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1.
Circulation ; 142(4): 365-379, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32393053

RESUMO

BACKGROUND: Metabolic disorders such as obesity and diabetes mellitus can cause dysfunction of endothelial cells (ECs) and vascular rarefaction in adipose tissues. However, the modulatory role of ECs in adipose tissue function is not fully understood. Other than vascular endothelial growth factor-vascular endothelial growth factor receptor-mediated angiogenic signaling, little is known about the EC-derived signals in adipose tissue regulation. We previously identified Argonaute 1 (AGO1; a key component of microRNA-induced silencing complex) as a crucial regulator in hypoxia-induced angiogenesis. In this study, we intend to determine the AGO1-mediated EC transcriptome, the functional importance of AGO1-regulated endothelial function in vivo, and the relevance to adipose tissue function and obesity. METHODS: We generated and subjected mice with EC-AGO1 deletion (EC-AGO1-knockout [KO]) and their wild-type littermates to a fast food-mimicking, high-fat high-sucrose diet and profiled the metabolic phenotypes. We used crosslinking immunoprecipitation- and RNA-sequencing to identify the AGO1-mediated mechanisms underlying the observed metabolic phenotype of EC-AGO1-KO. We further leveraged cell cultures and mouse models to validate the functional importance of the identified molecular pathway, for which the translational relevance was explored using human endothelium isolated from healthy donors and donors with obesity/type 2 diabetes mellitus. RESULTS: We identified an antiobesity phenotype of EC-AGO1-KO, evident by lower body weight and body fat, improved insulin sensitivity, and enhanced energy expenditure. At the organ level, we observed the most significant phenotype in the subcutaneous and brown adipose tissues of KO mice, with greater vascularity and enhanced browning and thermogenesis. Mechanistically, EC-AGO1 suppression results in inhibition of thrombospondin-1 (THBS1/TSP1), an antiangiogenic and proinflammatory cytokine that promotes insulin resistance. In EC-AGO1-KO mice, overexpression of TSP1 substantially attenuated the beneficial phenotype. In human endothelium isolated from donors with obesity or type 2 diabetes mellitus, AGO1 and THBS1 are expressed at higher levels than the healthy controls, supporting a pathological role of this pathway. CONCLUSIONS: Our study suggests a novel mechanism by which ECs, through the AGO1-TSP1 pathway, control vascularization and function of adipose tissues, insulin sensitivity, and whole-body metabolic state.


Assuntos
Tecido Adiposo Marrom/metabolismo , Proteínas Argonautas/metabolismo , Suscetibilidade a Doenças , Endotélio/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Doenças Metabólicas/etiologia , Doenças Metabólicas/metabolismo , Adulto , Animais , Proteínas Argonautas/genética , Dieta Hiperlipídica , Modelos Animais de Doenças , Metabolismo Energético , Fatores de Iniciação em Eucariotos/genética , Feminino , Perfilação da Expressão Gênica , Marcação de Genes , Loci Gênicos , Humanos , Resistência à Insulina , Masculino , Doenças Metabólicas/diagnóstico , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Modelos Biológicos , Obesidade , Fenótipo
2.
BMC Genomics ; 19(Suppl 10): 876, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30598080

RESUMO

BACKGROUND: One of the most common and recurrent vaginal infections is bacterial vaginosis (BV). The diagnosis is based on changes to the "normal" vaginal microbiome; however, the normal microbiome appears to differ according to reproductive status and ethnicity, and even among individuals within these groups. The Amsel criteria and Nugent score test are widely used for diagnosing BV; however, these tests are based on different criteria, and so may indicate distinct changes in the vaginal microbial community. Nevertheless, few studies have compared the results of these test against metagenomics analysis. METHODS: Vaginal flora samples from 77 participants were classified according to the Amsel criteria and Nugent score test. The microbiota composition was analyzed using 16S ribosome RNA gene amplicon sequencing. Bioinformatics analysis and multivariate statistical analysis were used to evaluate the microbial diversity and function. RESULTS: Only 3 % of the participants diagnosed BV negative using the Amsel criteria (A-) were BV-positive according to the Nugent score test (N+), while over half of the BV-positive patients using the Amsel criteria (A+) were BV-negative according to the Nugent score test (N-). Thirteen genera showed significant differences in distribution among BV status defined by BV tests (e.g., A - N-, A + N- and A + N+). Variations in the four most abundant taxa, Lactobacillus, Gardnerella, Prevotella, and Escherichia, were responsible for most of this dissimilarity. Furthermore, vaginal microbial diversity differed significantly among the three groups classified by the Nugent score test (N-, N+, and intermediate flora), but not between the Amsel criteria groups. Numerous predictive microbial functions, such as bacterial chemotaxis and bacterial invasion of epithelial cells, differed significantly among multiple BV test, but not between the A- and A+ groups. CONCLUSIONS: Metagenomics analysis can greatly expand our current understanding of vaginal microbial diversity in health and disease. Metagenomics profiling may also provide more reliable diagnostic criteria for BV testing.


