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1.
Nucleic Acids Res ; 49(D1): D1012-D1019, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33104797

RESUMO

RNA editing is a relevant epitranscriptome phenomenon able to increase the transcriptome and proteome diversity of eukaryotic organisms. ADAR mediated RNA editing is widespread in humans in which millions of A-to-I changes modify thousands of primary transcripts. RNA editing has pivotal roles in the regulation of gene expression or modulation of the innate immune response or functioning of several neurotransmitter receptors. Massive transcriptome sequencing has fostered the research in this field. Nonetheless, different aspects of the RNA editing biology are still unknown and need to be elucidated. To support the study of A-to-I RNA editing we have updated our REDIportal catalogue raising its content to about 16 millions of events detected in 9642 human RNAseq samples from the GTEx project by using a dedicated pipeline based on the HPC version of the REDItools software. REDIportal now allows searches at sample level, provides overviews of RNA editing profiles per each RNAseq experiment, implements a Gene View module to look at individual events in their genic context and hosts the CLAIRE database. Starting from this novel version, REDIportal will start collecting non-human RNA editing changes for comparative genomics investigations. The database is freely available at http://srv00.recas.ba.infn.it/atlas/index.html.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Regulação da Expressão Gênica , Proteoma/genética , Edição de RNA/genética , Transcriptoma/genética , Sequência de Bases/genética , Curadoria de Dados/métodos , Mineração de Dados/métodos , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Humanos , Internet , Proteômica/métodos
2.
Int J Mol Sci ; 24(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37511429

RESUMO

Molecular dynamics simulation is a widely employed computational technique for studying the dynamic behavior of molecular systems over time. By simulating macromolecular biological systems consisting of a drug, a receptor and a solvated environment with thousands of water molecules, MD allows for realistic ligand-receptor binding interactions (lrbi) to be studied. In this study, we present MD-ligand-receptor (MDLR), a state-of-the-art software designed to explore the intricate interactions between ligands and receptors over time using molecular dynamics trajectories. Unlike traditional static analysis tools, MDLR goes beyond simply taking a snapshot of ligand-receptor binding interactions (lrbi), uncovering long-lasting molecular interactions and predicting the time-dependent inhibitory activity of specific drugs. With MDLR, researchers can gain insights into the dynamic behavior of complex ligand-receptor systems. Our pipeline is optimized for high-performance computing, capable of efficiently processing vast molecular dynamics trajectories on multicore Linux servers or even multinode HPC clusters. In the latter case, MDLR allows the user to analyze large trajectories in a very short time. To facilitate the exploration and visualization of lrbi, we provide an intuitive Python notebook (Jupyter), which allows users to examine and interpret the results through various graphical representations.


Assuntos
Simulação de Dinâmica Molecular , Software , Ligantes , Ligação Proteica
3.
Int J Mol Sci ; 25(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38203410

RESUMO

Chronic exposure to ultraviolet (UV) radiation is known to induce the formation of DNA photo-adducts, including cyclobutane pyrimidine dimers (CPDs) and Dewar valence derivatives (DVs). While CPDs usually occur at higher frequency than DVs, recent studies have shown that the latter display superior selectivity and significant stability in interaction with the human DNA/topoisomerase 1 complex (TOP1). With the aim to deeply investigate the mechanism of interaction of DVs with TOP1, we report here four all-atom molecular dynamic simulations spanning one microsecond. These simulations are focused on the stability and conformational changes of two DNA/TOP1-DV complexes in solution, the data being compared with the biomimetic thymine dimer counterparts. Results from root-mean-square deviation (RMSD) and root-mean-square fluctuation (RMSF) analyses unequivocally confirmed increased stability of the DNA/TOP1-DV complexes throughout the simulation duration. Detailed interaction analyses, uncovering the presence of salt bridges, hydrogen bonds, water-mediated interactions, and hydrophobic interactions, as well as pinpointing the non-covalent interactions within the complexes, enabled the identification of specific TOP1 residues involved in the interactions over time and suggested a potential TOP1 inhibition mechanism in action.


