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1.
Nano Lett ; 24(30): 9296-9301, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39037306

RESUMEN

The two-dimensional (2D) honeycomb lattice has attracted intensive research interest due to the appearance of Dirac-type band structures as the consequence of two sublattices in the honeycomb structure. Introducing strong spin-orbit coupling (SOC) leads to a gap opening at the Dirac point, transforming the honeycomb lattice into a 2D topological insulator as a platform for the quantum spin Hall effect (QSHE). In this work, we realize a 2D honeycomb-structured film with tellurium, the heaviest nonradioactive element in Group VI, namely, tellurene, via molecular beam epitaxy. We revealed the gap opening of 160 meV at the Dirac point due to the strong SOC in the honeycomb-structured tellurene by angle-resolved photoemission spectroscopy. The topological edge states of tellurene are detected via scanning tunneling microscopy/spectroscopy. These results demonstrate that tellurene is a novel 2D honeycomb lattice with strong SOC, and they unambiguously prove that tellurene is a promising candidate for a room-temperature QSHE system.

2.
BMC Genomics ; 25(1): 704, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030492

RESUMEN

The growth, yield, and seed quality of rapeseed are negatively affected by drought stress. Therefore, it is of great value to understand the molecular mechanism behind this phenomenon. In a previous study, long non-coding RNAs (lncRNAs) were found to play a key role in the response of rapeseed seedlings to drought stress. However, many questions remained unanswered. This study was the first to investigate the expression profile of lncRNAs not only under control and drought treatment, but also under the rehydration treatment. A total of 381 differentially expressed lncRNA and 10,253 differentially expressed mRNAs were identified in the comparison between drought stress and control condition. In the transition from drought stress to rehydration, 477 differentially expressed lncRNAs and 12,543 differentially expressed mRNAs were detected. After identifying the differentially expressed (DE) lncRNAs, the comprehensive lncRNAs-engaged network with the co-expressed mRNAs in leaves under control, drought and rehydration was investigated. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of co-expressed mRNAs identified the most significant pathways related with plant hormones (expecially abscisic acid, auxin, cytokinins, and gibberellins) in the signal transduction. The genes, co-expressed with the most-enriched DE-lncRNAs, were considered as the most effective candidates in the water-loss and water-recovery processes, including protein phosphatase 2 C (PP2C), ABRE-binding factors (ABFs), and SMALL AUXIN UP-REGULATED RNAs (SAURs). In summary, these analyses clearly demonstrated that DE-lncRNAs can act as a regulatory hub in plant-water interaction by controlling phytohormone signaling pathways and provided an alternative way to explore the complex mechanisms of drought tolerance in rapeseed.


Asunto(s)
Sequías , Perfilación de la Expresión Génica , Reguladores del Crecimiento de las Plantas , ARN Largo no Codificante , Plantones , Transducción de Señal , Estrés Fisiológico , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Plantones/genética , Plantones/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas , Brassica napus/genética , Brassica napus/metabolismo , Transcriptoma , Redes Reguladoras de Genes , Brassica rapa/genética , Brassica rapa/metabolismo
3.
J Am Chem Soc ; 146(20): 14318-14327, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38718345

RESUMEN

Multiband convergence has attracted significant interest due to its positive effects on further improving thermoelectric performance. However, the current research mainly focuses on two- or three-band convergence in lead chalcogenides through doping and alloying. Therefore, exploring a new strategy to facilitate more-band convergence has instructive significance and practical value in thermoelectric research. Herein, we first propose a high-entropy strategy to achieve four-band convergence for optimizing thermoelectric performance. Taking high-entropy AgSbPbSnGeTe5 as an example, we found that the emergence of more-band convergence occurs as the configuration entropy increases; in particular, the four-band convergence occurs in high-entropy AgSbPbSnGeTe5. The overlap of multiatom orbitals in the high-entropy sample contributes to the convergence of four valence bands, promoting the improvement of electrical performance. Meanwhile, due to large lattice distortion and disordered atoms, the phonon mean free path is effectively compressed, resulting in low lattice thermal conductivity of high-entropy AgSbPbSnGeTe5. Consequently, AgSbPbSnGeTe5 achieved an intrinsically high ZT value of 1.22 at 673 K, providing a cornerstone for further optimizing thermoelectric performance. For example, by generally optimizing the carrier concentration, a peak ZT value of ∼1.75 at 723 K is achieved. These insights offer a comprehensive understanding of the band structure affected by unique structures of high-entropy materials and also shed useful light on innovation mechanisms and functionalities for future improvement of thermoelectric performance.

