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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38555475

RESUMO

The lack of interoperable data standards among reference genome data-sharing platforms inhibits cross-platform analysis while increasing the risk of data provenance loss. Here, we describe the FAIR bioHeaders Reference genome (FHR), a metadata standard guided by the principles of Findability, Accessibility, Interoperability and Reuse (FAIR) in addition to the principles of Transparency, Responsibility, User focus, Sustainability and Technology. The objective of FHR is to provide an extensive set of data serialisation methods and minimum data field requirements while still maintaining extensibility, flexibility and expressivity in an increasingly decentralised genomic data ecosystem. The effort needed to implement FHR is low; FHR's design philosophy ensures easy implementation while retaining the benefits gained from recording both machine and human-readable provenance.


Assuntos
Software , Humanos , Genoma , Genômica , Disseminação de Informação
2.
Microbiol Resour Announc ; 13(2): e0104523, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38289057

RESUMO

The ATCC Genome Portal (AGP, https://genomes.atcc.org/) is a database of authenticated genomes for bacteria, fungi, protists, and viruses held in ATCC's biorepository. It now includes 3,938 assemblies (253% increase) produced under ISO 9000 by ATCC. Here, we present new features and content added to the AGP for the research community.

3.
bioRxiv ; 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38076838

RESUMO

The lack of interoperable data standards among reference genome data-sharing platforms inhibits cross-platform analysis while increasing the risk of data provenance loss. Here, we describe the FAIR-bioHeaders Reference genome (FHR), a metadata standard guided by the principles of Findability, Accessibility, Interoperability, and Reuse (FAIR) in addition to the principles of Transparency, Responsibility, User focus, Sustainability, and Technology (TRUST). The objective of FHR is to provide an extensive set of data serialisation methods and minimum data field requirements while still maintaining extensibility, flexibility, and expressivity in an increasingly decentralised genomic data ecosystem. The effort needed to implement FHR is low; FHR's design philosophy ensures easy implementation while retaining the benefits gained from recording both machine and human-readable provenance.

4.
Endocrinology ; 164(12)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37944134

RESUMO

Functional human brown and white adipose tissue (BAT and WAT) are vital for thermoregulation and nutritional homeostasis, while obesity and other stressors lead, respectively, to cold intolerance and metabolic disease. Understanding BAT and WAT physiology and dysfunction necessitates clinical trials complemented by mechanistic experiments at the cellular level. These require standardized in vitro models, currently lacking, that establish references for gene expression and function. We generated and characterized a pair of immortalized, clonal human brown (hBA) and white (hWA) preadipocytes derived from the perirenal and subcutaneous depots, respectively, of a 40-year-old male individual. Cells were immortalized with hTERT and confirmed to be of a mesenchymal, nonhematopoietic lineage based on fluorescence-activated cell sorting and DNA barcoding. Functional assessments showed that the hWA and hBA phenocopied primary adipocytes in terms of adrenergic signaling, lipolysis, and thermogenesis. Compared to hWA, hBA were metabolically distinct, with higher rates of glucose uptake and lactate metabolism, and greater basal, maximal, and nonmitochondrial respiration, providing a mechanistic explanation for the association between obesity and BAT dysfunction. The hBA also responded to the stress of maximal respiration by using both endogenous and exogenous fatty acids. In contrast to certain mouse models, hBA adrenergic thermogenesis was mediated by several mechanisms, not principally via uncoupling protein 1 (UCP1). Transcriptomics via RNA-seq were consistent with the functional studies and established a molecular signature for each cell type before and after differentiation. These standardized cells are anticipated to become a common resource for future physiological, pharmacological, and genetic studies of human adipocytes.


Assuntos
Adipócitos Marrons , Tecido Adiposo Marrom , Masculino , Camundongos , Animais , Humanos , Adulto , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Obesidade/metabolismo , Tecido Adiposo Branco/metabolismo , Termogênese/genética , Adrenérgicos/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
5.
J Clin Pathol ; 77(1): 68-72, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37696594

RESUMO

The classification of haematological neoplasms recently underwent revision, generating two separate schemes-the International Consensus Classification and the fifth edition of the WHO classification. The new division into separate classification systems presents challenges for haematopathologists, haematologists/oncologists and patients. While it is too early to assess the full clinical impact, we sought to identify diagnostic discordance which may arise from applying separate classification schemes in myeloid neoplasia, and particularly in the challenging category of myelodysplastic syndrome/myeloproliferative neoplasms. A review of 64 such cases found 1 case with a significant discrepancy between the WHO and International Consensus Classification systems, and 9 cases with nominal discrepancies. Confusion from the use of conflicting diagnostic terms represents a potential source of patient harm, increased pathologist workload and burnout and erosion of clinician and patient trust.


