查找使用阿拉丁产品的科研文献

Non-canonical role of UCKL1 on ferroptosis defence in colorectal cancer

Weili Wu,Yingying Zhao,Baifu Qin,Xin Jiang,Chuyue Wang,Rong Hu,Rui Ma,Mong-Hong Lee,Huanliang Liu,Kai Li,Ping Yuan

Nonenzymatic Sequestering of Formaldehyde into the Antibiotic Methylene-Bridged Dimer Phaeochromycin F by Streptomyces sp. OUCMDZ-4982 as a Possible Multipronged Chemical Defense Mechanism

Weihong Wang,Jiaxu Shang,Shupeng Yin,Kunyu Xia,Rui Ma,Weiming Zhu,Peng Fu

Metabolites with high chemical reactivity serve important roles in chemical defenses of organisms. Formaldehyde, as a simple and highly reactive small molecule, can be produced by microorganisms, plants, and animals. Its toxicity is well known, but information about its other biological functions remains scarce. Here, we report that the natural product SEK34b produced by Streptomyces species can react nonenzymatically with formaldehyde in water to yield the methylene-bridged dimer phaeochromycin F. This process can eliminate the toxic substance formaldehyde produced by Staphylococcus aureus. Furthermore, there is a substantial inhibitory impact of phaeochromycin F on S. aureus. We hypothesize that these constitute an integrated system of defense and attack of Streptomyces species against competitors. Our study indicates that formaldehyde can react with vancomycin and tigecycline under mild conditions to generate the derivatives bearing an imidazolidin-4-one moiety, thereby reducing the antibacterial activity of these antibiotics. These data provide a possible chemical interaction mechanism of bacteria involving the nonenzymatic reactions of formaldehyde with highly reactive natural products.

Odorant binding protein TcOBPC02 contributes to phytochemical defense in the red flour beetle, Tribolium castaneum

Shanshan Gao,Mengyi Guo,Weicheng Yu,Wenbo Miao,Haofei Ya,Dongfeng Liu,Ruimin Li,Kunpeng Zhang

The red flour beetle, Tribolium castaneum , is an agricultural and storage pest with a global distribution. Studies have shown that eucalyptol has strong contact toxicity against larvae of this beetle, whereas odorant binding proteins (OBPs) are known to contribute to larval defenses against this phytochemical toxin. However, the mechanisms underlying the protective effect of insect OBP s against eucalyptol remain unclear. Here, TcOBPC02 from T . castaneum was cloned and characterized. Gene expression profile analysis showed that TcOBPC02 is highly expressed at early larval and early pupal stages. Additionally, tissue expression profiling revealed that, in the adult, TcOBPC02 was most highly expressed in the head, followed by the epidermis, whereas in larvae, TcOBPC02 was mainly expressed in hemolymph and the epidermis. These developmental stages and tissues that exhibit high TcOBPC02 expression are closely related to the detoxification of heterologous substances. Furthermore, the mRNA level of TcOBPC02 was significantly increased after exposure to eucalyptol, whereas TcOBPC02 -targeted RNA interference increased the susceptibility of T. castaneum to eucalyptol, indicating that TcOBPC02 participates in the tolerance of this beetle to eucalyptol. Additionally, recombinant TcOBPC02 was expressed in Escherichia coli and isolated, enabling a straightforward fluorescence competition binding assay. In combination, these results have demonstrated that TcOBPC02 is required for defenses against phytochemicals in T. castaneum . This study provides a theoretical basis for understanding the mechanisms underlying the degradation of exogenous toxicants in insects and adds to the repertoire of potential target genes for pest control.

Repellence or attraction: secondary metabolites in pepper mediate attraction and defense against Spodoptera litura

Ge-Ge Yuan,Lin-Chao Zhao,Yuan-Wen Du,Huan Yu,Xiao-Bin Shi,Wen-Chao Chen,Gong Chen

BACKGROUND Resistance to insect pests is an important self-defense characteristic of pepper plants. However, the resistance of different pepper cultivars to Spodoptera litura larvae, one of the main insect pest species on pepper, is not well understood. RESULTS Among seven pepper cultivars evaluated, cayenne pepper ‘FXBX’ showed the highest repellency to third instar S. litura larvae, Chao tian chili pepper ‘BLTY2’ showed the lowest repellency. Plant volatiles (1-hexene, hexanal, β -ionone, ( E , E )-2,6-nonadienal, and methyl salicylate) affected host selection by S. litura . Among these, 1-hexene, hexanal, and β -ionone at concentrations naturally-released by pepper leaves were found to repel S . litura . Interestingly, S. litura larvae fed on the larva-attracting pepper cultivar, (BLTY2) had an extended developmental period, which was about 13 days longer than larvae fed on FXBX. Besides, the survival rate of larvae fed on BLTY2 was 22.5 ± 0.0%, indicating that the leaves of BLTY2 can kill S. litura larvae. Correlation analysis showed that larval survival rate, emergence rate, female adult longevity, and pupal weight were positively correlated with the vitamin C, amino acids, protein, cellulose, and soluble sugar contents, but were negatively correlated with wax and flavonoids contents. CONCLUSION We identified two different modes of direct defense exhibited by pepper cultivars against S. litura . One involves the release of repellent volatiles to avoid been fed on (FXBX cultivar). The other involves the inhibition of the growth and development or the direct killing of S. litura larvae which feeds on it (BLTY2 cultivar). © 2022 Society of Chemical Industry.

