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1.
Mol Syst Biol ; 19(5): e11361, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36919946

RESUMO

DNA methylation comprises a cumulative record of lifetime exposures superimposed on genetically determined markers. Little is known about methylation dynamics in humans following an acute perturbation, such as infection. We characterized the temporal trajectory of blood epigenetic remodeling in 133 participants in a prospective study of young adults before, during, and after asymptomatic and mildly symptomatic SARS-CoV-2 infection. The differential methylation caused by asymptomatic or mildly symptomatic infections was indistinguishable. While differential gene expression largely returned to baseline levels after the virus became undetectable, some differentially methylated sites persisted for months of follow-up, with a pattern resembling autoimmune or inflammatory disease. We leveraged these responses to construct methylation-based machine learning models that distinguished samples from pre-, during-, and postinfection time periods, and quantitatively predicted the time since infection. The clinical trajectory in the young adults and in a diverse cohort with more severe outcomes was predicted by the similarity of methylation before or early after SARS-CoV-2 infection to the model-defined postinfection state. Unlike the phenomenon of trained immunity, the postacute SARS-CoV-2 epigenetic landscape we identify is antiprotective.


Assuntos
COVID-19 , Adulto Jovem , Humanos , COVID-19/genética , SARS-CoV-2/genética , Estudos Prospectivos , Metilação de DNA/genética , Processamento de Proteína Pós-Traducional
2.
Immunity ; 43(3): 605-14, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26362267

RESUMO

Many functionally important interactions between genes and proteins involved in immunological diseases and processes are unknown. The exponential growth in public high-throughput data offers an opportunity to expand this knowledge. To unlock human-immunology-relevant insight contained in the global biomedical research effort, including all public high-throughput datasets, we performed immunological-pathway-focused Bayesian integration of a comprehensive, heterogeneous compendium comprising 38,088 genome-scale experiments. The distillation of this knowledge into immunological networks of functional relationships between molecular entities (ImmuNet), and tools to mine this resource, are accessible to the public at http://immunet.princeton.edu. The predictive capacity of ImmuNet, established by rigorous statistical validation, is easily accessed by experimentalists to generate data-driven hypotheses. We demonstrate the power of this approach through the identification of unique host-virus interaction responses, and we show how ImmuNet complements genetic studies by predicting disease-associated genes. ImmuNet should be widely beneficial for investigating the mechanisms of the human immune system and immunological diseases.


Assuntos
Biologia Computacional/métodos , Doenças do Sistema Imunitário/imunologia , Sistema Imunitário/imunologia , Mapeamento de Interação de Proteínas/métodos , Transdução de Sinais/imunologia , Algoritmos , Teorema de Bayes , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Sistema Imunitário/metabolismo , Doenças do Sistema Imunitário/genética , Internet , Mapas de Interação de Proteínas/genética , Mapas de Interação de Proteínas/imunologia , Reprodutibilidade dos Testes , Transdução de Sinais/genética , Máquina de Vetores de Suporte , Transcriptoma/genética , Transcriptoma/imunologia , Viroses/genética , Viroses/imunologia , Viroses/virologia
3.
Am J Physiol Endocrinol Metab ; 322(3): E260-E277, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35068187

