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1.
J Neurochem ; 168(4): 370-380, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36786545

RESUMEN

Millions of individuals globally suffer from inadvertent, occupational or self-harm exposures from organophosphate (OP) insecticides, significantly impacting human health. Similar to nerve agents, insecticides are neurotoxins that target and inhibit acetylcholinesterase (AChE) in central and peripheral synapses in the cholinergic nervous system. Post-exposure therapeutic countermeasures generally include administration of atropine with an oxime to reactivate the OP-inhibited AChE. However, animal model studies and recent clinical trials using insecticide-poisoned individuals have shown minimal clinical benefits of the currently approved oximes and their efficacy as antidotes has been debated. Currently used oximes either reactivate poorly, do not readily cross the blood-brain barrier (BBB), or are rapidly cleared from the circulation and must be repeatedly administered. Zwitterionic oximes of unbranched and simplified structure, for example RS194B, have been developed that efficiently cross the BBB resulting in reactivation of OP-inhibited AChE and dramatic reversal of severe clinical symptoms in mice and macaques exposed to OP insecticides or nerve agents. Thus, a single IM injection of RS194B has been shown to rapidly restore blood AChE and butyrylcholinesterase (BChE) activity, reverse cholinergic symptoms, and prevent death in macaques following lethal inhaled sarin and paraoxon exposure. The present macaque studies extend these findings and assess the ability of post-exposure RS194B treatment to counteract oral poisoning by highly toxic diethylphosphorothioate insecticides such as parathion and chlorpyrifos. These OPs require conversion by P450 in the liver of the inactive thions to the active toxic oxon forms, and once again demonstrated RS194B efficacy to reactivate and alleviate clinical symptoms within 60 mins of a single IM administration. Furthermore, when delivered orally, the Tmax of RS194B at 1-2 h was in the same range as those administered IM but were maintained in the circulation for longer periods greatly facilitating the use of RS194B as a non-invasive treatment, especially in isolated rural settings.


Asunto(s)
Acetamidas , Cloropirifos , Reactivadores de la Colinesterasa , Insecticidas , Agentes Nerviosos , Paratión , Animales , Ratones , Acetilcolinesterasa/química , Butirilcolinesterasa/química , Cloropirifos/toxicidad , Inhibidores de la Colinesterasa/química , Reactivadores de la Colinesterasa/química , Reactivadores de la Colinesterasa/farmacología , Insecticidas/toxicidad , Macaca , Compuestos Organofosforados/toxicidad , Oximas/farmacología , Oximas/química , Oximas/uso terapéutico , Paratión/efectos adversos , Paratión/toxicidad
2.
J Virol ; 95(18): e0026821, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34190597

RESUMEN

Preventing human immunodeficiency virus (HIV) infection in newborns by vertical transmission remains an important unmet medical need in resource-poor areas where antiretroviral therapy (ART) is not available and mothers and infants cannot be treated prepartum or during the breastfeeding period. In the present study, the protective efficacy of the potent HIV-neutralizing antibodies PGT121 and VRC07-523, both produced in plants, were assessed in a multiple-SHIV (simian-human immunodeficiency virus)-challenge breastfeeding macaque model. Newborn macaques received either six weekly subcutaneous injections with PGT121 alone or as a cocktail of PGT121-LS plus VRC07-523-LS injected three times every 2 weeks. Viral challenge with SHIVSF162P3 was twice weekly over 5.5 weeks using 11 exposures. Despite the transient presence of plasma viral RNA either immediately after the first challenge or as single-point blips, the antibodies prevented a productive infection in all babies with no sustained plasma viremia, compared to viral loads ranging from 103 to 5 × 108 virions/ml in four untreated controls. No virus was detected in peripheral blood mononuclear cells (PBMCs), and only 3 of 159 tissue samples were weakly positive in the treated babies. Newborn macaques proved to be immunocompetent, producing transient anti-Env antibodies and anti-drug antibody (ADA), which were maintained in the circulation after passive broadly neutralizing antibody clearance. ADA responses were directed to the IgG1 Fc CH2-CH3 domains, which has not been observed to date in adult monkeys passively treated with PGT121 or VRC01. In addition, high levels of VRC07-523 anti-idiotypic antibodies in the circulation of one newborn was concomitant with the rapid elimination of VRC07. Plant-expressed antibodies show promise as passive immunoprophylaxis in a breastfeeding model in newborns. IMPORTANCE Plant-produced human neutralizing antibody prophylaxis is highly effective in preventing infection in newborn monkeys during repeated oral exposure, modeling virus in breastmilk, and offers advantages in cost of production and safety. These findings raise the possibility that anti-Env antibodies may contribute to the control of viral replication in this newborn model and that the observed immune responsiveness may be driven by the long-lived presence of immune complexes.


