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1.
Appl Opt ; 60(25): 7775-7783, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34613250

RESUMEN

A design method and corresponding fabrication procedures are proposed for a dual frusto-conical reflector of a downlight luminaire. The profile of the dual frusto-conical reflector consists of two flat-slant reflective surfaces with slightly different slopes. The optimum dual frusto-conical reflector can be obtained with the proposed design method. The finished product of the dual frusto-conical reflector is fabricated by a 3D printer and followed by surface polishing and reflection paint spraying. The measurement results show that luminaires exhibited 70% optimum illuminance confined within an illumination area of 1.8m2, and the optimum illumination intensity is at 252 lux. The optimum efficiency of the proposed luminaire can reach 158 lm/W for normal-white light-emitting diode (LED) and 119 lm/W for warm-white LED, respectively.

2.
Hereditas ; 158(1): 28, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34384501

RESUMEN

BACKGROUND: The life cycle of Taenia solium is characterized by different stages of development, requiring various kinds of hosts that can appropriately harbor the eggs (proglottids), the oncospheres, the larvae and the adults. Similar to other metazoan pathogens, T. solium undergoes transcriptional and developmental regulation via epigenetics during its complex lifecycle and host interactions. RESULT: In the present study, we integrated whole-genome bisulfite sequencing and RNA-seq technologies to characterize the genome-wide DNA methylation and its effect on transcription of Cysticercus cellulosae of T. solium. We confirm that the T. solium genome in the cysticercus stage is epigenetically modified by DNA methylation in a pattern similar to that of other invertebrate genomes, i.e., sparsely or moderately methylated. We also observed an enrichment of non-CpG methylation in defined genetic elements of the T. solium genome. Furthermore, an integrative analysis of both the transcriptome and the DNA methylome indicated a strong correlation between these two datasets, suggesting that gene expression might be tightly regulated by DNA methylation. Importantly, our data suggested that DNA methylation might play an important role in repressing key parasitism-related genes, including genes encoding excretion-secretion proteins, thereby raising the possibility of targeting DNA methylation processes as a useful strategy in therapeutics of cysticercosis.


Asunto(s)
Metilación de ADN , Genoma de los Helmintos , Taenia solium/genética , Animales , Epigenómica , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , RNA-Seq , Secuenciación Completa del Genoma
3.
BMC Plant Biol ; 18(1): 268, 2018 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-30400867

RESUMEN

BACKGROUND: Cucumbers (Cucumis sativus) are known for their plasticity in sex expression. DNA methylation status determines gene activity but is susceptible to environmental condition changes. Thus, DNA methylation-based epigenetic regulation may at least partially account for the instability of cucumber sex expression. Do temperature and photoperiod that are the two most important environmental factors have equal effect on cucumber sex expression by similar epigenetic regulation mechanism? To answer this question, we did a two-factor experiment of temperature and photoperiod and generated methylome and transcriptome data from cucumber shoot apices. RESULTS: The seasonal change in the femaleness of a cucumber core germplasm collection was investigated over five consecutive years. As a result, 71.3% of the 359 cucumber accessions significantly decreased their femaleness in early autumn when compared with spring. High temperature and long-day photoperiod treatments, which mimic early autumn conditions, are both unfavorable for female flower formation, and temperature is the predominant factor. High temperatures and long-day treatments both predominantly resulted in hypermethylation compared to demethylation, and temperature effect was decisive. The targeted cytosines shared in high-temperature and long-day photoperiod treatment showed the same change in DNA methylation level. Moreover, differentially expressed TEs (DETs) and the predicted epiregulation sites were clustered across chromosomes, and importantly, these sites were reproducible among different treatments. Essentially, the photoperiod treatment preferentially and significantly influenced flower development processes, while temperature treatment produced stronger responses from phytohormone-pathway-related genes. Cucumber AGAMOUS was likely epicontrolled exclusively by photoperiod while CAULIFLOWER A and CsACO3 were likely epicontrolled by both photoperiod and temperature. CONCLUSIONS: Seasonal change of sex expression is a germplasm-wide phenomenon in cucumbers. High temperature and long-day photoperiod might have the same effect on the methylome via the same mechanism of gene-TE interaction but resulted in different epicontrol sites that account for different mechanisms between temperature- and photoperiod-dependent sex expression changes.