Assuntos
DNA Topoisomerases Tipo I , Simulação de Dinâmica Molecular , Humanos , Biomimética , Adutos de DNA , Interpretação Estatística de Dados , Dímeros de Pirimidina
4.
Int J Mol Sci ; 23(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35055101

RESUMO

We report here the synthesis of novel thymine biomimetic photo-adducts bearing an alkane spacer between nucleobases and characterized by antimelanoma activity against two mutated cancer cell lines overexpressing human Topoisomerase 1 (TOP1), namely SKMEL28 and RPMI7951. Among them, Dewar Valence photo-adducts showed a selectivity index higher than the corresponding pyrimidine-(6-4)-pyrimidone and cyclobutane counterpart and were characterized by the highest affinity towards TOP1/DNA complex as evaluated by molecular docking analysis. The antimelanoma activity of novel photo-adducts was retained after loading into UV photo-protective lignin nanoparticles as stabilizing agent and efficient drug delivery system. Overall, these results support a combined antimelanoma and UV sunscreen strategy involving the use of photo-protective lignin nanoparticles for the controlled release of thymine dimers on the skin followed by their sacrificial transformation into photo-adducts and successive inhibition of melanoma and alert of cellular UV machinery repair pathways.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Mimetismo Biológico , Portadores de Fármacos/química , Lignina , Nanopartículas , Timina/química , Biomimética , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos , Lignina/química , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Nanopartículas/química , Nanopartículas/ultraestrutura , Fotoquímica , Dímeros de Pirimidina/química , Solventes , Análise Espectral , Relação Estrutura-Atividade , Raios Ultravioleta
5.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36498979

RESUMO

Human Topoisomerase I (hTop1p) is a ubiquitous enzyme that relaxes supercoiled DNA through a conserved mechanism involving transient breakage, rotation, and binding. Htop1p is the molecular target of the chemotherapeutic drug camptothecin (CPT). It causes the hTop1p-DNA complex to slow down the binding process and clash with the replicative machinery during the S phase of the cell cycle, forcing cells to activate the apoptotic response. This gives hTop1p a central role in cancer therapy. Recently, two artesunic acid derivatives (compounds c6 and c7) have been proposed as promising inhibitors of hTop1p with possible antitumor activity. We used several computational approaches to obtain in silico confirmations of the experimental data and to form a comprehensive dynamic description of the ligand-receptor system. We performed molecular docking analyses to verify the ability of the two new derivatives to access the enzyme-DNA interface, and a classical molecular dynamics simulation was performed to assess the capacity of the two compounds to maintain a stable binding pose over time. Finally, we calculated the noncovalent interactions between the two new derivatives and the hTop1p receptor in order to propose a possible inhibitory mechanism like that adopted by CPT.


Assuntos
DNA Topoisomerases Tipo I , Inibidores da Topoisomerase I , Humanos , DNA Topoisomerases Tipo I/metabolismo , Simulação de Acoplamento Molecular , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/química , Inibidores Enzimáticos/farmacologia , Camptotecina , DNA/química , Simulação de Dinâmica Molecular
6.
Nucleic Acids Res ; 47(1): 221-236, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30462294

RESUMO

8-Oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) is one of the major DNA modifications and a potent pre-mutagenic lesion prone to mispair with 2'-deoxyadenosine (dA). Several thousand residues of 8-oxodG are constitutively generated in the genome of mammalian cells, but their genomic distribution has not yet been fully characterized. Here, by using OxiDIP-Seq, a highly sensitive methodology that uses immuno-precipitation with efficient anti-8-oxodG antibodies combined with high-throughput sequencing, we report the genome-wide distribution of 8-oxodG in human non-tumorigenic epithelial breast cells (MCF10A), and mouse embryonic fibroblasts (MEFs). OxiDIP-Seq revealed sites of 8-oxodG accumulation overlapping with γH2AX ChIP-Seq signals within the gene body of transcribed long genes, particularly at the DNA replication origins contained therein. We propose that the presence of persistent single-stranded DNA, as a consequence of transcription-replication clashes at these sites, determines local vulnerability to DNA oxidation and/or its slow repair. This oxidatively-generated damage, likely in combination with other kinds of lesion, might contribute to the formation of DNA double strand breaks and activation of DNA damage response.