Odorant binding protein C12 is involved in the defense against eugenol in Tribolium castaneum

Shanshan Gao,Ruixue Lu,Yonglei Zhang,Haidi Sun,Siying Li,Kunpeng Zhang,Ruimin Li

Tribolium castaneum ( T. castaneum ) is a worldwide pest of stored grain that mainly harms flour, and not only causes serious loss of flour quality but also leads to deterioration of flour quality. Chemical detection plays a key role in insect behavior, and the role of odorant-binding proteins (OBPs) in insect chemical detection has been widely studied. However, the mechanism of OBPs in insect defense against exogenous toxic substances is still unclear. In this study, biochemical analysis showed that eugenol , the active component of A. vulgaris essential oil , significantly induced the expression of the OBP gene OBPC12 from T. castaneum ( TcOBPC12 ). The mortality of late larvae treated with eugenol was higher than that of the control group after RNA interference (RNAi) against TcOBPC12 , which indicates that the OBP gene is involved in the eugenol defense mechanism and leads to a decrease in sensitivity to eugenol. Tissue expression profiling showed that the expression of TcOBPC12 in the epidermis, hemolymph, and intestine was higher than in other larval tissues, and TcOBPC12 was expressed mainly in the epidermis, head, and fat body of adults. The developmental expression profile showed that the expression of TcOBPC12 in late eggs, early and late larval stages, and late adult stages was higher than in other developmental stages. These data suggest that TcOBPC12 may be involved in the absorption of exogenous toxic substances by the larvae from T. castaneum . Our results provide a theoretical basis for the metabolism and degradation mechanism of exogenous toxic substances and help explore more potential target genes of insect pests .

Herbivore-Induced (Z)-3-Hexen-1-ol is an Airborne Signal That Promotes Direct and Indirect Defenses in Tea (Camellia sinensis) under Light

Yinyin Liao,Haibo Tan,Guotai Jian,Xiaochen Zhou,Luqiong Huo,Yongxia Jia,Lanting Zeng,Ziyin Yang

Tea (Camellia sinensis) is the most popular nonalcoholic beverage worldwide. During cultivation, tea plants are susceptible to herbivores and pathogens, which can seriously affect tea yield and quality. A previous report showed that (Z)-3-hexenol is a potentially efficient defensive substance. However, the molecular mechanism mediating (Z)-3-hexenol signaling in tea plants and the resulting effects on plant defenses remain uncharacterized. To clarify the signaling mechanisms in which (Z)-3-hexenol and light are involved, the gene transcription and metabolite levels were assessed, respectively. This study demonstrated that tea plants rapidly and continuously release (Z)-3-hexen-1-ol in response to an insect infestation. (Z)-3-Hexen-1-ol absorbed by adjacent healthy plants would be converted into three insect defensive compounds: (Z)-3-hexenyl-glucoside, (Z)-3-hexenyl-primeveroside, and (Z)-3-hexenyl-vicianoside identified with laboratory-synthesized standards. Moreover, (Z)-3-hexen-1-ol also activates the synthesis of jasmonic acid to enhance the insect resistance of tea plants. Additionally, a continuous light treatment induces the accumulation of (Z)-3-hexenyl-glycosides. Hence, (Z)-3-hexenol serves as a light-regulated signaling molecule that activates the systemic defenses of adjacent plants. Our study reveals the molecular mechanisms by which biotic and abiotic factors synergistically regulate the signaling functions of herbivore-induced plant volatiles in plants, providing valuable information for future comprehensive analyses of the systemic defense mechanisms in plants.