4.
Neurochem Res ; 49(1): 212-221, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37702892

RESUMEN

PKM2 is a glycolytic pyruvate kinase isoenzyme, and its role in neurological diseases has been published. However, the role and mechanism of PKM2 in the process of status epilepticus have not been reported. The purpose of this study is to explore the role and mechanism of PKM2 in epilepsy. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to explore the expression of PKM2 in cells. Enzyme-linked immunosorbent assay kits were used to evaluate the level of inflammatory factors. An epilepsy model was established by intraperitoneal injection of lithium chloride in rats. Various behavioural assays were conducted to explore the learning ability and cognitive level of rats. PKM2 expression was upregulated in Mg2+-induced hippocampal neurons. PKM2 inhibition ameliorated Mg2+-induced hippocampal neuronal inflammation and reduced neuronal apoptosis. In addition, PKM2 silencing inhibited the metabolic dysfunction of Mg2+-induced hippocampal neurons. Subsequent experiments showed that the Akt/mTOR pathway and NLRP3 inflammasome are involved in PKM2-mediated neuronal regulation. More importantly, PKM2 inhibition could alleviate status epilepticus in rats. PKM2 inhibition attenuates Mg2+-induced hippocampal neuronal inflammation, apoptosis and metabolic dysfunction and improves the cognitive ability of rats. Therefore, PKM2 may be an important target for epilepsy treatment.


Asunto(s)
Lesiones Encefálicas , Epilepsia , Estado Epiléptico , Ratas , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteínas Proto-Oncogénicas c-akt , Serina-Treonina Quinasas TOR , Inflamación , Estado Epiléptico/inducido químicamente
5.
J Am Chem Soc ; 145(27): 14981-14993, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37382475

RESUMEN

Thermoelectric copper selenides are highly attractive owing to not only their constituent nontoxic, abundant elements but also their ultralow liquid-like lattice thermal conductivity (κlat). For the first time, the promising thermoelectric properties of the new KCu5Se3 are reported herein, showing a high power factor (PF = 9.0 µWcm-1 K-2) and an intrinsically ultralow κlat = 0.48 Wm-1 K-1. The doped K1-xBaxCu5Se3 (x = 0.03) realizes a figure-of-merit ZT = 1.3 at 950 K. The crystallographic structure of KCu5Se3 allows complex lattice dynamics that obey a rare dual-phonon transport model well describing a high scattering rate and an extremely short phonon lifetime that are attributed to interband phonon tunneling, confinement of the transverse acoustic branches, and temperature-dependent anharmonic renormalization, all of which generate an unprecedently high contribution of the diffusive phonons (70% at 300 K). The overall weak chemical bonding feature of KCu5Se3 gives K+ cations a quiescence behavior that further blocks the heat flux transfer. In addition, the valence band edge energy dispersion of KCu5Se3 is quasilinear that allows a large Seebeck coefficient even at high hole concentrations. These in-depth understandings of the ultralow lattice thermal conductivity provide new insights into the property-oriented design and synthesis of advanced complex chalcogenide materials.