Assuntos
Neoplasias Hematológicas , Síndromes Mielodisplásicas , Transtornos Mieloproliferativos , Humanos , Síndromes Mielodisplásicas/diagnóstico , Transtornos Mieloproliferativos/diagnóstico , Neoplasias Hematológicas/diagnóstico , Organização Mundial da Saúde
6.
Antimicrob Agents Chemother ; 66(7): e0005322, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35770999

RESUMO

Candida auris is an urgent antimicrobial resistance threat due to its global emergence, high mortality, and persistent transmissions. Nearly half of C. auris clinical and surveillance cases in the United States are from the New York and New Jersey Metropolitan area. We performed genome, and drug-resistance analysis of C. auris isolates from a patient who underwent multi-visceral transplantation. Whole-genome comparisons of 19 isolates, collected over 72 days, revealed closed similarity (Average Nucleotide Identity > 0.9996; Aligned Percentage > 0.9764) and a distinct subcluster of NY C. auris South Asia Clade I. All isolates had azole-linked resistance in ERG11(K143R) and CDR1(V704L). Echinocandin resistance first appeared with FKS1(S639Y) mutation and then a unique FKS1(F635C) mutation. Flucytosine-resistant isolates had mutations in FCY1, FUR1, and ADE17. Two pan-drug-resistant C. auris isolates had uracil phosphoribosyltransferase deletion (FUR1[1Δ33]) and the elimination of FUR1 expression, confirmed by a qPCR test developed in this study. Besides ERG11 mutations, four amphotericin B-resistant isolates showed no distinct nonsynonymous variants suggesting unknown genetic elements driving the resistance. Pan-drug-resistant C. auris isolates were not susceptible to two-drug antifungal combinations tested by checkerboard, Etest, and time-kill methods. The fungal population pattern, discerned from SNP phylogenetic analysis, was consistent with in-hospital or inpatient evolution of C. auris isolates circulating locally and not indicative of a recent introduction from elsewhere. The emergence of pan-drug-resistance to four major classes of antifungals in C. auris is alarming. Patients at high risk for drug-resistant C. auris might require novel therapeutic strategies and targeted pre-and/or posttransplant surveillance.


Assuntos
Antifúngicos , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Candida auris , Farmacorresistência Fúngica/genética , Humanos , Testes de Sensibilidade Microbiana , Filogenia
7.
Viruses ; 14(6)2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35746681

RESUMO

Early growth response 1 (EGR1) is an immediate early gene and transcription factor previously found to be significantly upregulated in human astrocytoma cells infected with Venezuelan equine encephalitis virus (VEEV). The loss of EGR1 resulted in decreased cell death but had no significant impact on viral replication. Here, we extend these studies to determine the impacts of EGR1 on gene expression following viral infection. Inflammatory genes CXCL3, CXCL8, CXCL10, TNF, and PTGS2 were upregulated in VEEV-infected cells, which was partially dependent on EGR1. Additionally, transcription factors, including EGR1 itself, as well as ATF3, FOS, JUN, KLF4, EGR2, and EGR4 were found to be partially transcriptionally dependent on EGR1. We also examined the role of EGR1 and the changes in gene expression in response to infection with other alphaviruses, including eastern equine encephalitis virus (EEEV), Sindbis virus (SINV), and chikungunya virus (CHIKV), as well as Zika virus (ZIKV) and Rift Valley fever virus (RVFV), members of the Flaviviridae and Phenuiviridae families, respectively. EGR1 was significantly upregulated to varying degrees in EEEV-, CHIKV-, RVFV-, SINV-, and ZIKV-infected astrocytoma cells. Genes that were identified as being partially transcriptionally dependent on EGR1 in infected cells included ATF3 (EEEV, CHIKV, ZIKV), JUN (EEEV), KLF4 (SINV, ZIKV, RVFV), CXCL3 (EEEV, CHIKV, ZIKV), CXCL8 (EEEV, CHIKV, ZIKV, RVFV), CXCL10 (EEEV, RVFV), TNF-α (EEEV, ZIKV, RVFV), and PTGS2 (EEEV, CHIKV, ZIKV). Additionally, inhibition of the inflammatory gene PTGS2 with Celecoxib, a small molecule inhibitor, rescued astrocytoma cells from VEEV-induced cell death but had no impact on viral titers. Collectively, these results suggest that EGR1 induction following viral infection stimulates multiple inflammatory mediators. Managing inflammation and cell death in response to viral infection is of utmost importance, especially during VEEV infection where survivors are at-risk for neurological sequalae.