Asunto(s)
Lactancia Materna , Anticuerpos ampliamente neutralizantes/inmunología , VIH-1/fisiología , Inmunización Pasiva/métodos , Nicotiana/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/terapia , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Animales Recién Nacidos , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/terapia , Infecciones por VIH/virología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/virología , Macaca mulatta , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Nicotiana/virología , Viremia/inmunología , Viremia/terapia , Viremia/virología
3.
PLoS Comput Biol ; 17(3): e1008708, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33651795

RESUMEN

Alternative splicing can expand the diversity of proteomes. Homologous mutually exclusive exons (MXEs) originate from the same ancestral exon and result in polypeptides with similar structural properties but altered sequence. Why would some genes switch homologous exons and what are their biological impact? Here, we analyse the extent of sequence, structural and functional variability in MXEs and report the first large scale, structure-based analysis of the biological impact of MXE events from different genomes. MXE-specific residues tend to map to single domains, are highly enriched in surface exposed residues and cluster at or near protein functional sites. Thus, MXE events are likely to maintain the protein fold, but alter specificity and selectivity of protein function. This comprehensive resource of MXE events and their annotations is available at: http://gene3d.biochem.ucl.ac.uk/mxemod/. These findings highlight how small, but significant changes at critical positions on a protein surface are exploited in evolution to alter function.


Asunto(s)
Empalme Alternativo/genética , Exones/genética , Genoma/genética , Proteínas , Animales , Evolución Molecular , Genómica , Humanos , Proteínas/genética , Proteínas/fisiología
4.
Nucleic Acids Res ; 47(6): 2807-2821, 2019 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-30649516

RESUMEN

Epstein-Barr virus proteins EBNA3A, EBNA3B and EBNA3C control hundreds of host genes after infection. Changes in epigenetic marks around EBNA3-regulated genes suggest that they exert transcriptional control in collaboration with epigenetic factors. The roles of polycomb repressive complex (PRC)2 subunit SUZ12 and of PRC1 subunit BMI1 were assessed for their importance in EBNA3-mediated repression and activation. ChIP-seq experiments for SUZ12 and BMI1 were performed to determine their global localization on chromatin and analysis offered further insight into polycomb protein distribution in differentiated cells. Their localization was compared to that of each EBNA3 to resolve longstanding questions about the EBNA3-polycomb relationship. SUZ12 did not co-localize with any EBNA3, whereas EBNA3C co-localized significantly and co-immunoprecipitated with BMI1. In cells expressing a conditional EBNA3C, BMI1 was sequestered to EBNA3C-binding sites after EBNA3C activation. When SUZ12 or BMI1 was knocked down in the same cells, SUZ12 did not contribute to EBNA3C-mediated regulation. Surprisingly, after BMI1 knockdown, EBNA3C repressed equally efficiently but host gene activation by EBNA3C was impaired. This overturns previous assumptions about BMI1/PRC1 functions during EBNA3C-mediated regulation, for the first time identifies directly a host factor involved in EBNA3-mediated activation and provides a new insight into how PRC1 can be involved in gene activation.


Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr/fisiología , Interacciones Huésped-Patógeno/genética , Complejo Represivo Polycomb 1/fisiología , Activación Transcripcional , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/metabolismo , Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HEK293 , Herpesvirus Humano 4/fisiología , Humanos , Complejo Represivo Polycomb 1/metabolismo , Unión Proteica
5.
Nucleic Acids Res ; 47(D1): D280-D284, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30398663