6.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37511002

RESUMEN

Plant Cysteine Oxidase (PCO) is a plant O2-sensing enzyme catalyzing the oxidation of cysteine to Cys-sulfinic acid at the N-termini of target proteins. To better understand the Brassica napus PCO gene family, PCO genes in B. napus and related species were analyzed. In this study, 20, 7 and 8 PCO genes were identified in Brassica napus, Brassica rapa and Brassica oleracea, respectively. According to phylogenetic analysis, the PCOs were divided into five groups: PCO1, PCO2, PCO3, PCO4 and PCO5. Gene organization and motif distribution analysis suggested that the PCO gene family was relatively conserved during evolution. According to the public expression data, PCO genes were expressed in different tissues at different developmental stages. Moreover, qRT-PCR data showed that most of the Bna/Bra/BoPCO5 members were expressed in leaves, roots, flowers and siliques, suggesting an important role in both vegetative and reproductive development. Expression of BnaPCO was induced by various abiotic stress, especially waterlogging stress, which was consistent with the result of cis-element analysis. In this study, the PCO gene family of Brassicaceae was analyzed for the first time, which contributes to a comprehensive understanding of the origin and evolution of PCO genes in Brassicaceae and the function of BnaPCO in abiotic stress responses.


Asunto(s)
Brassica napus , Brassica napus/metabolismo , Cisteína-Dioxigenasa/genética , Cisteína-Dioxigenasa/metabolismo , Filogenia , Genes de Plantas , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Familia de Multigenes , Genoma de Planta
7.
Phys Rev Lett ; 129(14): 146401, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36240409

RESUMEN

Topological materials have broad application prospects in quantum computing and spintronic devices. Among them, dual topological materials with low dimensionality provide an excellent platform for manipulating various topological states and generating highly conductive spin currents. However, direct observation of their topological surface states still lacks. Here, we reveal the coexistence of the strong and weak topological phases in a quasi-one-dimensional material, TaNiTe_{5}, by spin- and angle- resolved photoemission spectroscopy. The surface states protected by weak topological order forms Dirac-node arcs in the vicinity of the Fermi energy, providing the opportunity to develop spintronics devices with high carrier density that is tunable by bias voltage.

8.
J Appl Microbiol ; 132(3): 2144-2156, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34797022

RESUMEN

AIMS: Phospholipase C (PLC) is a hydrolase involved in signal transduction in eukaryotic cells. This study aimed to understand the function of PLC in the nematode-trapping fungus Arthrobotrys oligospora. METHODS AND RESULTS: Orthologous PLC (AoPLC2) of A. oligospora was functionally analysed using gene disruption and multi-phenotypic analysis. Disrupting Aoplc2 caused a deformation of partial hyphal cells (about 10%) and conidia (about 50%), decreased the number of nuclei in both conidia and hyphal cells, and increased the accumulation of lipid droplets. Meanwhile, the sporulation-related genes fluG and abaA were downregulated in ΔAoplc2 mutants than in the wild-type strain. Moreover, ΔAoplc2 mutants were more sensitive to osmotic stressors. Importantly, the number of traps, electron-dense bodies in traps, and nematicidal activity of ΔAoplc2 mutants were reduced, and the shape of the traps was deformed. In addition, AoPLC2 was involved in the biosynthesis of secondary metabolites in A. oligospora. CONCLUSIONS: AoPLC2 plays an important role in the development of hyphae, spores, and cell nuclei, responses to stress, formation of traps, and predation of nematodes in A. oligospora. SIGNIFICANCE AND IMPACT OF STUDY: This study reveals the various functions of phospholipase C and elucidates the regulation of trap morphogenesis in nematode-trapping fungi.


