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1.
Bioinformatics ; 36(20): 4977-4983, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-32756939

RESUMO

MOTIVATION: Despite of the lack of folded structure, intrinsically disordered regions (IDRs) of proteins play versatile roles in various biological processes, and many nonsynonymous single nucleotide variants (nsSNVs) in IDRs are associated with human diseases. The continuous accumulation of nsSNVs resulted from the wide application of NGS has driven the development of disease-association prediction methods for decades. However, their performance on nsSNVs in IDRs remains inferior, possibly due to the domination of nsSNVs from structured regions in training data. Therefore, it is highly demanding to build a disease-association predictor specifically for nsSNVs in IDRs with better performance. RESULTS: We present IDRMutPred, a machine learning-based tool specifically for predicting disease-associated germline nsSNVs in IDRs. Based on 17 selected optimal features that are extracted from sequence alignments, protein annotations, hydrophobicity indices and disorder scores, IDRMutPred was trained using three ensemble learning algorithms on the training dataset containing only IDR nsSNVs. The evaluation on the two testing datasets shows that all the three prediction models outperform 17 other popular general predictors significantly, achieving the ACC between 0.856 and 0.868 and MCC between 0.713 and 0.737. IDRMutPred will prioritize disease-associated IDR germline nsSNVs more reliably than general predictors. AVAILABILITY AND IMPLEMENTATION: The software is freely available at http://www.wdspdb.com/IDRMutPred. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Proteínas Intrinsicamente Desordenadas , Aprendizado de Máquina , Algoritmos , Células Germinativas , Humanos , Proteínas Intrinsicamente Desordenadas/genética , Nucleotídeos , Alinhamento de Sequência
2.
J Gene Med ; 22(7): e3177, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32096291

RESUMO

BACKGROUND: Herpes simplex virus type 1 (HSV-1)-mediated oncolytic therapy is a promising cancer treatment modality. However, viral tropism is considered to be one of the major stumbling blocks to the development of HSV-1 as an anticancer agent. METHODS: The surface of oncolytic HSV-1 G207 was covalently modified with folate-poly (ethylene glycol) conjugate (FA-PEG). The specificities and tumor targeting efficiencies of modified or unmodified G207 particles were analyzed by a real-time polymerase chain reaction at the level of cell attachment and entry. Immune responses were assessed by an interleukin-6 release assay from RAW264.7 macrophages. Biodistribution and in vivo antitumoral activity after intravenous delivery was evaluated in BALB/c nude mice bearing subcutaneous KB xenograft tumors. RESULTS: FA-PEG-HSV exhibited enhanced targeting specificity for folate receptor over-expressing tumor cells and had lower immunogenicity than the unmodified HSV. In vivo, the FA-PEG-HSV group revealed an increased anti-tumor efficiency and tumor targeting specificity compared to the naked HSV. CONCLUSIONS: These results indicate that folate-conjugated HSV G207 presents a folate receptor-targeted oncolytic virus with a potential therapeutic value via retargeting to tumor cells.


Assuntos
Ácido Fólico/análogos & derivados , Ácido Fólico/química , Herpesvirus Humano 1 , Terapia Viral Oncolítica/métodos , Polietilenoglicóis/química , Células A549 , Administração Intravenosa , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Receptores de Folato com Âncoras de GPI/química , Humanos , Imunidade , Interleucina-6/metabolismo , Células KB , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células RAW 264.7 , Distribuição Tecidual , Células Vero , Internalização do Vírus
3.
Bioinformatics ; 35(22): 4824-4826, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31161214

RESUMO

SUMMARY: The WD40-repeat proteins are a large family of scaffold molecules that assemble complexes in various cellular processes. Obtaining their structures is the key to understanding their interaction details. We present WDSPdb 2.0, a significantly updated resource providing accurately predicted secondary and tertiary structures and featured sites annotations. Based on an optimized pipeline, WDSPdb 2.0 contains about 600 thousand entries, an increase of 10-fold, and integrates more than 37 000 variants from sources of ClinVar, Cosmic, 1000 Genomes, ExAC, IntOGen, cBioPortal and IntAct. In addition, the web site is largely improved for visualization, exploring and data downloading. AVAILABILITY AND IMPLEMENTATION: http://www.wdspdb.com/wdsp/ or http://wu.scbb.pkusz.edu.cn/wdsp/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Genoma , Software , Proteínas
4.
Nucleic Acids Res ; 43(Database issue): D339-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25348404