RESUMEN

This article provides an update of the latest data and developments within the CATH protein structure classification database (http://www.cathdb.info). The resource provides two levels of release: CATH-B, a daily snapshot of the latest structural domain boundaries and superfamily assignments, and CATH+, which adds layers of derived data, such as predicted sequence domains, functional annotations and functional clustering (known as Functional Families or FunFams). The most recent CATH+ release (version 4.2) provides a huge update in the coverage of structural data. This release increases the number of fully- classified domains by over 40% (from 308 999 to 434 857 structural domains), corresponding to an almost two- fold increase in sequence data (from 53 million to over 95 million predicted domains) organised into 6119 superfamilies. The coverage of high-resolution, protein PDB chains that contain at least one assigned CATH domain is now 90.2% (increased from 82.3% in the previous release). A number of highly requested features have also been implemented in our web pages: allowing the user to view an alignment between their query sequence and a representative FunFam structure and providing tools that make it easier to view the full structural context (multi-domain architecture) of domains and chains.


Asunto(s)
Bases de Datos de Proteínas , Genoma , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Ontología de Genes , Humanos , Modelos Moleculares , Anotación de Secuencia Molecular , Familia de Multigenes/genética , Conformación Proteica , Dominios Proteicos/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad
6.
J Acoust Soc Am ; 149(3): 1796, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33765803

RESUMEN

While studies of urban acoustics are typically restricted to the audio range, anthropogenic activity also generates infrasound (<20 Hz, roughly at the lower end of the range of human hearing). Shutdowns related to the COVID-19 pandemic unintentionally created ideal conditions for the study of urban infrasound and low frequency audio (20-500 Hz), as closures reduced human-generated ambient noise, while natural signals remained relatively unaffected. An array of infrasound sensors deployed in Las Vegas, NV, provides data for a case study in monitoring human activity during the pandemic through urban acoustics. The array records a sharp decline in acoustic power following the temporary shutdown of businesses deemed nonessential by the state of Nevada. This decline varies spatially across the array, with stations close to McCarran International Airport generally recording the greatest declines in acoustic power. Further, declines in acoustic power fluctuate with the time of day. As only signals associated with anthropogenic activity are expected to decline, this gives a rough indication of periodicities in urban acoustics throughout Las Vegas. The results of this study reflect the city's response to the pandemic and suggest spatiotemporal trends in acoustics outside of shutdowns.


Asunto(s)
Acústica/instrumentación , COVID-19/prevención & control , Monitoreo del Ambiente , Actividades Humanas , Ciudades , Control de Enfermedades Transmisibles , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Humanos , Nevada , Ruido , Pandemias , SARS-CoV-2
7.
Nucleic Acids Res ; 46(D1): D435-D439, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29112716

RESUMEN

Gene3D (http://gene3d.biochem.ucl.ac.uk) is a database of globular domain annotations for millions of available protein sequences. Gene3D has previously featured in the Database issue of NAR and here we report a significant update to the Gene3D database. The current release, Gene3D v16, has significantly expanded its domain coverage over the previous version and now contains over 95 million domain assignments. We also report a new method for dealing with complex domain architectures that exist in Gene3D, arising from discontinuous domains. Amongst other updates, we have added visualization tools for exploring domain annotations in the context of other sequence features and in gene families. We also provide web-pages to visualize other domain families that co-occur with a given query domain family.


Asunto(s)
Bases de Datos de Proteínas , Genoma , Dominios Proteicos , Proteínas/química , Programas Informáticos , Secuencia de Aminoácidos , Animales , Gráficos por Computador , Humanos , Internet , Anotación de Secuencia Molecular , Proteínas/genética , Proteínas/metabolismo , Análisis de Secuencia de Proteína
8.
J Proteome Res ; 18(6): 2525-2534, 2019 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-31083952

RESUMEN

An important area of modern biology consists of understanding the relationship between genotype and phenotype. However, to understand this relationship it is essential to investigate one of the principal links between them: the proteome. With the development of recent mass-spectrometry approaches, it is now possible to quantify entire proteomes and thus relate them to different phenotypes. Here, we present a comparison of the proteome of two extreme developmental states in the well-established model organism Drosophila melanogaster: adult and embryo. Protein modules such as ribosome, proteasome, tricarboxylic acid cycle, glycolysis, or oxidative phosphorylation were found differentially expressed between the two developmental stages. Analysis of post-translation modifications of the proteins identified in this study indicates that they generally follow the same trend as their corresponding protein. Comparison between changes in the proteome and the transcriptome highlighted patterns of post-transcriptional regulation for the subunits of protein complexes such as the ribosome and the proteasome, whereas protein from modules such as TCA cycle, glycolysis, and oxidative phosphorylation seem to be coregulated at the transcriptional level. Finally, the impact of the endosymbiont Wolbachia pipientis on the proteome of both developmental states was also investigated.


