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The discovery of superconductivity in layered MgB2 has renewed interest in the search for high-temperature conventional superconductors, leading to the synthesis of numerous hydrogen-dominated materials with high critical temperatures (Tc) under high pressures. However, achieving a high-Tc superconductor under ambient pressure remains a challenging goal. In this study, we propose a novel approach to realize a high-temperature superconductor under ambient pressure by introducing a hexagonal H monolayer into the hexagonal close-packed magnesium lattice, resulting in a new and stable few-hydrogen metal-bonded layered magnesium hydride (Mg4)2H1. This compound exhibits superior ductility compared to multi-hydrogen, cuprate, and iron-based superconductors due to its metallic bonding. Our unconventional strategy diverges from the conventional design principles used in hydrogen-dominated covalent high-temperature superconductors. Using anisotropic Migdal-Eliashberg equations, we demonstrate that the stable (Mg4)2H1 compound is a typical phonon-mediated superconductor, characterized by strong electron-phonon coupling and an excellent Tc of 37 K under ambient conditions, comparable to that of MgB2. Our findings not only present a new pathway for exploring high-temperature superconductors but also provide valuable insights for future experimental synthesis endeavors.
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On a global basis, potato cyst nematodes (Globodera spp. Skarbilovich 1959 [Behrens 1975]) are one of the most serious soilborne pathogens in potato (Solanum tuberosum L.) production. In 2019 to 2020, 188 soil samples were taken from rhizosphere soil associated with the roots of stunted and chlorotic potato plants in the main potato-growing areas of Yunnan and Sichuan Provinces of China. Globodera rostochiensis Wollenweber 1923 (Skarbilovich 1959) was recovered from 112 of the samples. Nematode identification was as confirmed by morphometric, light microscopy, electron microscopy, and molecular methodologies. Population densities of G. rostochiensis ranged from 47.0 to 69.0 eggs/g of soil. A BLASTn homology search program was used to compare the sequences of populations of G. rostrochienses from Yunnan and Sichuan Provinces with populations of other Heteroderinae spp. and populations of G. rostochiensis from other nations. Although potato has been grown in China for at least 400 years and the nation produces more potato than any other country, potato cyst nematodes were not reported in China until 2022.
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Nematoides , Solanum tuberosum , Animais , China , SoloRESUMO
INTRODUCTION: Plant parasitic cyst nematodes secrete a number of effectors into hosts to initiate formation of syncytia and infection causing huge yield losses. OBJECTIVES: The identified cyst nematode effectors are still limited, and the cyst nematode effectors-involved interaction mechanisms between cyst nematodes and plants remain largely unknown. METHODS: The t-SNARE domain-containing effector in beet cyst nematode (BCN) was identified by In situ hybridization and immunohistochemistry analyses. The mutant of effector gene was designed by protein structure modeling analysis. The functions of effector gene and its mutant were analyzed by genetic transformation in Arabidopsis and infection by BCN. The protein-protein interaction was analyzed by yeast two hybrid, BiFC and pulldown assays. Gene expression was assayed by quantitative real-time PCR. RESULTS: A t-SNARE domain-containing BCN HsSNARE1 was identified as an effector, and its mutant HsSNARE1-M1 carrying three mutations (E141D, A143T and -148S) that altered regional structure from random coils to α-helixes was designed and constructed. Transgenic analyses indicated that expression of HsSNARE1 significantly enhanced while expression of HsSNARE1-M1 and highly homologous HgSNARE1 remarkably suppressed BCN susceptibility of Arabidopsis. HsSNARE1 interacted with AtSNAP2 and AtPR1 via its t-SNARE domain and N-terminal, respectively, while HsSNARE1-M1/HgSNARE1 could not interact with AtPR1 but bound AtSNAP2. AtSNAP2, AtSHMT4 and AtPR1 interacted pairwise, but neither HsSNARE1 nor HsSNARE1-M1/HgSNARE1 could interact with AtSHMT4. Expression of HsSNARE1 significantly suppressed while expression of HsSNARE1-M1/HgSNARE1 considerably induced both AtSHMT4 and AtPR1 in transgenic Arabidopsis infected with BCN. Overexpression of AtPR1 significantly suppressed BCN susceptibility of Arabidopsis. CONCLUSIONS: This work identified a t-SNARE-domain containing cyst nematode effector HsSNARE1 and deciphered a molecular mode of action of the t-SNARE-domain containing cyst nematode effectors that HsSNARE1 promotes cyst nematode disease by interaction with both AtSNAP2 and AtPR1 and significant suppression of both AtSHMT4 and AtPR1, which is mediated by three structure change-causing amino acid residues.