Assuntos
Variação Genética , Microbiota/genética , Vagina/microbiologia , Adulto , DNA Bacteriano/genética , Feminino , Humanos , Vaginose Bacteriana/microbiologia
3.
BMC Genomics ; 19(Suppl 10): 904, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30598081

RESUMO

BACKGROUND: Human gut microbiome has an essential role in human health and disease. Although the major dominant microbiota within individuals have been reported, the change of gut microbiome caused by external factors, such as antibiotic use and bowel cleansing, remains unclear. We conducted this study to investigate the change of gut microbiome in overweight male adults after bowel preparation, where none of the participants had been diagnosed with any systemic diseases. METHODS: A total of 20 overweight, male Taiwanese adults were recruited, and all participants were omnivorous. The participants provided fecal samples and blood samples at three time points: prior to bowel preparation, 7 days after colonoscopy, and 28 days after colonoscopy. The microbiota composition in fecal samples was analyzed using 16S ribosome RNA gene amplicon sequencing. RESULTS: Our results demonstrated that the relative abundance of the most dominant bacteria hardly changed from prior to bowel preparation to 28 days after colonoscopy. Using the ratio of Prevotella to the sum of Prevotella and Bacteroides in the fecal samples at baseline, the participants were separated into two groups. The fecal samples of the Type 1 group was Bacteroides-dominant, and that of the Type 2 group was Prevotella-dominant with a noticeable presence Bacteroides. Bulleidia appears more in the Type 1 fecal samples, while Akkermensia appears more in the Type 2 fecal samples. Of each type, the gut microbial diversity differed slightly among the three collection times. Additionally, the Type 2 fecal microbiota was temporarily susceptible to bowel cleansing. Predictive functional analysis of microbial community reveals that their activities for the mineral absorption metabolism and arachidonic acid metabolism differed significantly between the two types. Depending on their fecal type, the variance of triglycerides and C-reactive protein also differed between the two types of participants. CONCLUSIONS: Depending upon the fecal type, the microbial diversity and the predictive functional modules of microbial community differed significantly after bowel preparation. In addition, blood biochemical markers presented somewhat associated with fecal type. Therefore, our results might provide some insights as to how knowledge of the microbial community could be used to promote health through personalized clinical treatment.


Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal , Sobrepeso/microbiologia , Adulto , Biodiversidade , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Nucleic Acids Res ; 44(D1): D209-15, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26450965

RESUMO

Circular RNAs (circRNAs) represent a new type of regulatory noncoding RNA that only recently has been identified and cataloged. Emerging evidence indicates that circRNAs exert a new layer of post-transcriptional regulation of gene expression. In this study, we utilized transcriptome sequencing datasets to systematically identify the expression of circRNAs (including known and newly identified ones by our pipeline) in 464 RNA-seq samples, and then constructed the CircNet database (http://circnet.mbc.nctu.edu.tw/) that provides the following resources: (i) novel circRNAs, (ii) integrated miRNA-target networks, (iii) expression profiles of circRNA isoforms, (iv) genomic annotations of circRNA isoforms (e.g. 282 948 exon positions), and (v) sequences of circRNA isoforms. The CircNet database is to our knowledge the first public database that provides tissue-specific circRNA expression profiles and circRNA-miRNA-gene regulatory networks. It not only extends the most up to date catalog of circRNAs but also provides a thorough expression analysis of both previously reported and novel circRNAs. Furthermore, it generates an integrated regulatory network that illustrates the regulation between circRNAs, miRNAs and genes.