Asunto(s)
Drosophila melanogaster/genética , Biosíntesis de Proteínas/genética , Proteoma/genética , Transcriptoma/genética , Animales , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/microbiología , Embrión no Mamífero/metabolismo , Embrión no Mamífero/microbiología , Regulación del Desarrollo de la Expresión Génica/genética , Proteolisis , Proteoma/metabolismo , Proteómica/métodos , Wolbachia/patogenicidad
9.
Nucleic Acids Res ; 45(D1): D289-D295, 2017 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-27899584

RESUMEN

The latest version of the CATH-Gene3D protein structure classification database has recently been released (version 4.1, http://www.cathdb.info). The resource comprises over 300 000 domain structures and over 53 million protein domains classified into 2737 homologous superfamilies, doubling the number of predicted protein domains in the previous version. The daily-updated CATH-B, which contains our very latest domain assignment data, provides putative classifications for over 100 000 additional protein domains. This article describes developments to the CATH-Gene3D resource over the last two years since the publication in 2015, including: significant increases to our structural and sequence coverage; expansion of the functional families in CATH; building a support vector machine (SVM) to automatically assign domains to superfamilies; improved search facilities to return alignments of query sequences against multiple sequence alignments; the redesign of the web pages and download site.


Asunto(s)
Biología Computacional/métodos , Bases de Datos de Proteínas , Modelos Moleculares , Proteínas/química , Proteínas/metabolismo , Programas Informáticos , Relación Estructura-Actividad , Navegador Web
10.
Nucleic Acids Res ; 45(5): 2368-2383, 2017 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-27903901

RESUMEN

ChIP-seq performed on lymphoblastoid cell lines (LCLs), expressing epitope-tagged EBNA3A, EBNA3B or EBNA3C from EBV-recombinants, revealed important principles of EBNA3 binding to chromatin. When combined with global chromatin looping data, EBNA3-bound loci were found to have a singular character, each directly associating with either EBNA3-repressed or EBNA3-activated genes, but not with both. EBNA3A and EBNA3C showed significant association with repressed and activated genes. Significant direct association for EBNA3B loci could only be shown with EBNA3B-repressed genes. A comparison of EBNA3 binding sites with known transcription factor binding sites in LCL GM12878 revealed substantial co-localization of EBNA3s with RUNX3-a protein induced by EBV during B cell transformation. The beta-subunit of core binding factor (CBFß), that heterodimerizes with RUNX3, could co-immunoprecipitate robustly EBNA3B and EBNA3C, but only weakly EBNA3A. Depletion of either RUNX3 or CBFß with lentivirus-delivered shRNA impaired epitope-tagged EBNA3B and EBNA3C binding at multiple regulated gene loci, indicating a requirement for CBF heterodimers in EBNA3 recruitment during target-gene regulation. ShRNA-mediated depletion of CBFß in an EBNA3C-conditional LCL confirmed the role of CBF in the regulation of EBNA3C-induced and -repressed genes. These results reveal an important role for RUNX3/CBF during B cell transformation and EBV latency that was hitherto unexplored.


Asunto(s)
Factores de Unión al Sitio Principal/metabolismo , Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Regulación de la Expresión Génica , Sitios de Unión , Línea Celular , Cromatina/química , Cromatina/metabolismo , Inmunoprecipitación de Cromatina , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Subunidad alfa 3 del Factor de Unión al Sitio Principal/fisiología , Subunidad beta del Factor de Unión al Sitio Principal/metabolismo , Factores de Unión al Sitio Principal/fisiología , Elementos de Facilitación Genéticos , Genoma Humano , Humanos , Factores de Transcripción/metabolismo , Sitio de Iniciación de la Transcripción
11.
PLoS Comput Biol ; 13(10): e1005791, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29045400