Assuntos
Astrocitoma , Vírus da Encefalite Equina Venezuelana , Encefalomielite Equina , Infecção por Zika virus , Zika virus , Morte Celular , Ciclo-Oxigenase 2/genética , Proteína 1 de Resposta de Crescimento Precoce , Vírus da Encefalite Equina Venezuelana/genética , Humanos , Inflamação , Sindbis virus , Regulação para Cima
8.
mSphere ; 7(3): e0007722, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35491842

RESUMO

The availability of public genomics data has become essential for modern life sciences research, yet the quality, traceability, and curation of these data have significant impacts on a broad range of microbial genomics research. While microbial genome databases such as NCBI's RefSeq database leverage the scalability of crowd sourcing for growth, genomics data provenance and authenticity of the source materials used to produce data are not strict requirements. Here, we describe the de novo assembly of 1,113 bacterial genome references produced from authenticated materials sourced from the American Type Culture Collection (ATCC), each with full genomics data provenance relating to bioinformatics methods, quality control, and passage history. Comparative genomics analysis of ATCC standard reference genomes (ASRGs) revealed significant issues with regard to NCBI's RefSeq bacterial genome assemblies related to completeness, mutations, structure, strain metadata, and gaps in traceability to the original biological source materials. Nearly half of RefSeq assemblies lack details on sample source information, sequencing technology, or bioinformatics methods. Deep curation of these records is not within the scope of NCBI's core mission in supporting open science, which aims to collect sequence records that are submitted by the public. Nonetheless, we propose that gaps in metadata accuracy and data provenance represent an "elephant in the room" for microbial genomics research. Effectively addressing these issues will require raising the level of accountability for data depositors and acknowledging the need for higher expectations of quality among the researchers whose research depends on accurate and attributable reference genome data. IMPORTANCE The traceability of microbial genomics data to authenticated physical biological materials is not a requirement for depositing these data into public genome databases. This creates significant risks for the reliability and data provenance of these important genomics research resources, the impact of which is not well understood. We sought to investigate this by carrying out a comparative genomics study of 1,113 ATCC standard reference genomes (ASRGs) produced by ATCC from authenticated and traceable materials using the latest sequencing technologies. We found widespread discrepancies in genome assembly quality, genetic variability, and the quality and completeness of the associated metadata among hundreds of reference genomes for ATCC strains found in NCBI's RefSeq database. We present a comparative analysis of de novo-assembled ASRGs, their respective metadata, and variant analysis using RefSeq genomes as a reference. Although assembly quality in RefSeq has generally improved over time, we found that significant quality issues remain, especially as related to genomic data and metadata provenance. Our work highlights the importance of data authentication and provenance for the microbial genomics community, and underscores the risks of ignoring this issue in the future.


Assuntos
Bases de Dados Genéticas , Genômica , Genoma Bacteriano , Genoma Microbiano , Reprodutibilidade dos Testes
9.
Microbiol Resour Announc ; 10(47): e0081821, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817215

RESUMO

Lack of data provenance negatively impacts scientific reproducibility and the reliability of genomic data. The ATCC Genome Portal (https://genomes.atcc.org) addresses this by providing data provenance information for microbial whole-genome assemblies originating from authenticated biological materials. To date, we have sequenced 1,579 complete genomes, including 466 type strains and 1,156 novel genomes.