Assuntos
Bases de Dados de Ácidos Nucleicos , RNA/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , RNA/química , RNA Circular , Análise de Sequência de RNA
5.
Circulation ; 131(9): 805-14, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25550450

RESUMO

BACKGROUND: Oxidative stress activates endothelial innate immunity and disrupts endothelial functions, including endothelial nitric oxide synthase-derived nitric oxide bioavailability. Here, we postulated that oxidative stress induces sterol regulatory element-binding protein 2 (SREBP2) and microRNA-92a (miR-92a), which in turn activate endothelial innate immune response, leading to dysfunctional endothelium. METHODS AND RESULTS: Using cultured endothelial cells challenged by diverse oxidative stresses, hypercholesterolemic zebrafish, and angiotensin II-infused or aged mice, we demonstrated that SREBP2 transactivation of microRNA-92a (miR-92a) is oxidative stress inducible. The SREBP2-induced miR-92a targets key molecules in endothelial homeostasis, including sirtuin 1, Krüppel-like factor 2, and Krüppel-like factor 4, leading to NOD-like receptor family pyrin domain-containing 3 inflammasome activation and endothelial nitric oxide synthase inhibition. In endothelial cell-specific SREBP2 transgenic mice, locked nucleic acid-modified antisense miR-92a attenuates inflammasome, improves vasodilation, and ameliorates angiotensin II-induced and aging-related atherogenesis. In patients with coronary artery disease, the level of circulating miR-92a is inversely correlated with endothelial cell-dependent, flow-mediated vasodilation and is positively correlated with serum level of interleukin-1ß. CONCLUSIONS: Our findings suggest that SREBP2-miR-92a-inflammasome exacerbates endothelial dysfunction during oxidative stress. Identification of this mechanism may help in the diagnosis or treatment of disorders associated with oxidative stress, innate immune activation, and endothelial dysfunction.


Assuntos
Endotélio Vascular/metabolismo , Imunidade Inata/genética , Inflamassomos/metabolismo , MicroRNAs/biossíntese , Estresse Oxidativo/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/fisiologia , Ativação Transcricional , Idoso , Angiotensina II/toxicidade , Animais , Doença das Coronárias/sangue , Doença das Coronárias/fisiopatologia , Células Endoteliais/metabolismo , Feminino , Sequestradores de Radicais Livres/farmacologia , Regulação da Expressão Gênica , Genes Reporter , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/toxicidade , Hipercolesterolemia/genética , Interleucina-1beta/sangue , Fator 4 Semelhante a Kruppel , Lipoproteínas LDL/toxicidade , Masculino , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Pessoa de Meia-Idade , Compostos Organometálicos/farmacologia , Estresse Oxidativo/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Salicilatos/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/fisiologia
6.
Nucleic Acids Res ; 42(Database issue): D78-85, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24304892

RESUMO

MicroRNAs (miRNAs) are small non-coding RNA molecules capable of negatively regulating gene expression to control many cellular mechanisms. The miRTarBase database (http://mirtarbase.mbc.nctu.edu.tw/) provides the most current and comprehensive information of experimentally validated miRNA-target interactions. The database was launched in 2010 with data sources for >100 published studies in the identification of miRNA targets, molecular networks of miRNA targets and systems biology, and the current release (2013, version 4) includes significant expansions and enhancements over the initial release (2010, version 1). This article reports the current status of and recent improvements to the database, including (i) a 14-fold increase to miRNA-target interaction entries, (ii) a miRNA-target network, (iii) expression profile of miRNA and its target gene, (iv) miRNA target-associated diseases and (v) additional utilities including an upgrade reminder and an error reporting/user feedback system.


Assuntos
Bases de Dados de Ácidos Nucleicos , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Doença/genética , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Internet , MicroRNAs/química , RNA Mensageiro/química , Análise de Sequência de RNA , Transcriptoma
7.
BMC Genomics ; 14 Suppl 1: S2, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23368412