RESUMEN

Accurate gene or protein function prediction is a key challenge in the post-genome era. Most current methods perform well on molecular function prediction, but struggle to provide useful annotations relating to biological process functions due to the limited power of sequence-based features in that functional domain. In this work, we systematically evaluate the predictive power of temporal transcription expression profiles for protein function prediction in Drosophila melanogaster. Our results show significantly better performance on predicting protein function when transcription expression profile-based features are integrated with sequence-derived features, compared with the sequence-derived features alone. We also observe that the combination of expression-based and sequence-based features leads to further improvement of accuracy on predicting all three domains of gene function. Based on the optimal feature combinations, we then propose a novel multi-classifier-based function prediction method for Drosophila melanogaster proteins, FFPred-fly+. Interpreting our machine learning models also allows us to identify some of the underlying links between biological processes and developmental stages of Drosophila melanogaster.


Asunto(s)
Biología Computacional/métodos , Proteínas de Drosophila/genética , Drosophila melanogaster/crecimiento & desarrollo , Perfilación de la Expresión Génica/métodos , Transcriptoma/genética , Animales , Análisis por Conglomerados , Simulación por Computador , Proteínas de Drosophila/análisis , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Modelos Estadísticos , Fenotipo , Transcriptoma/fisiología
12.
Nucleic Acids Res ; 44(D1): D404-9, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26578585

RESUMEN

Gene3D http://gene3d.biochem.ucl.ac.uk is a database of domain annotations of Ensembl and UniProtKB protein sequences. Domains are predicted using a library of profile HMMs representing 2737 CATH superfamilies. Gene3D has previously featured in the Database issue of NAR and here we report updates to the website and database. The current Gene3D (v14) release has expanded its domain assignments to ∼ 20,000 cellular genomes and over 43 million unique protein sequences, more than doubling the number of protein sequences since our last publication. Amongst other updates, we have improved our Functional Family annotation method. We have also improved the quality and coverage of our 3D homology modelling pipeline of predicted CATH domains. Additionally, the structural models have been expanded to include an extra model organism (Drosophila melanogaster). We also document a number of additional visualization tools in the Gene3D website.


Asunto(s)
Bases de Datos de Proteínas , Estructura Terciaria de Proteína , Humanos , Internet , Modelos Moleculares , Anotación de Secuencia Molecular , Dominios y Motivos de Interacción de Proteínas , Estructura Terciaria de Proteína/genética
13.
Sensors (Basel) ; 18(3)2018 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-29562691

RESUMEN

A miniaturized 2.4 GHz re-entrant cavity has been designed, manufactured and tested as a sensor for microfluidic compositional analysis. It has been fully evaluated experimentally with water and common solvents, namely methanol, ethanol, and chloroform, with excellent agreement with the expected behaviour predicted by the Debye model. The sensor's performance has also been assessed for analysis of segmented flow using water and oil. The samples' interaction with the electric field in the gap region has been maximized by aligning the sample tube parallel to the electric field in this region, and the small width of the gap (typically 1 mm) result in a highly localised complex permittivity measurement. The re-entrant cavity has simple mechanical geometry, small size, high quality factor, and due to the high concentration of electric field in the gap region, a very small mode volume. These factors combine to result in a highly sensitive, compact sensor for both pure liquids and liquid mixtures in capillary or microfluidic environments.

14.
Nucleic Acids Res ; 43(W1): W148-53, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25964299

RESUMEN

The widening function annotation gap in protein databases and the increasing number and diversity of the proteins being sequenced presents new challenges to protein function prediction methods. Multidomain proteins complicate the protein sequence-structure-function relationship further as new combinations of domains can expand the functional repertoire, creating new proteins and functions. Here, we present the FunFHMMer web server, which provides Gene Ontology (GO) annotations for query protein sequences based on the functional classification of the domain-based CATH-Gene3D resource. Our server also provides valuable information for the prediction of functional sites. The predictive power of FunFHMMer has been validated on a set of 95 proteins where FunFHMMer performs better than BLAST, Pfam and CDD. Recent validation by an independent international competition ranks FunFHMMer as one of the top function prediction methods in predicting GO annotations for both the Biological Process and Molecular Function Ontology. The FunFHMMer web server is available at http://www.cathdb.info/search/by_funfhmmer.