Asunto(s)
Cucumis sativus/genética , Epigénesis Genética/genética , Cucumis sativus/fisiología , Metilación de ADN/genética , Regulación de la Expresión Génica de las Plantas/genética , Fotoperiodo , Proteínas de Plantas/genética , Temperatura , Transcriptoma/genética
4.
Genomics ; 103(2-3): 204-10, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24407023

RESUMEN

The model describing that aberrant CpG island (CGI) methylation leads to repression of tumour suppressor genes in cancers has been influential, but it remains unclear how such aberrancy is induced. Recent studies provided clues indicating that promoter hypermethylation in cancers might be associated with PRC target genes. Here, we used ChIP-BS-seq to examine methylation of the DNA fragments precipitated by the antibodies to both H3K27me3 and H3K4me3 histone modifications. We showed that, for a set of genes highly enriched with H3K27me3 both in cancer and normal cells, CGI promoters were aberrantly hypermethylated only in cancer cells in comparison with normal cells. In contrast, such aberrant CGI hypermethylation in cancer promoters that were deficient of H3K27me3 was not notable. Furthermore, we confirmed that these genes were consistently hypermethylated in TCGA primary cancer cells. These works support the association between H3K27me3 and DNA methylation marks for specific cancer genes and will spur future work on combined histone and DNA methylation that could define cancer's epigenetic abnormalities.


Asunto(s)
Islas de CpG , Metilación de ADN , ADN de Neoplasias , Histonas , Proteínas de Neoplasias , Neoplasias , Regiones Promotoras Genéticas , Análisis de Secuencia de ADN , Línea Celular Tumoral , ADN de Neoplasias/genética , ADN de Neoplasias/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo
5.
Comput Struct Biotechnol J ; 20: 4704-4716, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36147684

RESUMEN

Whole genome bisulfite sequencing (WGBS) is an essential technique for methylome studies. Although a series of tools have been developed to overcome the mapping challenges caused by bisulfite treatment, the latest available tools have not been evaluated on the performance of reads mapping as well as on biological insights in multiple mammals. Herein, based on the real and simulated WGBS data of 14.77 billion reads, we undertook 936 mappings to benchmark and evaluate 14 wildly utilized alignment algorithms from reads mapping to biological interpretation in humans, cattle and pigs: Bwa-meth, BSBolt, BSMAP, Walt, Abismal, Batmeth2, Hisat_3n, Hisat_3n_repeat, Bismark-bwt2-e2e, Bismark-his2, BSSeeker2-bwt, BSSeeker2-soap2, BSSeeker2-bwt2-e2e and BSSeeker2-bwt2-local. Specifically, Bwa-meth, BSBolt, BSMAP, Bismark-bwt2-e2e and Walt exhibited higher uniquely mapped reads, mapped precision, recall and F1 score than other nine alignment algorithms, and the influences of distinct alignment algorithms on the methylomes varied considerably at the numbers and methylation levels of CpG sites, the calling of differentially methylated CpGs (DMCs) and regions (DMRs). Moreover, we reported that BSMAP showed the highest accuracy at the detection of CpG coordinates and methylation levels, the calling of DMCs, DMRs, DMR-related genes and signaling pathways. These results suggested that careful selection of algorithms to profile the genome-wide DNA methylation is required, and our works provided investigators with useful information on the choice of alignment algorithms to effectively improve the DNA methylation detection accuracy in mammals.