RESUMO

Age-related declines in cardiorespiratory fitness and physical function are mitigated by regular endurance exercise in older adults. This may be due, in part, to changes in the transcriptional program of skeletal muscle following repeated bouts of exercise. However, the impact of chronic exercise training on the transcriptional response to an acute bout of endurance exercise has not been clearly determined. Here, we characterized baseline differences in muscle transcriptome and exercise-induced response in older adults who were active/endurance trained or sedentary. RNA-sequencing was performed on vastus lateralis biopsy specimens obtained before, immediately after, and 3 h following a bout of endurance exercise (40 min of cycling at 60%-70% of heart rate reserve). Using a recently developed bioinformatics approach, we found that transcript signatures related to type I myofibers, mitochondria, and endothelial cells were higher in active/endurance-trained adults and were associated with key phenotypic features including V̇o2peak, ATPmax, and muscle fiber proportion. Immune cell signatures were elevated in the sedentary group and linked to visceral and intermuscular adipose tissue mass. Following acute exercise, we observed distinct temporal transcriptional signatures that were largely similar among groups. Enrichment analysis revealed catabolic processes were uniquely enriched in the sedentary group at the 3-h postexercise timepoint. In summary, this study revealed key transcriptional signatures that distinguished active and sedentary adults, which were associated with difference in oxidative capacity and depot-specific adiposity. The acute response signatures were consistent with beneficial effects of endurance exercise to improve muscle health in older adults irrespective of exercise history and adiposity.NEW & NOTEWORTHY Muscle transcript signatures associated with oxidative capacity and immune cells underlie important phenotypic and clinical characteristics of older adults who are endurance trained or sedentary. Despite divergent phenotypes, the temporal transcriptional signatures in response to an acute bout of endurance exercise were largely similar among groups. These data provide new insight into the transcriptional programs of aging muscle and the beneficial effects of endurance exercise to promote healthy aging in older adults.


Assuntos
Resistência Física , Transcriptoma , Idoso , Células Endoteliais , Exercício Físico/fisiologia , Humanos , Músculo Esquelético/metabolismo , Resistência Física/fisiologia
4.
Nat Methods ; 16(7): 607-610, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31249421

RESUMO

A major challenge in gene expression analysis is to accurately infer relevant biological insights, such as variation in cell-type proportion or pathway activity, from global gene expression studies. We present pathway-level information extractor (PLIER) ( https://github.com/wgmao/PLIER and http://gobie.csb.pitt.edu/PLIER ), a broadly applicable solution for this problem that outperforms available cell proportion inference algorithms and can automatically identify specific pathways that regulate gene expression. Our method improves interstudy replicability and reveals biological insights when applied to trans-eQTL (expression quantitative trait loci) identification.


Assuntos
Regulação da Expressão Gênica , Armazenamento e Recuperação da Informação , Algoritmos , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
5.
Genome Res ; 28(9): 1415-1425, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30061115

RESUMO

With the emergence of zebrafish as an important model organism, a concerted effort has been made to study its transcriptome. This effort is limited, however, by gaps in zebrafish annotation, which are especially pronounced concerning transcripts dynamically expressed during zygotic genome activation (ZGA). To date, short-read sequencing has been the principal technology for zebrafish transcriptome annotation. In part because these sequence reads are too short for assembly methods to resolve the full complexity of the transcriptome, the current annotation is rudimentary. By providing direct observation of full-length transcripts, recently refined long-read sequencing platforms can dramatically improve annotation coverage and accuracy. Here, we leveraged the SMRT platform to study the transcriptome of zebrafish embryos before and after ZGA. Our analysis revealed additional novelty and complexity in the zebrafish transcriptome, identifying 2539 high-confidence novel transcripts that originated from previously unannotated loci and 1835 high-confidence new isoforms in previously annotated genes. We validated these findings using a suite of computational approaches including structural prediction, sequence homology, and functional conservation analyses, as well as by confirmatory transcript quantification with short-read sequencing data. Our analyses provided insight into new homologs and paralogs of functionally important proteins and noncoding RNAs, isoform switching occurrences, and different classes of novel splicing events. Several novel isoforms representing distinct splicing events were validated through PCR experiments, including the discovery and validation of a novel 8-kb transcript spanning multiple mir-430 elements, an important driver of early development. Our study provides a significantly improved zebrafish transcriptome annotation resource.


Assuntos
Anotação de Sequência Molecular , Transcriptoma , Peixe-Zebra/genética , Animais , Análise de Sequência de RNA/métodos , Análise de Sequência de RNA/normas , Homologia de Sequência do Ácido Nucleico
6.
Nat Methods ; 15(12): 1049-1052, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30478325

RESUMO

A key unmet challenge in interpreting omics experiments is inferring biological meaning in the context of public functional genomics data. We developed a computational framework, Your Evidence Tailored Integration (YETI; http://yeti.princeton.edu/ ), which creates specialized functional interaction maps from large public datasets relevant to an individual omics experiment. Using this tailored integration, we predicted and experimentally confirmed an unexpected divergence in viral replication after seasonal or pandemic human influenza virus infection.


