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1.
Nucleic Acids Res ; 52(5): 2711-2723, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38281192

RESUMEN

Class IIa Histone deacetylases (HDACs), including HDAC4, 5, 7 and 9, play key roles in multiple important developmental and differentiation processes. Recent studies have shown that class IIa HDACs exert their transcriptional repressive function by interacting with tissue-specific transcription factors, such as members of the myocyte enhancer factor 2 (MEF2) family of transcription factors. However, the molecular mechanism is not well understood. In this study, we determined the crystal structure of an HDAC4-MEF2A-DNA complex. This complex adopts a dumbbell-shaped overall architecture, with a 2:4:2 stoichiometry of HDAC4, MEF2A and DNA molecules. In the complex, two HDAC4 molecules form a dimer through the interaction of their glutamine-rich domain (GRD) to form the stem of the 'dumbbell'; while two MEF2A dimers and their cognate DNA molecules are bridged by the HDAC4 dimer. Our structural observations were then validated using biochemical and mutagenesis assays. Further cell-based luciferase reporter gene assays revealed that the dimerization of HDAC4 is crucial in its ability to repress the transcriptional activities of MEF2 proteins. Taken together, our findings not only provide the structural basis for the assembly of the HDAC4-MEF2A-DNA complex but also shed light on the molecular mechanism of HDAC4-mediated long-range gene regulation.


Asunto(s)
ADN , Histona Desacetilasas , Factores de Transcripción MEF2 , Proteínas Represoras , ADN/química , ADN/metabolismo , Regulación de la Expresión Génica , Genes Reporteros , Factores de Transcripción MEF2/química , Factores de Transcripción MEF2/metabolismo , Factores Reguladores Miogénicos/química , Factores Reguladores Miogénicos/genética , Factores Reguladores Miogénicos/metabolismo , Proteínas Represoras/química , Proteínas Represoras/metabolismo , Humanos , Histona Desacetilasas/química , Histona Desacetilasas/metabolismo
2.
Analyst ; 149(3): 859-869, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38167646

RESUMEN

High efficiency, stability, long emission wavelength (NIR-II), and good biocompatibility are crucial for photosensitizers in phototherapy. However, current Food and Drug Administration (FDA)-approved organic fluorophores exhibit poor chemical stability and photostability as well as short emission wavelength, limiting their clinical usage. To address this, we developed Se-IR1100, a novel organic photosensitizer with a photostable and thermostable benzobisthiadiazole (BBTD) backbone. By incorporating selenium as a heavy atom and constructing a D-A-D structure, Se-IR1100 exhibits a maximum fluorescence emission wavelength of 1100 nm. Compared with FDA-approved indocyanine green (ICG), DSPE-PEGylated Se-IR1100 nanoparticles exhibit prominent photostability and long-lasting photothermal effects. Upon 808 nm laser irradiation, Se-IR1100 NPs efficiently convert light energy into heat and reactive oxygen species (ROS), inducing cancer cell death in cellular studies and living organisms while maintaining biocompatibility. With salient photostability and a photothermal conversion rate of 55.37%, Se-IR1100 NPs hold promise as a superior photosensitizer for diagnostic and therapeutic agents in oncology. Overall, we have designed and optimized a multifunctional photosensitizer Se-IR1100 with good biocompatibility that performs NIR-II fluorescence imaging and phototherapy. This dual-strategy method may offer novel approaches for the development of multifunctional probes using dual-strategy or even multi-strategy methods in bioimaging, disease diagnosis, and therapy.


Asunto(s)
Nanopartículas , Neoplasias , Selenio , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Fototerapia/métodos , Verde de Indocianina/toxicidad , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral
3.
Physiol Plant ; 176(2): e14280, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38644527