Asunto(s)
Ascomicetos , Nematodos , Fosfolipasas de Tipo C , Animales , Ascomicetos/enzimología , Ascomicetos/genética , Morfogénesis , Nematodos/microbiología , Fosfolipasas de Tipo C/genética , Fosfolipasas de Tipo C/metabolismo , Virulencia/genética
9.
Neoplasma ; 69(3): 504-515, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35103479

RESUMEN

Bone is a common metastatic site of malignancies, caused by the complex interaction between tumor cells and the bone microenvironment. The complicated procedure covers multiple targets for therapeutic strategies against bone metastasis. At the present, only bisphosphonates and denosumab are currently approved for the prevention of skeletal-related events. But it is still ineffective for some patients, and none of them are proven to prolong the overall survival of patients with bone metastasis. Thus, new bone-modifying agents and therapeutic strategies are required. The review aimed to generalize the basic theory of bone metastasis and major put emphasis on the development of fundamental and potential target drugs in the behavior of bone metastasis. The summary of the drug development process helps to provide ideas for finding new and effective treatments for bone metastasis.


Asunto(s)
Neoplasias Óseas , Denosumab , Neoplasias Óseas/secundario , Denosumab/uso terapéutico , Difosfonatos/uso terapéutico , Humanos , Microambiente Tumoral
10.
Int J Mol Sci ; 23(23)2022 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-36499633

RESUMEN

Carbon nanoparticles have potential threats to plant growth and stress tolerance. The polyhydroxy fullerene-fullerol (one of the carbon nanoparticles) could increase biomass accumulation in several plants subjected to drought; however, the underlying molecular and metabolic mechanisms governed by fullerol in improving drought tolerance in Brassica napus remain unclear. In the present study, exogenous fullerol was applied to the leaves of B. napus seedlings under drought conditions. The results of transcriptomic and metabolomic analyses revealed changes in the molecular and metabolic profiles of B. napus. The differentially expressed genes and the differentially accumulated metabolites, induced by drought or fullerol treatment, were mainly enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to carbohydrate metabolism (e.g., "carbon metabolism" and "galactose metabolism"), amino acid metabolism (e.g., "biosynthesis of amino acids" and "arginine and proline metabolism"), and secondary metabolite metabolism (e.g., "biosynthesis of secondary metabolites"). For carbohydrate metabolism, the accumulation of oligosaccharides (e.g., sucrose) was decreased, whereas that of monosaccharides (e.g., mannose and myo-inositol) was increased by drought. With regard to amino acid metabolism, under drought stress, the accumulation of amino acids such as phenylalanine and tryptophan decreased, whereas that of glutamate and proline increased. Further, for secondary metabolite metabolism, B. napus subjected to soil drying showed a reduction in phenolics and flavonoids, such as hyperoside and trans-3-coumaric acid. However, the accumulation of carbohydrates was almost unchanged in fullerol-treated B. napus subjected to drought. When exposed to water shortage, the accumulation of amino acids, such as proline, was decreased upon fullerol treatment. However, that of phenolics and flavonoids, such as luteolin and trans-3-coumaric acid, was enhanced. Our findings suggest that fullerol can alleviate the inhibitory effects of drought on phenolics and flavonoids to enhance drought tolerance in B. napus.


Asunto(s)
Brassica napus , Brassica napus/metabolismo , Resistencia a la Sequía , Estrés Fisiológico/genética , Sequías , Prolina/metabolismo , Carbono/metabolismo , Regulación de la Expresión Génica de las Plantas
11.
Angew Chem Int Ed Engl ; 61(35): e202208216, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-35817753

RESUMEN

We report a Zintl phase thermoelectric material, coarse grain-In0.99 Ga0.01 Te, achieving a ZT peak of 1.2 at 648 K and an average ZT=0.8 in 300-650 K, which outperforms all the known InTe-based materials to date. The synergistic optimization of electronic property and phonon transport are achieved by the purification of grain boundary scattering, together with the Ga-doping-induced weak phonon-electron coupling, which enhances the carrier mobility and carrier concentration simultaneously and consequently gives a remarkably increased power factor of 8.9 µW cm-1 K-2 . The DFT phonon calculations indicate the dopant reduces the deformation potential coefficient and induces the lattice shrink, which reduces significantly the acoustic cutoff frequency, and enhances the scattering phase space. Moreover, the bonding hierarchy leads to the dense intragranular dislocation arrays, which suppresses the lattice thermal conductivity further and induces an ultralow lattice thermal conductivity (0.21 Wm-1 K-1 ).