Assuntos
Interpretação Estatística de Dados , Redes Reguladoras de Genes , Genômica/métodos , Influenza Humana/genética , Orthomyxoviridae/fisiologia , Proteínas Virais/genética , Replicação Viral , Algoritmos , Células Cultivadas , Conjuntos de Dados como Assunto , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Humanos , Influenza Humana/metabolismo , Influenza Humana/virologia
7.
Am J Transplant ; 20(12): 3477-3485, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32459070

RESUMO

Tacrolimus (Tac) is an effective anti-rejection agent in kidney transplantation, but its off-target effects make withdrawal desirable. Although studies indicate that Tac can be safely withdrawn in a subset of kidney transplant recipients, immune mechanisms that underlie successful vs unsuccessful Tac removal are unknown. We performed microarray analyses of peripheral blood mononuclear cells (PBMC) RNA from subjects enrolled in the Clinical Trials in Organ Transplantation-09 study in which we randomized stable kidney transplant recipients to Tac withdrawal or maintenance of standard immunosuppression beginning 6 months after transplant. Eight of 14 subjects attempted but failed withdrawal, while six developed stable graft function for ≥2 years on mycophenolate mofetil plus prednisone. Whereas failed withdrawal upregulated immune activation genes, successful Tac withdrawal was associated with a downregulatory and proapoptotic gene program enriched within T cells. Functional analyses suggested stronger donor-reactive immunity in subjects who failed withdrawal without evidence of regulatory T cell dysfunction. Together, our data from a small, but unique, patient cohort support the conclusion that successful Tac withdrawal is not simply due to absence of donor-reactive immunity but rather is associated with an active immunological process.


Assuntos
Imunossupressores , Transplante de Rim , Tacrolimo , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/etiologia , Humanos , Imunossupressores/administração & dosagem , Transplante de Rim/efeitos adversos , Leucócitos Mononucleares , Ácido Micofenólico/uso terapêutico , Tacrolimo/administração & dosagem , Transplantados
8.
J Virol ; 93(20)2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31375585

RESUMO

Early interactions of influenza A virus (IAV) with respiratory epithelium might determine the outcome of infection. The study of global cellular innate immune responses often masks multiple aspects of the mechanisms by which populations of cells work as organized and heterogeneous systems to defeat virus infection, and how the virus counteracts these systems. In this study, we experimentally dissected the dynamics of IAV and human epithelial respiratory cell interaction during early infection at the single-cell level. We found that the number of viruses infecting a cell (multiplicity of infection [MOI]) influences the magnitude of virus antagonism of the host innate antiviral response. Infections performed at high MOIs resulted in increased viral gene expression per cell and stronger antagonist effect than infections at low MOIs. In addition, single-cell patterns of expression of interferons (IFN) and IFN-stimulated genes (ISGs) provided important insights into the contributions of the infected and bystander cells to the innate immune responses during infection. Specifically, the expression of multiple ISGs was lower in infected than in bystander cells. In contrast with other IFNs, IFN lambda 1 (IFNL1) showed a widespread pattern of expression, suggesting a different cell-to-cell propagation mechanism more reliant on paracrine signaling. Finally, we measured the dynamics of the antiviral response in primary human epithelial cells, which highlighted the importance of early innate immune responses at inhibiting virus spread.IMPORTANCE Influenza A virus (IAV) is a respiratory pathogen of high importance to public health. Annual epidemics of seasonal IAV infections in humans are a significant public health and economic burden. IAV also causes sporadic pandemics, which can have devastating effects. The main target cells for IAV replication are epithelial cells in the respiratory epithelium. The cellular innate immune responses induced in these cells upon infection are critical for defense against the virus, and therefore, it is important to understand the complex interactions between the virus and the host cells. In this study, we investigated the innate immune response to IAV in the respiratory epithelium at the single-cell level, providing a better understanding on how a population of epithelial cells functions as a complex system to orchestrate the response to virus infection and how the virus counteracts this system.