Transcriptional regulation modulates terpenoid biosynthesis of Pinus elliottii under drought stress

Yini Zhang,Shu Diao,Xianyin Ding,Jiaming Sun,Qifu Luan,Jingmin Jiang

Global climate change has increased the frequency and severity of droughts, which may affect the biosynthesis of coniferous terpenes, but the regulatory mechanism is still unclear. We explored the mechanisms of terpenoid regulation in response to drought stress by resolving changes in terpenoid composition and gene expression under drought stress to better understand the expression profile of terpenoid synthesis in slash pine . We obtained three main results: (1) A total of 1393 differentially expressed genes (DEGs) were identified, mainly including MYB, AP2/ERF, WRKY and other transcription factors, which were reported to be associated with plant resistance. Real-time quantitative PCR (RT-qPCR) verified the reliability of transcriptomic data, and the analysis of its results shows a close correlation with the data obtained by RNA-seq. (2) A total of 39 DEGs encoding 7 types of the proteins that were identified in the terpene synthesis pathway; what’s more, TPS (e.g., PITA_24906, PITA_00655, PITA_09277) and CYP720B11 (PITA_22711) showed high expressions in diterpene synthesis. (3) A weighted coexpression network analysis (WGCNA) showed high correlations between levopimaric acid content and module genes expression. Network visualization of the 70 hub genes revealed this high degree of connectivity between PITA_24906 and other genes, suggesting that PITA_24906 might play a regulatory role in levopimaric acid under drought stress. Thus, the results of this study will lead to a better understanding of the defense mechanisms of slash pine and provide a basic reference for the management and genetic improvement of slash pine stands.

A two-in-one molybdenum disulfide-chitosan nanoparticles system for activating plant defense mechanisms and reactive oxygen species to treat Citrus Huanglongbing

Guiyun Deng,Feifan Lu,Shuojun Li,Yuying Long,Jianghong Wu,Xiaofeng Guo,Chunyin Li,Zhiyong Song,Mohamed F. Foda,Fang Ding,Heyou Han

Citrus Huanglongbing (HLB) poses an enormous challenge to Citrus cultivation worldwide, necessitating groundbreaking interventions beyond conventional pharmaceutical methods. In this study, we propose molybdenum disulfide-chitosan nanoparticles (MoS 2 -CS NPs) through electrostatic adsorption, preserving the plant-beneficial properties of molybdenum disulfide (MoS 2 ), while enhancing its antibacterial effectiveness through chitosan modification. MoS 2 -CS NPs exhibited significant antibacterial efficacy against RM1021 , and the closest relatives to Candidatus Liberibacter asiaticus ( C Las), Erwinia carotovora , and Xanthomonas citri achieved survival rates of 7.40 % ± 1.74 %, 8.94 % ± 1.40 %, and 6.41 % ± 0.56 %, respectively. In vivo results showed, C Las survival rate of 10.42 % ± 3.51 %. Furthermore, treatment with MoS 2 -CS NPs resulted in an increase in chlorophyll and carotenoid content. Concomitantly, a significant reduction in malondialdehyde (MDA), soluble sugar, hydrogen peroxide (H 2 O 2 ), and starch contents was also observed. Mechanistically, MoS 2 -CS NPs enhanced the activity of antioxidant-related enzymes by upregulating the expression of antioxidant genes, thereby galvanizing the antioxidant system to alleviate oxidative stress. Collectively, this dual functionality—combining direct antibacterial action with the activation of plant defense mechanisms—marks a promising strategy for managing Citrus Huanglongbing and suggests potential agricultural applications for MoS 2 -based antibacterial treatments.

Self-defending mechanism of C/TaC‒SiC composites under 2100°C cyclic ablation environment

Mingde Tong,Xinhao Shi,Tao Feng,Ying Dai,Pengfei He

To achieve the repeatability of aerospace thermal components, C/TaC‒SiC composites were fabricated. Cycle ablation and bending tests were carried out. After 3 × 60 s of ablation beyond 2100°C, the mechanical property retention rate was 80.9%. Interestingly, a reaction similar to “ouroboros ring,” in which the cyclic reactions of “TaC being oxidized to Ta 2 O 5 and Ta 2 O 5 being reduced to TaC,” occurred in the central ablation region of C/TaC‒SiC composites. On the one hand, the continuous generation of TaC could prevent liquid state Ta 2 O 5 from being blown off central ablation region, playing a similar role in “water and soil conservation.” On the other hand, liquid Ta 2 O 5 covered the surface of C/TaC‒SiC composites during ablation process, contributing to block the inward permeation of oxidized gases. In addition, novel “Grotto” structures were detected in the transitional ablation region of C/TaC‒SiC composites. The formation reason of the “Grotto” structure has also been discussed.