RESUMEN

Inadequate reference databases in RNA-seq analysis can hinder data utilization and interpretation. In this study, we have successfully constructed a high-quality reference transcript dataset, ZjRTD1.0, for Zoysia japonica, a widely-used turfgrass with exceptional tolerance to various abiotic stress, including low temperatures and salinity. This dataset comprises 113,089 transcripts from 57,143 genes. BUSCO analysis demonstrates exceptional completeness (92.4%) in ZjRTD1.0, with reduced proportions of fragmented (3.3%) and missing (4.3%) orthologs compared to prior datasets. ZjRTD1.0 enables more precise analyses, including transcript quantification and alternative splicing assessments using public datasets, which identified a substantial number of differentially expressed transcripts (DETs) and differential alternative splicing (DAS) events, leading to several novel findings on Z. japonica's responses to abiotic stresses. First, spliceosome gene expression influenced alternative splicing significantly under abiotic stress, with a greater impact observed during low-temperature stress. Then, a significant positive correlation was found between the number of differentially expressed genes (DEGs) encoding protein kinases and the frequency of DAS events, suggesting the role of protein phosphorylation in regulating alternative splicing. Additionally, our results suggest possible involvement of serine/arginine-rich (SR) proteins and heterogeneous nuclear ribonucleoproteins (hnRNPs) in generating inclusion/exclusion isoforms under low-temperature stress. Furthermore, our investigation revealed a significantly enhanced overlap between DEGs and differentially alternatively spliced genes (DASGs) in response to low-temperature stress, suggesting a unique co-regulatory mechanism governing transcription and splicing in the context of low-temperature response. In conclusion, we have proven that ZjRTD1.0 will serve as a reliable and useful resource for future transcriptomic analyses in Z. japonica.


Asunto(s)
Empalme Alternativo , Frío , Poaceae , Empalme Alternativo/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Estrés Fisiológico/genética , Transcriptoma/genética
4.
Plant Mol Biol ; 112(1-2): 47-59, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37097548

RESUMEN

Leucine-rich repeat extensins (LRXs) are required for plant growth and development through affecting cell growth and cell wall formation. LRX gene family can be classified into two categories: predominantly vegetative-expressed LRX and reproductive-expressed PEX. In contrast to the tissue specificity of Arabidopsis PEX genes in reproductive organs, rice OsPEX1 is also highly expressed in roots in addition to reproductive tissue. However, whether and how OsPEX1 affects root growth is unclear. Here, we found that overexpression of OsPEX1 retarded root growth by reducing cell elongation likely caused by an increase of lignin deposition, whereas knockdown of OsPEX1 had an opposite effect on root growth, indicating that OsPEX1 negatively regulated root growth in rice. Further investigation uncovered the existence of a feedback loop between OsPEX1 expression level and GA biosynthesis for proper root growth. This was supported by the facts that exogenous GA3 application downregulated transcript levels of OsPEX1 and lignin-related genes and rescued the root developmental defects of the OsPEX1 overexpression mutant, whereas OsPEX1 overexpression reduced GA level and the expression of GA biosynthesis genes. Moreover, OsPEX1 and GA showed antagonistic action on the lignin biosynthesis in root. OsPEX1 overexpression upregulated transcript levels of lignin-related genes, whereas exogenous GA3 application downregulated their expression. Taken together, this study reveals a possible molecular pathway of OsPEX1mediated regulation of root growth through coordinate modulation of lignin deposition via a negative feedback regulation between OsPEX1 expression and GA biosynthesis.


Asunto(s)
Arabidopsis , Oryza , Giberelinas/farmacología , Giberelinas/metabolismo , Oryza/metabolismo , Lignina/metabolismo , Proteínas/genética , Arabidopsis/genética , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas
5.
Langmuir ; 39(48): 17498-17512, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37983616

RESUMEN

Safe, efficient, and green synthetic energetic combustion catalysts are of great importance for the application of ammonium perchlorate (AP) in solid propellants. In this study, a novel, simple, efficient, and green electrochemical method for synthesizing energetic combustion catalysts was designed and implemented to successfully synthesize Co(BODN)·9H2O (BODN = [2,2'-bi{1,3,4-oxadiazole}]-5,5'-dinitramide), a novel energetic combustion catalyst. The target products were characterized via single-crystal X-ray diffraction, powder X-ray diffraction, Fourier transform infrared spectroscopy, optical microscopy, scanning electron microscopy, differential scanning calorimetry, and thermogravimetric analysis. Results reveal that Co(BODN)·9H2O crystallizes in the triclinic P1̅ space group and has a density of 1.836 g cm-3. The size of the Co(BODN)·9H2O crystal increases gradually with the increase in the reaction current and the prolongation of the reaction time, respectively. However, the change in reaction current and time does not affect the crystal form. In addition, with the increase in Co(BODN)·9H2O content, the peak temperature of high-temperature decomposition (HTD) and apparent activation energy of AP/Co(BODN)·9H2O gradually decrease, and the heat release during thermal decomposition gradually increases. The HTD peak temperature and apparent activation energy of AP/Co(BODN) 9H2O (10%) decrease by 97.9 °C and 94.2 kJ·mol-1, respectively, compared with those of pure AP, and the heat release during thermal decomposition increases by 1613 J·g-1. Furthermore, compared with those of the propellant containing pure AP, the burning rate and flame temperature of the propellant containing AP/Co(BODN)·9H2O (10%) increase by 8.15 mm s-1 and 458.44 °C, respectively. Real-time Fourier transform infrared spectroscopy reveals that CoO catalyzes the thermal decomposition of AP mainly by promoting electron transfer to accelerate the oxidation of NH3 and the conversion of N2O to NO. In brief, this work provides new insights into synthesizing energetic combustion catalysts. Moreover, Co(BODN)·9H2O synthesized through the electrochemical method exhibits considerable application prospects for improving the thermal and energy performance of AP and the combustion performance of propellants.