Assuntos
Células Epiteliais/metabolismo , Células Epiteliais/virologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Influenza Humana/metabolismo , Interferons/biossíntese , Interleucinas/biossíntese , Perfilação da Expressão Gênica , Regulação Viral da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Humanos , Imunidade Inata/genética , Vírus da Influenza A/genética , Influenza Humana/genética , Influenza Humana/virologia , Interferons/genética , Interleucinas/genética , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , Análise de Célula Única , Proteínas não Estruturais Virais/genética
9.
PLoS Biol ; 14(5): e1002467, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27213272

RESUMO

Growth factors of the gp130 family promote oligodendrocyte differentiation, and viability, and myelination, but their mechanisms of action are incompletely understood. Here, we show that these effects are coordinated, in part, by the transcriptional activator Krüppel-like factor-6 (Klf6). Klf6 is rapidly induced in oligodendrocyte progenitors (OLP) by gp130 factors, and promotes differentiation. Conversely, in mice with lineage-selective Klf6 inactivation, OLP undergo maturation arrest followed by apoptosis, and CNS myelination fails. Overlapping transcriptional and chromatin occupancy analyses place Klf6 at the nexus of a novel gp130-Klf-importin axis, which promotes differentiation and viability in part via control of nuclear trafficking. Klf6 acts as a gp130-sensitive transactivator of the nuclear import factor importin-α5 (Impα5), and interfering with this mechanism interrupts step-wise differentiation. Underscoring the significance of this axis in vivo, mice with conditional inactivation of gp130 signaling display defective Klf6 and Impα5 expression, OLP maturation arrest and apoptosis, and failure of CNS myelination.


Assuntos
Sistema Nervoso Central/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Diferenciação Celular , Sobrevivência Celular/genética , Cromatina/metabolismo , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fator 6 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Proteínas Proto-Oncogênicas/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , alfa Carioferinas/metabolismo
10.
J Virol ; 89(20): 10190-205, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26223639

RESUMO

UNLABELLED: Influenza viruses continue to present global threats to human health. Antigenic drift and shift, genetic reassortment, and cross-species transmission generate new strains with differences in epidemiology and clinical severity. We compared the temporal transcriptional responses of human dendritic cells (DC) to infection with two pandemic (A/Brevig Mission/1/1918, A/California/4/2009) and two seasonal (A/New Caledonia/20/1999, A/Texas/36/1991) H1N1 influenza viruses. Strain-specific response differences included stronger activation of NF-κB following infection with A/New Caledonia/20/1999 and a unique cluster of genes expressed following infection with A/Brevig Mission/1/1918. A common antiviral program showing strain-specific timing was identified in the early DC response and found to correspond with reported transcript changes in blood during symptomatic human influenza virus infection. Comparison of the global responses to the seasonal and pandemic strains showed that a dramatic divergence occurred after 4 h, with only the seasonal strains inducing widespread mRNA loss. IMPORTANCE: Continuously evolving influenza viruses present a global threat to human health; however, these host responses display strain-dependent differences that are incompletely understood. Thus, we conducted a detailed comparative study assessing the immune responses of human DC to infection with two pandemic and two seasonal H1N1 influenza strains. We identified in the immune response to viral infection both common and strain-specific features. Among the stain-specific elements were a time shift of the interferon-stimulated gene response, selective induction of NF-κB signaling by one of the seasonal strains, and massive RNA degradation as early as 4 h postinfection by the seasonal, but not the pandemic, viruses. These findings illuminate new aspects of the distinct differences in the immune responses to pandemic and seasonal influenza viruses.