RESUMO

WD40-repeat proteins, as one of the largest protein families, often serve as platforms to assemble functional complexes through the hotspot residues on their domain surfaces, and thus play vital roles in many biological processes. Consequently, it is highly required for researchers who study WD40 proteins and protein-protein interactions to obtain structural information of WD40 domains. Systematic identification of WD40-repeat proteins, including prediction of their secondary structures, tertiary structures and potential hotspot residues responsible for protein-protein interactions, may constitute a valuable resource upon this request. To achieve this goal, we developed a specialized database WDSPdb (http://wu.scbb.pkusz.edu.cn/wdsp/) to provide these details of WD40-repeat proteins based on our recently published method WDSP. The WDSPdb contains 63,211 WD40-repeat proteins identified from 3383 species, including most well-known model organisms. To better serve the community, we implemented a user-friendly interactive web interface to browse, search and download the secondary structures, 3D structure models and potential hotspot residues provided by WDSPdb.


Assuntos
Bases de Dados de Proteínas , Estrutura Terciária de Proteína , Ligação de Hidrogênio , Mapeamento de Interação de Proteínas , Estrutura Secundária de Proteína , Sequências Repetitivas de Aminoácidos
5.
PLoS Genet ; 10(4): e1004274, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24722121

RESUMO

Understanding of the RNA editing process has been broadened considerably by the next generation sequencing technology; however, several issues regarding this regulatory step remain unresolved--the strategies to accurately delineate the editome, the mechanism by which its profile is maintained, and its evolutionary and functional relevance. Here we report an accurate and quantitative profile of the RNA editome for rhesus macaque, a close relative of human. By combining genome and transcriptome sequencing of multiple tissues from the same animal, we identified 31,250 editing sites, of which 99.8% are A-to-G transitions. We verified 96.6% of editing sites in coding regions and 97.5% of randomly selected sites in non-coding regions, as well as the corresponding levels of editing by multiple independent means, demonstrating the feasibility of our experimental paradigm. Several lines of evidence supported the notion that the adenosine deamination is associated with the macaque editome--A-to-G editing sites were flanked by sequences with the attributes of ADAR substrates, and both the sequence context and the expression profile of ADARs are relevant factors in determining the quantitative variance of RNA editing across different sites and tissue types. In support of the functional relevance of some of these editing sites, substitution valley of decreased divergence was detected around the editing site, suggesting the evolutionary constraint in maintaining some of these editing substrates with their double-stranded structure. These findings thus complement the "continuous probing" model that postulates tinkering-based origination of a small proportion of functional editing sites. In conclusion, the macaque editome reported here highlights RNA editing as a widespread functional regulation in primate evolution, and provides an informative framework for further understanding RNA editing in human.


Assuntos
Macaca mulatta/genética , Edição de RNA/genética , RNA/genética , Adenosina/genética , Adenosina Desaminase/genética , Animais , Genoma/genética , Transcriptoma/genética
6.
J Surg Res ; 201(2): 258-65, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27020805

RESUMO

BACKGROUND: Intestinal ischemia-reperfusion (IIR) could lead to acute lung injury, associated with severe alveolar epithelial cells inflammatory and oxidative injury. Alpha7 nicotinic acetylcholine receptor (α7nAChR) is an essential component of the cholinergic anti-inflammatory pathway. The aim of this study was to investigate the important role of α7nAChR on the lung subjected to IIR. METHODS: Thirty-two Sprague-Dawley rats were randomly divided into four groups (n = 8 in each): sham group (group S), model group (group M), α7nAChR agonist PNU-282987-treated group (group PNU), and specific α7nAChR antagonist methyllycaconitine-treated group (group MLA). Intestinal IR damage was induced by clamping the superior mesenteric artery for 75 min, followed by a 120-min reperfusion. All rats were killed at 2 h after release of the clamps. The histologic examination of lungs was made, and lung water content was detected. Expression levels of malondialdehyde, tumor necrosis factor alpha, interleukin-6, and superoxide dismutase activity of the lungs were detected. Additionally, expression level of toll-like receptor (TLR)4 and nuclear factor-kappaB (NF-κB p65) in the nucleus of lung tissue and apoptosis-related protein (Bax, Bcl-2, and cleaved-caspase3) were detected using Western blot. RESULTS: Lungs were damaged after intestine IR, manifested by higher lung water content, histologic score, concentrations of interleukin-6, tumor necrosis factor alpha, and malondialdehyde of group M than those of group S, accompanied with decreased superoxide dismutase activity (P < 0.05). PNU treatment could significantly improve the pulmonary function of rats subjected to IIR. These effects of activation of α7nAChR were associated with suppression of TLR4/NF-κB pathway and subsequent reduction of apoptosis-related protein. However, MLA treatment aggravated lung injury. CONCLUSIONS: α7nAChR plays a role in acute lung injury induced by IIR via attenuating lung oxidative stress and inflammation through suppression of TLR4/NF-κB pathway, resulting in reduction of apoptosis in the lung.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Benzamidas/uso terapêutico , Compostos Bicíclicos com Pontes/uso terapêutico , Intestinos/irrigação sanguínea , Traumatismo por Reperfusão/complicações , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/metabolismo , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Avaliação Pré-Clínica de Medicamentos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , NF-kappa B/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
7.
BMC Genomics ; 14: 523, 2013 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-23902230

