that is widely used on various plants; however, whether it affects the growth and physiological activity of an oilseed crop (Camellia oleifera) under field conditions remains unclear. In this study, we analyzed the effects of S. indica inoculation on root colonization rate, growth rate, photosynthetic parameters, mineral element concentrations and related gene expression, and sugar concentrations and expression of their transporter genes in four-year-old C. oleifera trees in the field. The results showed that the root colonization rate of C. oleifera increased from 3.37% to 9.42% following being inoculated with S. indica. Inoculation with S. indica significantly increased the plant height (46.81%), net photosynthetic rate (69.16%), nitrogen balance index (14.44%), chlorophyll index (21.08%), leaf K (7.4%), leaf Ca (13.52%), root P (17.75%), root K (12.80%), soil NH4+-N (17.78%), available K (26.66%), Olsen-P (184.30%), easily extractable glomalin-related soil protein (39.26%), and soil organic carbon (16.25%) concentrations compared to the uninoculated treatment. Inoculation with S. indica also significantly up-regulated the expression of CoHKT1;1 and CoCAX1;2 in the leaves and roots and CoPht1;1, CoPht1;2, and CoPht1;3 in the leaves. Plants inoculated with S. indica also presented significantly higher leaf glucose, fructose, and sucrose concentrations, accompanied by up-regulated expression of CoSWEET2a, CoSWEET7, CoSWEET9b, CoSWEET17a, and CoSWEET17b. These results suggest that S. indica has significant potential as a biostimulant for enhancing the growth and nutritional profile of C. oleifera, thereby contributing to sustainable oilseed production. [ABSTRACT FROM AUTHOR]

Camellia oleifera is an important oilseed forest tree, but it is unknown whether and how inoculation with arbuscular mycorrhizal fungi, as well as spraying easily extractable glomalin-related soil protein (EG), regulates the fatty acid profile in seeds of this species. This study explored how inoculation with Rhizophagus intraradices (800 g inoculum/tree) and spraying EG (2.5 L/tree, four times in total, once a week) modulated the fatty acid profile for potential nutritional qualities in the seeds of 20-year-old C. oleifera. Spraying exogenous EG significantly increased fruit transverse diameter, longitudinal diameter, fruit weight, number of seeds, and seed weight but had no significant effect on the root mycorrhizal colonization rate. Inoculation with R. intraradices had no significant effect on these fruit traits but significantly boosted the root mycorrhizal colonization rate. A total of 11 saturated fatty acids and 12 unsaturated fatty acids were detected from the seeds, with the unsaturated fatty acids consisting primarily of C18:1N-12, C18:1N-9C, and C18:2-N6. Spraying exogenous EG significantly increased the levels of major unsaturated fatty acid components such as C18:1N-12, C18:1N-9C, C18:1N-7, and C18:2N-6 by 140.6%, 59.7%, 97.6%, and 60.6%, respectively, while decreasing the level of C16:0. Inoculation with R. intraradices only decreased the levels of C16:0 and C18:0, while increased the level of C18:2N-6. Both treatments increased the percentage of unsaturated fatty acids in total fatty acids, resulting in an increase in the unsaturation index of fatty acids. In addition, inoculation with R. intraradices significantly up-regulated the expression of CoFAD2, spraying exogenous EG significantly increased the expression of CoSAD, CoFAD2, and CoFAD3, and both treatments also significantly suppressed the expression of CoFAE. These findings suggested that exogenous EG as a biostimulant, is more suitable to regulate the nutritional values of fatty acids in seeds of 20-year-old C. oleifera. [ABSTRACT FROM AUTHOR]