6.
PLoS Genet ; 15(7): e1008267, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31291251

RESUMEN

Increasing seed oil content is one of the most important breeding goals for soybean due to a high global demand for edible vegetable oil. However, genetic improvement of seed oil content has been difficult in soybean because of the complexity of oil metabolism. Determining the major variants and molecular mechanisms conferring oil accumulation is critical for substantial oil enhancement in soybean and other oilseed crops. In this study, we evaluated the seed oil contents of 219 diverse soybean accessions across six different environments and dissected the underlying mechanism using a high-resolution genome-wide association study (GWAS). An environmentally stable quantitative trait locus (QTL), GqOil20, significantly associated with oil content was identified, accounting for 23.70% of the total phenotypic variance of seed oil across multiple environments. Haplotype and expression analyses indicate that an oleosin protein-encoding gene (GmOLEO1), colocated with a leading single nucleotide polymorphism (SNP) from the GWAS, was significantly correlated with seed oil content. GmOLEO1 is predominantly expressed during seed maturation, and GmOLEO1 is localized to accumulated oil bodies (OBs) in maturing seeds. Overexpression of GmOLEO1 significantly enriched smaller OBs and increased seed oil content by 10.6% compared with those of control seeds. A time-course transcriptomics analysis between transgenic and control soybeans indicated that GmOLEO1 positively enhanced oil accumulation by affecting triacylglycerol metabolism. Our results also showed that strong artificial selection had occurred in the promoter region of GmOLEO1, which resulted in its high expression in cultivated soybean relative to wild soybean, leading to increased seed oil accumulation. The GmOLEO1 locus may serve as a direct target for both genetic engineering and selection for soybean oil improvement.


Asunto(s)
Glycine max/crecimiento & desarrollo , Aceites de Plantas/metabolismo , Proteínas de Plantas/genética , Semillas/química , Domesticación , Ingeniería Genética , Estudio de Asociación del Genoma Completo , Haplotipos , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Sitios de Carácter Cuantitativo , Semillas/crecimiento & desarrollo , Glycine max/genética , Glycine max/metabolismo , Triglicéridos/metabolismo
7.
Proc Natl Acad Sci U S A ; 116(35): 17563-17571, 2019 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-31409710

RESUMEN

The Arabidopsis DEMETER (DME) DNA glycosylase demethylates the maternal genome in the central cell prior to fertilization and is essential for seed viability. DME preferentially targets small transposons that flank coding genes, influencing their expression and initiating plant gene imprinting. DME also targets intergenic and heterochromatic regions, but how it is recruited to these differing chromatin landscapes is unknown. The C-terminal half of DME consists of 3 conserved regions required for catalysis in vitro. We show that this catalytic core guides active demethylation at endogenous targets, rescuing dme developmental and genomic hypermethylation phenotypes. However, without the N terminus, heterochromatin demethylation is significantly impeded, and abundant CG-methylated genic sequences are ectopically demethylated. Comparative analysis revealed that the conserved DME N-terminal domains are present only in flowering plants, whereas the domain architecture of DME-like proteins in nonvascular plants mainly resembles the catalytic core, suggesting that it might represent the ancestral form of the 5mC DNA glycosylase found in plant lineages. We propose a bipartite model for DME protein action and suggest that the DME N terminus was acquired late during land plant evolution to improve specificity and facilitate demethylation at heterochromatin targets.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Dominio Catalítico , Desmetilación del ADN , Regulación de la Expresión Génica de las Plantas , N-Glicosil Hidrolasas/metabolismo , Transactivadores/metabolismo , Arabidopsis/clasificación , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Epigénesis Genética , Evolución Molecular , Heterocromatina/genética , Heterocromatina/metabolismo , Modelos Moleculares , N-Glicosil Hidrolasas/química , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Transactivadores/química
8.
Chem Biodivers ; 19(11): e202200531, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36208060