RESUMO

BACKGROUND: MicroRNAs (miRNAs) play a critical role in down-regulating gene expression. By coupling with Argonaute family proteins, miRNAs bind to target sites on mRNAs and employ translational repression. A large amount of miRNA-target interactions (MTIs) have been identified by the crosslinking and immunoprecipitation (CLIP) and the photoactivatable-ribonucleoside-enhanced CLIP (PAR-CLIP) along with the next-generation sequencing (NGS). PAR-CLIP shows high efficiency of RNA co-immunoprecipitation, but it also lead to T to C conversion in miRNA-RNA-protein crosslinking regions. This artificial error obviously reduces the mappability of reads. However, a specific tool to analyze CLIP and PAR-CLIP data that takes T to C conversion into account is still in need. RESULTS: We herein propose the first CLIP and PAR-CLIP sequencing analysis platform specifically for miRNA target analysis, namely miRTarCLIP. From scratch, it automatically removes adaptor sequences from raw reads, filters low quality reads, reverts C to T, aligns reads to 3'UTRs, scans for read clusters, identifies high confidence miRNA target sites, and provides annotations from external databases. With multi-threading techniques and our novel C to T reversion procedure, miRTarCLIP greatly reduces the running time comparing to conventional approaches. In addition, miRTarCLIP serves with a web-based interface to provide better user experiences in browsing and searching targets of interested miRNAs. To demonstrate the superior functionality of miRTarCLIP, we applied miRTarCLIP to two public available CLIP and PAR-CLIP sequencing datasets. miRTarCLIP not only shows comparable results to that of other existing tools in a much faster speed, but also reveals interesting features among these putative target sites. Specifically, we used miRTarCLIP to disclose that T to C conversion within position 1-7 and that within position 8-14 of miRNA target sites are significantly different (p value = 0.02), and even more significant when focusing on sites targeted by top 102 highly expressed miRNAs only (p value = 0.01). These results comply with previous findings and further suggest that combining miRNA expression and PAR-CLIP data can improve accuracy of the miRNA target prediction. CONCLUSION: To sum up, we devised a systematic approach for mining miRNA-target sites from CLIP-seq and PAR-CLIP sequencing data, and integrated the workflow with a graphical web-based browser, which provides a user friendly interface and detailed annotations of MTIs. We also showed through real-life examples that miRTarCLIP is a powerful tool for understanding miRNAs. Our integrated tool can be accessed online freely at http://miRTarCLIP.mbc.nctu.edu.tw.


Assuntos
Algoritmos , MicroRNAs/metabolismo , Software , Regiões 3' não Traduzidas , Ensaios de Triagem em Larga Escala , Humanos , Imunoprecipitação , Internet , RNA/genética , RNA/metabolismo , Interface Usuário-Computador
8.
Nucleic Acids Res ; 39(Database issue): D163-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21071411

RESUMO

MicroRNAs (miRNAs), i.e. small non-coding RNA molecules (∼22 nt), can bind to one or more target sites on a gene transcript to negatively regulate protein expression, subsequently controlling many cellular mechanisms. A current and curated collection of miRNA-target interactions (MTIs) with experimental support is essential to thoroughly elucidating miRNA functions under different conditions and in different species. As a database, miRTarBase has accumulated more than 3500 MTIs by manually surveying pertinent literature after data mining of the text systematically to filter research articles related to functional studies of miRNAs. Generally, the collected MTIs are validated experimentally by reporter assays, western blot, or microarray experiments with overexpression or knockdown of miRNAs. miRTarBase curates 3576 experimentally verified MTIs between 657 miRNAs and 2297 target genes among 17 species. miRTarBase contains the largest amount of validated MTIs by comparing with other similar, previously developed databases. The MTIs collected in the miRTarBase can also provide a large amount of positive samples to develop computational methods capable of identifying miRNA-target interactions. miRTarBase is now available on http://miRTarBase.mbc.nctu.edu.tw/, and is updated frequently by continuously surveying research articles.


Assuntos
Bases de Dados de Ácidos Nucleicos , MicroRNAs/metabolismo , Regulação da Expressão Gênica , Interferência de RNA , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Integração de Sistemas , Interface Usuário-Computador
9.
Commun Biol ; 4(1): 30, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33398021

RESUMO

Diabetic kidney disease (DKD) is a major complication of diabetes. Expression of members of the microRNA (miRNA) miR-379 cluster is increased in DKD. miR-379, the most upstream 5'-miRNA in the cluster, functions in endoplasmic reticulum (ER) stress by targeting EDEM3. However, the in vivo functions of miR-379 remain unclear. We created miR-379 knockout (KO) mice using CRISPR-Cas9 nickase and dual guide RNA technique and characterized their phenotype in diabetes. We screened for miR-379 targets in renal mesangial cells from WT vs. miR-379KO mice using AGO2-immunopreciptation and CLASH (cross-linking, ligation, sequencing hybrids) and identified the redox protein thioredoxin and mitochondrial fission-1 protein. miR-379KO mice were protected from features of DKD as well as body weight loss associated with mitochondrial dysfunction, ER- and oxidative stress. These results reveal a role for miR-379 in DKD and metabolic processes via reducing adaptive mitophagy. Strategies targeting miR-379 could offer therapeutic options for DKD.