12.
J Am Chem Soc ; 143(44): 18490-18501, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34705460

RESUMEN

Crystalline solids that exhibit inherently low lattice thermal conductivity (κlat) have attracted a great deal of attention because they offer the only independent control for pursuing a high thermoelectric figure of merit (ZT). Herein, we report the successful preparation of CsCu4Q3 (Q = S (compound 1), Se (compound 2)) with the aid of a safe and facile boron-chalcogen method. The single-crystal diffraction data confirm the P4/mmm hierarchical structures built up by the mixed-valence [(Cu+)4(Q2-)2](Q-) double anti-CaF2 layer and the NaCl-type Cs+ sublattice involving multiple bonding interactions. The electron-poor compound CsCu4Q3 features Cu-Q antibonding states around EF that facilitates a high σ value of 3100 S/cm in 2 at 323 K. Significantly, the ultralow κlat value of 2, 0.20 W/m/K at 650 K (70% lower than that of Cu2Se), is mainly driven by the vibrational coupling of the rigid double anti-CaF2 layer and the soft NaCl-type sublattice. The hierarchical structure increases the bond multiplicity, which eventually leads to a large phonon anharmonicity, as evidenced by the effective scattering of the low-lying optical phonons to the heat-carrying acoustic phonons. Consequently, the acoustic phonon frequency in 2 drops sharply from 118 cm-1 (of Cu2Se) to 48 cm-1. In addition, the elastic properties indicate that the hierarchical structure largely inhibits the transverse phonon modes, leading to a sound velocity (1571 m/s) and a Debye temperature (189 K) lower than those of Cu2Se (2320 m/s; 292 K).

13.
J Am Chem Soc ; 142(11): 5293-5303, 2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32118412

RESUMEN

The discovery of low-cost, less toxic, and earth-abundant thermoelectric materials is a great challenge. Herein, with the aid of a unique and safe boron-chalcogen method, we discover the new tetragonal α-CsCu5Se3, featuring a previously unrecognized structure in the ternary family of Cs/Cu/Se. The structure is constructed by a Chinese-knot-like Cu8Se8 building unit that is further linked into a 3D network. α-CsCu5Se3 exhibits thermal stability that is superior to that of the recently established thermoelectric materials Cu2-xSe and CsAg5Te3 suffering unfavorable phase transitions. Distinct from the liquidlike migration in Cu2-xSe, α-CsCu5Se3 obeys a typical crystalline solid thermal transport behavior dominated by Umklapp scattering. In compariosn to the isostructural CsAg5Te3, α-CsCu5Se3 shows a 30% volume decrease that leads to stronger orbital overlapping that markedly decreases the band effective mass (m*). With a smaller m* and a softer Cu-Se bond, α-CsCu5Se3 eventually realizes a 200% increase in the power factor (8.17 µW/(cm K2), the highest among the copper-rich alkali-metal chalcogenides) and a figure of merit (ZT) of 1.03 at 980 K. Further, the doping in α-Cs(Cu0.96Sb0.04)5Se3 boosts the lattice anharmonicity by the lone pairs that, via intensifying the Umklapp scattering and slowing the phonon velocity, ensures a low lattice thermal conductivity (0.40 W/(m K)), and finally leads to a ZTmax value of 1.30 at 980 K. Our discovery represents a step toward low-cost, earth-abundant, and high-performance chalcogenide materials that will shed useful light on future exploration in the related fields.