RESUMO

BACKGROUND: S. erythraea is a Gram-positive filamentous bacterium used for the industrial-scale production of erythromycin A which is of high clinical importance. In this work, we sequenced the whole genome of a high-producing strain (E3) obtained by random mutagenesis and screening from the wild-type strain NRRL23338, and examined time-series expression profiles of both E3 and NRRL23338. Based on the genomic data and transcriptpmic data of these two strains, we carried out comparative analysis of high-producing strain and wild-type strain at both the genomic level and the transcriptomic level. RESULTS: We observed a large number of genetic variants including 60 insertions, 46 deletions and 584 single nucleotide variations (SNV) in E3 in comparison with NRRL23338, and the analysis of time series transcriptomic data indicated that the genes involved in erythromycin biosynthesis and feeder pathways were significantly up-regulated during the 60 hours time-course. According to our data, BldD, a previously identified ery cluster regulator, did not show any positive correlations with the expression of ery cluster, suggesting the existence of alternative regulation mechanisms of erythromycin synthesis in S. erythraea. Several potential regulators were then proposed by integration analysis of genomic and transcriptomic data. CONCLUSION: This is a demonstration of the functional comparative genomics between an industrial S. erythraea strain and the wild-type strain. These findings help to understand the global regulation mechanisms of erythromycin biosynthesis in S. erythraea, providing useful clues for genetic and metabolic engineering in the future.


Assuntos
Eritromicina/biossíntese , Genoma Bacteriano , Saccharopolyspora/genética , Transcriptoma , Hibridização Genômica Comparativa , Genômica/métodos , Anotação de Sequência Molecular , Saccharopolyspora/classificação , Saccharopolyspora/metabolismo
8.
World J Surg Oncol ; 11: 56, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23496874

RESUMO

BACKGROUND: To confirm whether clinical and biochemical parameters or Hashimoto's thyroiditis (HT) could predict the risks of malignancy among subjects who underwent thyroidectomy, as well as to determine the influence of HT on the biological behavior of papillary thyroid cancer (PTC). METHODS: A total of 2,052 patients who underwent initial thyroidectomy were enrolled between June 2006 and August 2008. Serum free T4, free T3, thyrotropin (TSH), thyroglobulin, thyroglobulin antibody, antimicrosomal antibody, tumor-associated status, and thyroid disorders were documented. RESULTS: Binary logistic regression analysis was performed to define the risk predictors for thyroid cancer. Finally, calcification, HT, TSH, and age, were entered into the multivariate model. Multivariate logistic regression analysis revealed the risk of thyroid cancer increases in parallel with TSH concentration within normal range, and the risk for malignancy significantly increased with serum TSH 1.97-4.94 mIU/L, compared with TSH less than 0.35 mIU/L (OR = 1.951, 95% CI = 1.201-3.171, P = 0.007). Increased risks of thyroid cancer were also detected among the patients with HT (OR = 3.732, 95% CI = 2.563-5.435), and microcalcification (OR = 14.486, 95% CI = 11.374-18.449). The effects of HT on the aggressiveness of PTC were not observed in extrathyroidal invasion (P = 0.347), capsular infiltration (P = 0.345), angioinvasion (P = 0.512), and lymph node metastases (P = 0.634). CONCLUSIONS: The risk of malignancy increases in patients with higher level TSH within normal range, as well as the presence of HT and microcalcification. No evidence suggests that coexistent HT alleviates the aggressiveness of PTC.