Assuntos
Células Dendríticas/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Pandêmica, 1918-1919/história , Influenza Humana/epidemiologia , Pandemias , Vírus Reordenados/imunologia , Variação Antigênica , Células Dendríticas/virologia , Europa (Continente)/epidemiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , História do Século XX , História do Século XXI , Interações Hospedeiro-Patógeno , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/genética , Influenza Humana/história , Influenza Humana/imunologia , Interferons/genética , Interferons/imunologia , Epidemiologia Molecular , NF-kappa B/genética , NF-kappa B/imunologia , Vírus Reordenados/genética , Recombinação Genética , Estações do Ano , Transdução de Sinais , Fatores de Tempo , Estados Unidos/epidemiologia
11.
Bioinformatics ; 31(10): 1584-91, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25583121

RESUMO

MOTIVATION: Identifying alterations in gene expression associated with different clinical states is important for the study of human biology. However, clinical samples used in gene expression studies are often derived from heterogeneous mixtures with variable cell-type composition, complicating statistical analysis. Considerable effort has been devoted to modeling sample heterogeneity, and presently, there are many methods that can estimate cell proportions or pure cell-type expression from mixture data. However, there is no method that comprehensively addresses mixture analysis in the context of differential expression without relying on additional proportion information, which can be inaccurate and is frequently unavailable. RESULTS: In this study, we consider a clinically relevant situation where neither accurate proportion estimates nor pure cell expression is of direct interest, but where we are rather interested in detecting and interpreting relevant differential expression in mixture samples. We develop a method, Cell-type COmputational Differential Estimation (CellCODE), that addresses the specific statistical question directly, without requiring a physical model for mixture components. Our approach is based on latent variable analysis and is computationally transparent; it requires no additional experimental data, yet outperforms existing methods that use independent proportion measurements. CellCODE has few parameters that are robust and easy to interpret. The method can be used to track changes in proportion, improve power to detect differential expression and assign the differentially expressed genes to the correct cell type.


Assuntos
Linhagem da Célula/genética , Biologia Computacional/métodos , Interpretação Estatística de Dados , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Software , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linfócitos B/virologia , Humanos , Vacinas contra Influenza/administração & dosagem , Modelos Estatísticos , Neutrófilos/citologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Análise de Sequência de RNA/métodos , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Linfócitos T/virologia , Fatores de Tempo
12.
Brain ; 138(Pt 6): 1548-67, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25805644

RESUMO

In inflammatory central nervous system conditions such as multiple sclerosis, breakdown of the blood-brain barrier is a key event in lesion pathogenesis, predisposing to oedema, excitotoxicity, and ingress of plasma proteins and inflammatory cells. Recently, we showed that reactive astrocytes drive blood-brain barrier opening, via production of vascular endothelial growth factor A (VEGFA). Here, we now identify thymidine phosphorylase (TYMP; previously known as endothelial cell growth factor 1, ECGF1) as a second key astrocyte-derived permeability factor, which interacts with VEGFA to induce blood-brain barrier disruption. The two are co-induced NFκB1-dependently in human astrocytes by the cytokine interleukin 1 beta (IL1B), and inactivation of Vegfa in vivo potentiates TYMP induction. In human central nervous system microvascular endothelial cells, VEGFA and the TYMP product 2-deoxy-d-ribose cooperatively repress tight junction proteins, driving permeability. Notably, this response represents part of a wider pattern of endothelial plasticity: 2-deoxy-d-ribose and VEGFA produce transcriptional programs encompassing angiogenic and permeability genes, and together regulate a third unique cohort. Functionally, each promotes proliferation and viability, and they cooperatively drive motility and angiogenesis. Importantly, introduction of either into mouse cortex promotes blood-brain barrier breakdown, and together they induce severe barrier disruption. In the multiple sclerosis model experimental autoimmune encephalitis, TYMP and VEGFA co-localize to reactive astrocytes, and correlate with blood-brain barrier permeability. Critically, blockade of either reduces neurologic deficit, blood-brain barrier disruption and pathology, and inhibiting both in combination enhances tissue preservation. Suggesting importance in human disease, TYMP and VEGFA both localize to reactive astrocytes in multiple sclerosis lesion samples. Collectively, these data identify TYMP as an astrocyte-derived permeability factor, and suggest TYMP and VEGFA together promote blood-brain barrier breakdown.