RESUMEN

Cyperus esculentus is cultivated as a crop plant due to its edible and oily tubers (tiger nut). However, little is known about the phytochemicals and bioeffects of the leaves. This study was conducted to identify and quantify the chemical constituents of C. esculentus leaves and evaluate their bioactivities. By liquid chromatography-mass spectrometry, 30 compounds including flavan-3-ols, caffeic acid derivatives, and flavones, were identified from the leaves. The quantitative analysis revealed that gallocatechin (8), procyanidin B1 (15), catechin (16), chlorogenic acid (19), orientin (30), and luteolin 7-O-glucuronide (31) are the major chemical constituents of C. esculentus leaves. The contents of these six chemical constituents in the leaves collected in September in Hohhot, China, reached to 1460.85±7.66, 10178.77±302.65, 1048.35±17.37, 1722.15±26.13, 5318.62±277.16, and 1526.54±11.95 µg, respectively, in one gram of the dried leaves. The leaf extract (CELE) showed strong antioxidant activity in vitro, with compounds 8, 15, and 19 contributing the most. CELE showed significant protection against the agricultural fungicide tebuconazole-induced developmental toxicity and hepatotoxicity in zebrafish.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Cyperus , Fungicidas Industriales , Animales , Cyperus/química , Fungicidas Industriales/toxicidad , Pez Cebra , Antioxidantes/farmacología , Extractos Vegetales/química , Hojas de la Planta/química
9.
Chem Soc Rev ; 50(20): 11227-11248, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34661214

RESUMEN

Despite significant advances, the therapeutic impact of photodynamic therapy is still substantially hampered by the restricted penetration depth of light and the reactive oxygen species (ROS)-mediated toxicity, which is impeded by the shorter effective half-life and radius of ROS produced during treatment. Sonodynamic therapy (SDT), on the other hand, provides unrivalled benefits in deep-seated tumour ablation due to its deep penetration depth and not totally ROS-dependent toxicity, exhibiting enormous preclinical and clinical potential. In this tutorial review, we highlight imaging-guided precise SDT, which allows choosing the best treatment option and monitoring the therapy response in real-time, as well as recent clinical trials based on SDT. Aside from that, the subtle design strategies of sonosensitizers based on tumour environment shaping and rational structure modification, as well as SDT combination treatment (chemotherapy, chemodynamic therapy, photodynamic therapy, photothermal therapy, gas therapy and immunotherapy), aimed at a more effective treatment outcome, are summarized. Finally, we discussed the future of SDT for personalized cancer and other disease treatments.


Asunto(s)
Neoplasias , Fotoquimioterapia , Terapia por Ultrasonido , Biotecnología , Terapia Combinada , Humanos , Neoplasias/tratamiento farmacológico
10.
BMC Genomics ; 22(1): 433, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34107875

RESUMEN

BACKGROUND: Phosphorus (P) is essential for plant growth and development, and low-phosphorus (LP) stress is a major factor limiting the growth and yield of soybean. Long noncoding RNAs (lncRNAs) have recently been reported to be key regulators in the responses of plants to stress conditions, but the mechanism through which LP stress mediates the biogenesis of lncRNAs in soybean remains unclear. RESULTS: In this study, to explore the response mechanisms of lncRNAs to LP stress, we used the roots of two representative soybean genotypes that present opposite responses to P deficiency, namely, a P-sensitive genotype (Bogao) and a P-tolerant genotype (NN94156), for the construction of RNA sequencing (RNA-seq) libraries. In total, 4,166 novel lncRNAs, including 525 differentially expressed (DE) lncRNAs, were identified from the two genotypes at different P levels. GO and KEGG analyses indicated that numerous DE lncRNAs might be involved in diverse biological processes related to phosphate, such as lipid metabolic processes, catalytic activity, cell membrane formation, signal transduction, and nitrogen fixation. Moreover, lncRNA-mRNA-miRNA and lncRNA-mRNA networks were constructed, and the results identified several promising lncRNAs that might be highly valuable for further analysis of the mechanism underlying the response of soybean to LP stress. CONCLUSIONS: These results revealed that LP stress can significantly alter the genome-wide profiles of lncRNAs, particularly those of the P-sensitive genotype Bogao. Our findings increase the understanding of and provide new insights into the function of lncRNAs in the responses of soybean to P stress.