Assuntos
Calcinose/complicações , Carcinoma Papilar/etiologia , Doença de Hashimoto/complicações , Neoplasias da Glândula Tireoide/etiologia , Tireotropina/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcinose/sangue , Calcinose/patologia , Carcinoma Papilar/sangue , Carcinoma Papilar/patologia , Criança , Pré-Escolar , Feminino , Seguimentos , Doença de Hashimoto/sangue , Doença de Hashimoto/patologia , Humanos , Lactente , Recém-Nascido , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
9.
J Orthop Translat ; 40: 132-146, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37457309

RESUMO

Background: Eurycomanone (EN) is a diterpenoid compound isolated from the roots of Eurycoma longifolia (E. longifolia). Previous studies have confirmed that E. longifolia can enhance bone regeneration and bone strength. We previously isolated and identified ten quassinoids from E. longifolia, and the result displayed that five aqueous extracts have the effects on promotion of bone formation, among whom EN showed the strongest activity. However, the molecular mechanism of EN on bone formation was unknown, and we further investigated in this study. Methods: After the verification of purity of extracted EN, following experiments were conducted. Firstly, the pharmacologic action of EN on normal bone mineralization and the therapeutic effect of EN on Dex-induced bone loss using zebrafish larvae. The mineralization area and integral optical density (IOD) were evaluated using alizarin red staining. Then the vital signaling pathways of EN relevant to OP was identified through network pharmacology analysis. Eventually in vitro, the effect of EN on cell viability, osteogenesis activities were investigated in human bone marrow mesenchymal stem cells (hMSCs) and C3H10 cells, and the molecular mechanisms by which applying AKT inhibitor A-443654 in hMSCs. Results: In zebrafish larvae, the administration in medium of EN (0.2, 1, and 5 µM) dramatically enhanced the skull mineralization area and integral optical density (IOD), and increased mRNA expressions of osteoblast formation genes (ALP, RUNX2a, SP7, OCN). Meanwhile, exposure of EN remarkably alleviated the inhibition of bone formation induced by dexamethasone (Dex), prominently improved the mineralization, up-regulated osteoblast-specific genes and down-regulated osteoclast-related genes (CTSK, RANKL, NFATc1, TRAF6) in Dex-treated bone loss zebrafish larvae. Network pharmacology outcomes showed the MAPK and PI3K-AKT signaling pathways are closely associated with 10 hub genes (especially AKT1), and AKT/GSK-3ß/ß-catenin was selected as the candidate analysis pathway. In hMSCs and C3H10 cells, results showed that EN at appropriate concentrations of 0.008-5 µM effectively increased the cell proliferation. In addition, EN (0.04, 0.2, and 1 µM) significantly stimulated osteogenic differentiation and mineralization as well as significantly increased the protein phosphorylation of AKT and GSK-3ß, and expression of ß-catenin, evidencing by the results of ALP and ARS staining, qPCR and western blotting. Whereas opposite results were presented in hMSCs when treated with AKT inhibitor A-443654, which effectively inhibited the pro-osteogenesis effect induced by EN, suggesting EN represent powerful potential in promoting osteogenesis of hMSCs, which may be closely related to the AKT/GSK-3ß/ß-catenin signaling pathway. Conclusions: Altogether, our findings indicate that EN possesses remarkable effect on bone formation via activating AKT/GSK-3ß/ß-catenin signaling pathway in most tested concentrations. The translational potential of this article: This study demonstrates EN is a new effective monomer in promoting bone formation, which may be a promising anabolic agent for osteoporosis (OP) treatment.

10.
Biochem Biophys Res Commun ; 419(1): 99-103, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22326261

RESUMO

Many non-synonymous SNPs (nsSNPs) are associated with diseases, and numerous machine learning methods have been applied to train classifiers for sorting disease-associated nsSNPs from neutral ones. The continuously accumulated nsSNP data allows us to further explore better prediction approaches. In this work, we partitioned the training data into 20 subsets according to either original or substituted amino acid type at the nsSNP site. Using support vector machine (SVM), training classification models on each subset resulted in an overall accuracy of 76.3% or 74.9% depending on the two different partition criteria, while training on the whole dataset obtained an accuracy of only 72.6%. Moreover, the dataset was also randomly divided into 20 subsets, but the corresponding accuracy was only 73.2%. Our results demonstrated that partitioning the whole training dataset into subsets properly, i.e., according to the residue type at the nsSNP site, will improve the performance of the trained classifiers significantly, which should be valuable in developing better tools for predicting the disease-association of nsSNPs.