10.
Viruses ; 13(5)2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065980

RESUMO

Venezuelan equine encephalitis virus (VEEV) is an alphavirus that causes encephalitis. Previous work indicated that VEEV infection induced early growth response 1 (EGR1) expression, leading to cell death via the protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) arm of the unfolded protein response (UPR) pathway. Loss of PERK prevented EGR1 induction and decreased VEEV-induced death. The results presented within show that loss of PERK in human primary astrocytes dramatically reduced VEEV and eastern equine encephalitis virus (EEEV) infectious titers by 4-5 log10. Loss of PERK also suppressed VEEV replication in primary human pericytes and human umbilical vein endothelial cells, but it had no impact on VEEV replication in transformed U87MG and 293T cells. A significant reduction in VEEV RNA levels was observed as early as 3 h post-infection, but viral entry assays indicated that the loss of PERK minimally impacted VEEV entry. In contrast, the loss of PERK resulted in a dramatic reduction in viral nonstructural protein translation and negative-strand viral RNA production. The loss of PERK also reduced the production of Rift Valley fever virus and Zika virus infectious titers. These data indicate that PERK is an essential factor for the translation of alphavirus nonstructural proteins and impacts multiple RNA viruses, making it an exciting target for antiviral development.


Assuntos
Alphavirus/genética , Biossíntese de Proteínas , Proteínas não Estruturais Virais/genética , eIF-2 Quinase/genética , Alphavirus/classificação , Alphavirus/fisiologia , Astrócitos/metabolismo , Astrócitos/virologia , Morte Celular , Células Cultivadas , Vírus da Encefalite Equina Venezuelana/fisiologia , Células Endoteliais/metabolismo , Células Endoteliais/virologia , Células HEK293 , Humanos , Pericitos/metabolismo , Pericitos/virologia , RNA Viral/metabolismo , Resposta a Proteínas não Dobradas , Proteínas não Estruturais Virais/metabolismo , eIF-2 Quinase/metabolismo
12.
Virology ; 539: 121-128, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31733451

RESUMO

Venezuelan equine encephalitis virus (VEEV) is a neurotropic virus that causes significant disease in both humans and equines. Here we characterized the impact of VEEV on signaling pathways regulating cell death in human primary astrocytes. VEEV productively infected primary astrocytes and caused an upregulation of early growth response 1 (EGR1) gene expression at 9 and 18 h post infection. EGR1 induction was dependent on extracellular signal-regulated kinase1/2 (ERK1/2) and protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), but not on p38 mitogen activated protein kinase (MAPK) or phosphoinositide 3-kinase (PI3K) signaling. Knockdown of EGR1 significantly reduced VEEV-induced apoptosis and impacted viral replication. Knockdown of ERK1/2 or PERK significantly reduced EGR1 gene expression, dramatically reduced viral replication, and increased cell survival as well as rescued cells from VEEV-induced apoptosis. These data indicate that EGR1 activation and subsequent cell death are regulated through ERK and PERK pathways in VEEV infected primary astrocytes.


Assuntos
Morte Celular , Proteína 1 de Resposta de Crescimento Precoce/genética , Vírus da Encefalite Equina Venezuelana/fisiologia , Encefalomielite Equina Venezuelana/virologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , eIF-2 Quinase/metabolismo , Apoptose , Astrócitos/metabolismo , Astrócitos/patologia , Astrócitos/virologia , Sobrevivência Celular , Células Cultivadas , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Vírus da Encefalite Equina Venezuelana/patogenicidade , Encefalomielite Equina Venezuelana/metabolismo , Encefalomielite Equina Venezuelana/patologia , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Transdução de Sinais , Replicação Viral , eIF-2 Quinase/genética
13.
Sci Rep ; 8(1): 5417, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615665

RESUMO

The future of infectious disease surveillance and outbreak response is trending towards smaller hand-held solutions for point-of-need pathogen detection. Here, samples of Culex cedecei mosquitoes collected in Southern Florida, USA were tested for Venezuelan Equine Encephalitis Virus (VEEV), a previously-weaponized arthropod-borne RNA-virus capable of causing acute and fatal encephalitis in animal and human hosts. A single 20-mosquito pool tested positive for VEEV by quantitative reverse transcription polymerase chain reaction (RT-qPCR) on the Biomeme two3. The virus-positive sample was subjected to unbiased metatranscriptome sequencing on the Oxford Nanopore MinION and shown to contain Everglades Virus (EVEV), an alphavirus in the VEEV serocomplex. Our results demonstrate, for the first time, the use of unbiased sequence-based detection and subtyping of a high-consequence biothreat pathogen directly from an environmental sample using field-forward protocols. The development and validation of methods designed for field-based diagnostic metagenomics and pathogen discovery, such as those suitable for use in mobile "pocket laboratories", will address a growing demand for public health teams to carry out their mission where it is most urgent: at the point-of-need.


