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1.
Mol Cell ; 81(5): 983-997.e7, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33539786

RESUMO

Gene transcription occurs via a cycle of linked events, including initiation, promoter-proximal pausing, and elongation of RNA polymerase II (Pol II). A key question is how transcriptional enhancers influence these events to control gene expression. Here, we present an approach that evaluates the level and change in promoter-proximal transcription (initiation and pausing) in the context of differential gene expression, genome-wide. This combinatorial approach shows that in primary cells, control of gene expression during differentiation is achieved predominantly via changes in transcription initiation rather than via release of Pol II pausing. Using genetically engineered mouse models, deleted for functionally validated enhancers of the α- and ß-globin loci, we confirm that these elements regulate Pol II recruitment and/or initiation to modulate gene expression. Together, our data show that gene expression during differentiation is regulated predominantly at the level of initiation and that enhancers are key effectors of this process.


Assuntos
Elementos Facilitadores Genéticos , Regiões Promotoras Genéticas , RNA Polimerase II/genética , Iniciação da Transcrição Genética , alfa-Globinas/genética , Globinas beta/genética , Animais , Diferenciação Celular , Éxons , Feto , Regulação da Expressão Gênica , Biblioteca Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Íntrons , Células K562 , Fígado/citologia , Fígado/metabolismo , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Polimerase II/metabolismo , Transdução de Sinais , alfa-Globinas/deficiência , Globinas beta/deficiência
2.
Ann Intern Med ; 177(2): 155-164, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38252942

RESUMO

BACKGROUND: Sickle cell disease (SCD) and its complications contribute to high rates of morbidity and early mortality and high cost in the United States and African heritage community. OBJECTIVE: To evaluate the cost-effectiveness of gene therapy for SCD and its value-based prices (VBPs). DESIGN: Comparative modeling analysis across 2 independently developed simulation models (University of Washington Model for Economic Analysis of Sickle Cell Cure [UW-MEASURE] and Fred Hutchinson Institute Sickle Cell Disease Outcomes Research and Economics Model [FH-HISCORE]) using the same databases. DATA SOURCES: Centers for Medicare & Medicaid Services claims data, 2008 to 2016; published literature. TARGET POPULATION: Persons eligible for gene therapy. TIME HORIZON: Lifetime. PERSPECTIVE: U.S. health care sector and societal. INTERVENTION: Gene therapy versus common care. OUTCOME MEASURES: Incremental cost-effectiveness ratios (ICERs), equity-informed VBPs, and price acceptability curves. RESULTS OF BASE-CASE ANALYSIS: At an assumed $2 million price for gene therapy, UW-MEASURE and FH-HISCORE estimated ICERs of $193 000 per QALY and $427 000 per QALY, respectively, under the health care sector perspective. Corresponding estimates from the societal perspective were $126 000 per QALY and $281 000 per QALY. The difference in results between models stemmed primarily from considering a slightly different target population and incorporating the quality-of-life (QOL) effects of splenic sequestration, priapism, and acute chest syndrome in the UW model. From a societal perspective, acceptable (>90% confidence) VBPs ranged from $1 million to $2.5 million depending on the use of alternative effective metrics or equity-informed threshold values. RESULTS OF SENSITIVITY ANALYSIS: Results were sensitive to the costs of myeloablative conditioning before gene therapy, effect on caregiver QOL, and effect of gene therapy on long-term survival. LIMITATION: The short-term effects of gene therapy on vaso-occlusive events were extrapolated from 1 study. CONCLUSION: Gene therapy for SCD below a $2 million price tag is likely to be cost-effective when applying a societal perspective at an equity-informed threshold for cost-effectiveness analysis. PRIMARY FUNDING SOURCE: National Heart, Lung, and Blood Institute.