Asunto(s)
ARN Largo no Codificante , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genotipo , Fosfatos/metabolismo , ARN Largo no Codificante/genética , Glycine max/genética , Glycine max/metabolismo
11.
J Eukaryot Microbiol ; 68(2): e12839, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33448088

RESUMEN

Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis are common enteric pathogens that are capable of infecting humans and animals. Total of 1,005 fecal samples from captive pet birds were collected from seven locations in Henan Province, China. The results demonstrated that 9.9% (99/1,005) of the captive birds were infected with one of these three pathogens. Enterocytozoon bieneusi was the most prevalent species among the birds (45/1,005, 4.5%) followed by G. duodenalis (33/1,005, 3.3%) and Cryptosporidium spp. (21/1,005, 2.1%). Five Cryptosporidium species were identified, namely, C. baileyi (10), C. galli (5), C. meleagridis (4), C. andersoni (1), and C. parvum (1). Two known E. bieneusi genotypes were identified: Peru 6 (44) was identified in pigeons (34) and European turtle doves (10); whereas, the genotype PtEb I (1) was only identified in a pigeon. Only G. duodenalis assemblage E (33) was identified in some pet birds. To the best of our knowledge, this study is the first to undertake the molecular identification of G. duodenalis in birds in China. The identification of potentially zoonotic species/genotypes of the pathogens suggests that exposure to the excreta of these birds, either directly or via food and water, may pose a threat to human health.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Enterocytozoon , Giardia lamblia , Giardiasis , Microsporidiosis , Animales , Aves , China/epidemiología , Criptosporidiosis/epidemiología , Cryptosporidium/genética , Enterocytozoon/genética , Heces , Genotipo , Giardia lamblia/genética , Giardiasis/veterinaria , Microsporidiosis/epidemiología , Microsporidiosis/veterinaria
12.
Int J Mol Sci ; 21(18)2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957498

RESUMEN

Low-phosphorus (low-P) stress has a significant limiting effect on crop yield and quality. Although the molecular mechanisms of the transcriptional level responsible for the low-P stress response have been studied in detail, the underlying epigenetic mechanisms in gene regulation remain largely unknown. In this study, we evaluated the changes in DNA methylation, gene expression and small interfering RNAs (siRNAs) abundance genome-wide in response to low-P stress in two representative soybean genotypes with different P-efficiencies. The DNA methylation levels were slightly higher under low-P stress in both genotypes. Integrative methylation and transcription analysis suggested a complex regulatory relationship between DNA methylation and gene expression that may be associated with the type, region, and extent of methylation. Association analysis of low-P-induced differential methylation and gene expression showed that transcriptional alterations of a small part of genes were associated with methylation changes. Dynamic methylation alterations in transposable element (TE) regions in the CHH methylation context correspond with changes in the amount of siRNA under low-P conditions, indicating an important role of siRNAs in modulating TE activity by guiding CHH methylation in TE regions. Together, these results could help to elucidate the epigenetic regulation mechanisms governing the responses of plants to abiotic stresses.


Asunto(s)
Metilación de ADN , Glycine max/metabolismo , Fósforo/metabolismo , ARN Interferente Pequeño/metabolismo , Estrés Fisiológico/genética , Elementos Transponibles de ADN/genética , Epigénesis Genética , Epigenómica , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Genoma de Planta , Estudio de Asociación del Genoma Completo , ARN Interferente Pequeño/genética , RNA-Seq , Glycine max/genética
13.
Plant Mol Biol ; 100(1-2): 151-161, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30840202

RESUMEN

KEY MESSAGE: Rice leucine-rich repeat extensin-like protein OsPEX1 mediates the intersection of lignin deposition and plant growth. Lignin, a major structural component of secondary cell wall, is essential for normal plant growth and development. However, the molecular and genetic regulation of lignin biosynthesis is not fully understood in rice. Here we report the identification and characterization of a rice semi-dominant dwarf mutant (pex1) with stiff culm. Molecular and genetic analyses revealed that the pex1 phenotype was caused by ectopic expression of a leucine-rich repeat extension-like gene, OsPEX1. Interestingly, the pex1 mutant showed significantly higher lignin content and increased expression levels of lignin-related genes compared with wild type plants. Conversely, OsPEX1-suppresssed transgenics displayed low lignin content and reduced transcriptional abundance of genes associated with lignin biosynthesis, indicating that the OsPEX1 mediates lignin biosynthesis and/or deposition in rice. When OsPEX1 was ectopically expressed in rice cultivars with tall stature that lacks the allele of semi-dwarf 1, well-known green revolution gene, the resulting transgenic plants displayed reduced height and enhanced lodging resistance. Our study uncovers a causative effect between the expression of OsPEX1 and lignin deposition. Lastly, we demonstrated that modulating OsPEX1 expression could provide a tool for improving rice lodging resistance.


