Comprehensive analysis revealed that titanium dioxide nanoparticles could strengthen the resistance of apple rootstock B9 to saline-alkali stress.

Apple growth and development can be adversely affected by saline-alkali stress, which has become a significant factor restricting the high yield of the apple industry. In recent years, nanomaterials have become a potential source for plant growth and development. Titanium dioxide nanoparticles (TiO2 NPs) play an important role in multiple plant development processes, including mitigating environmental stress. In this study, one-year-old apple rootstock B9 stem cuttings were used as research objects. Different concentrations of TiO2 NPs were applied to the roots before saline-alkali treatment. Principal component analysis showed that 1gkg-1 TiO2 NPs treatment had the best effect in alleviating the stress for B9. It significantly reduced the damage to B9 under salt-alkali stress, increased the content of photosynthetic pigment, enhanced the performance of Photosystem II, and promoted photosynthesis. At the same time, the content of K+ was increased, and the ion toxicity was alleviated. In addition, TiO2 NPs have also been shown to reduce B9 cell damage and lipid peroxidation, increase antioxidant enzyme activity, and regulate the accumulation of solutes. Overall, this study provides a theoretical basis for TiO2 NPs to mitigate the adverse effects of plants under saline-alkali stress and provides useful insights for managing other plants affected by global salinity and alkalinity.

Transcription factors dealing with Iron-deficiency stress in plants: focus on the bHLH transcription factor family.

Iron (Fe), as an important micronutrient element necessary for plant growth and development, not only participates in multiple physiological and biochemical reactions in cells but also exerts a crucial role in respiration and photosynthetic electron transport. Since Fe is mainly present in the soil in the form of iron hydroxide, Fe deficiency exists universally in plants and has become an important factor triggering crop yield reduction and quality decline. It has been shown that transcription factors (TFs), as an important part of plant signaling pathways, not only coordinate the internal signals of different interaction partners during plant development, but also participate in plant responses to biological and abiotic stresses, such as Fe deficiency stress. Here, the role of bHLH transcription factors in the regulation of Fe homeostasis (mainly Fe uptake) is discussed with emphasis on the functions of MYB, WRKY and other TFs in the maintenance of Fe homeostasis. This review provides a theoretical basis for further studies on the regulation of TFs in Fe deficiency stress response.

Genome-wide identification of the CER1 gene family in apple and response of MdCER1-1 to drought stress.

Plant cuticular wax was a major consideration affecting the growth and quality of plants through protecting the plant from drought and other diseases. According to existing studies, CER1, as the core enzyme encoding the synthesis of alkanes, the main component of wax, can directly affect the response of plants to stress. However, there were few studies on the related functions of CER1 in apple. In this study, three MdCER1 genes in Malus domestica were identified and named MdCER1-1, MdCER1-2, and MdCER1-3 according to their distribution on chromosomes. Then, their physicochemical properties, sequence characteristics, and expression patterns were analyzed. MdCER1-1, with the highest expression level among the three members, was screened for cloning and functional verification. Real-time fluorescence quantitative PCR (qRT-PCR) analysis also showed that drought stress could increase the expression level of MdCER1-1. The experiment of water loss showed that overexpression of MdCER1-1 could effectively prevent water loss in apple calli, and the effect was more significant under drought stress. Meanwhile, MdYPB5, MdCER3, and MdKCS1 were significantly up-regulated, which would be bound up with waxy metabolism. Gas chromatography-mass spectrometer assay of wax fraction makes known that overexpression of MdCER1-1 apparently scaled up capacity of alkanes. The enzyme activities (SOD, POD) of overexpressed apple calli increased significantly, while the contents of proline increased compared with wild-type calli. In conclusion, MdCER1-1 can resist drought stress by reducing water loss in apple calli epidermis, increasing alkanes component content, stimulating the expression of waxy related genes (MdYPB5, MdCER3, and MdKCS1), and increasing antioxidant enzyme activity, which also provided a theoretical basis for exploring the role of waxy in other stresses.

Molecular cloning and functional characterization of MhHEC2-like genes in Malus halliana reveals it enhances Fe (iron) deficiency tolerance.

The basic helix-loop-helix (bHLH) family, as one of the largest families of transcription factors (TFs) in plants, plays crucial roles in regulating growth, development, and abiotic stress responses. However, studies on the association of the bHLH genes with apple iron (Fe) deficiency are limited. Here, multiple bHLH genes that responded to Fe deficiency were selected for quantitative real-time PCR in Malus halliana. The results showed that the expression of HEC2-like gene exerted more values compared to other genes under Fe deficiency stress, but the mechanism by which it regulates Fe deficiency stress is unclear. Subsequently, MhHEC2-like gene (ID: 103,455,961) was cloned from M. halliana for functional identification. We found that both transgenic Arabidopsis thaliana and tobacco displayed less chlorosis and more robust growth than wild-type (WT) controls under Fe deficiency stress. At the same time, the overexpressed apple calli grew prominently larger and better under Fe deficiency compared to the wild type. On the other hand, physiological index measurements revealed that overexpressed MhHEC2-like gene enhanced tolerance to Fe deficiency stress in A. thaliana and tobacco by promoting the synthesis of photosynthetic pigments, improving antioxidant enzyme activity, and enhancing Fe reduction, and strengthened tolerance to Fe deficiency stress in apple calli by reducing pH, boosting Fe reduction, and increasing antioxidant enzyme activity. To sum up, the overexpression of MhHEC2-like gene strengthened tolerance to Fe deficiency stress in Arabidopsis thaliana, tobacco, and apple calli.

LncRNA Gm16410 regulates PM2.5-induced lung Endothelial-Mesenchymal Transition via the TGF-ß1/Smad3/p-Smad3 pathway.