14.
Inorg Chem ; 58(2): 1371-1376, 2019 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-30620570

RESUMEN

Cu2S, featuring low cost, nontoxicity, and earth abundance, has been recently recognized as a high efficiency thermoelectric (TE) material. However, before reaching the maximum of the figure of merit ( ZT), Cu2S undergoes three phase transformations starting at 370 K, which give rise to severe problems, such as possible decomposition and low reliability. Herein, we discover CsCu5S3 with phase transformation at 823 K, which is significantly higher than the 370 K value of Cu2S. Single crystal diffraction data reveal that its two phases are constructed by the same Cu4S4 columnar building unit via propagating either at the opposite sides into a layered o-CsCu5S3, or at the four apexes into a 3D t-CsCu5S3, respectively. Interestingly, the o-to- t transformation is quick, but the reverse one is relatively slow. Theoretical studies reveal that the Cu4S4 column exhibits not only the most condensed atomic aggregation ( Dcolumn) but also the lightest effective mass ( m*), along which higher σ is realized. More interestingly, both phases exhibit remarkable ZT enhancements, 0.46 at 800 K for o-CsCu5S3, and 0.56 at 875 K for t-CsCu5S3, which are 170% and 175% that of Cu2S at the same temperature.

15.
Nanotechnology ; 30(7): 075604, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30523991

RESUMEN

'Targeting peptides' have demonstrated their value in diagnostic imaging and therapy and novel peptide probes specific to cervical cancer were developed. In the M13KE phage dodecapeptide (12-mer) peptide library, the phage clone S7 showed the best binding to the cancer cells as confirmed by immunofluorescence and flow cytometry assays, and was selected for continued studies. Its binding peptide, CSP3, was synthesized from the sequence of S7's 12-mer at the N-terminus of the minor coat protein pIII of this M13KE phage vector. The peptide's binding was analyzed by the same assays used for S7. It was also assessed using competitive inhibition and binding to a tissue chip. The results demonstrated that the CSP3 peptide bound to cervical carcinoma cells with high sensitivity and specificity. The positive results indicated that the peptide CSP3, conjugated with nanomaterials and chemotherapeutics, may be developed as a targeting vehicle for therapeutic drug delivery against cervical cancer, especially cervical cancer with multiple drug resistance. For this aim, we prepared a CSP3 conjugated liposome drug delivery system containing doxorubicin (DOX) and microRNA101 (miR101) expression plasmids (CSP3-Lipo-DOX-miR101), and the primary result showed that the system demonstrated significantly enhanced cytotoxicity to SiHa cells and DOX resistant SiHa cells, SiHa/ADR. Our results showed that CSP3 is a cervical cancer targeting 12aa peptide with high specificity and sensitivity, and the CSP3 conjugated drug delivery system, CSP3-Lipo-DOX-miR101 has promising potential for development as an efficient drug system for the therapy of cervical cancer.


Asunto(s)
Doxorrubicina/análogos & derivados , MicroARNs/farmacología , Péptidos/metabolismo , Neoplasias del Cuello Uterino/metabolismo , Adulto , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Femenino , Humanos , MicroARNs/química , Persona de Mediana Edad , Biblioteca de Péptidos , Péptidos/química , Péptidos/aislamiento & purificación , Polietilenglicoles/química , Polietilenglicoles/farmacología , Neoplasias del Cuello Uterino/terapia
16.
Appl Microbiol Biotechnol ; 103(2): 819-832, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30417308