Assuntos
Anemia Falciforme , Análise de Custo-Efetividade , Idoso , Masculino , Humanos , Estados Unidos , Qualidade de Vida , Análise Custo-Benefício , Medicare , Anemia Falciforme/genética , Anemia Falciforme/terapia , Anos de Vida Ajustados por Qualidade de Vida
3.
BMC Bioinformatics ; 23(1): 156, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501696

RESUMO

BACKGROUND: Quantification of gene expression from RNA-seq data is a prerequisite for transcriptome analysis such as differential gene expression analysis and gene co-expression network construction. Individual RNA-seq experiments are larger and combining multiple experiments from sequence repositories can result in datasets with thousands of samples. Processing hundreds to thousands of RNA-seq data can result in challenges related to data management, access to sufficient computational resources, navigation of high-performance computing (HPC) systems, installation of required software dependencies, and reproducibility. Processing of larger and deeper RNA-seq experiments will become more common as sequencing technology matures. RESULTS: GEMmaker, is a nf-core compliant, Nextflow workflow, that quantifies gene expression from small to massive RNA-seq datasets. GEMmaker ensures results are highly reproducible through the use of versioned containerized software that can be executed on a single workstation, institutional compute cluster, Kubernetes platform or the cloud. GEMmaker supports popular alignment and quantification tools providing results in raw and normalized formats. GEMmaker is unique in that it can scale to process thousands of local or remote stored samples without exceeding available data storage. CONCLUSIONS: Workflows that quantify gene expression are not new, and many already address issues of portability, reusability, and scale in terms of access to CPUs. GEMmaker provides these benefits and adds the ability to scale despite low data storage infrastructure. This allows users to process hundreds to thousands of RNA-seq samples even when data storage resources are limited. GEMmaker is freely available and fully documented with step-by-step setup and execution instructions.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Software , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA-Seq , Reprodutibilidade dos Testes , Análise de Sequência de RNA/métodos
4.
BMC Cancer ; 22(1): 612, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35659616

RESUMO

BACKGROUND: Thyroid cancer (THCA) is the most common endocrine malignancy and incidence is increasing. There is an urgent need to better understand the molecular differences between THCA tumors at different pathologic stages so appropriate diagnostic, prognostic, and treatment strategies can be applied. Transcriptome State Perturbation Generator (TSPG) is a tool created to identify the changes in gene expression necessary to transform the transcriptional state of a source sample to mimic that of a target. METHODS: We used TSPG to perturb the bulk RNA expression data from various THCA tumor samples at progressive stages towards the transcriptional pattern of normal thyroid tissue. The perturbations produced were analyzed to determine if there are consistently up- or down-regulated genes or functions in certain stages of tumors. RESULTS: Some genes of particular interest were investigated further in previous research. SLC6A15 was found to be down-regulated in all stage 1-3 samples. This gene has previously been identified as a tumor suppressor. The up-regulation of PLA2G12B in all samples was notable because the protein encoded by this gene belongs to the PLA2 superfamily, which is involved in metabolism, a major function of the thyroid gland. REN was up-regulated in all stage 3 and 4 samples. The enzyme renin encoded by this gene, has a role in the renin-angiotensin system; this system regulates angiogenesis and may have a role in cancer development and progression. This is supported by the consistent up-regulation of REN only in later stage tumor samples. Functional enrichment analysis showed that olfactory receptor activities and similar terms were enriched for the up-regulated genes which supports previous research concluding that abundance and stimulation of olfactory receptors is linked to cancer. CONCLUSIONS: TSPG can be a useful tool in exploring large gene expression datasets and extracting the meaningful differences between distinct classes of data. We identified genes that were characteristically perturbed in certain sample types, including only late-stage THCA tumors. Additionally, we provided evidence for potential transcriptional signatures of each stage of thyroid cancer. These are potentially relevant targets for future investigation into THCA tumorigenesis.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros , Aprendizado Profundo , Neoplasias da Glândula Tireoide , Sistemas de Transporte de Aminoácidos Neutros/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas do Tecido Nervoso/genética , Prognóstico , Neoplasias da Glândula Tireoide/patologia , Transcriptoma
5.
Value Health ; 25(2): 276-287, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35094801