Assuntos
Biovigilância/métodos , Culex/virologia , Vírus da Encefalite Equina Venezuelana/classificação , Vírus da Encefalite Equina Venezuelana/genética , Nanoporos , Análise de Sequência de RNA/métodos , Animais , Vírus da Encefalite Equina Venezuelana/fisiologia , Filogenia
14.
J Virol ; 91(3)2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27852852

RESUMO

The alphaviruses Venezuelan equine encephalitis virus (VEEV), eastern equine encephalitis virus (EEEV), and western equine encephalitis virus (WEEV) are arthropod-borne positive-strand RNA viruses that are capable of causing acute and fatal encephalitis in many mammals, including humans. VEEV was weaponized during the Cold War and is recognized as a select agent. Currently, there are no FDA-approved vaccines or therapeutics for these viruses. The spread of VEEV and other members of this family due to climate change-mediated vector range expansion underscores the need for research aimed at developing medical countermeasures. These viruses utilize programmed -1 ribosomal frameshifting (-1 PRF) to synthesize the viral trans-frame (TF) protein, which has previously been shown to be important for neuropathogenesis in the related Sindbis virus. Here, the alphavirus -1 PRF signals were characterized, revealing novel -1 PRF stimulatory structures. -1 PRF attenuation mildly affected the kinetics of VEEV accumulation in cultured cells but strongly inhibited its pathogenesis in an aerosol infection mouse model. Importantly, the decreased viral titers in the brains of mice infected with the mutant virus suggest that the alphavirus TF protein is important for passage through the blood-brain barrier and/or for neuroinvasiveness. These findings suggest a novel approach to the development of safe and effective live attenuated vaccines directed against VEEV and perhaps other closely related -1 PRF-utilizing viruses. IMPORTANCE: Venezuelan equine encephalitis virus (VEEV) is a select agent that has been weaponized. This arthropod-borne positive-strand RNA virus causes acute and fatal encephalitis in many mammals, including humans. There is no vaccine or other approved therapeutic. VEEV and related alphaviruses utilize programmed -1 ribosomal frameshifting (-1 PRF) to synthesize the viral trans-frame (TF) protein, which is important for neuropathogenesis. -1 PRF attenuation strongly inhibited VEEV pathogenesis in mice, and viral replication analyses suggest that the TF protein is critical for neurological disease. These findings suggest a new approach to the development of safe and effective live attenuated vaccines directed against VEEV and other related viruses.


Assuntos
Vírus da Encefalite Equina Venezuelana/genética , Encefalomielite Equina Venezuelana/virologia , Mudança da Fase de Leitura do Gene Ribossômico , Animais , Linhagem Celular , Feminino , Genoma Viral , Cavalos , Humanos , Conformação de Ácido Nucleico , Fases de Leitura Aberta , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Viral , Replicação Viral
15.
Aorta (Stamford) ; 4(2): 64-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27757404

RESUMO

Anatomic anomalies of the aortic arch have implications for clinical practice if their significance is understood. Our case study involves a cadaveric finding of the left vertebral artery originating directly from the aortic arch. Although this anatomical variation has been documented, the prevalence of this anomaly may be generally underestimated. After noting this anomaly, we analyzed 27 cases and found that four female cadavers had the left vertebral artery originating from the aortic arch rather than the left subclavian artery. With a prevalence rate of 14.8%, it would seem that this anomaly is more significant than previously thought, which could have implications for surgical practice.