Asunto(s)
Glicoproteínas/metabolismo , Lignina/biosíntesis , Oryza/metabolismo , Desarrollo de la Planta , Proteínas de Plantas/metabolismo , Secuencia de Bases , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Glicoproteínas/genética , Mutación/genética , Oryza/genética , Oryza/fisiología , Fenotipo , Proteínas de Plantas/genética , Tallos de la Planta/metabolismo , Plantas Modificadas Genéticamente
14.
Anticancer Drugs ; 30(8): 803-811, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31419217

RESUMEN

Gastric cancer (GC), one of the most common malignant tumors and the second most common leading cause of cancer-related death worldwide, is a biologically heterogeneous disease accompanied by various genetic and epigenetic alterations. However, the molecular mechanisms underlying this disease are complex and not completely understood. Increasing studies have shown that aberrant microRNA (miRNA) expression is associated with GC tumorigenesis and growth. MiR-1297 has been confirmed to be a cancer suppressor in diverse tumors in humans. However, to date, the function and mechanism of miR-1297 in GC have not been determined. Here, we found that the expression of miR-1297 was significantly reduced in GC tissues or GC cell lines compared with paracarcinoma normal tissue or normal cell lines. Exogenic overexpression of miR-1297 in GC cell lines can inhibit cell proliferation and colony formation and induce apoptosis, and inhibition of miR-1297 in GC cell lines can promote cell proliferation and colony formation, and reduce apoptosis in vitro. We further confirmed that miR-1297 acted as a tumor suppressor through targeting cell division control protein 6 (CDC6) in GC. Moreover, the inverse relationship between miR-1297 and CDC6 was verified in GC cell lines. Our results indicated that miR-1297 is a potent tumor suppressor in GC, and its antiproliferative and gene-regulatory effects are, in part, mediated through its downstream target gene, CDC6. These findings implied that miR-1297 might be used as a novel therapeutic target of GC.


Asunto(s)
Apoptosis , Biomarcadores de Tumor/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Proteínas Nucleares/metabolismo , Neoplasias Gástricas/patología , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Ciclo Celular , Proteínas de Ciclo Celular/genética , Humanos , Proteínas Nucleares/genética , Pronóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirugía , Células Tumorales Cultivadas
15.
Bioorg Med Chem Lett ; 29(17): 2448-2451, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31358467

RESUMEN

To further explore the structure activity relationships (SARs) of our previously discovered antifungal lead compound (1), a series of biphenyl imidazole analogues were designed, synthesized and evaluated for their in vitro antifungal activity. Many of the synthesized compounds showed excellent activity against Candida albicans and Candida tropicalis. Among these compounds, 2-F substituted analogue 12m displayed the most remarkable in vitro activity against C. albicans, C. neoformans, A. fumigatus and fluconazole-resistant C. alb. strains, which is superior or comparable to the activity of the reference drugs fluconazole and itraconazole. Notably, the compound 12m exhibited low inhibition profiles for various human cytochrome P450 isoforms and showed low toxicity to mammalian A549 cells and U87 cells. The SARs and binding mode established in this study will be useful for further lead optimization.


Asunto(s)
Antifúngicos/síntesis química , Diseño de Fármacos , Imidazoles/química , Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Sitios de Unión , Compuestos de Bifenilo/química , Candida albicans/efectos de los fármacos , Dominio Catalítico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Fluconazol/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/metabolismo , Humanos , Imidazoles/farmacología , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Relación Estructura-Actividad
16.
Parasitology ; 146(1): 28-32, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29986775