Multi-omics reveals phenol-based coordinated defense of Sparganium stoloniferum rhizoma

Mengru Sang,Qinan Liu,Dishuai Li,Jingjie Dang,Shilin Dai,Chanchan Liu,Qinan Wu

Sparganium stoloniferum is a widely distributed aquatic medicinal plant that exhibits exceptional tolerance to environmental stress. Interestingly, the phenols in S. stoloniferum which have medicinal properties, are defensive compounds. Studies integrating transcriptome, proteome, and metabolome analyses have highlighted the phenylpropanoid and flavonoid biosynthesis pathways, which are related to the defense mechanisms of S. stoloniferum . During the growth process, S. stoloniferum rhizoma (SL) accumulates lignin, forming a physical defense, and phenylpropanoids and flavonoids derived during the lignin biosynthesis process provide chemical defense. In this study, a map of the molecular processes involved in the coordinated defense of S. stoloniferum was generated. The expression patterns of genes involved in the coordinated defense of SL were consistent with the omics results. The cDNA of the phenylalanine ammonia-lyase ( PAL ) gene from S. stoloniferum ( Ss PAL) was cloned. The recombinant protein Ss PAL showed good affinity and catalytic activity for L-phenylalanine. Heat stress experiments indicated that genes related to phenol biosynthesis were upregulated when S. stoloniferum responded to stress. Therefore, phenols played a crucial defense role when S. stoloniferum was at an early developmental stage or responded to stress in a short time. In contrast, the physical defense mainly relied on lignin formation, which was the main defense mechanism of SL in the late growth stage. Based on these results, we discuss the causes of phenolic pharmacological substance formation in medicinal aquatic plants. These results provide new insights into the defense strategies of aquatic plants.

Enhanced marine antifouling hydrogel coatings achieved through simultaneous enhancement of contact-killing, low surface energy and fluorescence properties

Guangling He,Shuqing Wei,Yuhao Yue,Lei Dong,Liangmin Yu

Hydrogel is recognized as highly promising antifouling coatings. The introduction of other antifouling strategies has emerged as an essential research direction for enhancing hydrogel antifouling applications. However, simultaneous integration of multiple antifouling strategies within the same hydrogel remains challenging, while attenuation of hydrogel hydration layer antifouling effect during functionalization is still problematic. Herein, a multifunctional coating combines the hydrogel hydration layer surface with multiple antifouling mechanisms including low surface energy characteristics, cationic contact-killing structure, and fluorescence performance was developed. Through elevation of 2-(dimethylamino)ethyl methacrylate (DM) content, the hydration layer characteristics, low surface energy characteristics, cationic contact-killing effect, and fluorescence performance were simultaneously enhanced. This approach effectively overcomes antagonistic interactions between co-existing multiple antifouling mechanisms. Crucially, the fluorescence functionality was engineered in this coating without employing exogenous fluorophores through precisely designed intermolecular aggregation. Meanwhile, an enhanced dual-stage defense was imparted to the coatings through synergistic mechanism integration. First stage of antifouling defense: hydration layer, low surface energy, and fluorescence performance collectively impart enhanced fouling-resistance adhesion capability into coating. Second stage of antifouling defense: surface-adhered organisms are killed via contact-killing. Consequently, the hydrogel demonstrates excellent anti-protein adsorption performance (minimum normalized value <1 %), algal adhesion and growth inhibition performance, inhibition of bacterial growth (up to 98.27 %) and adhesion performance (up to 96.36 %). It employs absolutely no metallic antifouling agents and fluorescent agents, thereby providing important insights for eco-friendly marine antifouling coatings.

Plant jasmonic acid mediated contrasting effects of two citrus aphid species on Diaphorina citri Kuwayama

Jing Gao,TongLai Tao,Steven P. Arthurs,Fengxian Ye,Xincheng An,Mubasher Hussain,Runqian Mao

Background Herbivores may influence each other directly and through plant mediated inter-specific interactions. The Asian citrus psyllid ( Diaphorina citri Kuwayama) and citrus aphids are key pests that can co-exist on citrus, but their plant-mediated interaction between them is unknown. Here we investigated plant-mediated effect of two citrus aphid species, the polyphagous Aphis spiraecola Patch and the oligophagous Aphis ( Toxoptera ) citricidus (Kirkaldy) on the feeding behavior and reproduction of Diaphorina citri , and explored the underlying mechanisms. Results In comparison with those on aphid free plants, Diaphorina citri had decreased reproduction and reduced phloem feeding on Aphis spiraecola pre-infested plants, while the reproduction and feeding efficiency were increased on Aphis citricidus pre-infested plants. Jasmonic acid (JA) dependent defense was significantly activated by Diaphorina citri feeding on Aphis spiraecola pre-infested plants, but was suppressed by Diaphorina citri feeding on Aphis citricidus pre-infested plants compared with that on aphid free plant. By contrast, only one tested marker gene in salicylic acid (SA) signaling was activated by Diaphorina citri feeding on Aphis spiraecola pre-infested plants. Furthermore, exogenous application of methyl jasmonate, but not SA, conferred resistance against Diaphorina citri in our citrus trials. Conclusion Our results indicate that pre-infestation by two citrus aphid species differentially altered Diaphorina citri induced citrus JA dependent defense, which resulted in different effect on subsequent Diaphorina citri performance. © 2022 Society of Chemical Industry.