Assuntos
Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Timidina Fosforilase/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Barreira Hematoencefálica/fisiopatologia , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Desoxirribose/fisiologia , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/fisiopatologia , Endotélio Vascular/metabolismo , Humanos , Interleucina-1beta/farmacologia , Camundongos , Camundongos Transgênicos , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Timidina Fosforilase/antagonistas & inibidores , Timidina Fosforilase/farmacologia , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/farmacologia
13.
J Appl Physiol (1985) ; 136(2): 244-261, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095016

RESUMO

We investigated fast and slow muscle fiber transcriptome exercise dynamics among three groups of men: lifelong exercisers (LLE, n = 8, 74 ± 1 yr), old healthy nonexercisers (OH, n = 9, 75 ± 1 yr), and young exercisers (YE, n = 8, 25 ± 1 yr). On average, LLE had exercised ∼4 day·wk-1 for ∼8 h·wk-1 over 53 ± 2 years. Muscle biopsies were obtained pre- and 4 h postresistance exercise (3 × 10 knee extensions at 70% 1-RM). Fast and slow fiber size and function were assessed preexercise with fast and slow RNA-seq profiles examined pre- and postexercise. LLE fast fiber size was similar to OH, which was ∼30% smaller than YE (P < 0.05) with contractile function variables among groups, resulting in lower power in LLE (P < 0.05). LLE slow fibers were ∼30% larger and more powerful compared with YE and OH (P < 0.05). At the transcriptome level, fast fibers were more responsive to resistance exercise compared with slow fibers among all three cohorts (P < 0.05). Exercise induced a comprehensive biological response in fast fibers (P < 0.05) including transcription, signaling, skeletal muscle cell differentiation, and metabolism with vast differences among the groups. Fast fibers from YE exhibited a growth and metabolic signature, with LLE being primarily metabolic, and OH showing a strong stress-related response. In slow fibers, only LLE exhibited a biological response to exercise (P < 0.05), which was related to ketone and lipid metabolism. The divergent exercise transcriptome signatures provide novel insight into the molecular regulation in fast and slow fibers with age and exercise and suggest that the ∼5% weekly exercise time commitment of the lifelong exercisers provided a powerful investment for fast and slow muscle fiber metabolic health at the molecular level.NEW & NOTEWORTHY This study provides the first insights into fast and slow muscle fiber transcriptome dynamics with lifelong endurance exercise. The fast fibers were more responsive to exercise with divergent transcriptome signatures among young exercisers (growth and metabolic), lifelong exercisers (metabolic), and old healthy nonexercisers (stress). Only lifelong exercisers had a biological response in slow fibers (metabolic). These data provide novel insights into fast and slow muscle fiber health at the molecular level with age and exercise.


Assuntos
Fibras Musculares de Contração Rápida , Fibras Musculares de Contração Lenta , Masculino , Humanos , Fibras Musculares de Contração Rápida/fisiologia , Fibras Musculares de Contração Lenta/fisiologia , Transcriptoma , Exercício Físico/fisiologia , Fibras Musculares Esqueléticas , Músculo Esquelético/fisiologia
14.
Cell Genom ; 4(6): 100421, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38697122

RESUMO

Regular exercise has many physical and brain health benefits, yet the molecular mechanisms mediating exercise effects across tissues remain poorly understood. Here we analyzed 400 high-quality DNA methylation, ATAC-seq, and RNA-seq datasets from eight tissues from control and endurance exercise-trained (EET) rats. Integration of baseline datasets mapped the gene location dependence of epigenetic control features and identified differing regulatory landscapes in each tissue. The transcriptional responses to 8 weeks of EET showed little overlap across tissues and predominantly comprised tissue-type enriched genes. We identified sex differences in the transcriptomic and epigenomic changes induced by EET. However, the sex-biased gene responses were linked to shared signaling pathways. We found that many G protein-coupled receptor-encoding genes are regulated by EET, suggesting a role for these receptors in mediating the molecular adaptations to training across tissues. Our findings provide new insights into the mechanisms underlying EET-induced health benefits across organs.