RESUMEN

To determine the prevalence of Cryptosporidium in dairy cattle in Guangdong Province, South China, 1440 fecal samples were collected from 10 farms and screened for Cryptosporidium with PCR. The overall prevalence of Cryptosporidium was 4.38% (63/1440), and the infection rates in preweaned calves, postweaned calves, heifers and adults were 6.4% (19/297), 6.19% (33/533), 1.48% (4/271) and 2.06% (7/339), respectively. Three Cryptosporidium species, Cryptosporidium andersoni (n = 33), Cryptosporidium bovis (n = 22) and Cryptosporidium ryanae (n = 8) were detected by DNA sequence analysis of the 63 positive samples, and C. andersoni was identified as the most common species on the dairy cattle farms. In preweaned calves, C. bovis was the most prevalent species (9/19, 47.4%). In contrast, C. andersoni was the predominant species (19/33, 57.6%) in postweaned calves and the only species found in heifers and adults. The zoonotic species Cryptosporidium parvum was not detected in this study. Twenty-four C. andersoni isolates were successfully classified into three multilocus sequence typing (MLST) subtypes. MLST subtype A4,A4,A4,A1 was the predominant subtype, and MLST subtype A2,A5,A2,A1, previously found in sheep, was detected in cattle for the first time. A linkage disequilibrium analysis showed that the C. andersoni isolates had a clonal genetic population structure. However, further molecular studies are required to better understand the epidemiology of Cryptosporidium in Guangdong.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Criptosporidiosis/epidemiología , Cryptosporidium/genética , Distribución por Edad , Animales , Secuencia de Bases , Bovinos , Enfermedades de los Bovinos/parasitología , China/epidemiología , Criptosporidiosis/parasitología , Cryptosporidium/clasificación , Cryptosporidium/fisiología , ADN Protozoario/química , ADN Protozoario/aislamiento & purificación , Electroforesis en Gel de Agar/veterinaria , Heces/parasitología , Femenino , Desequilibrio de Ligamiento , Epidemiología Molecular , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Análisis de Regresión
17.
BMC Vet Res ; 15(1): 417, 2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31752852

RESUMEN

BACKGROUND: With worldwide distribution and importance for veterinary medicine, Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi have been found in a wide variety of vertebrate hosts. At present, few available molecular data can be used to understand the features of genetic diversity of these pathogens in areas without or less intensive farming. Dominated by grazing, Tibet is a separate geographic unit in China and yaks are in frequent contact with local herdsmen and necessary for their daily life. Therefore, to investigate the distribution of these pathogens in yaks of Tibet, 577 fecal specimens were screened using nested PCR for the presence and genotypes of the three intestinal pathogens. RESULTS: The overall prevalence of Cryptosporidium spp., G. duodenalis, and E. bieneusi were 1.4% (8/577), 1.7% (10/577), and 5.0% (29/577), respectively. Cryptosporidium andersoni (n = 7) and Cryptosporidium bovis (n = 1) were detected by sequence analysis of the SSU rRNA gene. Genotyping at the SSU rRNA and triosephosphate isomerase genes suggested that all G. duodenalis positive specimens belonged to assemblage E. Sequence analysis of the internal transcribed spacer gene identified six known E. bieneusi genotypes: BEB4 (n = 11), I (n = 6), D (n = 5), J (n = 2), CHC8 (n = 1), and BEB6 (n = 1). One subtype (A5,A4,A2,A1) for C. andersoni and three multilocus genotypes for E. bieneusi were identified by multilocus sequence typing. CONCLUSIONS: We report for the first time the status of three enteric pathogens infection simultaneously for grazing yaks in Tibet. Yaks in our study are likely to impose a low zoonotic risk for humans. The molecular epidemiology data add to our knowledge of the characteristics of distribution and transmission for these pathogens in Tibet and their zoonotic potential and public health significance.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Cryptosporidium/aislamiento & purificación , Enterocytozoon/aislamiento & purificación , Giardia lamblia/aislamiento & purificación , Giardiasis/veterinaria , Microsporidiosis/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , Cryptosporidium/genética , Enterocytozoon/genética , Giardia lamblia/genética , Giardiasis/epidemiología , Giardiasis/parasitología , Microsporidiosis/epidemiología , Microsporidiosis/microbiología , Filogenia , Especificidad de la Especie , Tibet/epidemiología
18.
J Eukaryot Microbiol ; 65(6): 854-859, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29710421