Assuntos
Albuminúria/metabolismo , Nefropatias Diabéticas/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia , Animais , Nefropatias Diabéticas/patologia , Matriz Extracelular/metabolismo , Membrana Basal Glomerular/patologia , Células Mesangiais/metabolismo , Camundongos Knockout , Mitocôndrias/metabolismo
10.
Viruses ; 13(2)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669264

RESUMO

Honeysuckle (Lonicera japonica Thunb) is a traditional Chinese medicine (TCM) with an antipathogenic activity. MicroRNAs (miRNAs) are small non-coding RNA molecules that are ubiquitously expressed in cells. Endogenous miRNA may function as an innate response to block pathogen invasion. The miRNA expression profiles of both mice and humans after the ingestion of honeysuckle were obtained. Fifteen overexpressed miRNAs overlapped and were predicted to be capable of targeting three viruses: dengue virus (DENV), enterovirus 71 (EV71) and SARS-CoV-2. Among them, let-7a was examined to be capable of targeting the EV71 RNA genome by reporter assay and Western blotting. Moreover, honeysuckle-induced let-7a suppression of EV71 RNA and protein expression as well as viral replication were investigated both in vitro and in vivo. We demonstrated that let-7a targeted EV71 at the predicted sequences using luciferase reporter plasmids as well as two infectious replicons (pMP4-y-5 and pTOPO-4643). The suppression of EV71 replication and viral load was demonstrated in two cell lines by luciferase activity, RT-PCR, real-time PCR, Western blotting and plaque assay. Furthermore, EV71-infected suckling mice fed honeysuckle extract or inoculated with let-7a showed decreased clinical scores and a prolonged survival time accompanied with decreased viral RNA, protein expression and virus titer. The ingestion of honeysuckle attenuates EV71 replication and related pathogenesis partially through the upregulation of let-7a expression both in vitro and in vivo. Our previous report and the current findings imply that both honeysuckle and upregulated let-7a can execute a suppressive function against the replication of DENV and EV71. Taken together, this evidence indicates that honeysuckle can induce the expression of let-7a and that this miRNA as well as 11 other miRNAs have great potential to prevent and suppress EV71 replication.


Assuntos
Antivirais/farmacologia , Enterovirus Humano A/efeitos dos fármacos , Lonicera/química , MicroRNAs/metabolismo , Extratos Vegetais/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Enterovirus Humano A/fisiologia , Infecções por Enterovirus/tratamento farmacológico , Humanos , Camundongos , Camundongos Endogâmicos ICR
11.
J Comput Chem ; 31(15): 2759-71, 2010 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-20839302

RESUMO

Protein acetylation, which is catalyzed by acetyltransferases, is a type of post-translational modification and crucial to numerous essential biological processes, including transcriptional regulation, apoptosis, and cytokine signaling. As the experimental identification of protein acetylation sites is time consuming and laboratory intensive, several computational approaches have been developed for identifying the candidates of experimental validation. In this work, solvent accessibility and the physicochemical properties of proteins are utilized to identify acetylated alanine, glycine, lysine, methionine, serine, and threonine. A two-stage support vector machine was applied to learn the computational models with combinations of amino acid sequences, and the accessible surface area and physicochemical properties of proteins. The predictive accuracy thus achieved is 5% to 14% higher than that of models trained using only amino acid sequences. Additionally, the substrate specificity of the acetylated site was investigated in detail with reference to the subcellular colocalization of acetyltransferases and acetylated proteins. The proposed method, N-Ace, is evaluated using independent test sets in various acetylated residues and predictive accuracies of 90% were achieved, indicating that the performance of N-Ace is comparable with that of other acetylation prediction methods. N-Ace not only provides a user-friendly input/output interface but also is a creative method for predicting protein acetylation sites. This novel analytical resource is now freely available at http://N-Ace.mbc.NCTU.edu.tw/.