Exposure to PM2.5 can cause serious harm to the respiratory system. Until now, although many toxicological studies have shown that pulmonary fibrosis can be caused by long-term PM2.5 exposure, there is no evidence that Endothelial-Mesenchymal Transition (EndMT) can trigger the process of pulmonary fibrosis after exposure. LncRNAs are a class of non-coding RNAs detected in mammalian cells. Nevertheless, researchers have not found whether lncRNAs participate in PM2.5 induced EndMT during pathophysiological duration. The Balb/c mouse model was exposed to PM2.5 for 4 months by dynamic intoxication. The levels of specific endothelial and mesenchymal markers were evaluated by molecular biology experiments to elucidate the mechanisms of EndMT induced by PM2.5 in lung tissues. LncRNA microarray analysis of the established mouse model of PM2.5 exposure was performed. Based on a bioinformatics analysis and RT-qPCR analysis, lncRNA Gm16410 attracted our attention. The change of lncRNA Gm16410 in mouse pulmonary vascular endothelial cells (MHCs) exposed to PM2.5 was verified, and the mechanism of lncRNA Gm16410 in EndMT was discussed. The changes of cell function were evaluated by cell migration and proliferation experiments. The molecular biology experiments proved that PM2.5 induced EndMT by activating the TGF-ß1/Smad3/p-Smad3 pathway in vitro. The relationship of EndMT and lncRNA Gm16410 was verified in mouse lung tissues and MHC cells by PM2.5 exposure. The involvement of lncRNA Gm16410 in PM2.5-induced EndMT highlights the potential of lncRNA to promote pulmonary fibrosis under environmental pollution.

Construction and biological evaluation of different self-assembled nanoarchitectures of FZU-03,010.

Chemotherapy is currently one of the promising therapeutic methods for non-small-cell lung cancer (NSCLC), but the emergence of multidrug resistance (MDR) is the greatest obstacle to efficient drug delivery for successful chemotherapy. Nanotechnology-based drug delivery holds great promise to promote intracellular drug delivery to reverse MDR. In this work, we used our previously synthesized ursolic acid (UA) derivative, FZU-03,010 (F3), to prepare nanodrugs of F3 with different architectures and study the role of the structure on the physiochemical properties and the biological effects against A549 and its PTX-resistant A549/PTX lung cancer cells. Using different preparation methods, amphiphilic F3 could self-assemble into different structures such as nanoaggregates (F3-NA), vesicles (F3-VC), or nanoparticles (F3-NP) with different physiochemical properties. The self-assembled nanodrugs could be utilized for the entrapment of fluorophores and showed different cellular uptake efficiencies. The cytotoxicity results demonstrated that compared with UA, F3-NA and F3-NP could suppress A549 and A549/PTX cells viability more potently at lower concentration. In addition, F3-NA and F3-NP could induce G1 cell cycle arrest, cell apoptosis and caspase-3 activation more efficiently than that of UA. Furthermore, F3-NA and F3-NP could effectively inhibit PI3K/Akt pathway and decrease the expression of Bcl-2 and the cell cycle-dependent kinase inhibitors p-ERK1/2 and Cyclin D1 in both A549 and A549/PTX cells. In conclusion, our results suggest that the UA derivative F3 is more potent in inhibiting cancer cell proliferation, and F3-NA and F3-NP have the potential to be developed as a therapeutic agent for resistant NSCLC cells.

Discovery of FZU-03,010 as a self-assembling anticancer amphiphile for acute myeloid leukemia.

Recently various drug candidates with excellent anticancer potency have been demonstrated, whereas their clinical application largely suffers from several limitations especially poor solubility. Ursolic acid (UA) as one of ubiquitous pentacyclic triterpenes in plantkingdom exhibited versatile antiproliferative effects in various cancer cell lines. However, the unfavorable pharmaceutical properties became the main obstacle for its clinical development. With the aim of development of novel derivatives with enhanced potency, a series of diversified UA amphiphiles have been designed, synthesized, and pharmacologically evaluated. Amphiphile 10 (FZU-03,010) with significant improved antiproliferative effect can self-assemble into stable nanoparticles in water, which may serve as a promising candidate for further development.

Development of a Concise Synthetic Approach to Access Oroxin A.

A novel environment-friendly method to access bioactive oroxin A through a one-pot/two-step process from naturally abundant and inexpensive baicalin is described. The procedure presented here has several advantages including clean, one-pot, synthetic ease, and large-scale feasibility. This work also provides a model strategy for rapid and diverse access to natural molecules sharing the common skeleton of this family.

Novel visible-light-induced photocurable tissue adhesive composed of multiply styrene-derivatized gelatin and poly(ethylene glycol) diacrylate.

A novel photocurable tissue adhesive glue, which is composed of styrene-derivatized (styrenated) gelatin, poly(ethylene glycol) diacrylate (PEGDA), and carboxylated camphorquinone in phosphate-buffered saline (PBS), was prepared. The prototype formulation suitable for arterial repair was determined based on the gel yield, degree of swelling, tissue adhesive strength, and breaking (or burst) strength in vitro. The formulated photocurable tissue adhesive glue with an appropriate viscosity was converted to a water-swollen gel within 1 min of visible light irradiation. The tissue adhesive glue, which was coated on a rat abdominal aorta incised with a pair of scissors, was immediately converted to a swollen gel upon subsequent irradiation with visible light, and concomitantly hemostasis was completed. Histological examination showed that the produced gel was tightly adhered to the artery shortly after photoirradiation. The gel gradually degraded with time and was completely absorbed within 4 weeks after treatment. These results indicate that the photocurable glue developed here may serve as a tissue adhesive glue applicable to vascular surgery.