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Proteínas de Arabidopsis , Arabidopsis , Beta vulgaris , Nematoides , Animais , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Beta vulgaris/metabolismo , Beta vulgaris/parasitologia , Nematoides/metabolismo , MutaçãoRESUMO
The rhg1-a GmSNAP18 (an α-SNAP) and Rhg4 GmSHMT08 are two major cloned genes conferring soybean cyst nematode resistance in Peking-type soybeans, but the application of α-SNAPs and SHMTs in cyst nematode management remains elusive. In this study, GmSNAP18 and GmSHMT08, together with their orthologs in Arabidopsis, AtSNAP2 (an α-SNAP) and AtSHMT4, were individually transformed into Arabidopsis Col-0 to generate the transgenic lines, and the growth of transgenic plants, beet cyst nematode (BCN) infection phenotypes, and AtSNAP2, AtSHMT4, and AtPR1 expression patterns were analyzed using Arabidopsis-BCN compatible interaction system, in addition with protein-protein interaction assay. Pulldown and BiFC assays revealed that GmSNAP18 and GmSHMT08 interacted with AtSHMT4 and AtSNAP2, respectively. Plant root growth was not impacted by overexpression of GmSNAP18 and AtSNAP2. However, overexpression of GmSHMT08 and AtSHMT4 both increased plant height, additionally, overexpression of GmSHMT08 decreased rosette leaf size. Overexpression of GmSNAP18 and GmSHMT08 both suppressed AtPR1 expression and significantly enhanced BCN susceptibility, while overexpression of AtSNAP2 and AtSHMT4 both substantially boosted AtPR1 expression and remarkably enhanced BCN resistance, in transgenic Arabidopsis. Overexpression of GmSNAP18 reduced, while overexpression of AtSNAP2 unaltered AtSHMT4 expression. Overexpression of GmSHMT08 and AtSHMT4 both suppressed AtSNAP2 expression in transgenic Arabidopsis. Thus, different expression patterns of AtPR1 and AtSHMT4 are likely associated with opposite BCN infection phenotypes of Arabidopsis between overexpressing GmSNAP18 and AtSNAP2, and between overexpressing GmSHMT08 and AtSHMT4; and boosted AtPR1 expression are required for enhanced BCN resistance in Arabidopsis. All these results establish a basis for extension of α-SNAPs and SHMTs in cyst nematode management.
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Arabidopsis , Beta vulgaris , Cistos , Infecções por Nematoides , Tylenchoidea , Animais , Arabidopsis/genética , Tylenchoidea/genética , Doenças das Plantas/genética , Proteínas de Ligação a Fator Solúvel Sensível a N-Etilmaleimida/genética , Glycine max/genética , Plantas Geneticamente Modificadas/genética , FenótipoRESUMO
KEY MESSAGE: Soybean acyl-ACP thioesterase gene family have been characterized; GmFATA1A mutants were discovered to confer high oleic acid, while GmFATB mutants presented low palmitic and high oleic acid seed content. Soybean oil stability and quality are primarily determined by the relative proportions of saturated versus unsaturated fatty acids. Commodity soybean typically contains 11% palmitic acid, as the primary saturated fatty acids. Reducing palmitic acid content is the principal approach to minimize the levels of saturated fatty acids in soybean. Though high palmitic acid enhances oxidative stability of soybean oil, it is negatively correlated with oil and oleic acid content and can cause coronary heart diseases for humans. For plants, acyl-acyl carrier protein (ACP) thioesterases (TEs) are a group of enzymes to hydrolyze acyl group and release free fatty acid from plastid. Among them, GmFATB1A has become the main target to genetically reduce the palmitic acid content in soybean. However, the role of members in soybean acyl-ACP thioesterase gene family is largely unknown. In this study, we characterized two classes of TEs, GmFATA, and GmFATB in soybean. We also denominated two GmFATA members and discovered six additional members that belong to GmFATB gene family through phylogenetic, syntenic, and in silico analysis. Using TILLING-by-Sequencing+, we identified an allelic series of mutations in five soybean acyl-ACP thioesterase genes, including GmFATA1A, GmFATB1A, GmFATB1B, GmFATB2A, and GmFATB2B. Additionally, we discovered mutations at GmFATA1A to confer high oleic acid (up to 34.5%) content, while mutations at GmFATB presented low palmitic acid (as low as 5.6%) and high oleic acid (up to 36.5%) phenotypes. The obtained soybean mutants with altered fatty acid content can be used in soybean breeding program for improving soybean oil composition traits.