Asunto(s)
Anotación de Secuencia Molecular , Estructura Terciaria de Proteína , Programas Informáticos , Ontología de Genes , Internet , Proteínas/clasificación , Proteínas/genética , Proteínas/fisiología
15.
Nucleic Acids Res ; 43(Database issue): D376-81, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25348408

RESUMEN

The latest version of the CATH-Gene3D protein structure classification database (4.0, http://www.cathdb.info) provides annotations for over 235,000 protein domain structures and includes 25 million domain predictions. This article provides an update on the major developments in the 2 years since the last publication in this journal including: significant improvements to the predictive power of our functional families (FunFams); the release of our 'current' putative domain assignments (CATH-B); a new, strictly non-redundant data set of CATH domains suitable for homology benchmarking experiments (CATH-40) and a number of improvements to the web pages.


Asunto(s)
Bases de Datos de Proteínas , Anotación de Secuencia Molecular , Estructura Terciaria de Proteína , Genómica , Internet , Estructura Terciaria de Proteína/genética , Proteínas/clasificación
16.
Bioinformatics ; 31(21): 3460-7, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26139634

RESUMEN

MOTIVATION: Computational approaches that can predict protein functions are essential to bridge the widening function annotation gap especially since <1.0% of all proteins in UniProtKB have been experimentally characterized. We present a domain-based method for protein function classification and prediction of functional sites that exploits functional sub-classification of CATH superfamilies. The superfamilies are sub-classified into functional families (FunFams) using a hierarchical clustering algorithm supervised by a new classification method, FunFHMMer. RESULTS: FunFHMMer generates more functionally coherent groupings of protein sequences than other domain-based protein classifications. This has been validated using known functional information. The conserved positions predicted by the FunFams are also found to be enriched in known functional residues. Moreover, the functional annotations provided by the FunFams are found to be more precise than other domain-based resources. FunFHMMer currently identifies 110,439 FunFams in 2735 superfamilies which can be used to functionally annotate>16 million domain sequences. AVAILABILITY AND IMPLEMENTATION: All FunFam annotation data are made available through the CATH webpages (http://www.cathdb.info). The FunFHMMer webserver (http://www.cathdb.info/search/by_funfhmmer) allows users to submit query sequences for assignment to a CATH FunFam. CONTACT: sayoni.das.12@ucl.ac.uk SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Algoritmos , Bases de Datos de Proteínas , Anotación de Secuencia Molecular , Estructura Terciaria de Proteína , Proteínas/química , Proteínas/clasificación , Secuencia de Aminoácidos , Humanos , Datos de Secuencia Molecular , Proteínas/genética , Proteínas/metabolismo , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido , Homología Estructural de Proteína
17.
Bioinformatics ; 31(12): 2052-3, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25667547

RESUMEN

MOTIVATION: Most biological processes remain only partially characterized with many components still to be identified. Given that a whole genome can usually not be tested in a functional assay, identifying the genes most likely to be of interest is of critical importance to avoid wasting resources. RESULTS: Given a set of known functionally related genes and using a state-of-the-art approach to data integration and mining, our Functional Lists (FUN-L) method provides a ranked list of candidate genes for testing. Validation of predictions from FUN-L with independent RNAi screens confirms that FUN-L-produced lists are enriched in genes with the expected phenotypes. In this article, we describe a website front end to FUN-L. AVAILABILITY AND IMPLEMENTATION: The website is freely available to use at http://funl.org


Asunto(s)
Algoritmos , Biología Computacional/métodos , Minería de Datos/métodos , Redes Reguladoras de Genes , Interferencia de ARN , Programas Informáticos , Humanos , Fenotipo
18.
Nucleic Acids Res ; 42(Database issue): D240-5, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24270792

RESUMEN

Gene3D (http://gene3d.biochem.ucl.ac.uk) is a database of protein domain structure annotations for protein sequences. Domains are predicted using a library of profile HMMs from 2738 CATH superfamilies. Gene3D assigns domain annotations to Ensembl and UniProt sequence sets including >6000 cellular genomes and >20 million unique protein sequences. This represents an increase of 45% in the number of protein sequences since our last publication. Thanks to improvements in the underlying data and pipeline, we see large increases in the domain coverage of sequences. We have expanded this coverage by integrating Pfam and SUPERFAMILY domain annotations, and we now resolve domain overlaps to provide highly comprehensive composite multi-domain architectures. To make these data more accessible for comparative genome analyses, we have developed novel search algorithms for searching genomes to identify related multi-domain architectures. In addition to providing domain family annotations, we have now developed a pipeline for 3D homology modelling of domains in Gene3D. This has been applied to the human genome and will be rolled out to other major organisms over the next year.