6.
BMC Genomics ; 12: 597, 2011 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-22151801

RESUMEN

BACKGROUND: DNA methylation plays important roles in gene regulation during both normal developmental and disease states. In the past decade, a number of methods have been developed and applied to characterize the genome-wide distribution of DNA methylation. Most of these methods endeavored to screen whole genome and turned to be enormously costly and time consuming for studies of the complex mammalian genome. Thus, they are not practical for researchers to study multiple clinical samples in biomarker research. RESULTS: Here, we display a novel strategy that relies on the selective capture of target regions by liquid hybridization followed by bisulfite conversion and deep sequencing, which is referred to as liquid hybridization capture-based bisulfite sequencing (LHC-BS). To estimate this method, we utilized about 2 µg of native genomic DNA from YanHuang (YH) whole blood samples and a mature dendritic cell (mDC) line, respectively, to evaluate their methylation statuses of target regions of exome. The results indicated that the LHC-BS system was able to cover more than 97% of the exome regions and detect their methylation statuses with acceptable allele dropouts. Most of the regions that couldn't provide accurate methylation information were distributed in chromosomes 6 and Y because of multiple mapping to those regions. The accuracy of this strategy was evaluated by pair-wise comparisons using the results from whole genome bisulfite sequencing and validated by bisulfite specific PCR sequencing. CONCLUSIONS: In the present study, we employed a liquid hybridisation capture system to enrich for exon regions and then combined with bisulfite sequencing to examine the methylation statuses for the first time. This technique is highly sensitive and flexible and can be applied to identify differentially methylated regions (DMRs) at specific genomic locations of interest, such as regulatory elements or promoters.


Asunto(s)
Metilación de ADN , Exones , Hibridación de Ácido Nucleico , Sulfitos/metabolismo , Humanos
7.
Brain Behav ; 11(8): e2272, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34196487

RESUMEN

BACKGROUND: Methionine has been proven to inhibit addictive behaviors of cocaine dependence. However, the mechanism of methionine response to cocaine CPP is unknown. Recent evidence highlights piRNAs to regulate genes via a miRNA-like mechanism. Here, next-generation sequencing is used to study mechanism on methionine response to drug-induced behaviors though piRNA. METHODS: l-methionine treatment cocaine CPP animal model was used to do non-coding RNA sequencing. There were four groups to sequence: saline+saline (SS), MET+saline (MS), MET+cocaine (MC), and cocaine+saline. Combining mRNA sequencing data, the network and regulation of piRNA were analyzed with their corresponding mRNA and miRNA. RESULTS: Analysis of the piRNAome reveals that piRNAs inversely regulated their target mRNA genes. KEGG analysis of DE-piRNA target mRNA genes were enriched in Morphine addiction, GABAergic synapse and Cholinergic synapse pathway. Furthermore, four significantly differential expressed genes Cacna2d3, Epha6, Nedd4l, and Vav2 were identified and regulated by piRNAs in the process of l-methionine inhibits cocaine CPP. Thereinto, Vav2 was regulated by multiple DE piRNAs by sharing the common sequence: GTCTCTCCAGCCACCTT. Meanwhile, it was found that piRNA positively regulates miRNA and three genes Bcl3, Il20ra, and Insrr were identified and regulated by piRNA through miRNA. CONCLUSION: The results showed that piRNA negatively regulated target mRNA genes and positively regulated target miRNA genes. Genes located in substance dependence, signal transduction and also nervous functions pathways were identified. When taken together, these data may explain the roles of l-methionine in counteracting the effects of cocaine CPP via piRNAs.


Asunto(s)
Cocaína , Metionina , Animales , Cocaína/farmacología , Secuenciación de Nucleótidos de Alto Rendimiento , Ratones , ARN Mensajero , ARN Interferente Pequeño/genética
8.
Materials (Basel) ; 14(8)2021 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-33920557