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Ácidos Graxos/química , Glycine max/genética , Proteínas de Plantas/genética , Óleo de Soja/química , Tioléster Hidrolases/genética , Família Multigênica , Ácido Oleico , Ácido Palmítico , Filogenia , Melhoramento Vegetal , Sementes/química , Glycine max/enzimologiaRESUMO
Reverse genetic approaches have been widely applied to study gene function in crop species; however, these techniques, including gel-based TILLING, present low efficiency to characterize genes in soybeans due to genome complexity, gene duplication, and the presence of multiple gene family members that share high homology in their DNA sequence. Chemical mutagenesis emerges as a genetically modified-free strategy to produce large-scale soybean mutants for economically important traits improvement. The current study uses an optimized high-throughput TILLING by target capture sequencing technology, or TILLING-by-Sequencing+ (TbyS+), coupled with universal bioinformatic tools to identify population-wide mutations in soybeans. Four ethyl methanesulfonate mutagenized populations (4032 mutant families) have been screened for the presence of induced mutations in targeted genes. The mutation types and effects have been characterized for a total of 138 soybean genes involved in soybean seed composition, disease resistance, and many other quality traits. To test the efficiency of TbyS+ in complex genomes, we used soybeans as a model with a focus on three desaturase gene families, GmSACPD, GmFAD2, and GmFAD3, that are involved in the soybean fatty acid biosynthesis pathway. We successfully isolated mutants from all the six gene family members. Unsurprisingly, most of the characterized mutants showed significant changes either in their stearic, oleic, or linolenic acids. By using TbyS+, we discovered novel sources of soybean oil traits, including high saturated and monosaturated fatty acids in addition to low polyunsaturated fatty acid contents. This technology provides an unprecedented platform for highly effective screening of polyploid mutant populations and functional gene analysis. The obtained soybean mutants from this study can be used in subsequent soybean breeding programs for improved oil composition traits.
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Glycine max/metabolismo , Proteínas de Plantas/metabolismo , Óleo de Soja/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Mutação/genética , Proteínas de Plantas/genética , Glycine max/genéticaRESUMO
KEY MESSAGE: GhMYB4 acts as a negative regulator in lignin biosynthesis, which results in alteration of cell wall integrity and activation of cotton defense response. Verticillium wilt of cotton (Gossypium hirsutum) caused by the soil-borne fungus Verticillium dahliae (V. dahliae) represents one of the most important constraints of cotton production worldwide. Mining of the genes involved in disease resistance and illuminating the molecular mechanisms that underlie this resistance is of great importance in cotton breeding programs. Defense-induced lignification in plants is necessary for innate immunity, and there are reports of a correlation between increased lignification and disease resistance. In this study, we present an example in cotton whereby plants with reduced lignin content also exhibit enhanced disease resistance. We identified a negative regulator of lignin synthesis, in cotton encoded in GhMYB4. Overexpression of GhMYB4 in cotton and Arabidopsis enhanced resistance to V. dahliae with reduced lignin deposition. Moreover, GhMYB4 could bind the promoters of several genes involved in lignin synthesis, such as GhC4H-1, GhC4H-2, Gh4CL-4, and GhCAD-3, and impair their expression. The reduction of lignin content in GhMYB4-overexpressing cotton led to alterations of cell wall integrity (CWI) and released more oligogalacturonides (OGs) which may act as damage-associated molecular patterns (DAMPs) to stimulate plant defense responses. In support of this hypothesis, exogenous application with polygalacturonic acid (PGA) in cotton activated biosynthesis of jasmonic acid (JA) and JA-mediated defense against V. dahliae, similar to that described for cotton plants overexpressing GhMYB4. This study provides a new candidate gene for cotton disease-resistant breeding and an increased understanding of the relationship between lignin synthesis, OG release, and plant immunity.