RESUMEN

Ca2+/calmodulin-dependent protein kinases (CaMKs) are unique second-messenger molecules that impact almost all cellular processes in eukaryotes. In this study, five genes encoding different CaMKs were characterized in the nematode-trapping fungus Arthrobotrys oligospora. These CaMKs, which were retrieved from the A. oligospora genome according to their orthologs in fungi such as Aspergillus nidulans and Neurospora crassa, were expressed at a low level in vitro during mycelial growth stages. Five deletion mutants corresponding to these CaMKs led to growth defects in different media and increased sensitivity to several environmental stresses, including H2O2, menadione, SDS, and Congo red; they also reduced the ability to produce conidia and traps, thus causing a deficiency in nematicidal ability as well. In addition, the transcriptional levels of several typical sporulation-related genes, such as MedA, VelB, and VeA, were down-regulated in all ΔCaMK mutants compared with the wild-type (WT) strain. Moreover, these mutants exhibited hypersensitivity to heat shock and ultraviolet-radiation stresses compared with the WT strain. These results suggest that the five CaMKs in A. oligospora are involved in regulating multiple cellular processes, such as growth, environmental stress tolerance, conidiation, trap formation, and virulence.


Asunto(s)
Ascomicetos/enzimología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Animales , Ascomicetos/crecimiento & desarrollo , Biología Computacional , Eliminación de Gen , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Micelio/enzimología , Micelio/crecimiento & desarrollo , Nematodos/microbiología , Estrés Fisiológico
17.
Fungal Genet Biol ; 116: 42-50, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29702229

RESUMEN

Mitogen-activated protein (MAP) kinase Slt2 is a key player in the cell-wall integrity pathway of budding yeast. In this study, we functionally characterized Slt2 orthologs AoSlt2 and MhSlt2 from the nematode-trapping fungi Arthrobotrys oligospora and Monacrosporium haptotylum, respectively. We found that disruption of AoSlt2 and MhSlt2 led to reduced mycelial growth, increased sensitivity to environmental stresses such as sodium dodecyl sulfate, Congo red, and H2O2, and an inability to produce conidia and nematode-trapping structures. Real-time polymerase chain reaction-based analyses showed that the transcription of sporulation-related (AbaA, Sep2, and MedA) and cell wall synthesis-related (Chs, Glu, and Gfpa) genes was down-regulated in the mutants compared with the wild-type strains. Moreover, the mutant strains showed reduced extracellular proteolytic activity and decreased transcription of three homologous serine protease-encoding genes. These results show for the first time that MAP kinase Slt2 orthologs play similar roles in regulating mycelial growth, conidiation, trap formation, stress resistance, and pathogenicity in the divergent nematode-trapping fungal species A. oligospora and M. haptotylum.


Asunto(s)
Ascomicetos/enzimología , Proteínas Quinasas Activadas por Mitógenos/fisiología , Nematodos/microbiología , Animales , Ascomicetos/crecimiento & desarrollo , Ascomicetos/patogenicidad , Micelio/crecimiento & desarrollo , Estrés Fisiológico , Virulencia
18.
Appl Microbiol Biotechnol ; 102(10): 4601-4613, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29616315

RESUMEN

Rab GTPases are the largest group of the small GTPases family, which play a pivotal role in the secretion of proteins. Arthrobotrys oligospora is a representative nematode-trapping fungus that can produce adhesive networks to capture nematodes. In this study, the roles of two Rab GTPases AoRab-7A and AoRab-2 were characterized by gene knockout in the fungus A. oligospora. The disruption of AoRab-7A hindered the mycelial growth in different media, the conidiation of ΔAoRab-7A transformants was almost abolished, and the transcription of four sporulation-related genes (AbaA, FluG, Hyp1, and VosA) was downregulated compared to the wild-type strain (WT). Furthermore, the tolerance of the ΔAoRab-7A mutants to sodium dodecyl sulfate (SDS) and H2O2 was also significantly reduced compared to the WT, and the transcription of several genes related to environmental resistance, such as genes for catalase and trehalose synthase, was downregulated. Similarly, the extracellular proteolytic activity was decreased. Importantly, the ΔAoRab-7A mutants were unable to produce traps and capture nematodes. However, the disruption of gene AoRab-2 only affected the conidiation slightly but non-significantly, while other phenotypic traits were unaffected. Moreover, the gene AoRab-7A was also involved in the autophagy induced by nitrogen deprivation in A. oligospora. Our results revealed for the first time that the Rab GTPases are involved in the regulation of mycelial growth, conidiation, trap formation, stress resistance, and pathogenicity in the nematode-trapping fungus A. oligospora.