RESUMEN

The sustainability of resources is presently a major global concern. Sustainable construction materials can be produced by applying biological waste to engineering. Eggshells, as biological waste, are usually dumped in landfills or discarded. This causes many environmental problems including malodor, noise pollution, and serious waste of resources. To solve these problems, this study combined eggshell waste with bitumen materials for bio-roads construction. This paper investigated the impact of biological waste eggshell powder on the high- and low-temperature characteristics of bitumen materials. Scanning electron microscopy (SEM) revealed the microstructure of eggshell powder. The interaction between eggshell powder and asphalt was analyzed using Fourier transform infrared spectroscopy (FT-IR). The high- and low-temperature characteristics were investigated using conventional performance tests, and dynamic shear rheometer (DSR) and bending beam rheometer (BBR) experiments. These results indicate that eggshell powder (1) has a rough and porous microstructure; (2) has no apparent chemical reaction with asphalt; and (3) improves the consistency, hardness, and high-temperature characteristics. However, it reduces the plastic deformation capacity of asphalt, and the low-temperature crack resistance of asphalt cannot be improved. The research demonstrated that the application of eggshell powder in asphalt is feasible and has long-term resource and environmental advantages.

9.
Front Genet ; 11: 939, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33005170

RESUMEN

Beef is an essential food source in the world. Beef quality, especially tenderness, has a significant impact on consumer satisfaction and industry profit. Many types of research to date have focused on the exploration of physiological and developmental mechanisms of beef tenderness. Still, the role and impact of DNA methylation status on beef tenderness have yet to be elucidated. In this study, we exhaustively analyzed the DNA methylation status in divergent tenderness observed in Angus beef. We characterized the methylation profiles related to beef tenderness and explored methylation distributions on the whole genome. As a result, differentially methylated regions (DMRs) associated with tenderness and toughness of beef were identified. Importantly, we annotated these DMRs on the bovine genome and explored bio-pathways of underlying genes and methylation biomarkers in beef quality. Specifically, we observed that the ATP binding cassette subfamily and myosin-related genes were highly methylated gene sets, and generation of neurons, regulation of GTPase activity, ion transport and anion transport, etc., were the significant pathways related with beef tenderness. Moreover, we explored the relationship between DNA methylation and gene expression in DMRs. Some methylated genes were identified as candidate biomarkers for beef tenderness. These results provide not only novel epigenetic information associated with beef quality but offer more significant insights into meat science, which will further help us explore the mechanism of muscle biology.

10.
Nat Commun ; 11(1): 5061, 2020 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-33033262

RESUMEN

The interplay between the Yamanaka factors (OCT4, SOX2, KLF4 and c-MYC) and transcriptional/epigenetic co-regulators in somatic cell reprogramming is incompletely understood. Here, we demonstrate that the histone H3 lysine 27 trimethylation (H3K27me3) demethylase JMJD3 plays conflicting roles in mouse reprogramming. On one side, JMJD3 induces the pro-senescence factor Ink4a and degrades the pluripotency regulator PHF20 in a reprogramming factor-independent manner. On the other side, JMJD3 is specifically recruited by KLF4 to reduce H3K27me3 at both enhancers and promoters of epithelial and pluripotency genes. JMJD3 also promotes enhancer-promoter looping through the cohesin loading factor NIPBL and ultimately transcriptional elongation. This competition of forces can be shifted towards improved reprogramming by using early passage fibroblasts or boosting JMJD3's catalytic activity with vitamin C. Our work, thus, establishes a multifaceted role for JMJD3, placing it as a key partner of KLF4 and a scaffold that assists chromatin interactions and activates gene transcription.


Asunto(s)
Reprogramación Celular , Histona Demetilasas con Dominio de Jumonji/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Animales , Catálisis , Proliferación Celular , Senescencia Celular , Desmetilación , Elementos de Facilitación Genéticos/genética , Células Epiteliales/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Genoma , Histonas/metabolismo , Factor 4 Similar a Kruppel , Lisina/metabolismo , Ratones , Modelos Biológicos , Regiones Promotoras Genéticas , Activación Transcripcional/genética
11.
Front Physiol ; 9: 1755, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30618784