RESUMEN

A total of 321 rabbit fecal samples were collected from 10 farms in the Xinjiang Uyghur Autonomous Region, China. The prevalence of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in the samples was 3.4% (11/321), 1.9% (6/321), and 2.8% (9/321), respectively. Small subunit ribosomal RNA (SSU rRNA) gene sequence analysis identified all 11 Cryptosporidium-positive samples as C. cuniculus. Further subtyping based on the 60-kDaglycoprotein locus (gp60) identified five of the C. cuniculus isolates as subtype VbA24. G. duodenalis genotypes were determined by multilocus sequence typing of the SSU rRNA, triosephosphate isomerase, ß-giardin and glutamate dehydrogenase loci, which confirmed that six G. duodenalis isolates belonged to subtype BIV of assemblage B. Analysis of the internal transcribed spacer region, showed that five, three, and one E. bieneusi isolates belonged to genotypes J, BEB8, and Type IV, respectively. These results suggest that Cryptosporidium spp., G. duodenalis, and E. bieneusi isolates from rabbits in China have zoonotic potential.


Asunto(s)
Cryptosporidium/genética , Enterocytozoon/genética , Genotipo , Giardia lamblia/genética , Conejos/parasitología , Animales , China/epidemiología , Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , Cryptosporidium/clasificación , Cryptosporidium/aislamiento & purificación , Proteínas del Citoesqueleto/genética , ADN Protozoario/genética , Enterocytozoon/clasificación , Enterocytozoon/aislamiento & purificación , Heces/parasitología , Giardia lamblia/clasificación , Giardia lamblia/aislamiento & purificación , Giardiasis/epidemiología , Giardiasis/veterinaria , Glutamato Deshidrogenasa/genética , Microsporidiosis/epidemiología , Microsporidiosis/veterinaria , Tipificación de Secuencias Multilocus , Filogenia , Prevalencia , Proteínas Protozoarias/genética , ARN Ribosómico/genética , Análisis de Secuencia , Triosa-Fosfato Isomerasa/genética , Zoonosis/parasitología
19.
Bioorg Med Chem ; 26(12): 3242-3253, 2018 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-29748145

RESUMEN

To further enhance the anti-Aspergillus efficacy of our previously discovered antifungal lead compound 1, a series of benzoheterocycle analogues were designed, synthesized and evaluated for their in vitro antifungal activity. The most promising compounds 13s and 14a exhibited excellent antifungal activity against C. albicans, C. neoformans, A. fumigatus and fluconazole-resistant C. albicans strains, that was superior or comparable to those of the reference drugs fluconazole and voriconazole. GC-MS analyses suggested that the novel compound 13s might have a similar mechanism to fluconazole by inhibiting fungal lanosterol 14α-demethylase (CYP51). Furthermore, compounds 13s and 14a exhibited low inhibition profiles for various human cytochrome P450 isoforms as well as excellent blood plasma stability.


Asunto(s)
Antifúngicos/síntesis química , Diseño de Fármacos , Proteínas Fúngicas/metabolismo , Esterol 14-Desmetilasa/metabolismo , Triazoles/química , Antifúngicos/química , Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/metabolismo , Sitios de Unión , Candida albicans/efectos de los fármacos , Candida albicans/metabolismo , Dominio Catalítico , Cryptococcus neoformans/efectos de los fármacos , Cryptococcus neoformans/metabolismo , Farmacorresistencia Fúngica/efectos de los fármacos , Estabilidad de Medicamentos , Fluconazol/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Cromatografía de Gases y Espectrometría de Masas , Humanos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Esterol 14-Desmetilasa/química , Esteroles/análisis , Relación Estructura-Actividad , Triazoles/síntesis química , Triazoles/farmacología
20.
Cell Mol Life Sci ; 74(15): 2773-2782, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28314894

RESUMEN

Hedgehog signaling is an evolutionarily conserved pathway which is essential in embryonic and postnatal development as well as adult organ homeostasis. Abnormal regulation of Hedgehog signaling is implicated in many diseases including cancer. Consequently, substantial efforts have made in the past to develop potential therapeutic agents that specifically target the Hedgehog signaling for cancer treatment. Here, we review the therapeutic agents for inhibition of the Hedgehog signaling and their clinical advances in cancer treatment.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Proteínas Hedgehog/metabolismo , Neoplasias/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Antineoplásicos/uso terapéutico , Descubrimiento de Drogas , Proteínas Hedgehog/antagonistas & inhibidores , Humanos , Terapia Molecular Dirigida , Neoplasias/metabolismo , Neoplasias/patología , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Bibliotecas de Moléculas Pequeñas/uso terapéutico
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