RESUMO

OBJECTIVES: Sickle cell disease (SCD) is a complex, chronic condition that impairs health-related quality of life of affected individuals and their caregivers. As curative therapies emerge, comprehensive cost-effectiveness models will inform their value. These models will require descriptions of health states and their corresponding utility values that accurately reflect health-related quality of life over the disease trajectory. The objectives of this systematic review were to develop a catalog of health state utility (HSU) values for SCD, identify research gaps, and provide future directions for preference elicitation. METHODS: Records were identified through searches of PubMed and Embase, Tufts Medical Center Cost-Effectiveness Analysis Registry, reference lists of relevant articles, and consultation with SCD experts (2008-2020). We removed duplicate records and excluded ineligible studies. For included studies, we summarized the study characteristics, methods used for eliciting HSUs, and HSU values. RESULTS: Five studies empirically elicited utilities using indirect methods (EQ-5D) (n = 3) and Short Form-6 Dimension (n = 2); these represent health states associated with general SCD (n = 1), SCD complications (n = 2), and SCD treatments (n = 3). Additionally, we extracted HSUs from 7 quality-adjusted life-years-based outcome research studies. The HSU among patients with general SCD without specifying complications ranged from 0.64 to 0.887. Only 36% of the HSUs used in the quality-adjusted life-year-based outcomes research studies were derived from individuals with SCD. No study estimated HSUs in caregivers. CONCLUSIONS: There is a dearth of literature of HSUs for use in SCD models. Future empirical studies should elicit a comprehensive set of HSUs from individuals with SCD and their caregivers.


Assuntos
Anemia Falciforme/economia , Anemia Falciforme/terapia , Qualidade de Vida , Adulto , Anemia Falciforme/epidemiologia , Antidrepanocíticos/uso terapêutico , Transfusão de Sangue/métodos , Criança , Comorbidade , Análise Custo-Benefício , Feminino , Indicadores Básicos de Saúde , Humanos , Hidroxiureia/uso terapêutico , Masculino , Avaliação de Resultados em Cuidados de Saúde , Dor/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Inquéritos e Questionários
6.
Qual Life Res ; 31(9): 2729-2738, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35715626

RESUMO

PURPOSE: There is a paucity of empirically estimated health state utility (HSU) values to estimate health-related quality of life among individuals with sickle cell disease (SCD). This study aims to map the Pediatric Quality of Life Inventory generic core scales (PedsQL GCS) to HSUs for children and adolescents with SCD in the United States, using published algorithms, and to assess the construct validity of these HSUs against SCD-specific PedsQL scores. METHODS: We used the published mapping algorithms identified in four published articles, in which the PedsQL GCS was mapped to either the EuroQol-5 Dimension 3-Level, Youth Version or the Child Health Utility 9-Dimension to obtain HSUs. We employed the algorithms to calculate HSUs for a sample of children and adolescents from the Sickle Cell Clinical Research and Intervention Program. To assess the construct validity of the mapped HSUs in SCD patients, we computed Spearman's correlation coefficient comparing the HSUs with the PedsQL SCD total score and separately with each PedsQL SCD dimension-specific score. RESULTS: The mean mapped HSU across published algorithms was 0.792 (95% CI: 0.782-0.801). It was significantly higher among children aged 5-12 years than children aged 13-17 years. The Spearman's correlation coefficient for HSUs versus PedsQL SCD total scores was 0.64 (95% CI: 0.57-0.71). Correlations ranged from 0.40 (95% CI: 0.32-0.48) to 0.60 (95% CI: 0.54-0.66) for HSUs versus PedsQL SCD dimension-specific scores. CONCLUSIONS: The existing mapping algorithms show acceptable construct validity in children and adolescents with SCD. Additional algorithms are needed for adults and for specific SCD comorbidities.


Assuntos
Anemia Falciforme , Qualidade de Vida , Adolescente , Algoritmos , Criança , Saúde da Criança , Comorbidade , Humanos , Psicometria/métodos , Qualidade de Vida/psicologia , Reprodutibilidade dos Testes , Inquéritos e Questionários
7.
Proc Biol Sci ; 288(1961): 20211712, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34666520

RESUMO

Coral reefs are experiencing declines due to climate change and local human impacts. While at a local scale these impacts induce biodiversity loss and shifts in community structure, previous biogeographical analyses recorded consistent taxonomic structure of fish communities across global coral reefs. This suggests that regional communities represent a random subset of the global species and traits pool, whatever their species richness. Using distributional data on 3586 fish species and latest advances in species distribution models, we show marked gradients in the prevalence of size classes and diet categories across the biodiversity gradient. This divergence in trait structure is best explained by reef isolation during past unfavourable climatic conditions, with large and piscivore fishes better represented in isolated areas. These results suggest the risk of a global community re-organization if the ongoing climate-induced reef fragmentation is not halted.