16.
J Virol ; 90(7): 3558-72, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26792742

RESUMO

UNLABELLED: Venezuelan equine encephalitis virus (VEEV) is a previously weaponized arthropod-borne virus responsible for causing acute and fatal encephalitis in animal and human hosts. The increased circulation and spread in the Americas of VEEV and other encephalitic arboviruses, such as eastern equine encephalitis virus and West Nile virus, underscore the need for research aimed at characterizing the pathogenesis of viral encephalomyelitis for the development of novel medical countermeasures. The host-pathogen dynamics of VEEV Trinidad donkey-infected human astrocytoma U87MG cells were determined by carrying out RNA sequencing (RNA-Seq) of poly(A) and mRNAs. To identify the critical alterations that take place in the host transcriptome following VEEV infection, samples were collected at 4, 8, and 16 h postinfection and RNA-Seq data were acquired using an Ion Torrent PGM platform. Differential expression of interferon response, stress response factors, and components of the unfolded protein response (UPR) was observed. The protein kinase RNA-like endoplasmic reticulum kinase (PERK) arm of the UPR was activated, as the expression of both activating transcription factor 4 (ATF4) and CHOP (DDIT3), critical regulators of the pathway, was altered after infection. Expression of the transcription factor early growth response 1 (EGR1) was induced in a PERK-dependent manner. EGR1(-/-) mouse embryonic fibroblasts (MEFs) demonstrated lower susceptibility to VEEV-induced cell death than isogenic wild-type MEFs, indicating that EGR1 modulates proapoptotic pathways following VEEV infection. The influence of EGR1 is of great importance, as neuronal damage can lead to long-term sequelae in individuals who have survived VEEV infection. IMPORTANCE: Alphaviruses represent a group of clinically relevant viruses transmitted by mosquitoes to humans. In severe cases, viral spread targets neuronal tissue, resulting in significant and life-threatening inflammation dependent on a combination of virus-host interactions. Currently there are no therapeutics for infections cause by encephalitic alphaviruses due to an incomplete understanding of their molecular pathogenesis. Venezuelan equine encephalitis virus (VEEV) is an alphavirus that is prevalent in the Americas and that is capable of infecting horses and humans. Here we utilized next-generation RNA sequencing to identify differential alterations in VEEV-infected astrocytes. Our results indicated that the abundance of transcripts associated with the interferon and the unfolded protein response pathways was altered following infection and demonstrated that early growth response 1 (EGR1) contributed to VEEV-induced cell death.


Assuntos
Apoptose , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Vírus da Encefalite Equina Venezuelana/fisiologia , Interações Hospedeiro-Patógeno , Resposta a Proteínas não Dobradas , Animais , Linhagem Celular , Proteína 1 de Resposta de Crescimento Precoce/genética , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Knockout
17.
Antiviral Res ; 112: 26-37, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25448087

RESUMO

Venezuelan equine encephalitis virus (VEEV) is classified as a Category B Select Agent and potential bioterror weapon for its severe disease course in humans and equines and its potential for aerosol transmission. There are no current FDA licensed vaccines or specific therapies against VEEV, making identification of potential therapeutic targets a priority. With this aim, our research focuses on the interactions of VEEV with host microRNA (miRNA) machinery. miRNAs are small non-coding RNAs that act as master regulators of gene expression by downregulating or degrading messenger RNA, thus suppressing production of the resultant proteins. Recent publications implicate miRNA interactions in the pathogenesis of various viral diseases. To test the importance of miRNA processing for VEEV replication, cells deficient in Ago2, an important component of the RNA-induced silencing complex (RISC), and cells treated with known Ago2 inhibitors, notably acriflavine (ACF), were utilized. Both conditions caused decreased viral replication and capsid expression. ACF treatment promoted increased survival of neuronal cells over a non-treated, infected control and reduced viral titers of fully virulent VEEV as well as Eastern and Western Equine Encephalitis Viruses and West Nile Virus, but not Vesicular Stomatitis Virus. ACF treatment of VEEV TC-83 infected mice resulted in increased in vivo survival, but did not affect survival or viral loads when mice were challenged with fully virulent VEEV TrD. These results suggest that inhibition of Ago2 results in decreased replication of encephalitic alphaviruses in vitro and this pathway may be an avenue to explore for future therapeutic development.


Assuntos
Antivirais/farmacologia , Proteínas Argonautas/antagonistas & inibidores , Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Vírus da Encefalite Equina Venezuelana/fisiologia , Inibidores Enzimáticos/farmacologia , Replicação Viral/efeitos dos fármacos , Acriflavina/farmacologia , Acriflavina/uso terapêutico , Animais , Antivirais/uso terapêutico , Proteínas do Capsídeo/biossíntese , Sobrevivência Celular , Modelos Animais de Doenças , Encefalomielite Equina Venezuelana/tratamento farmacológico , Encefalomielite Equina Venezuelana/virologia , Inibidores Enzimáticos/uso terapêutico , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Neurônios/fisiologia , Neurônios/virologia , Análise de Sobrevida , Resultado do Tratamento , Carga Viral
18.
BMC Genomics ; 9: 339, 2008 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-18637175