Assuntos
Inteligência Artificial , Doença/genética , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Bases de Dados de Ácidos Nucleicos , Predisposição Genética para Doença , Humanos
11.
Technol Cancer Res Treat ; 21: 15330338221138208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36583563

RESUMO

Background: Epidemiologic studies have produced conflicting results on the effects of metformin on pancreatic cancer. This study aimed to observe and analyze whether metformin use is associated with better prognosis in pancreatic cancer. Materials and Methods: In this retrospective cohort study, all baseline data were retrieved from The Chinese Medicine Information Retrieval System (https://dc.wzhospital.cn/vpn/index.html) of The First Affiliated Hospital of Wenzhou Medical University. Survival data were collected by follow-up visits and medical records. Overall survival was the primary endpoint, while progression-free survival and disease-free survival were secondary endpoints. Progression or recurrence was assessed with radiologic images. Results: Seventy-six metformin users and 92 metformin nonusers diagnosed with pancreatic cancer from 2012 to 2020 in this hospital were enrolled. The adjusted hazard ratio for overall survival for metformin users was 0.50 (95% confidence interval = 0.33-0.76), where median overall survival was 16.0 months for metformin users versus 11.5 months for metformin nonusers. The protective effect was also found by analyzing progression-free survival (adjusted hazard ratio = 0.39, 95% confidence interval = 0.18-0.86) and disease-free survival (adjusted hazard ratio = 0.30, 95% confidence interval = 0.14-0.68). In the subgroup analysis, metformin use had a statistically significant association with prolongation of survival in stage I to II pancreatic cancer patients (hazard ratio = 0.47, 95% confidence interval = 0.25-0.91), but not for advanced tumor stage (hazard ratio for IV stage = 0.62, 95% confidence interval = 0.33-1.19), after adjustment for other risk factors. Conclusion: Metformin use is related to favorable survival outcomes of pancreatic cancer, especially in early tumor stage.


Assuntos
Metformina , Neoplasias Pancreáticas , Humanos , Metformina/uso terapêutico , Metformina/farmacologia , Estudos Retrospectivos , Neoplasias Pancreáticas/patologia , Intervalo Livre de Doença , Neoplasias Pancreáticas
12.
BMC Bioinformatics ; 12: 315, 2011 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-21806838

RESUMO

BACKGROUND: Differential coexpression analysis (DCEA) is increasingly used for investigating the global transcriptional mechanisms underlying phenotypic changes. Current DCEA methods mostly adopt a gene connectivity-based strategy to estimate differential coexpression, which is characterized by comparing the numbers of gene neighbors in different coexpression networks. Although it simplifies the calculation, this strategy mixes up the identities of different coexpression neighbors of a gene, and fails to differentiate significant differential coexpression changes from those trivial ones. Especially, the correlation-reversal is easily missed although it probably indicates remarkable biological significance. RESULTS: We developed two link-based quantitative methods, DCp and DCe, to identify differentially coexpressed genes and gene pairs (links). Bearing the uniqueness of exploiting the quantitative coexpression change of each gene pair in the coexpression networks, both methods proved to be superior to currently popular methods in simulation studies. Re-mining of a publicly available type 2 diabetes (T2D) expression dataset from the perspective of differential coexpression analysis led to additional discoveries than those from differential expression analysis. CONCLUSIONS: This work pointed out the critical weakness of current popular DCEA methods, and proposed two link-based DCEA algorithms that will make contribution to the development of DCEA and help extend it to a broader spectrum.


Assuntos
Diabetes Mellitus Tipo 2/genética , Perfilação da Expressão Gênica/métodos , Algoritmos , Etiquetas de Sequências Expressas , Regulação da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos
13.
BMC Evol Biol ; 11: 1, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21194491