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Ascomicetos/patogenicidade , Gossypium/metabolismo , Gossypium/microbiologia , Lignina/biossíntese , Proteínas de Plantas/genética , Acetatos/farmacologia , Arabidopsis/genética , Arabidopsis/microbiologia , Ciclopentanos/farmacologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Gossypium/efeitos dos fármacos , Gossypium/genética , Lignina/genética , Oxilipinas/farmacologia , Pectinas/farmacologia , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Imunidade Vegetal , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Ácido Salicílico/farmacologia , Fatores de Transcrição/genéticaRESUMO
Alpha-linolenic acid (ALA, 18:3Δ9,12,15) and γ-linolenic acid \ (GLA, 18:3Δ6,9,12) are important trienoic fatty acids, which are beneficial for human health in their own right, or as precursors for the biosynthesis of long-chain polyunsaturated fatty acids. ALA and GLA in seed oil are synthesized from linoleic acid (LA, 18:2Δ9,12) by the microsomal ω-3 fatty acid desaturase (FAD3) and Δ6 desaturase (D6D), respectively. Cotton (Gossypium hirsutum L.) seed oil composition was modified by transforming with an FAD3 gene from Brassica napus and a D6D gene from Echium plantagineum, resulting in approximately 30% ALA and 20% GLA, respectively. The total oil content in transgenic seeds remained unaltered relative to parental seeds. Despite the use of a seed-specific promoter for transgene expression, low levels of GLA and increased levels of ALA were found in non-seed cotton tissues. At low temperature, the germinating cottonseeds containing the linolenic acid isomers elongated faster than the untransformed controls. ALA-producing lines also showed higher photosynthetic rates at cooler temperature and better fiber quality compared to both untransformed controls and GLA-producing lines. The oxidative stability of the novel cottonseed oils was assessed, providing guidance for potential food, pharmaceutical and industrial applications of these oils.
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Fibra de Algodão , Óleo de Sementes de Algodão/metabolismo , Germinação/genética , Gossypium/genética , Fotossíntese/genética , Sementes/crescimento & desenvolvimento , Ácido alfa-Linolênico/metabolismo , Ácido gama-Linolênico/metabolismo , Brassica napus/genética , Resposta ao Choque Frio , Fibra de Algodão/normas , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Engenharia Genética , Gossypium/metabolismo , Plantas Geneticamente Modificadas , Sementes/metabolismo , Ácido alfa-Linolênico/genética , Ácido gama-Linolênico/genéticaRESUMO
Allium macrostemon saponin is a traditional Chinese medicine that exhibits anti-atherosclerosis effects. However, the mechanism of its action has not been fully clarified. Platelet activation induced by CD40L plays an important role in the process of atherosis. In the present study, we demonstrate for the first time that A. macrostemon saponin inhibits platelet activation induced by CD40L. Moreover, the effects of saponin on platelet activation were achieved by activation of the classical CD40L-associated pathway, including the PI3K/Akt, MAPK and NF-κB proteins. In addition, the present study further demonstrated that saponin exhibited an effect on the TRAF2-mediated ubiquitination degradation, which contributed to the inhibition of the CD40 pathway and its downstream members. The findings determine that A. macrostemon saponin inhibits activation of platelets via activation of downstream proteins of the CD40 pathway. This in turn affected TRAF2-associated ubiquitination degradation and caused an anti-thrombotic effect.
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ETHNOPHARMACOLOGIC RELEVANCE: Berberine (BBR) is a naturally occurring alkaloid compound that can be found in Chinese medicinal herbs such as Rhizoma Coptidis and Phellodendri Cortex. These BBR containing herbs are commonly used by Chinese medicine doctors to treat cancers including melanoma. In this study, we explored proteins potentially involved in the anti-melanoma effects of BBR using computational and experimental approaches. MATERIALS AND METHODS: Target proteins of BBR were predicted using the reverse pharmacophore screening, molecular docking and molecular dynamics. Anti-melanoma activities of BBR in melanoma cells were examined by MTT and EdU proliferation assays. Effects of BBR on activities of target proteins in melanoma cells were examined by Western blotting or fluorescence assay. RESULTS: Ten proteins implicated in cancer and with high fit-score in the reverse pharmacophore screening were selected as potential targets of BBR. Molecular docking and molecular dynamics revealed that BBR could stably bind to four of the ten proteins, namely 3-phosphoinositide-dependent protein kinase 1 (PDK1), glucocorticoid receptor (GR), p38 mitogen-activated protein kinase (p38) and dihydroorotate dehydrogenase (DHODH). Cellular experiments showed that BBR inhibited cell proliferation, increased the phosphorylation of GR and p38, and inhibited the activity of DHODH in A375 human melanoma cells. CONCLUSIONS: These findings suggest that p38, GR and DHODH are potentially involved in the anti-melanoma action of BBR. This study provided a chemical and pharmacological justification for the clinical use of BBR-containing herbs in melanoma treatment.