Assuntos
Dano ao DNA/genética , Replicação do DNA/genética , Desoxiguanosina/análogos & derivados , Histonas/genética , 8-Hidroxi-2'-Desoxiguanosina , Animais , Linhagem Celular Tumoral , Mapeamento Cromossômico , DNA/química , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Desoxiadenosinas/genética , Desoxiguanosina/genética , Fibroblastos/metabolismo , Genoma/genética , Humanos , Camundongos , Oxirredução , Origem de Replicação/genética
7.
BMC Bioinformatics ; 21(Suppl 10): 353, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32838738

RESUMO

BACKGROUND: RNA editing is a widespread co-/post-transcriptional mechanism that alters primary RNA sequences through the modification of specific nucleotides and it can increase both the transcriptome and proteome diversity. The automatic detection of RNA-editing from RNA-seq data is computational intensive and limited to small data sets, thus preventing a reliable genome-wide characterisation of such process. RESULTS: In this work we introduce HPC-REDItools, an upgraded tool for accurate RNA-editing events discovery from large dataset repositories. AVAILABILITY: https://github.com/BioinfoUNIBA/REDItools2 . CONCLUSIONS: HPC-REDItools is dramatically faster than the previous version, REDItools, enabling big-data analysis by means of a MPI-based implementation and scaling almost linearly with the number of available cores.


Assuntos
Metodologias Computacionais , Edição de RNA/genética , Software , Algoritmos , Sequência de Bases , Genoma , Transcriptoma/genética
8.
BMC Bioinformatics ; 21(Suppl 10): 352, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32838759

RESUMO

BACKGROUND: The advent of Next Generation Sequencing (NGS) technologies and the concomitant reduction in sequencing costs allows unprecedented high throughput profiling of biological systems in a cost-efficient manner. Modern biological experiments are increasingly becoming both data and computationally intensive and the wealth of publicly available biological data is introducing bioinformatics into the "Big Data" era. For these reasons, the effective application of High Performance Computing (HPC) architectures is becoming progressively more recognized also by bioinformaticians. Here we describe HPC resources provisioning pilot programs dedicated to bioinformaticians, run by the Italian Node of ELIXIR (ELIXIR-IT) in collaboration with CINECA, the main Italian supercomputing center. RESULTS: Starting from April 2016, CINECA and ELIXIR-IT launched the pilot Call "ELIXIR-IT HPC@CINECA", offering streamlined access to HPC resources for bioinformatics. Resources are made available either through web front-ends to dedicated workflows developed at CINECA or by providing direct access to the High Performance Computing systems through a standard command-line interface tailored for bioinformatics data analysis. This allows to offer to the biomedical research community a production scale environment, continuously updated with the latest available versions of publicly available reference datasets and bioinformatic tools. Currently, 63 research projects have gained access to the HPC@CINECA program, for a total handout of ~ 8 Millions of CPU/hours and, for data storage, ~ 100 TB of permanent and ~ 300 TB of temporary space. CONCLUSIONS: Three years after the beginning of the ELIXIR-IT HPC@CINECA program, we can appreciate its impact over the Italian bioinformatics community and draw some considerations. Several Italian researchers who applied to the program have gained access to one of the top-ranking public scientific supercomputing facilities in Europe. Those investigators had the opportunity to sensibly reduce computational turnaround times in their research projects and to process massive amounts of data, pursuing research approaches that would have been otherwise difficult or impossible to undertake. Moreover, by taking advantage of the wealth of documentation and training material provided by CINECA, participants had the opportunity to improve their skills in the usage of HPC systems and be better positioned to apply to similar EU programs of greater scale, such as PRACE. To illustrate the effective usage and impact of the resources awarded by the program - in different research applications - we report five successful use cases, which have already published their findings in peer-reviewed journals.