RESUMO

BACKGROUND: Lactic acid bacteria (LAB) are important in the food industry for the production of fermented food products and in human health as commensals in the gut. However, the phylogenetic relationships among LAB species remain under intensive debate owing to disagreements among different data sets. RESULTS: We performed a phylogenetic analysis of LAB species based on 232 genes from 28 LAB genome sequences. Regardless of the tree-building methods used, combined analyses yielded an identical, well-resolved tree topology with strong supports for all nodes. The LAB species examined were divided into two groups. Group 1 included families Enterococcaceae and Streptococcaceae. Group 2 included families Lactobacillaceae and Leuconostocaceae. Within Group 2, the LAB species were divided into two clades. One clade comprised of the acidophilus complex of genus Lactobacillus and two other species, Lb. sakei and Lb. casei. In the acidophilus complex, Lb. delbrueckii separated first, while Lb. acidophilus/Lb. helveticus and Lb. gasseri/Lb. johnsonii were clustered into a sister group. The other clade within Group 2 consisted of the salivarius subgroup, including five species, Lb. salivarius, Lb. plantarum, Lb. brevis, Lb. reuteri, Lb. fermentum, and the genera Pediococcus, Oenococcus, and Leuconostoc. In this clade, Lb. salivarius was positioned most basally, followed by two clusters, one corresponding to Lb. plantarum/Lb. brevis pair and Pediococcus, and the other including Oenococcus/Leuconostoc pair and Lb. reuteri/Lb. fermentum pair. In addition, phylogenetic utility of the 232 genes was analyzed to identify those that may be more useful than others. The genes identified as useful were related to translation and ribosomal structure and biogenesis (TRSB), and a three-gene set comprising genes encoding ultra-violet resistance protein B (uvrB), DNA polymerase III (polC) and penicillin binding protein 2B (pbpB). CONCLUSIONS: Our phylogenomic analyses provide important insights into the evolution and diversification of LAB species, and also revealed the phylogenetic utility of several genes. We infer that the occurrence of multiple, independent adaptation events in LAB species, have resulted in their occupation of various habitats. Further analyses of more genes from additional, representative LAB species are needed to reveal the molecular mechanisms underlying adaptation of LAB species to various environmental niches.


Assuntos
Genômica , Lactobacillales/classificação , Filogenia , Genoma Bacteriano , Ácido Láctico/metabolismo , Lactobacillales/genética , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Dados de Sequência Molecular
14.
Front Genet ; 12: 650897, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34108988

RESUMO

Diamond-Blackfan Anemia (DBA) is an inherited rare disease characterized with severe pure red cell aplasia, and it is caused by the defective ribosome biogenesis stemming from the impairment of ribosomal proteins. Among all DBA-associated ribosomal proteins, RPS19 affects most patients and carries most DBA mutations. Revealing how these mutations lead to the impairment of RPS19 is highly demanded for understanding the pathogenesis of DBA, but a systematic study is currently lacking. In this work, based on the complex structure of human ribosome, we comprehensively studied the structural basis of DBA mutations of RPS19 by using computational methods. Main structure elements and five conserved surface patches involved in RPS19-18S rRNA interaction were identified. We further revealed that DBA mutations would destabilize RPS19 through disrupting the hydrophobic core or breaking the helix, or perturb the RPS19-18S rRNA interaction through destroying hydrogen bonds, introducing steric hindrance effect, or altering surface electrostatic property at the interface. Moreover, we trained a machine-learning model to predict the pathogenicity of all possible RPS19 mutations. Our work has laid a foundation for revealing the pathogenesis of DBA from the structural perspective.

15.
Front Bioeng Biotechnol ; 9: 772397, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900963

RESUMO

Motility is finely regulated and is crucial to bacterial processes including colonization and biofilm formation. There is a trade-off between motility and growth in bacteria with molecular mechanisms not fully understood. Hypermotile Escherichia coli could be isolated by evolving non-motile cells on soft agar plates. Most of the isolates carried mutations located upstream of the flhDC promoter region, which upregulate the transcriptional expression of the master regulator of the flagellum biosynthesis, FlhDC. Here, we identified that spontaneous mutations in clpX boosted the motility of E. coli largely, inducing several folds of changes in swimming speed. Among the mutations identified, we further elucidated the molecular mechanism underlying the ClpXV78F mutation on the regulation of E. coli motility. We found that the V78F mutation affected ATP binding to ClpX, resulting in the inability of the mutated ClpXP protease to degrade FlhD as indicated by both structure modeling and in vitro protein degradation assays. Moreover, our proteomic data indicated that the ClpXV78F mutation elevated the stability of known ClpXP targets to various degrees with FlhD as one of the most affected. In addition, the specific tag at the C-terminus of FlhD being recognized for ClpXP degradation was identified. Finally, our transcriptome data characterized that the enhanced expression of the motility genes in the ClpXV78F mutations was intrinsically accompanied by the reduced expression of stress resistance genes relating to the reduced fitness of the hypermotile strains. A similar pattern was observed for previously isolated hypermotile E. coli strains showing high expression of flhDC at the transcriptional level. Hence, clpX appears to be a hot locus comparable to the upstream of the flhDC promoter region evolved to boost bacterial motility, and our finding provides insight into the reduced fitness of the hypermotile bacteria.