Asunto(s)
Ascomicetos/genética , Ascomicetos/metabolismo , Estrés Fisiológico/genética , Virulencia/genética , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo , Animales , Ascomicetos/efectos de los fármacos , Ascomicetos/patogenicidad , Peróxido de Hidrógeno/toxicidad , Nematodos/microbiología , Dodecil Sulfato de Sodio/toxicidad
19.
Biotechnol Lett ; 39(10): 1463-1469, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28634746

RESUMEN

OBJECTIVES: To screen and identify the probe markers specifically binding to human cervical cancer, a phage-displayed 12-mer peptide library was used for biopanning of SiHa cells. RESULTS: After four rounds of whole-cell subtraction biopanning, the phage recovery was 21-fold higher (from 3.9 × 10-5 to 8.3 × 10-4) than that of the first round, and specific phage clones were significantly enriched. 57 randomly selected phage clones were tested by ELISA, and 36 phage clones were identified as positive clones. After sequencing of positive clones, six different peptide sequences were obtained and CSP3 showed best affinity and specificity to SiHa cells via immunofluorescence assay. CONCLUSIONS: Peptide, CSP3, bound to SiHa cells specifically and sensitively. It may be a potential candidate for molecular imaging detection and targeting therapy of cervical cancer.


Asunto(s)
Péptidos/metabolismo , Análisis de Secuencia de Proteína/métodos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/metabolismo , Células CACO-2 , Línea Celular Tumoral , Detección Precoz del Cáncer , Femenino , Humanos , Células MCF-7 , Imagen Molecular , Terapia Molecular Dirigida , Biblioteca de Péptidos , Péptidos/química , Neoplasias del Cuello Uterino/tratamiento farmacológico
20.
Mol Nutr Food Res ; 68(8): e2300643, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38600887

RESUMEN

SCOPE: Polyphenols are the major active substances in red jujube fruit, and their anti-inflammatory and antioxidant activities suggest their potential utility in the prevention of ulcerative colitis (UC). METHODS AND RESULTS: In this study, the effect of polyphenol extracts from red jujube (Ziziphus jujuba Mill. "Junzao") (PERJ) on the dextron sulfate sodium (DSS)-induced UC mice is investigated. The result shows that PERJ effectively improves clinical symptoms, including food and water intake, the disease activity insex (DAI) and spleen index, and routine blood levels, and alleviates the shortening of the colon, in mice with DSS-induced UC. Meanwhile, PERJ remarkably decreases the expression of proinflammatory factors. Moreover, PERJ repairs intestinal barrier damage by increasing the expression level of mucin 2 and mucin 3, and the result is also confirmed in the histological assessment. Besides, the expression levels of Nod-like receptor family pyrin domain-containing 3 (NLRP3) and mitogen-activated protein kinase cascade (MAPKs) signaling pathway-related proteins are inhibited by the PERJ administration. Finally, 16S rRNA sequencing analyses reveal that PERJ reverses intestinal microbiota dysbiosis by enhancing the abundance of Firmicutes and decreasing that of Proteobacteria and Bacteroidetes. CONCLUSION: PERJ probably inhibits the development of UC by suppressing the NLRP3 and MAPKs signaling pathways and regulating gut microbiota homeostasis, and can be considered as a potential resource for preventing UC.


Asunto(s)
Colitis Ulcerosa , Microbioma Gastrointestinal , Sistema de Señalización de MAP Quinasas , Extractos Vegetales , Ziziphus , Animales , Masculino , Ratones , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Sulfato de Dextran , Microbioma Gastrointestinal/efectos de los fármacos , Homeostasis/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Extractos Vegetales/farmacología , Polifenoles/farmacología , Ziziphus/química
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