Assuntos
Condicionamento Físico Animal , Transcriptoma , Animais , Condicionamento Físico Animal/fisiologia , Masculino , Ratos , Feminino , Metilação de DNA , Epigênese Genética , Epigenômica , Adaptação Fisiológica/genética , Especificidade de Órgãos , Ratos Sprague-Dawley
15.
BMC Bioinformatics ; 14 Suppl 6: S1, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23734902

RESUMO

BACKGROUND: H1N1 influenza viruses were responsible for the 1918 pandemic that caused millions of deaths worldwide and the 2009 pandemic that caused approximately twenty thousand deaths. The cellular response to such virus infections involves extensive genetic reprogramming resulting in an antiviral state that is critical to infection control. Identifying the underlying transcriptional network driving these changes, and how this program is altered by virally-encoded immune antagonists, is a fundamental challenge in systems immunology. RESULTS: Genome-wide gene expression patterns were measured in human monocyte-derived dendritic cells (DCs) infected in vitro with seasonal H1N1 influenza A/New Caledonia/20/1999. To provide a mechanistic explanation for the timing of gene expression changes over the first 12 hours post-infection, we developed a statistically rigorous enrichment approach integrating genome-wide expression kinetics and time-dependent promoter analysis. Our approach, TIme-Dependent Activity Linker (TIDAL), generates a regulatory network that connects transcription factors associated with each temporal phase of the response into a coherent linked cascade. TIDAL infers 12 transcription factors and 32 regulatory connections that drive the antiviral response to influenza. To demonstrate the generality of this approach, TIDAL was also used to generate a network for the DC response to measles infection. The software implementation of TIDAL is freely available at http://tsb.mssm.edu/primeportal/?q=tidal_prog. CONCLUSIONS: We apply TIDAL to reconstruct the transcriptional programs activated in monocyte-derived human dendritic cells in response to influenza and measles infections. The application of this time-centric network reconstruction method in each case produces a single transcriptional cascade that recapitulates the known biology of the response with high precision and recall, in addition to identifying potentially novel antiviral factors. The ability to reconstruct antiviral networks with TIDAL enables comparative analysis of antiviral responses, such as the differences between pandemic and seasonal influenza infections.


Assuntos
Biologia Computacional/métodos , Células Dendríticas/metabolismo , Regulação Viral da Expressão Gênica , Redes Reguladoras de Genes , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/genética , Influenza Humana/imunologia , Software , Células Dendríticas/imunologia , Células Dendríticas/microbiologia , Humanos , Influenza Humana/fisiopatologia , Influenza Humana/virologia , Fatores de Transcrição/metabolismo
16.
bioRxiv ; 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37961197

RESUMO

To facilitate single cell multi-omics analysis and improve reproducibility, we present SPEEDI (Single-cell Pipeline for End to End Data Integration), a fully automated end-to-end framework for batch inference, data integration, and cell type labeling. SPEEDI introduces data-driven batch inference and transforms the often heterogeneous data matrices obtained from different samples into a uniformly annotated and integrated dataset. Without requiring user input, it automatically selects parameters and executes pre-processing, sample integration, and cell type mapping. It can also perform downstream analyses of differential signals between treatment conditions and gene functional modules. SPEEDI's data-driven batch inference method works with widely used integration and cell-typing tools. By developing data-driven batch inference, providing full end-to-end automation, and eliminating parameter selection, SPEEDI improves reproducibility and lowers the barrier to obtaining biological insight from these valuable single-cell datasets. The SPEEDI interactive web application can be accessed at https://speedi.princeton.edu/.