16.
Front Oncol ; 11: 737867, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604079

RESUMO

BACKGROUND: Genomic instability (GI) is among the top ten characteristics of malignancy. Long non-coding RNAs (lncRNAs) are promising cancer biomarkers that are reportedly involved in GI. So far, the clinical value of GI-related lncRNAs (GIlncs) in papillary thyroid cancer (PTC) has not been clarified. METHODS: Integrative analysis of lncRNA expression and somatic mutation profiles was performed to identify GIlncs. Analysis of differentially expressed lncRNAs in the group with high- and low- cumulative number of somatic mutations revealed significant GIlncs in PTC. Univariate and multivariate Cox proportional hazard regression analyses were performed to identify hub-GIlncs. RESULTS: A computational model based on four lncRNAs (FOXD2-AS1, LINC01614, AC073257.2, and AC005082.1) was identified as a quantitative index using an in-silicon discovery cohort. GILS score was significantly associated with poor prognosis, as validated in the TCGA dataset and further tested in our local RNA-Seq cohort. Moreover, a combination of clinical characteristics and the composite GILS-clinical prognostic nomogram demonstrates satisfactory discrimination and calibration. Furthermore, the GILS score and FOXD2-AS1, LINC01614, AC073257.2, and AC005082.1 were also associated with driver mutations and multiple clinical-pathological variables, respectively. Moreover, RNA-Seq confirmed the expression patterns of FOXD2-AS1, LINC01614, AC073257.2, and AC005082.1 in PTC and normal thyroid tissues. Biological experiments demonstrated that downregulated or overexpressed LINC01614 affect PTC cell proliferation, migration, and invasion in vitro. Activation of the stromal and immune cell infiltration was also observed in the high LINC01614 group in the PTC microenvironment. CONCLUSION: In summary, we identified a signature for clinical outcome prediction in PTC comprising four lncRNAs associated with GI. A better understanding of the GI providing an alternative evaluation of the progression risk of PTC. Our study also demonstrated LINC01614 as a novel oncogenic lncRNA and verified its phenotype in PTC.

17.
Front Biosci (Landmark Ed) ; 26(12): 1422-1433, 2021 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-34994157

RESUMO

BACKGROUND: The wide application of gene sequencing has accumulated numerous amino acid substitutions (AAS) with unknown significance, posing significant challenges to predicting and understanding their pathogenicity. While various prediction methods have been proposed, most are sequence-based and lack insights for molecular mechanisms from the perspective of protein structures. Moreover, prediction performance must be improved. METHODS: Herein, we trained a random forest (RF) prediction model, namely AAS3D-RF, underscoring sequence and three-dimensional (3D) structure-based features to explore the relationship between diseases and AASs. RESULTS: AAS3D-RF was trained on more than 14,000 AASs with 21 selected features, and obtained accuracy (ACC) between 0.811 and 0.839 and Matthews correlation coefficient (MCC) between 0.591 and 0.684 on two independent testing datasets, superior to seven existing tools. In addition, AAS3D-RF possesses unique structure-based features, context-dependent substitution score (CDSS) and environment-dependent residue contact energy (ERCE), which could be applied to interpret whether pathogenic AASs would introduce incompatibilities to the protein structural microenvironments. CONCLUSION: AAS3D-RF serves as a valuable tool for both predicting and understanding pathogenic AASs.