Assuntos
Antozoários , Recifes de Corais , Animais , Biodiversidade , Mudança Climática , Peixes , Prevalência
8.
Phys Rev Lett ; 124(9): 092502, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202869

RESUMO

We probe the N=82 nuclear shell closure by mass measurements of neutron-rich cadmium isotopes with the ISOLTRAP spectrometer at ISOLDE-CERN. The new mass of ^{132}Cd offers the first value of the N=82, two-neutron shell gap below Z=50 and confirms the phenomenon of mutually enhanced magicity at ^{132}Sn. Using the recently implemented phase-imaging ion-cyclotron-resonance method, the ordering of the low-lying isomers in ^{129}Cd and their energies are determined. The new experimental findings are used to test large-scale shell-model, mean-field, and beyond-mean-field calculations, as well as the ab initio valence-space in-medium similarity renormalization group.

9.
MMWR Morb Mortal Wkly Rep ; 69(36): 1269-1272, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32915167

RESUMO

Alpha-thalassemia comprises a group of inherited disorders in which alpha-hemoglobin chain production is reduced. Depending on the genotype, alpha-thalassemia results in moderate to profound anemia, hemolysis, growth delays, splenomegaly, and increased risk for thromboembolic events; certain patients might require chronic transfusions. Although alpha-thalassemia is not a core condition of the United States Recommended Uniform Screening Panel* for state newborn screening programs, methodologies used by some newborn screening programs to detect sickle cell disease, which is a core panel condition, also detect a quantitative marker of alpha-thalassemia, hemoglobin (Hb) Bart's, an abnormal type of hemoglobin. The percentage of Hb Bart's detected correlates with alpha-thalassemia severity. The Association of Public Health Laboratories' Hemoglobinopathy Workgroup conducted a survey of state newborn screening programs' alpha-thalassemia screening methodologies and reporting and follow-up practices. Survey findings indicated that 41 of 44 responding programs (93%) report some form of alpha-thalassemia results and 57% used a two-method screening protocol. However, the percentage of Hb Bart's used for thalassemia classification, the types of alpha-thalassemia reported, and the recipients of this information varied widely. These survey findings highlight the opportunity for newborn screening programs to revisit their policies as they reevaluate their practices in light of the recently released guideline from the Clinical and Laboratory Standards Institute (CLSI) on Newborn Screening for Hemoglobinopathies (1). Although deferring to local programs for policies, the report used a cutoff of 25% Hb Bart's in its decision tree, a value many programs do not use. Standardization of screening and reporting might lead to more timely diagnoses and health care services and improved outcomes for persons with a clinically significant alpha-thalassemia.


Assuntos
Triagem Neonatal/métodos , Talassemia alfa/diagnóstico , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Recém-Nascido , Masculino , Estados Unidos/epidemiologia , Talassemia alfa/epidemiologia
10.
Eur J Vasc Endovasc Surg ; 60(1): 49-55, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32331994