Plant roots can be colonized by many symbiotic fungi, whereas it is unclear whether and how symbiotic fungi including arbuscular mycorrhizal fungi and endophytic fungi promote phosphorus (P) uptake in Camellia oleifera plants. The objective of the present study was to analyze the effect of inoculation with a culturable endophytic fungus (Piriformospora indica), three arbuscular mycorrhizal fungi (Funneliformis mosseae, Diversispora versiformis, and Rhizophagus intraradices), and mixture of F. mosseae, D. versiformis and R. intraradices on plant growth, root architecture, soil Olsen-P, soil phosphatase activities, leaf and root P concentrations, and phosphate transporter gene expressions, in order to explore the potential and mechanism of these symbiotic fungi on P acquisition. All the symbiotic fungi colonized roots of C. oleifera after 16 weeks, with P. indica showing the best effect on fungal colonization. All the symbiotic fungi significantly increased acid, neutral, and total phosphatase activities in the soil, accompanied with an elevation of soil Olsen-P, of which P. indica presented the best effect. All symbiotic fungal treatments, except D. versiformis, significantly promoted plant growth, coupled with an increase in root total length, area, and volume. Symbiotic fungi almost up-regulated root CoPHO1-3 expressions as well as leaf CoPHO1-1, CoPHO1-3, and CoPHT1;4 expressions. Correlation analysis showed that P concentrations in leaves and roots were significantly positively correlated with root morphological variables (length, volume, and surface area) and soil acid, neutral and total phosphatase activities. It is concluded that symbiotic fungi, especially P. indica, played an important role in P uptake of C. oleifera plants through regulating root architecture, part plant phosphate transporter gene expressions and soil phosphatase activities. [ABSTRACT FROM AUTHOR]

Based on the interaction modes of the natural 20S proteasome inhibitors TMC-95A, we have previously discovered a dipeptide 1. To explore the SAR around compound 1, we designed and synthesized a series of dipeptides (8–38) with a fragment-based strategy. Among them, nine compounds showed significant inhibitory activities against the chymotrypsin-like activity of human 20S proteasome with IC50 values at the submicromolar level, which were comparable or even superior to the parent compound 1. Meanwhile, they displayed no significant inhibition against trypsin-like and caspase-like activities of 20S proteasome. The results suggested the feasibility to design dipeptides as novel and potent 20S proteasome inhibitors. [ABSTRACT FROM AUTHOR]

NPRL-Z-1 is a 4β-[(4″-benzamido)-amino]-4′-O-demethyl-epipodophyllotoxin derivative. Previous reports have shown that NPRL-Z-1 possesses anticancer activity. Here NPRL-Z-1 displayed cytotoxic effects against four human cancer cell lines (HCT 116, A549, ACHN, and A498) and exhibited potent activity in A498 human renal carcinoma cells, with an IC50 value of 2.38 µM via the MTT assay. We also found that NPRL-Z-1 induced cell cycle arrest in G1-phase and detected DNA double-strand breaks in A498 cells. NPRL-Z-1 induced ataxia telangiectasia-mutated (ATM) protein kinase phosphorylation at serine 1981, leading to the activation of DNA damage signaling pathways, including Chk2, histone H2AX, and p53/p21. By ICE assay, the data suggested that NPRL-Z-1 acted on and stabilized the topoisomerase II (TOP2)–DNA complex, leading to TOP2cc formation. NPRL-Z-1-induced DNA damage signaling and apoptotic death was also reversed by TOP2α or TOP2β knockdown. In addition, NPRL-Z-1 inhibited the Akt signaling pathway and induced reactive oxygen species (ROS) generation. These results demonstrated that NPRL-Z-1 appeared to be a novel TOP2 poison and ROS generator. Thus, NPRL-Z-1 may present a significant potential anticancer candidate against renal carcinoma. [ABSTRACT FROM AUTHOR]

Bilirubin (BR) aggregating at liquid/liquid interface was firstly detected by Fourier transform infrared (FTIR) imaging/spectroscopy combining with ultraviolet-visible (UV/Vis) absorption spectra. In the UV/Vis absorption spectra of BR aggregate, a new shoulder appeared at 474 nm, and BR absorption maximum underwent red shift from 450 nm to a longer wavelength at 497 nm, which indicates that BR aggregate was formed at the interface. Meanwhile, the BR molecule structure changed or conformation torsion, that is, the increase in orbit overlap or dihedral angle and the enhancement of exciton coupling. In the study of FTIR imaging/spectroscopy, the hydrogen bond-sensitive infrared bands of BR aggregate showed remarkable changes in band shift and intensity compared with those of BR powder, suggesting that the intramolecular hydrogen bonds broke out and internal structure changed. These new findings will be helpful for understanding of the BR molecular interaction, transportation, complex with serum albumin and metal ions, and the effect of BR aggregating on biomembrane and human tissues. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