Assuntos
Proteínas , Substituição de Aminoácidos , Proteínas/genética
18.
Oncol Lett ; 21(2): 139, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33552258

RESUMO

Senescence is activated in response to gemcitabine to prevent the propagation of cancer cells. However, there is little evidence on whether senescence is involved in gemcitabine resistance in pancreatic cancer. Increasing evidence has demonstrated that microRNAs (miRs) are potential regulators of cellular senescence. The present study aimed to investigate whether aberrant miR-7 expression modulated senescence to influence pancreatic cancer resistance to chemotherapy. In the present study, cell senescence assay, ALDEFLUOR™ assay, luciferase reporter assay, flow cytometry, quantitative PCR, immunohistochemistry and western blot analysis were performed to explore the association between senescence and gemcitabine therapy response, and to clarify the underlying mechanisms. The present study revealed that gemcitabine-induced chronically existing senescent pancreatic cells possessed stemness markers. Therapy-induced senescence led to gemcitabine resistance. Additionally, it was found that miR-7 expression was decreased in gemcitabine-resistant pancreatic cancer cells, and that miR-7 acted as an important regulator of cellular senescence by targeting poly (ADP-ribose) polymerase 1 (PARP1)/NF-κB signaling. When miR-7 expression was restored, it was able to sensitize pancreatic cancer cells to gemcitabine. In conclusion, the present study demonstrated that miR-7 regulated cellular senescence and relieved gemcitabine resistance by targeting the PARP1/NF-κB axis in pancreatic cancer cells.

19.
Cancer Manag Res ; 12: 12557-12567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324100

RESUMO

BACKGROUND: Microfibril-associated protein 2 (MFAP2) is a protein coding gene that exerts important phenotypic effects on cell motility, and increasing research has indicated that MFAP2 was correlated with many cancers. However, the functional and potential clinical role of MFAP2 in papillary thyroid cancer (PTC) has not yet been verified. MATERIALS AND METHODS: We performed whole transcriptome sequencing on 78 paired PTC tissues and corresponding adjacent normal tissues and found that MFAP2 was highly expressed in PTC tissues. Then, we analyzed the expression of MFAP2 and its relation with the clinicopathological features of PTC in The Cancer Genome Atlas (TCGA) PTC genomic dataset. We detected MFAP2 expression in 40 paired PTC tissues and corresponding adjacent normal tissues through RT-qPCR (real time-quantitative polymerase chain reaction) to validate the sequencing data and TCGA cohort. Cell functional assays were performed to elucidate the function of MFAP2 in PTC cells, Western blot assay was performed to explore the correlation between MFAP2 and EMT (epithelial-mesenchymal transition)-related proteins. RESULTS: Statistical analysis showed that MFAP2 was obviously upregulated in PTC tissues compared to matched normal tissues, and the expression levels of MFAP2 in PTC tissues were strongly related with lymph node metastasis (p=0.016). The results of RT-qPCR of our own tissue specimens showed the same conclusions as that in TCGA dataset. The results of functional assays in PTC cell lines showed that MFAP2 could promote proliferation, colony formation, migration and invasion abilities and decrease the apoptotic rate in PTC cells. Western Blot assay showed that MFAP2 could regulate the expression of EMT-related proteins. CONCLUSION: MFAP2 increases the proliferation, motility and decreases the apoptosis of PTC cells, and might be a potential therapeutic target for papillary thyroid cancer.

20.
Dis Markers ; 2020: 2782101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32566037

RESUMO

MicroRNAs play critical roles in tumor progression. Our recent study has indicated that microRNA-7 (miR-7) impairs autophagy-derived pools of glucose to suppress the glycolysis in pancreatic cancer progression. However, the roles of miR-7 in clinical significance and chemoresistance of pancreatic cancer remain unexplored. The aim of this study was to assess the expression of miR-7 in patients with pancreatic cancer and to evaluate the possibility of its usage as a prognostic molecular biomarker. MicroRNA array-based quantification analysis of 372 miRNAs was compared in serum between pancreatic cancer and healthy individuals, gemcitabine-sensitive and gemcitabine-resistance patients. We identified miR-7 showed the potential predictive power for gemcitabine-sensitive patients with pancreatic cancer. Then, the results were validated in pancreatic tissue microarray and The Cancer Genome Atlas (TCGA) dataset, demonstrating that lower miR-7 expression was correlated with more advanced tumor stages and worse prognosis in pancreatic cancer. The Cox proportional-hazards model analysis identified miR-7 to be an independent variable for prediction of the survival. Furthermore, the mechanistic exploration suggested the clinical significance of miR-7 involved its interference effect on autophagy and glycolysis in pancreatic cancer using pancreatic cancer tissue microarrays and TCGA data. Therefore, the results of the present study provide evidences that low microRNA-7 expression may contribute to tumor progression and poor prognosis in pancreatic cancer.


Assuntos
Biomarcadores Tumorais/sangue , MicroRNA Circulante/sangue , MicroRNAs/sangue , Neoplasias Pancreáticas/sangue , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Gencitabina
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