RESUMO

OBJECTIVE: The new 2019 guideline of the European Society for Vascular Surgery (ESVS) recommends consideration for elective iliac artery aneurysm (eIAA) repair when the iliac diameter exceeds 3.5 cm, as opposed to 3.0 cm previously. The current study assessed diameters at time of eIAA repair and ruptured IAA (rIAA) repair and compared clinical outcomes after open surgical repair (OSR) and endovascular aneurysm repair (EVAR). METHODS: This retrospective observational study used the nationwide Dutch Surgical Aneurysm Audit (DSAA) registry that includes all patients who undergo aorto-iliac aneurysm repair in the Netherlands. All patients who underwent primary IAA repair between 1 January 2014 and 1 January 2018 were included. Diameters at time of eIAA and rIAA repair were compared in a descriptive fashion. The anatomical location of the IAA was not registered in the registry. Patient characteristics and outcomes of OSR and EVAR were compared with appropriate statistical tests. RESULTS: The DSAA registry comprised 974 patients who underwent IAA repair. A total of 851 patients were included after exclusion of patients undergoing revision surgery and patients with missing essential variables. eIAA repair was carried out in 713 patients, rIAA repair in 102, and symptomatic IAA repair in 36. OSR was performed in 205, EVAR in 618, and hybrid repairs and conversions in 28. The median maximum IAA diameter at the time of eIAA and rIAA repair was 43 (IQR 38-50) mm and 68 (IQR 58-85) mm, respectively. Mortality was 1.3% (95% CI 0.7-2.4) after eIAA repair and 25.5% (95% CI 18.0-34.7) after rIAA repair. Mortality was not significantly different between the OSR and EVAR subgroups. Elective OSR was associated with significantly more complications than EVAR (intra-operative: 9.8% vs. 3.6%, post-operative: 34.0% vs. 13.8%, respectively). CONCLUSION: In the Netherlands, most eIAA repairs are performed at diameters larger than recommended by the ESVS guideline. These findings appear to support the recent increase in the threshold diameter for eIAA repair.


Assuntos
Aneurisma Ilíaco/cirurgia , Idoso , Idoso de 80 Anos ou mais , Procedimentos Endovasculares/métodos , Procedimentos Endovasculares/mortalidade , Procedimentos Endovasculares/estatística & dados numéricos , Feminino , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Aneurisma Ilíaco/epidemiologia , Aneurisma Ilíaco/mortalidade , Aneurisma Ilíaco/patologia , Artéria Ilíaca/patologia , Artéria Ilíaca/cirurgia , Masculino , Países Baixos/epidemiologia , Sistema de Registros , Estudos Retrospectivos , Fatores Sexuais , Resultado do Tratamento
11.
Nature ; 515(7527): 365-70, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25409825

RESUMO

The basic body plan and major physiological axes have been highly conserved during mammalian evolution, yet only a small fraction of the human genome sequence appears to be subject to evolutionary constraint. To quantify cis- versus trans-acting contributions to mammalian regulatory evolution, we performed genomic DNase I footprinting of the mouse genome across 25 cell and tissue types, collectively defining ∼8.6 million transcription factor (TF) occupancy sites at nucleotide resolution. Here we show that mouse TF footprints conjointly encode a regulatory lexicon that is ∼95% similar with that derived from human TF footprints. However, only ∼20% of mouse TF footprints have human orthologues. Despite substantial turnover of the cis-regulatory landscape, nearly half of all pairwise regulatory interactions connecting mouse TF genes have been maintained in orthologous human cell types through evolutionary innovation of TF recognition sequences. Furthermore, the higher-level organization of mouse TF-to-TF connections into cellular network architectures is nearly identical with human. Our results indicate that evolutionary selection on mammalian gene regulation is targeted chiefly at the level of trans-regulatory circuitry, enabling and potentiating cis-regulatory plasticity.


Assuntos
Sequência Conservada/genética , Evolução Molecular , Mamíferos/genética , Sequências Reguladoras de Ácido Nucleico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Pegada de DNA , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Humanos , Camundongos
12.
Nature ; 515(7527): 355-64, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25409824

RESUMO

The laboratory mouse shares the majority of its protein-coding genes with humans, making it the premier model organism in biomedical research, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases.


Assuntos
Genoma/genética , Genômica , Camundongos/genética , Anotação de Sequência Molecular , Animais , Linhagem da Célula/genética , Cromatina/genética , Cromatina/metabolismo , Sequência Conservada/genética , Replicação do DNA/genética , Desoxirribonuclease I/metabolismo , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Estudo de Associação Genômica Ampla , Humanos , RNA/genética , Sequências Reguladoras de Ácido Nucleico/genética , Especificidade da Espécie , Fatores de Transcrição/metabolismo , Transcriptoma/genética
13.
Clin Lab ; 66(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32538038