Assuntos
Acetiltransferases/química , Aminoácidos/química , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , Solventes/química , Acetilação , Acetiltransferases/metabolismo , Sequência de Aminoácidos , Aminoácidos/metabolismo , Sítios de Ligação , Biocatálise , Interações Hidrofóbicas e Hidrofílicas , Ponto Isoelétrico , Proteínas/química , Termodinâmica
12.
BMC Bioinformatics ; 10: 328, 2009 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-19821977

RESUMO

BACKGROUND: MicroRNAs (miRNAs), small non-coding RNAs of 19 to 25 nt, play important roles in gene regulation in both animals and plants. In the last few years, the oligonucleotide microarray is one high-throughput and robust method for detecting miRNA expression. However, the approach is restricted to detecting the expression of known miRNAs. Second-generation sequencing is an inexpensive and high-throughput sequencing method. This new method is a promising tool with high sensitivity and specificity and can be used to measure the abundance of small-RNA sequences in a sample. Hence, the expression profiling of miRNAs can involve use of sequencing rather than an oligonucleotide array. Additionally, this method can be adopted to discover novel miRNAs. RESULTS: This work presents a systematic approach, miRExpress, for extracting miRNA expression profiles from sequencing reads obtained by second-generation sequencing technology. A stand-alone software package is implemented for generating miRNA expression profiles from high-throughput sequencing of RNA without the need for sequenced genomes. The software is also a database-supported, efficient and flexible tool for investigating miRNA regulation. Moreover, we demonstrate the utility of miRExpress in extracting miRNA expression profiles from two Illumina data sets constructed for the human and a plant species. CONCLUSION: We develop miRExpress, which is a database-supported, efficient and flexible tool for detecting miRNA expression profile. The analysis of two Illumina data sets constructed from human and plant demonstrate the effectiveness of miRExpress to obtain miRNA expression profiles and show the usability in finding novel miRNAs.


Assuntos
Biologia Computacional/métodos , MicroRNAs/química , Análise de Sequência de RNA/métodos , Software , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Genoma Humano , Genoma de Planta , Humanos
13.
Oncotarget ; 10(43): 4356-4368, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31320990

RESUMO

Background: Metastatic triple negative breast cancer (mTNBC) is a heterogeneous disease with poor prognosis. Molecular evolution of TNBC through chemotherapy selection pressure is well recognized but poorly understood. PI3K/AKT/mTOR is one of the most commonly identified oncogenic-driver pathways in breast cancer. The current study is designed to understand the genomic and transcriptomic changes, focusing on the PI3K/AKT/mTOR pathway alterations in paired primary and metastatic TNBCs. Results: Genomic analysis of 7 paired specimens identified 67 known mutations including those from the following signaling pathways: cell cycle, p53, PI3K/AKT/mTOR, RAS/MAPK, and RTK/GF. Principle coordinate analysis (PCoA) identified 4 distinctive molecular groups based on the gene expression patterns of PI3K/AKT/mTOR pathway. Key differentially-expressed genes included AKT3, GSK3B, GNA11, PI3KR1, and GNAQ. Importantly, AKT-targeted therapy showed efficacy in a patient-derived xenograft (PDX) model of TNBC in vivo. Conclusion: Genomic discordance of paired primary and metastatic TNBCs was identified, with significant increase in tumor proliferation pathways seen in metastases. Among the differentially expressed genes, AKT3 can potentially serve as a target for novel combination therapy for treatment of metastatic TNBC. Methods: Paired specimens from 10 patients with TNBCs were identified through an IRB-approved protocol (2002-2015). FoundationOneTM sequencing was performed for genomic profiling, and Affymetrix Human Genechip 2.0st was used for mRNA expression profiling. The similarity among samples was calculated based on Pearson correlation coefficients, which were used to construct hierarchical clustering and heat maps.

14.
Nat Commun ; 10(1): 1524, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944305

RESUMO

Tissues and cells in organism are continuously exposed to complex mechanical cues from the environment. Mechanical stimulations affect cell proliferation, differentiation, and migration, as well as determining tissue homeostasis and repair. By using a specially designed skin-stretching device, we discover that hair stem cells proliferate in response to stretch and hair regeneration occurs only when applying proper strain for an appropriate duration. A counterbalance between WNT and BMP-2 and the subsequent two-step mechanism are identified through molecular and genetic analyses. Macrophages are first recruited by chemokines produced by stretch and polarized to M2 phenotype. Growth factors such as HGF and IGF-1, released by M2 macrophages, then activate stem cells and facilitate hair regeneration. A hierarchical control system is revealed, from mechanical and chemical signals to cell behaviors and tissue responses, elucidating avenues of regenerative medicine and disease control by demonstrating the potential to manipulate cellular processes through simple mechanical stimulation.