RESUMEN

Aims/Hypothesis: Transforming growth factor-beta (TGF-ß1) plays an important regulatory role in the progression of chronic kidney failure. Further, damage to kidney glomerular mesangial cells is central to the progression of diabetic nephropathy. The aim of this study was to explore the genetic associations between mRNA, microRNA, and epigenetics in mesangial cells in response to TGF-ß1. Methods: The regulatory effects of TGF-ß1 on mesangial cells were investigated at different molecular levels by treating mesangial cells with TGF-ß1 for 3 days followed by genome-wide miRNA, RNA, DNA methylation, and H3K27me3 expression profiling using next generation sequencing (NGS). Results: Our results provide the first comprehensive, computationally integrated report of RNA-Seq, miRNA-Seq, and epigenomic analyses across all genetic variations, confirming the occurrence of DNA methylation and H3K27me3 in response to TGF-ß1. Our findings show that the expression of KLF7 and Gja4 are involved in TGF-ß1 regulated DNA methylation. Our data also provide evidence of the association between epigenetic changes and the expression of genes closely related to TGF-ß1 regulation. Conclusion: This study has advanced our current knowledge of mechanisms that contribute to the expression of TGF-ß1-regulated genes involved in the pathogenesis of kidney disease. The molecular underpinnings of TGF-ß1 stimulation of kidney cells was determined, thereby providing a robust platform for further target exploration.

12.
Technol Cancer Res Treat ; 14(4): 383-94, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26269607

RESUMEN

DNA methylation plays a significant role in assuring cell identity, thus potentiating its application in molecular classification of cancers in respect to tissue-origins or clinically and etiologically distinct subtypes. In this study, we optimized our liquid hybridization capture-based bisulfite sequencing (LHC-BS) approach on the gene promoter regions of 11 cell lines. Our results indicated that promoter methylomes could not only cluster cancer cell lines with respect to tissue origins but also differentiate cancer subtypes based on CpG island methylator phenotype (CIMP). Promoter-targeted LHC-BS as means for comprehensive screening and classifying cancer cells with promoter methylomes provided a powerful strategy for further complex clinical studies.


Asunto(s)
Análisis por Conglomerados , Regulación Neoplásica de la Expresión Génica , Neoplasias/genética , Hibridación de Ácido Nucleico , Regiones Promotoras Genéticas , Línea Celular Tumoral , Metilación de ADN , Humanos , Análisis de Secuencia de ADN
13.
PLoS One ; 8(5): e64954, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23741434

RESUMEN

The epithelial to mesenchymal transition (EMT) has been well recognized for many decades as an essential early step in the progression of primary tumors towards metastases. Widespread epigenetic reprogramming of DNA and histone modifications tightly regulates gene expression and cellular activity during carcinogenesis, and epigenetic therapy has been developed to design efficient strategies for cancer treatment. As the first oral agent approved for the clinical treatment of cancer, sorafenib has significant inhibitory effects on tumor growth and EMT. However, a detailed understanding of the underlying epigenetic mechanism remains elusive. In this manuscript, we performed a ChIP-seq assay to evaluate the activity of sorafenib on the genome-wide profiling of histone modifications. We demonstrate that sorafenib largely reverses the changes in histone modifications that occur during EMT in A549 alveolar epithelial cells. Sorafenib also significantly reduces the coordinated epigenetic switching of critical EMT-associated genes in accordance with their expression levels. Furthermore, we show that sorafenib potentiates histone acetylation by regulating the expression levels of histone-modifying enzymes. Collectively, these findings provide the first evidence that sorafenib inhibits the EMT process through an epigenetic mechanism, which holds enormous promise for identifying novel epigenetic candidate diagnostic markers and drug targets for the treatment of human malignancies.


Asunto(s)
Células Epiteliales Alveolares/efectos de los fármacos , Células Epiteliales Alveolares/metabolismo , Epigénesis Genética , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Niacinamida/análogos & derivados , Compuestos de Fenilurea/farmacología , Acetilación/efectos de los fármacos , Células Epiteliales Alveolares/patología , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/metabolismo , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Humanos , Niacinamida/farmacología , Sorafenib , Factor de Crecimiento Transformador beta1/farmacología
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