Asunto(s)
Bases de Datos de Proteínas , Anotación de Secuencia Molecular , Estructura Terciaria de Proteína , Genoma , Genómica , Internet , Modelos Moleculares , Estructura Terciaria de Proteína/genética , Análisis de Secuencia de Proteína
19.
BMC Genomics ; 16: 608, 2015 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-26275604

RESUMEN

BACKGROUND: In complex Metazoans a given gene frequently codes for multiple protein isoforms, through processes such as alternative splicing. Large scale functional annotation of these isoforms is a key challenge for functional genomics. This annotation gap is increasing with the large numbers of multi transcript genes being identified by technologies such as RNASeq. Furthermore attempts to characterise the functions of splicing in an organism are complicated by the difficulty in distinguishing functional isoforms from those produced by splicing errors or transcription noise. Tools to help prioritise candidate isoforms for testing are largely absent. RESULTS: In this study we implement a Time-course Switch (TS) score for ranking isoforms by their likelihood of producing additional functions based on their developmental expression profiles, as reported by modENCODE. The TS score allows us to better investigate functional roles of different isoforms expressed in multi transcript genes. From this analysis, we find that isoforms with high TS scores have sequence feature changes consistent with more deterministic splicing and functional changes and tend to gain domains or whole exons which could carry additional functions. Furthermore these functions appear to be particularly important for essential regulatory roles, establishing functional isoform switching as key for regulatory processes. Based on the TS score we develop a Transcript Annotations Pipeline for Alternative Splicing (TAPAS) that identifies functional neighbourhoods of potentially interesting isoforms. CONCLUSIONS: We have identified a subset of protein isoforms which appear to have high functional significance, particularly in regulation. This has been made possible through the development of novel methods that make use of transcript expression profiles. The methods and analyses we present here represent important first steps in the development of tools to address the near complete lack of isoform specific function annotation. In turn the tools allow us to better characterise the regulatory functions of alternative splicing in more detail.


Asunto(s)
Empalme Alternativo , Drosophila melanogaster/crecimiento & desarrollo , Isoformas de Proteínas/metabolismo , Algoritmos , Animales , Biología Computacional/métodos , Bases de Datos Genéticas , Drosophila melanogaster/genética , Regulación del Desarrollo de la Expresión Génica , ARN Mensajero/metabolismo
20.
Antimicrob Agents Chemother ; 59(1): 407-13, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25367910

RESUMEN

We previously reported the development of a prototype antibiotic sensitivity assay to detect drug-resistant Mycobacterium tuberculosis using infection by mycobacteriophage to create a novel nucleic acid transcript, a surrogate marker of mycobacterial viability, detected by reverse transcriptase PCR (M. C. Mulvey et al., mBio 3: e00312-11, 2012). This assay detects antibiotic resistance to all drugs, even drugs for which the resistance mechanism is unknown or complex: it is a phenotypic readout using nucleic acid detection. In this report, we describe development and characteristics of an optimized reporter system that directed expression of the RNA cyclase ribozyme, which generated circular RNA through an intramolecular splicing reaction and led to accumulation of a new nucleic acid sequence in phage-infected bacteria. These modifications simplified the assay, increased the limit of detection from 10(4) to <10(2) M. tuberculosis cells, and correctly identified the susceptibility profile of M. tuberculosis strains exposed for 16 h to either first-line or second-line antitubercular drugs. In addition to phenotypic drug resistance or susceptibility, the assay reported streptomycin MICs and clearly detected 10% drug-resistant cells in an otherwise drug-susceptible population.


Asunto(s)
Antituberculosos/farmacología , ARN Polimerasas Dirigidas por ADN/genética , Pruebas de Sensibilidad Microbiana/métodos , Mycobacterium tuberculosis/efectos de los fármacos , ARN Polimerasas Dirigidas por ADN/biosíntesis , Farmacorresistencia Bacteriana Múltiple/genética , Genes Reporteros/genética , Micobacteriófagos/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/virología , ARN/genética , ARN Circular , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología
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