17.
bioRxiv ; 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37808658

RESUMO

Endurance exercise is an important health modifier. We studied cell-type specific adaptations of human skeletal muscle to acute endurance exercise using single-nucleus (sn) multiome sequencing in human vastus lateralis samples collected before and 3.5 hours after 40 min exercise at 70% VO2max in four subjects, as well as in matched time of day samples from two supine resting circadian controls. High quality same-cell RNA-seq and ATAC-seq data were obtained from 37,154 nuclei comprising 14 cell types. Among muscle fiber types, both shared and fiber-type specific regulatory programs were identified. Single-cell circuit analysis identified distinct adaptations in fast, slow and intermediate fibers as well as LUM-expressing FAP cells, involving a total of 328 transcription factors (TFs) acting at altered accessibility sites regulating 2,025 genes. These data and circuit mapping provide single-cell insight into the processes underlying tissue and metabolic remodeling responses to exercise.

18.
bioRxiv ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36711841

RESUMO

Transcription factors (TFs) play a key role in regulating gene expression and responses to stimuli. We conducted an integrated analysis of chromatin accessibility, DNA methylation, and RNA expression across eight rat tissues following endurance exercise training (EET) to map epigenomic changes to transcriptional changes and determine key TFs involved. We uncovered tissue-specific changes and TF motif enrichment across all omic layers, differentially accessible regions (DARs), differentially methylated regions (DMRs), and differentially expressed genes (DEGs). We discovered distinct routes of EET-induced regulation through either epigenomic alterations providing better access for TFs to affect target genes, or via changes in TF expression or activity enabling target gene response. We identified TF motifs enriched among correlated epigenomic and transcriptomic alterations, DEGs correlated with exercise-related phenotypic changes, and EET-induced activity changes of TFs enriched for DEGs among their gene targets. This analysis elucidates the unique transcriptional regulatory mechanisms mediating diverse organ effects of EET.

19.
Cell Rep Methods ; 3(2): 100395, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36936082

RESUMO

Assays detecting blood transcriptome changes are studied for infectious disease diagnosis. Blood-based RNA alternative splicing (AS) events, which have not been well characterized in pathogen infection, have potential normalization and assay platform stability advantages over gene expression for diagnosis. Here, we present a computational framework for developing AS diagnostic biomarkers. Leveraging a large prospective cohort of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and whole-blood RNA sequencing (RNA-seq) data, we identify a major functional AS program switch upon viral infection. Using an independent cohort, we demonstrate the improved accuracy of AS biomarkers for SARS-CoV-2 diagnosis compared with six reported transcriptome signatures. We then optimize a subset of AS-based biomarkers to develop microfluidic PCR diagnostic assays. This assay achieves nearly perfect test accuracy (61/62 = 98.4%) using a naive principal component classifier, significantly more accurate than a gene expression PCR assay in the same cohort. Therefore, our RNA splicing computational framework enables a promising avenue for host-response diagnosis of infection.


Assuntos
COVID-19 , Doenças Transmissíveis , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Processamento Alternativo/genética , Teste para COVID-19 , RNA , Estudos Prospectivos , Biomarcadores/análise
20.
Nat Comput Sci ; 3(7): 644-657, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37974651

RESUMO

Resolving chromatin-remodeling-linked gene expression changes at cell-type resolution is important for understanding disease states. Here we describe MAGICAL (Multiome Accessibility Gene Integration Calling and Looping), a hierarchical Bayesian approach that leverages paired single-cell RNA sequencing and single-cell transposase-accessible chromatin sequencing from different conditions to map disease-associated transcription factors, chromatin sites, and genes as regulatory circuits. By simultaneously modeling signal variation across cells and conditions in both omics data types, MAGICAL achieved high accuracy on circuit inference. We applied MAGICAL to study Staphylococcus aureus sepsis from peripheral blood mononuclear single-cell data that we generated from subjects with bloodstream infection and uninfected controls. MAGICAL identified sepsis-associated regulatory circuits predominantly in CD14 monocytes, known to be activated by bacterial sepsis. We addressed the challenging problem of distinguishing host regulatory circuit responses to methicillin-resistant and methicillin-susceptible S. aureus infections. Although differential expression analysis failed to show predictive value, MAGICAL identified epigenetic circuit biomarkers that distinguished methicillin-resistant from methicillin-susceptible S. aureus infections.

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