Assuntos
Cabelo/fisiologia , Macrófagos/fisiologia , Regeneração/fisiologia , Animais , Proteína Morfogenética Óssea 2 , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células , Quimiocinas/genética , Quimiocinas/metabolismo , Feminino , Cabelo/crescimento & desenvolvimento , Cabelo/metabolismo , Folículo Piloso/crescimento & desenvolvimento , Folículo Piloso/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Recombinantes , Pele/citologia , Pele/metabolismo , Células-Tronco , Estresse Mecânico , Fator de Crescimento Transformador beta
15.
Sci Rep ; 9(1): 10923, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358825

RESUMO

The dysbiosis of human gut microbiota is strongly associated with the development of colorectal cancer (CRC). The dysbiotic features of the transition from advanced polyp to early-stage CRC are largely unknown. We performed a 16S rRNA gene sequencing and enterotype-based gut microbiota analysis study. In addition to Bacteroides- and Prevotella-dominated enterotypes, we identified an Escherichia-dominated enterotype. We found that the dysbiotic features of CRC were dissimilar in overall samples and especially Escherichia-dominated enterotype. Besides a higher abundance of Fusobacterium, Enterococcus, and Aeromonas in all CRC faecal microbiota, we found that the most notable characteristic of CRC faecal microbiota was a decreased abundance of potential beneficial butyrate-producing bacteria. Notably, Oscillospira was depleted in the transition from advanced adenoma to stage 0 CRC, whereas Haemophilus was depleted in the transition from stage 0 to early-stage CRC. We further identified 7 different CAGs by analysing bacterial clusters. The abundance of microbiota in cluster 3 significantly increased in the CRC group, whereas that of cluster 5 decreased. The abundance of both cluster 5 and cluster 7 decreased in the Escherichia-dominated enterotype of the CRC group. We present the first enterotype-based faecal microbiota analysis. The gut microbiota of colorectal neoplasms can be influenced by its enterotype.


Assuntos
Adenoma/microbiologia , Neoplasias Colorretais/microbiologia , Microbioma Gastrointestinal , Adenoma/patologia , Aeromonas/genética , Aeromonas/patogenicidade , Idoso , Bacteroidaceae/genética , Bacteroidaceae/patogenicidade , Neoplasias Colorretais/patologia , Enterococcus/genética , Enterococcus/patogenicidade , Escherichia/genética , Escherichia/patogenicidade , Feminino , Fusobacterium/genética , Fusobacterium/patogenicidade , Haemophilus/genética , Haemophilus/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética
16.
Noncoding RNA ; 4(4)2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30463374

RESUMO

The role and function of long non-coding RNAs (lncRNAs) in modulating gene expression is becoming apparent. Vascular endothelial growth factor A (VEGF-A) is a key regulator of blood vessel formation and maintenance making it a promising therapeutic target for activation in ischemic diseases. In this study, we uncover a functional role for two antisense VEGF-A lncRNAs, RP1-261G23.7 and EST AV731492, in transcriptional regulation of VEGF-A during hypoxia. We find here that both lncRNAs are polyadenylated, concordantly upregulated with VEGF-A, localize to the VEGF-A promoter and upstream elements in a hypoxia dependent manner either as a single-stranded RNA or DNA bound RNA, and are associated with enhancer marks H3K27ac and H3K9ac. Collectively, these data suggest that VEGF-A antisense lncRNAs, RP1-261G23.7 and EST AV731492, function as VEGF-A promoter enhancer-like elements, possibly by acting as a local scaffolding for proteins and also small RNAs to tether.

17.
Science ; 360(6393): 1126-1129, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29773668

RESUMO

Some pathogens and pests deliver small RNAs (sRNAs) into host cells to suppress host immunity. Conversely, hosts also transfer sRNAs into pathogens and pests to inhibit their virulence. Although sRNA trafficking has been observed in a wide variety of interactions, how sRNAs are transferred, especially from hosts to pathogens and pests, is still unknown. Here, we show that host Arabidopsis cells secrete exosome-like extracellular vesicles to deliver sRNAs into fungal pathogen Botrytis cinerea These sRNA-containing vesicles accumulate at the infection sites and are taken up by the fungal cells. Transferred host sRNAs induce silencing of fungal genes critical for pathogenicity. Thus, Arabidopsis has adapted exosome-mediated cross-kingdom RNA interference as part of its immune responses during the evolutionary arms race with the pathogen.