Assuntos
Biologia Computacional , Metodologias Computacionais , Software , Algoritmos , Animais , Linhagem Celular , Bases de Dados Genéticas , Fusão Gênica , Genoma , Humanos , Prunus persica/genética , Edição de RNA , Andorinhas/genética
9.
EMBO J ; 34(9): 1214-30, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25770584

RESUMO

Mammalian target of rapamycin (mTOR) is a key protein kinase that regulates cell growth, metabolism, and autophagy to maintain cellular homeostasis. Its activity is inhibited by adverse conditions, including nutrient limitation, hypoxia, and DNA damage. In this study, we demonstrate that Che-1, a RNA polymerase II-binding protein activated by the DNA damage response, inhibits mTOR activity in response to stress conditions. We found that, under stress, Che-1 induces the expression of two important mTOR inhibitors, Redd1 and Deptor, and that this activity is required for sustaining stress-induced autophagy. Strikingly, Che-1 expression correlates with the progression of multiple myeloma and is required for cell growth and survival, a malignancy characterized by high autophagy response.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Mieloma Múltiplo/patologia , Proteínas Repressoras/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos Nus , Mieloma Múltiplo/metabolismo , Complexos Multiproteicos/metabolismo , Fosforilação , Proteínas Repressoras/genética , Estresse Fisiológico , Serina-Treonina Quinases TOR/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
BMC Genomics ; 19(1): 120, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29402227

RESUMO

BACKGROUND: The advent and ongoing development of next generation sequencing technologies (NGS) has led to a rapid increase in the rate of human genome re-sequencing data, paving the way for personalized genomics and precision medicine. The body of genome resequencing data is progressively increasing underlining the need for accurate and time-effective bioinformatics systems for genotyping - a crucial prerequisite for identification of candidate causal mutations in diagnostic screens. RESULTS: Here we present CoVaCS, a fully automated, highly accurate system with a web based graphical interface for genotyping and variant annotation. Extensive tests on a gold standard benchmark data-set -the NA12878 Illumina platinum genome- confirm that call-sets based on our consensus strategy are completely in line with those attained by similar command line based approaches, and far more accurate than call-sets from any individual tool. Importantly our system exhibits better sensitivity and higher specificity than equivalent commercial software. CONCLUSIONS: CoVaCS offers optimized pipelines integrating state of the art tools for variant calling and annotation for whole genome sequencing (WGS), whole-exome sequencing (WES) and target-gene sequencing (TGS) data. The system is currently hosted at Cineca, and offers the speed of a HPC computing facility, a crucial consideration when large numbers of samples must be analysed. Importantly, all the analyses are performed automatically allowing high reproducibility of the results. As such, we believe that CoVaCS can be a valuable tool for the analysis of human genome resequencing studies. CoVaCS is available at: https://bioinformatics.cineca.it/covacs .


Assuntos
Biologia Computacional/métodos , Sequência Consenso , Análise de Sequência de DNA/métodos , Software , Algoritmos , Bases de Dados Genéticas , Mutação INDEL , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Sensibilidade e Especificidade , Interface Usuário-Computador , Navegador , Fluxo de Trabalho
11.
Plant Cell Physiol ; 59(1): e2, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29216377

RESUMO

Applying next-generation sequencing (NGS) technologies to species of agricultural interest has the potential to accelerate the understanding and exploration of genetic resources. The storage, availability and maintenance of huge quantities of NGS-generated data remains a major challenge. The PeachVar-DB portal, available at http://hpc-bioinformatics.cineca.it/peach, is an open-source catalog of genetic variants present in peach (Prunus persica L. Batsch) and wild-related species of Prunus genera, annotated from 146 samples publicly released on the Sequence Read Archive (SRA). We designed a user-friendly web-based interface of the database, providing search tools to retrieve single nucleotide polymorphism (SNP) and InDel variants, along with useful statistics and information. PeachVar-DB results are linked to the Genome Database for Rosaceae (GDR) and the Phytozome database to allow easy access to other external useful plant-oriented resources. In order to extend the genetic diversity covered by the PeachVar-DB further, and to allow increasingly powerful comparative analysis, we will progressively integrate newly released data.