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Antineoplásicos/farmacologia , Berberina/farmacologia , Melanoma/metabolismo , Antineoplásicos/uso terapêutico , Berberina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Di-Hidro-Orotato Desidrogenase , Humanos , Melanoma/tratamento farmacológico , Simulação de Acoplamento Molecular , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , Receptores de Glucocorticoides/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Tazarotene-induced gene 3 (TIG3) was first characterized in tazarotene-treated human keratinocytes and identified as a retinoic acid responder gene, an important mediator of antitumor effects by retinoids. In this study, we aim to investigate the inhibitory effect of TIG3 on the growth of liver cancer and explore its underlying mechanism. Human hepatocellular carcinoma (HCC) Hep3B cells were transfected with plasmid GV141 carrying full-length TIG3 complementary DNA (cDNA). The effects of TIG3 on cell proliferation, apoptosis, and migration were determined in vitro. The suppressor effect of TIG3 on tumor growth was evaluated in vivo in a nude mouse HCC model. We observed that TIG3 expression is decreased in the Hep3B cell line as well as primary HCC tumors, and TIG3 expression inversely correlates with Ki-67 expression. Overexpression of TIG3 suppresses tumor growth in HCC both in vitro and in vivo via ERK1/2 inhibition by promoting apoptosis and inhibiting proliferation and migration. These findings identify TIG3 as an attractive therapeutic target for HCC.
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Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases/fisiologia , Receptores do Ácido Retinoico/genética , Adulto , Idoso , Animais , Apoptose/genética , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Citometria de Fluxo , Xenoenxertos , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Confocal , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , TransfecçãoRESUMO
An allothermal biomass gasification system using biomass micron fuel (BMF) as external heat source was developed. In this system, heat supplied to gasifier was generated from combustion of BMF. Biomass feedstock was gasified with steam and then tar in the produced gas was decomposed in a catalytic bed with NiO/γ-Al(2)O(3) catalyst. Finally the production gas was employed as a substitute for civil fuel gas. An overall energy analysis of the system was also investigated. The results showed that the lower heating value of the product gas reached more than 12 MJ/Nm(3). The combusted BMF accounted for 26.8% of the total energy input. Allothermal gasification based on the substituted BMF for conventional energy was an efficient and economical technology to obtain bioenergy.
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Biomassa , Gases/química , Temperatura Alta , Óxido de Alumínio/química , Catálise , Níquel/químicaRESUMO
Sonic hedgehog (SHH) plays an important role in postnatal tissue repair. The present study tested the hypothesis that impaired SHH pathway results in delayed wound healing by suppressing cutaneous nitric oxide (NO) function in type 1 diabetes. Adult male C57/B6 mice and streptozotocin (STZ)-induced type 1 diabetic mice were used. Although cutaneous SHH and Patched-1 (Ptc-1 encoded by PTCH, PTCH 1) proteins were increased significantly on day 4 after wounding compared with day 0 in normal mice, both were decreased significantly in STZ-induced diabetic mice. Topical application of SHH restored wound healing delay in STZ-induced diabetic mice, with a concomitant augmentation of both cutaneous constitutive nitric oxide synthase (NOS) activity and nitrite level. The effects of SHH on wound healing and cutaneous NO function were markedly inhibited by SHH receptor inhibitor cyclopamine. After 24-h treatment in vitro, SHH (5-20 microg/ml) significantly increased cutaneous endothelial NOS protein expression, NOS activity and NO level in normal mice and STZ-induced diabetic mice in a concentration-dependent manner, an effect that was blunted by cyclopamine and NOS inhibitor N(omega)-nitro-L-arginine methyl ester. The phosphatidylinositol 3-kinase inhibitor LY-294002 significantly blunted the increase of NOS activity and NO level induced by SHH treatment in human umbilican vein endothelial cells. These results demonstrate that the SHH pathway is activated in a normal wound, and its reduction results in impaired NO function and wound healing in diabetes. Strategies aimed at augmenting the endogenous SHH pathway may provide an effective means in ameliorating delayed diabetic wound healing.