Assuntos
Arabidopsis/imunologia , Arabidopsis/microbiologia , Botrytis/patogenicidade , Interações Hospedeiro-Patógeno , Interferência de RNA , RNA de Plantas/metabolismo , RNA Interferente Pequeno/metabolismo , Botrytis/genética , Vesículas Extracelulares/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal , Virulência/genética , Fatores de Virulência/genética
18.
Nat Commun ; 9(1): 292, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29348663

RESUMO

The optimal expression of endothelial nitric oxide synthase (eNOS), the hallmark of endothelial homeostasis, is vital to vascular function. Dynamically regulated by various stimuli, eNOS expression is modulated at transcriptional, post-transcriptional, and post-translational levels. However, epigenetic modulations of eNOS, particularly through long non-coding RNAs (lncRNAs) and chromatin remodeling, remain to be explored. Here we identify an enhancer-associated lncRNA that enhances eNOS expression (LEENE). Combining RNA-sequencing and chromatin conformation capture methods, we demonstrate that LEENE is co-regulated with eNOS and that its enhancer resides in proximity to eNOS promoter in endothelial cells (ECs). Gain- and Loss-of-function of LEENE differentially regulate eNOS expression and EC function. Mechanistically, LEENE facilitates the recruitment of RNA Pol II to the eNOS promoter to enhance eNOS nascent RNA transcription. Our findings unravel a new layer in eNOS regulation and provide novel insights into cardiovascular regulation involving endothelial function.


Assuntos
Células Endoteliais/metabolismo , Elementos Facilitadores Genéticos/genética , Regulação Enzimológica da Expressão Gênica , Óxido Nítrico Sintase Tipo III/genética , RNA Longo não Codificante/genética , Animais , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/metabolismo , Regiões Promotoras Genéticas/genética , RNA Polimerase II/metabolismo , Transcrição Gênica
19.
Nucleic Acids Res ; 33(Database issue): D80-5, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15608290

RESUMO

We have developed an information repository named SpliceInfo to collect the occurrences of the four major alternative-splicing (AS) modes in human genome; these include exon skipping, 5'-alternative splicing, 3'-alternative splicing and intron retention. The dataset is derived by comparing the nucleotide and protein sequences available for a given gene for evidence of AS. Additional features such as the tissue specificity of the mRNA, the protein domain contained by exons, the GC-ratio of exons, the repeats contained within the exons, and the Gene Ontology are annotated computationally for each exonic region that is alternatively spliced. Motivated by a previous investigation of AS-related motifs such as exonic splicing enhancer and exonic splicing silencer, this resource also provides a means of identifying motifs candidates and this should help to identify potential regulatory mechanisms within a particular exonic sequence set and its two flanking intronic sequence sets. This is carried out using motif discovery tools to identify motif candidates related to alternative splicing regulation and together with a secondary structure prediction tool, will help in the identification of the structural properties of such regulatory motifs. The integrated resource is now available on http://SpliceInfo.mbc.NCTU.edu.tw/.


Assuntos
Processamento Alternativo , Bases de Dados Genéticas , Genoma Humano , Bases de Dados Genéticas/estatística & dados numéricos , Éxons , Humanos , Internet , Conformação de Ácido Nucleico , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Interface Usuário-Computador
20.
Sci Rep ; 7(1): 16540, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29184122

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity and the fourth leading malignancy and cause of cancer-related death in the male population of Taiwan. Most cases are detected at advanced stages, resulting in poor prognosis. Therefore, improved detection of early oral health disorders is indispensable. The involvement of oral bacteria in inflammation and their association with OSCC progression provide a feasible target for diagnosis. Due to the nature of oral neoplasms, the diagnosis of epithelial precursor lesions is relatively easy compared with that of other types of cancer. However, the transition from an epithelial precursor lesion to cancer is slow and requires further and continuous follow-up. In this study, we investigated microbiota differences between normal individuals, epithelial precursor lesion patients, and cancer patients with different lifestyle habits, such as betel chewing and smoking, using next-generation sequencing. Overall, the oral microbiome compositions of five genera, Bacillus, Enterococcus, Parvimonas, Peptostreptococcus, and Slackia, revealed significant differences between epithelial precursor lesion and cancer patients and correlated with their classification into two clusters. These composition changes might have the potential to constitute a biomarker to help in monitoring the oral carcinogenesis transition from epithelial precursor lesion to cancer.


Assuntos
Microbiota , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/etiologia , Saliva/microbiologia , Biodiversidade , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Biologia Computacional/métodos , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Metagenômica , Mucosa Bucal/microbiologia , Mucosa Bucal/patologia , Neoplasias Bucais/diagnóstico , RNA Ribossômico 16S , Taiwan/epidemiologia
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