RESUMO

BACKGROUND: Calprotectin is a well-established marker for intestinal inflammation, mainly in inflammatory bowel disease, and represents one of the most studied biomarkers in stool samples. METHODS: Apart from its important diagnostic role in inflammatory bowel disease, there are few studies showing that calprotectin can also be used as a diagnostic tool in patients suffering from hepatic encephalopathy (HE) and spontaneous bacterial peritonitis (SBP) in cirrhosis. RESULTS: Since calprotectin concentration in the human stool or in ascites is elevated at an early stage of inflammation, it might serve as an early screening tool for patients suffering from cirrhosis who are at risk to develop these conditions. As detection and monitoring of HE and SBP may be unclear and resource-intensive, identification of valid new markers of disease activity is necessary. In this review, we summarize the current knowledge of calprotectin as a diagnostic biomarker in cirrhosis, indicating that it is a highly promising diagnostic surrogate marker to screen for the presence of HE and SBP. CONCLUSIONS: To screen cirrhotic patients for SBP, calprotectin should be assessed in ascitic fluid while it should be measured in feces when screening for HE. However, the value of calprotectin in managing individual patients must be considered in the specific clinical context.


Assuntos
Líquido Ascítico , Fezes , Encefalopatia Hepática , Complexo Antígeno L1 Leucocitário/análise , Cirrose Hepática , Peritonite , Biomarcadores/análise , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/imunologia , Humanos , Testes Imunológicos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/imunologia , Peritonite/diagnóstico , Peritonite/etiologia , Peritonite/imunologia
14.
Nature ; 489(7414): 83-90, 2012 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-22955618

RESUMO

Regulatory factor binding to genomic DNA protects the underlying sequence from cleavage by DNase I, leaving nucleotide-resolution footprints. Using genomic DNase I footprinting across 41 diverse cell and tissue types, we detected 45 million transcription factor occupancy events within regulatory regions, representing differential binding to 8.4 million distinct short sequence elements. Here we show that this small genomic sequence compartment, roughly twice the size of the exome, encodes an expansive repertoire of conserved recognition sequences for DNA-binding proteins that nearly doubles the size of the human cis-regulatory lexicon. We find that genetic variants affecting allelic chromatin states are concentrated in footprints, and that these elements are preferentially sheltered from DNA methylation. High-resolution DNase I cleavage patterns mirror nucleotide-level evolutionary conservation and track the crystallographic topography of protein-DNA interfaces, indicating that transcription factor structure has been evolutionarily imprinted on the human genome sequence. We identify a stereotyped 50-base-pair footprint that precisely defines the site of transcript origination within thousands of human promoters. Finally, we describe a large collection of novel regulatory factor recognition motifs that are highly conserved in both sequence and function, and exhibit cell-selective occupancy patterns that closely parallel major regulators of development, differentiation and pluripotency.


Assuntos
Pegada de DNA , DNA/genética , Enciclopédias como Assunto , Genoma Humano/genética , Anotação de Sequência Molecular , Sequências Reguladoras de Ácido Nucleico/genética , Fatores de Transcrição/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Desoxirribonuclease I/metabolismo , Impressão Genômica , Genômica , Humanos , Polimorfismo de Nucleotídeo Único/genética , Sítio de Iniciação de Transcrição
15.
Phys Rev Lett ; 118(3): 032501, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-28157341

RESUMO

The first measurement of the low-lying states of the neutron-rich ^{110}Zr and ^{112}Mo was performed via in-beam γ-ray spectroscopy after one proton removal on hydrogen at ∼200 MeV/nucleon. The 2_{1}^{+} excitation energies were found at 185(11) keV in ^{110}Zr, and 235(7) keV in ^{112}Mo, while the R_{42}=E(4_{1}^{+})/E(2_{1}^{+}) ratios are 3.1(2), close to the rigid rotor value, and 2.7(1), respectively. These results are compared to modern energy density functional based configuration mixing models using Gogny and Skyrme effective interactions. We conclude that first levels of ^{110}Zr exhibit a rotational behavior, in agreement with previous observations of lighter zirconium isotopes as well as with the most advanced Monte Carlo shell model predictions. The data, therefore, do not support a harmonic oscillator shell stabilization scenario at Z=40 and N=70. The present data also invalidate predictions for a tetrahedral ground state symmetry in ^{110}Zr.