RESUMO

BACKGROUND: The Programmed Ribosomal Frameshift Database (PRFdb) provides an interface to help researchers identify potential programmed -1 ribosomal frameshift (-1 PRF) signals in eukaryotic genes or sequences of interest. RESULTS: To identify putative -1 PRF signals, sequences are first imported from whole genomes or datasets, e.g. the yeast genome project and mammalian gene collection. They are then filtered through multiple algorithms to identify potential -1 PRF signals as defined by a heptameric slippery site followed by an mRNA pseudoknot. The significance of each candidate -1 PRF signal is evaluated by comparing the predicted thermodynamic stability (DeltaG degrees ) of the native mRNA sequence against a distribution of DeltaG degrees values of a pool of randomized sequences derived from the original. The data have been compiled in a user-friendly, easily searchable relational database. CONCLUSION: The PRFdB enables members of the research community to determine whether genes that they are investigating contain potential -1 PRF signals, and can be used as a metasource of information for cross referencing with other databases. It is available on the web at http://dinmanlab.umd.edu/prfdb.


Assuntos
Sistemas de Gerenciamento de Base de Dados , Mudança da Fase de Leitura do Gene Ribossômico , Biologia Computacional , Internet , Interface Usuário-Computador
19.
Am J Pathol ; 172(2): 495-509, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18187569

RESUMO

Global genomic approaches in cancer research have provided new and innovative strategies for the identification of signatures that differentiate various types of human cancers. Computational analysis of the promoter composition of the genes within these signatures may provide a powerful method for deducing the regulatory transcriptional networks that mediate their collective function. In this study we have systematically analyzed the promoter composition of gene classes derived from previously established genetic signatures that recently have been shown to reliably and reproducibly distinguish five molecular subtypes of breast cancer associated with distinct clinical outcomes. Inferences made from the trends of transcription factor binding site enrichment in the promoters of these gene groups led to the identification of regulatory pathways that implicate discrete transcriptional networks associated with specific molecular subtypes of breast cancer. One of these inferred pathways predicted a role for nuclear factor-kappaB in a novel feed-forward, self-amplifying, autoregulatory module regulated by the ERBB family of growth factor receptors. The existence of this pathway was verified in vivo by chromatin immunoprecipitation and shown to be deregulated in breast cancer cells overexpressing ERBB2. This analysis indicates that approaches of this type can provide unique insights into the differential regulatory molecular programs associated with breast cancer and will aid in identifying specific transcriptional networks and pathways as potential targets for tumor subtype-specific therapeutic intervention.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Redes Reguladoras de Genes/genética , Regiões Promotoras Genéticas/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Análise por Conglomerados , Progressão da Doença , Feminino , Genes Neoplásicos , Humanos , Análise de Componente Principal
20.
Nucleic Acids Res ; 35(1): 165-74, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17158156

RESUMO

In viruses, programmed -1 ribosomal frameshifting (-1 PRF) signals direct the translation of alternative proteins from a single mRNA. Given that many basic regulatory mechanisms were first discovered in viral systems, the current study endeavored to: (i) identify -1 PRF signals in genomic databases, (ii) apply the protocol to the yeast genome and (iii) test selected candidates at the bench. Computational analyses revealed the presence of 10 340 consensus -1 PRF signals in the yeast genome. Of the 6353 yeast ORFs, 1275 contain at least one strong and statistically significant -1 PRF signal. Eight out of nine selected sequences promoted efficient levels of PRF in vivo. These findings provide a robust platform for high throughput computational and laboratory studies and demonstrate that functional -1 PRF signals are widespread in the genome of Saccharomyces cerevisiae. The data generated by this study have been deposited into a publicly available database called the PRFdb. The presence of stable mRNA pseudoknot structures in these -1 PRF signals, and the observation that the predicted outcomes of nearly all of these genomic frameshift signals would direct ribosomes to premature termination codons, suggest two possible mRNA destabilization pathways through which -1 PRF signals could post-transcriptionally regulate mRNA abundance.


Assuntos
Mudança da Fase de Leitura do Gene Ribossômico , Regulação Fúngica da Expressão Gênica , RNA Mensageiro/química , Sequências Reguladoras de Ácido Ribonucleico , Saccharomyces cerevisiae/genética , Sequência de Bases , Biologia Computacional , Interpretação Estatística de Dados , Bases de Dados de Ácidos Nucleicos , Genoma Fúngico , Genômica , Internet , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Fúngico/química
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