Assuntos
Biologia Computacional/métodos , Variação Genética , Genoma de Planta/genética , Prunus persica/genética , Mineração de Dados/métodos , Bases de Dados Genéticas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Internet , Filogenia , Polimorfismo de Nucleotídeo Único , Prunus persica/classificação , Rosaceae/classificação , Rosaceae/genética
12.
J Cell Sci ; 129(8): 1671-84, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26945058

RESUMO

Collagen VI myopathies are genetic disorders caused by mutations in collagen 6 A1, A2 and A3 genes, ranging from the severe Ullrich congenital muscular dystrophy to the milder Bethlem myopathy, which is recapitulated by collagen-VI-null (Col6a1(-/-)) mice. Abnormalities in mitochondria and autophagic pathway have been proposed as pathogenic causes of collagen VI myopathies, but the link between collagen VI defects and these metabolic circuits remains unknown. To unravel the expression profiling perturbation in muscles with collagen VI myopathies, we performed a deep RNA profiling in both Col6a1(-/-)mice and patients with collagen VI pathology. The interactome map identified common pathways suggesting a previously undetected connection between circadian genes and collagen VI pathology. Intriguingly, Bmal1(-/-)(also known as Arntl) mice, a well-characterized model displaying arrhythmic circadian rhythms, showed profound deregulation of the collagen VI pathway and of autophagy-related genes. The involvement of circadian rhythms in collagen VI myopathies is new and links autophagy and mitochondrial abnormalities. It also opens new avenues for therapies of hereditary myopathies to modulate the molecular clock or potential gene-environment interactions that might modify muscle damage pathogenesis.


Assuntos
Fatores de Transcrição ARNTL/genética , Relógios Circadianos/fisiologia , Colágeno Tipo VI/genética , Contratura/genética , Mitocôndrias/fisiologia , Distrofias Musculares/congênito , Mutação/genética , Esclerose/genética , Animais , Autofagia/genética , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Knockout , Análise em Microsséries , Distrofias Musculares/genética , RNA/análise
13.
Cancer ; 123(2): 210-218, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27648926

RESUMO

BACKGROUND: Male breast cancer (MBC) is a rare disease whose etiology appears to be largely associated with genetic factors. BRCA1 and BRCA2 mutations account for about 10% of all MBC cases. Thus, a fraction of MBC cases are expected to be due to genetic factors not yet identified. To further explain the genetic susceptibility for MBC, whole-exome sequencing (WES) and targeted gene sequencing were applied to high-risk, BRCA1/2 mutation-negative MBC cases. METHODS: Germ-line DNA of 1 male and 2 female BRCA1/2 mutation-negative breast cancer (BC) cases from a pedigree showing a first-degree family history of MBC was analyzed with WES. Targeted gene sequencing for the validation of WES results was performed for 48 high-risk, BRCA1/2 mutation-negative MBC cases from an Italian multicenter study of MBC. A case-control series of 433 BRCA1/2 mutation-negative MBC and female breast cancer (FBC) cases and 849 male and female controls was included in the study. RESULTS: WES in the family identified the partner and localizer of BRCA2 (PALB2) c.419delA truncating mutation carried by the proband, her father, and her paternal uncle (all affected with BC) and the N-acetyltransferase 1 (NAT1) c.97C>T nonsense mutation carried by the proband's maternal aunt. Targeted PALB2 sequencing detected the c.1984A>T nonsense mutation in 1 of the 48 BRCA1/2 mutation-negative MBC cases. NAT1 c.97C>T was not found in the case-control series. CONCLUSIONS: These results add strength to the evidence showing that PALB2 is involved in BC risk for both sexes and indicate that consideration should be given to clinical testing of PALB2 for BRCA1/2 mutation-negative families with multiple MBC and FBC cases. Cancer 2017;123:210-218. © 2016 American Cancer Society.