GL331, a topoisomerase II inhibitor, has been found to trigger DNA damage response (DDR) to induce cell cycle arrest. However, the underlying mechanism has not yet been fully understood. This study investigated the molecular mechanism involved in the GL331-induced cell cycle arrest via DDR in human hepatocellular carcinoma HepG2 cells. As a result, GL331 could induce S arrest and up-regulate the phosphorylation of the histone H2AX variant (γ-H2AX). Ataxia telangiectasia mutated protein kinase (ATM) was activated by GL331 through its autophosphorylation at Ser1981, which led to the activation of DNA damage signaling pathways including p53/p21 and Chk2/Cdc25A cascades. The DNA damage cascades triggered by GL331 finally induced the inactivation of cyclin A/Cdk2 complexes to some extent. These phenomena could be reversed by ATM siRNA, followed by a partial disruption of S arrest. The present results suggested that the S arrest induced by GL331 via DDR was in an ATM-dependent manner to some degree. [ABSTRACT FROM PUBLISHER]

PTP1B is a negative regulator of insulin signaling pathway. This study investigated the effects of compound CCF06240, a PTP1B inhibitor, on insulin sensitivity and lipid metabolic abnormalities in vivo and in vitro, respectively. The insulin resistant IRM mouse model was induced by HFD. The responses to insulin were determined by OGTT, ITT, and hyperinsulinemic-euglycemic clamp test. The body weight and the levels of serum TC and TG were measured to estimate the lipid metabolism in vivo. Recombinant human GST-PTP1B protein was used to measure the inhibition of CCF06240 on PTP1B activity. The hepatocyte lipid accumulation was induced by high concentrations of FFA and insulin in HepG cells, and evaluated by the Oil Red O method. In IRM mice, the insulin resistance was improved; the body weight and the levels of TC and TG were also reduced by oral CCF06240 administration. In lipid accumulated model cells, CCF06240 was found to reverse the increased PTP1B activity, enhance the insulin-induced tyrosine phosphorylation in insulin signaling pathway, attenuate the FFA-insulin-induced cellular lipid accumulation, and down-regulate the expressions of genes related fatty acid synthesis. These results demonstrated that the PTP1B inhibitor, compound CCF06240, could increase insulin sensitivity through the regulation of insulin signaling pathway, and decrease FFA-insulin-induced hepatocytes lipid accumulation by reducing fatty acid syntheses. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) are well known for their important physiological implications on diversified host plants, while the information on AMF diversity and its relationship with soil properties of Camellia oleifera is yet not fully understood. In the proposed study, high-throughput sequencing of small subunit ribosomal RNA was performed to analyze the AMF diversity of the rhizosphere and endosphere of 20-year-old C. oleifera Xianglin in the field at Wuhan (China) and their relationship with soil physico-chemical properties. As high as 30.73–41.68% of the roots of C. oleifera were colonized by indigenous AMF with a spore density of 66–111 spores/10 g soil. The surface soil (0–20 cm) showed significantly higher root fungal colonization, spore density, soil hyphal length, and easily extractable glomalin-related soil protein content than the sub-surface soil (20–40 cm). Soil pH value, available K, and NO3−-N content affected the root and soil mycorrhizal development, whilst soil pH proved to be the most influential soil property governing their variability. A total of 467 OTUs associated with AMF were detected from the endosphere and rhizosphere, representing 10 genera and 138 species, of which 295 OTUs and 9 genera were jointly observed. The genus Glomus displayed maximum relative abundance (>86%) in both endosphere and rhizosphere. Scutellospora was detected in the endosphere, but absent in the rhizosphere. The endosphere recorded a relatively higher number of OTUs and alpha diversity indices (Shannon, Simpson, and PD index) of AMF than rhizosphere. Our study, hence, revealed that C. oleifera in fields was mainly colonized by Glomus, coupled with comparatively greater AMF diversity in the endosphere than in the rhizosphere, governed predominantly by soil pH, NO3−-N content, and available K content. [ABSTRACT FROM AUTHOR]

The structural stability of Zn2GeO4 was investigated by in-situ synchrotron radiation angle dispersive x-ray diffraction. The pressure-induced amorphization is observed up to 10 GPa at room temperature. The high-pressure and high-temperature sintering experiments and the Raman spectrum measurement firstly were performed to suggest that the amorphization is caused by insufficient thermal energy and tilting Zn–O–Ge and Ge–O–Ge bond angles with increasing pressure, respectively. The calculated bulk modulus of Zn2GeO4 is 117.8 GPa from the pressure-volume data. In general, insights into the mechanical behavior and structure evolution of Zn2GeO4 will shed light on the micro-mechanism of the materials variation under high pressure and high temperature. [ABSTRACT FROM AUTHOR]