16.
Nature ; 460(7259): 1093-7, 2009 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-19657335

RESUMO

The contribution of changes in cis-regulatory elements or trans-acting factors to interspecies differences in gene expression is not well understood. The mammalian beta-globin loci have served as a model for gene regulation during development. Transgenic mice containing the human beta-globin locus, consisting of the linked embryonic (epsilon), fetal (gamma) and adult (beta) genes, have been used as a system to investigate the temporal switch from fetal to adult haemoglobin, as occurs in humans. Here we show that the human gamma-globin (HBG) genes in these mice behave as murine embryonic globin genes, revealing a limitation of the model and demonstrating that critical differences in the trans-acting milieu have arisen during mammalian evolution. We show that the expression of BCL11A, a repressor of human gamma-globin expression identified by genome-wide association studies, differs between mouse and human. Developmental silencing of the mouse embryonic globin and human gamma-globin genes fails to occur in mice in the absence of BCL11A. Thus, BCL11A is a critical mediator of species-divergent globin switching. By comparing the ontogeny of beta-globin gene regulation in mice and humans, we have shown that alterations in the expression of a trans-acting factor constitute a critical driver of gene expression changes during evolution.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Globinas/genética , Proteínas Nucleares/metabolismo , Animais , Proteínas de Transporte/genética , Proteínas de Ligação a DNA , Embrião de Mamíferos/metabolismo , Evolução Molecular , Feto/metabolismo , Inativação Gênica , Hematopoese , Humanos , Camundongos , Proteínas Nucleares/genética , Proteínas Repressoras , Especificidade da Espécie , Globinas beta/genética , gama-Globinas/genética
17.
N Engl J Med ; 365(9): 807-14, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21879898

RESUMO

BACKGROUND: An improved understanding of the regulation of the fetal hemoglobin genes holds promise for the development of targeted therapeutic approaches for fetal hemoglobin induction in the ß-hemoglobinopathies. Although recent studies have uncovered trans-acting factors necessary for this regulation, limited insight has been gained into the cis-regulatory elements involved. METHODS: We identified three families with unusual patterns of hemoglobin expression, suggestive of deletions in the locus of the ß-globin gene (ß-globin locus). We performed array comparative genomic hybridization to map these deletions and confirmed breakpoints by means of polymerase-chain-reaction assays and DNA sequencing. We compared these deletions, along with previously mapped deletions, and studied the trans-acting factors binding to these sites in the ß-globin locus by using chromatin immunoprecipitation. RESULTS: We found a new (δß)(0)-thalassemia deletion and a rare hereditary persistence of fetal hemoglobin deletion with identical downstream breakpoints. Comparison of the two deletions resulted in the identification of a small intergenic region required for γ-globin (fetal hemoglobin) gene silencing. We mapped a Kurdish ß(0)-thalassemia deletion, which retains the required intergenic region, deletes other surrounding sequences, and maintains fetal hemoglobin silencing. By comparing these deletions and other previously mapped deletions, we elucidated a 3.5-kb intergenic region near the 5' end of the δ-globin gene that is necessary for γ-globin silencing. We found that a critical fetal hemoglobin silencing factor, BCL11A, and its partners bind within this region in the chromatin of adult erythroid cells. CONCLUSIONS: By studying three families with unusual deletions in the ß-globin locus, we identified an intergenic region near the δ-globin gene that is necessary for fetal hemoglobin silencing. (Funded by the National Institutes of Health and others.).


Assuntos
Hemoglobina Fetal/genética , Regulação da Expressão Gênica , Globinas beta/genética , Talassemia beta/genética , Adulto , Criança , Montagem e Desmontagem da Cromatina , Feminino , Deleção de Genes , Inativação Gênica , Humanos , Masculino , Linhagem , Fenótipo , Transativadores
18.
Ann Oncol ; 25(5): 1004-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24562447