Assuntos
Neoplasias da Mama Masculina/genética , Exoma/genética , Predisposição Genética para Doença/genética , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Estudos de Casos e Controles , Análise Mutacional de DNA/métodos , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Humanos , Itália , Masculino , Mutação/genética , Linhagem
14.
BMC Plant Biol ; 17(1): 192, 2017 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-29100531

RESUMO

BACKGROUND: Plum pox virus (PPV), agent of Sharka disease, is the most important quarantine pathogen of peach (P. persica L. Batsch). Extensive evaluation of peach germplasm has highlighted the lack of resistant sources, while suggesting the presence of a quantitative disease resistance, expressed as reduction in the intensity of symptoms. Unravelling the genetic architecture of peach response to PPV infection is essential for pyramiding resistant genes and for developing more tolerant varieties. For this purpose, a genome-wide association (GWA) approach was applied in a panel of accessions phenotyped for virus susceptibility and genotyped with the IPSC peach 9 K SNP Array, and coupled with an high-coverage resequencing of the tolerant accession 'Kamarat'. RESULTS: Genome-wide association identified three highly significant associated loci on chromosome 2 and 3, accounting for most of the reduction in PPV-M susceptibility within the analysed peach population. The exploration of associated intervals through whole-genome comparison of the tolerant accession 'Kamarat' and other susceptible accessions, including the PPV-resistant wild-related species P. davidiana, allow the identification of allelic variants in promising candidate genes, including an RTM2-like gene already characterized in A. thaliana. CONCLUSIONS: The present study is the first effort to identify genetic factors involved in Sharka disease in peach germplasm through a GWA approach. We provide evidence of the presence of quantitative resistant loci in a collection of peach accessions, identifying major loci and highly informative SNPs that could be useful for marker assisted selection. These results could serve as reference bases for future research aimed at the comprehension of genetic mechanism regulating the complex peach-PPV interaction.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/imunologia , Vírus Eruptivo da Ameixa/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Prunus persica/genética , Estudo de Associação Genômica Ampla , Genótipo , Fenótipo , Doenças das Plantas/virologia , Prunus persica/imunologia
15.
BMC Genomics ; 16: S3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26046471

RESUMO

BACKGROUND: The study of RNA has been dramatically improved by the introduction of Next Generation Sequencing platforms allowing massive and cheap sequencing of selected RNA fractions, also providing information on strand orientation (RNA-Seq). The complexity of transcriptomes and of their regulative pathways make RNA-Seq one of most complex field of NGS applications, addressing several aspects of the expression process (e.g. identification and quantification of expressed genes and transcripts, alternative splicing and polyadenylation, fusion genes and trans-splicing, post-transcriptional events, etc.). METHODS: In order to provide researchers with an effective and friendly resource for analyzing RNA-Seq data, we present here RAP (RNA-Seq Analysis Pipeline), a cloud computing web application implementing a complete but modular analysis workflow. This pipeline integrates both state-of-the-art bioinformatics tools for RNA-Seq analysis and in-house developed scripts to offer to the user a comprehensive strategy for data analysis. RAP is able to perform quality checks (adopting FastQC and NGS QC Toolkit), identify and quantify expressed genes and transcripts (with Tophat, Cufflinks and HTSeq), detect alternative splicing events (using SpliceTrap) and chimeric transcripts (with ChimeraScan). This pipeline is also able to identify splicing junctions and constitutive or alternative polyadenylation sites (implementing custom analysis modules) and call for statistically significant differences in genes and transcripts expression, splicing pattern and polyadenylation site usage (using Cuffdiff2 and DESeq). RESULTS: Through a user friendly web interface, the RAP workflow can be suitably customized by the user and it is automatically executed on our cloud computing environment. This strategy allows to access to bioinformatics tools and computational resources without specific bioinformatics and IT skills. RAP provides a set of tabular and graphical results that can be helpful to browse, filter and export analyzed data, according to the user needs.