RESUMO

BACKGROUND: Guidelines for the use of chemotherapy and endocrine therapy recently recommended that estrogen receptor (ER) status be considered positive if ≥1% of tumor cells demonstrate positive nuclear staining by immunohistochemistry. In clinical practice, a range of thresholds are used; a common one is 10% positivity. Data addressing the optimal threshold with regard to the efficacy of endocrine therapy are lacking. In this study, we compared patient, tumor, treatment and survival differences among breast cancer patients using ER-positivity thresholds of 1% and 10%. METHODS: The study population consisted of patients with primary breast carcinoma treated at our center from January 1990 to December 2011 and whose records included complete data on ER status. Patients were separated into three groups: ≥10% positive staining for ER (ER-positive ≥10%), 1%-9% positive staining for ER (ER-positive 1%-9%) and <1% positive staining (ER-negative). RESULTS: Of 9639 patients included, 80.5% had tumors that were ER-positive ≥10%, 2.6% had tumors that were ER-positive 1%-9% and 16.9% had tumors that were ER-negative. Patients with ER-positive 1%-9% tumors were younger with more advanced disease compared with patients with ER-positive ≥10% tumors. At a median follow-up of 5.1 years, patients with ER-positive 1%-9% tumors had worse survival rates than did patients with ER-positive ≥10% tumors, with and without adjustment for clinical stage and grade. Survival rates did not differ significantly between patients with ER-positive 1%-9% and ER-negative tumors. CONCLUSIONS: Patients with tumors that are ER-positive 1%-9% have clinical and pathologic characteristics different from those with tumors that are ER-positive ≥10%. Similar to patients with ER-negative tumors, those with ER-positive 1%-9% disease do not appear to benefit from endocrine therapy; further study of its clinical benefit in this group is warranted. Also, there is a need to better define which patients of this group belong to basal or luminal subtypes.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Receptores de Estrogênio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/classificação , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/classificação , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/terapia , Carcinoma Intraductal não Infiltrante/classificação , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/terapia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Adulto Jovem
19.
Blood ; 119(16): 3820-7, 2012 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-22378846

RESUMO

The ß-globin locus control region (LCR) is necessary for high-level ß-globin gene transcription and differentiation-dependent relocation of the ß-globin locus from the nuclear periphery to the central nucleoplasm and to foci of hyperphosphorylated Pol II "transcription factories" (TFys). To determine the contribution of individual LCR DNaseI hypersensitive sites (HSs) to transcription and nuclear location, in the present study, we compared ß-globin gene activity and location in erythroid cells derived from mice with deletions of individual HSs, deletions of 2 HSs, and deletion of the whole LCR and found all of the HSs had a similar spectrum of activities, albeit to different degrees. Each HS acts as an independent module to activate expression in an additive manner, and this is correlated with relocation away from the nuclear periphery. In contrast, HSs have redundant activities with respect to association with TFys and the probability that an allele is actively transcribed, as measured by primary RNA transcript FISH. The limiting effect on RNA levels occurs after ß-globin genes associate with TFys, at which time HSs contribute to the amount of RNA arising from each burst of transcription by stimulating transcriptional elongation.


Assuntos
Núcleo Celular/metabolismo , Região de Controle de Locus Gênico/genética , Nucleoplasminas/metabolismo , Transcrição Gênica/fisiologia , Globinas beta/genética , Animais , Células Eritroides/metabolismo , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Camundongos Transgênicos , RNA Mensageiro/genética , Globinas beta/metabolismo
20.
Phys Rev Lett ; 113(16): 162501, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25361253

RESUMO

Beyond mean-field methods are very successful tools for the description of large-amplitude collective motion for even-even atomic nuclei. The state-of-the-art framework of these methods consists in a generator coordinate method based on angular-momentum and particle-number projected triaxially deformed Hartree-Fock-Bogoliubov (HFB) states. The extension of this scheme to odd-mass nuclei is a long-standing challenge. We present for the first time such an extension, where the generator coordinate space is built from self-consistently blocked one-quasiparticle HFB states. One of the key points for this success is that the same Skyrme interaction is used for the mean-field and the pairing channels, thus avoiding problems related to the violation of the Pauli principle. An application to ^{25}Mg illustrates the power of our method, as agreement with experiment is obtained for the spectrum, electromagnetic moments, and transition strengths, for both positive and negative parity states and without the necessity for effective charges or effective moments. Although the effective interaction still requires improvement, our study opens the way to systematically describe odd-A nuclei throughout the nuclear chart.

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