Assuntos
RNA/análise , Análise de Sequência de RNA/métodos , Interface Usuário-Computador , Sequenciamento de Nucleotídeos em Larga Escala , Internet , Poliadenilação
16.
Nucleic Acids Res ; 41(Database issue): D125-31, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23118479

RESUMO

A comprehensive knowledge of all the factors involved in splicing, both proteins and RNAs, and of their interaction network is crucial for reaching a better understanding of this process and its functions. A large part of relevant information is buried in the literature or collected in various different databases. By hand-curated screenings of literature and databases, we retrieved experimentally validated data on 71 human RNA-binding splicing regulatory proteins and organized them into a database called 'SpliceAid-F' (http://www.caspur.it/SpliceAidF/). For each splicing factor (SF), the database reports its functional domains, its protein and chemical interactors and its expression data. Furthermore, we collected experimentally validated RNA-SF interactions, including relevant information on the RNA-binding sites, such as the genes where these sites lie, their genomic coordinates, the splicing effects, the experimental procedures used, as well as the corresponding bibliographic references. We also collected information from experiments showing no RNA-SF binding, at least in the assayed conditions. In total, SpliceAid-F contains 4227 interactions, 2590 RNA-binding sites and 1141 'no-binding' sites, including information on cellular contexts and conditions where binding was tested. The data collected in SpliceAid-F can provide significant information to explain an observed splicing pattern as well as the effect of mutations in functional regulatory elements.


Assuntos
Bases de Dados de Proteínas , Splicing de RNA , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sítios de Ligação , Humanos , Internet , Anotação de Sequência Molecular , Estrutura Terciária de Proteína , Precursores de RNA/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Interface Usuário-Computador
17.
Nucleic Acids Res ; 40(Database issue): D1168-72, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22123747

RESUMO

The MITOchondrial genome database of metaZOAns (MitoZoa) is a public resource for comparative analyses of metazoan mitochondrial genomes (mtDNA) at both the sequence and genomic organizational levels. The main characteristics of the MitoZoa database are the careful revision of mtDNA entry annotations and the possibility of retrieving gene order and non-coding region (NCR) data in appropriate formats. The MitoZoa retrieval system enables basic and complex queries at various taxonomic levels using different search menus. MitoZoa 2.0 has been enhanced in several aspects, including: a re-annotation pipeline to check the correctness of protein-coding gene predictions; a standardized annotation of introns and of precursor ORFs whose functionality is post-transcriptionally recovered by RNA editing or programmed translational frameshifting; updates of taxon-related fields and a BLAST sequence similarity search tool. Database novelties and the definition of standard mtDNA annotation rules, together with the user-friendly retrieval system and the BLAST service, make MitoZoa a valuable resource for comparative and evolutionary analyses as well as a reference database to assist in the annotation of novel mtDNA sequences. MitoZoa is freely accessible at http://www.caspur.it/mitozoa.


Assuntos
DNA Mitocondrial/química , Bases de Dados de Ácidos Nucleicos , Evolução Molecular , Genoma Mitocondrial , Mudança da Fase de Leitura do Gene Ribossômico , Genes Mitocondriais , Íntrons , Proteínas Mitocondriais/genética , Anotação de Sequência Molecular , Software
18.
Proc Natl Acad Sci U S A ; 108(33): 13710-5, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21807998

RESUMO

The transcription factor interferon regulatory factor 6 (IRF6) regulates craniofacial development and epidermal proliferation. We recently showed that IRF6 is a component of a regulatory feedback loop that controls the proliferative potential of epidermal cells. IRF6 is transcriptionally activated by p63 and induces its proteasome-mediated down-regulation, thereby limiting keratinocyte proliferative potential. We hypothesized that IRF6 may also be involved in skin carcinogenesis. Hence, we analyzed IRF6 expression in a large series of squamous cell carcinomas (SCCs) and found a strong down-regulation of IRF6 that correlated with tumor invasive and differentiation status. IRF6 down-regulation in SCC cell lines and primary tumors correlates with methylation on a CpG dinucleotide island located in its promoter region. To identify the molecular mechanisms regulating IRF6 potential tumor suppressive activity, we performed a genome-wide analysis by combining ChIP sequencing for IRF6 binding sites and gene expression profiling in primary human keratinocytes after siRNA-mediated IRF6 depletion. We observed dysregulation of cell cycle-related genes and genes involved in differentiation, cell adhesion, and cell-cell contact. Many of these genes were direct IRF6 targets. We also performed in vitro invasion assays showing that IRF6 down-regulation promotes invasive behavior and that reintroduction of IRF6 into SCC cells strongly inhibits cell growth. These results indicate a function for IRF6 in suppression of tumorigenesis in stratified epithelia.


Assuntos
Carcinoma de Células Escamosas/patologia , Regulação Neoplásica da Expressão Gênica , Fatores Reguladores de Interferon/fisiologia , Proteínas Supressoras de Tumor , Fenômenos Fisiológicos Celulares/genética , Proliferação de Células , Metilação de DNA , Humanos , Fatores Reguladores de Interferon/genética , Queratinócitos/patologia , Invasividade Neoplásica/genética , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
19.
Sci Data ; 11(1): 471, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724521

RESUMO

We present a de novo transcriptome of the mosquito vector Culex pipiens, assembled by sequences of susceptible and insecticide resistant larvae. The high quality of the assembly was confirmed by TransRate and BUSCO. A mapping percentage until 94.8% was obtained by aligning contigs to Nr, SwissProt, and TrEMBL, with 27,281 sequences that simultaneously mapped on the three databases. A total of 14,966 ORFs were also functionally annotated by using the eggNOG database. Among them, we identified ORF sequences of the main gene families involved in insecticide resistance. Therefore, this resource stands as a valuable reference for further studies of differential gene expression as well as to identify genes of interest for genetic-based control tools.


Assuntos
Culex , Resistência a Inseticidas , Larva , Transcriptoma , Animais , Culex/genética , Larva/genética , Larva/crescimento & desenvolvimento , Resistência a Inseticidas/genética , Mosquitos Vetores/genética , Fases de Leitura Aberta
20.
BMC Bioinformatics ; 14 Suppl 7: S11, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23815231

RESUMO

BACKGROUND: The advent of massively parallel sequencing technologies (Next Generation Sequencing, NGS) profoundly modified the landscape of human genetics.In particular, Whole Exome Sequencing (WES) is the NGS branch that focuses on the exonic regions of the eukaryotic genomes; exomes are ideal to help us understanding high-penetrance allelic variation and its relationship to phenotype. A complete WES analysis involves several steps which need to be suitably designed and arranged into an efficient pipeline.Managing a NGS analysis pipeline and its huge amount of produced data requires non trivial IT skills and computational power. RESULTS: Our web resource WEP (Whole-Exome sequencing Pipeline web tool) performs a complete WES pipeline and provides easy access through interface to intermediate and final results. The WEP pipeline is composed of several steps:1) verification of input integrity and quality checks, read trimming and filtering; 2) gapped alignment; 3) BAM conversion, sorting and indexing; 4) duplicates removal; 5) alignment optimization around insertion/deletion (indel) positions; 6) recalibration of quality scores; 7) single nucleotide and deletion/insertion polymorphism (SNP and DIP) variant calling; 8) variant annotation; 9) result storage into custom databases to allow cross-linking and intersections, statistics and much more. In order to overcome the challenge of managing large amount of data and maximize the biological information extracted from them, our tool restricts the number of final results filtering data by customizable thresholds, facilitating the identification of functionally significant variants. Default threshold values are also provided at the analysis computation completion, tuned with the most common literature work published in recent years. CONCLUSIONS: Through our tool a user can perform the whole analysis without knowing the underlying hardware and software architecture, dealing with both paired and single end data. The interface provides an easy and intuitive access for data submission and a user-friendly web interface for annotated variant visualization.Non-IT mastered users can access through WEP to the most updated and tested WES algorithms, tuned to maximize the quality of called variants while minimizing artifacts and false positives.The web tool is available at the following web address: http://www.caspur.it/wep.


Assuntos
Exoma , Sequenciamento de Nucleotídeos em Larga Escala , Software , Algoritmos , Humanos , Mutação INDEL , Internet , Polimorfismo de Nucleotídeo Único , Interface Usuário-Computador
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