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1.
Mol Cell ; 81(6): 1260-1275.e12, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33561390

RESUMO

DNA methylation is implicated in neuronal biology via the protein MeCP2, the mutation of which causes Rett syndrome. MeCP2 recruits the NCOR1/2 co-repressor complexes to methylated cytosine in the CG dinucleotide, but also to sites of non-CG methylation, which are abundant in neurons. To test the biological significance of the dual-binding specificity of MeCP2, we replaced its DNA binding domain with an orthologous domain from MBD2, which can only bind mCG motifs. Knockin mice expressing the domain-swap protein displayed severe Rett-syndrome-like phenotypes, indicating that normal brain function requires the interaction of MeCP2 with sites of non-CG methylation, specifically mCAC. The results support the notion that the delayed onset of Rett syndrome is due to the simultaneous post-natal accumulation of mCAC and its reader MeCP2. Intriguingly, genes dysregulated in both Mecp2 null and domain-swap mice are implicated in other neurological disorders, potentially highlighting targets of relevance to the Rett syndrome phenotype.


Assuntos
Metilação de DNA , Proteína 2 de Ligação a Metil-CpG/metabolismo , Neurônios/metabolismo , Animais , Ilhas de CpG , Técnicas de Introdução de Genes , Células HeLa , Humanos , Masculino , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Camundongos Transgênicos , Mutação , Células NIH 3T3 , Neurônios/patologia , Domínios Proteicos , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Síndrome de Rett/patologia
2.
Nature ; 582(7810): 119-123, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494069

RESUMO

The three-dimensional architecture of the genome governs its maintenance, expression and transmission. The cohesin protein complex organizes the genome by topologically linking distant loci, and is highly enriched in specialized chromosomal domains surrounding centromeres, called pericentromeres1-6. Here we report the three-dimensional structure of pericentromeres in budding yeast (Saccharomyces cerevisiae) and establish the relationship between genome organization and function. We find that convergent genes mark pericentromere borders and, together with core centromeres, define their structure and function by positioning cohesin. Centromeres load cohesin, and convergent genes at pericentromere borders trap it. Each side of the pericentromere is organized into a looped conformation, with border convergent genes at the base. Microtubule attachment extends a single pericentromere loop, size-limited by convergent genes at its borders. Reorienting genes at borders into a tandem configuration repositions cohesin, enlarges the pericentromere and impairs chromosome biorientation during mitosis. Thus, the linear arrangement of transcriptional units together with targeted cohesin loading shapes pericentromeres into a structure that is competent for chromosome segregation. Our results reveal the architecture of the chromosomal region within which kinetochores are embedded, as well as the restructuring caused by microtubule attachment. Furthermore, we establish a direct, causal relationship between the three-dimensional genome organization of a specific chromosomal domain and cellular function.


Assuntos
Centrômero/genética , Centrômero/metabolismo , Genes Fúngicos , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Proteínas de Ciclo Celular/metabolismo , Centrômero/química , Proteínas Cromossômicas não Histona/metabolismo , Segregação de Cromossomos , Genoma Fúngico/genética , Viabilidade Microbiana/genética , Mitose/genética , Conformação Molecular , Coesinas
3.
N Engl J Med ; 387(7): 620-630, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35830653

RESUMO

BACKGROUND: Human adenoviruses typically cause self-limited respiratory, gastrointestinal, and conjunctival infections in healthy children. In late 2021 and early 2022, several previously healthy children were identified with acute hepatitis and human adenovirus viremia. METHODS: We used International Classification of Diseases, 10th Revision, codes to identify all children (<18 years of age) with hepatitis who were admitted to Children's of Alabama hospital between October 1, 2021, and February 28, 2022; those with acute hepatitis who also tested positive for human adenovirus by whole-blood quantitative polymerase chain reaction (PCR) were included in our case series. Demographic, clinical, laboratory, and treatment data were obtained from medical records. Residual blood specimens were sent for diagnostic confirmation and human adenovirus typing. RESULTS: A total of 15 children were identified with acute hepatitis - 6 (40%) who had hepatitis with an identified cause and 9 (60%) who had hepatitis without a known cause. Eight (89%) of the patients with hepatitis of unknown cause tested positive for human adenovirus. These 8 patients plus 1 additional patient referred to this facility for follow-up were included in this case series (median age, 2 years 11 months; age range, 1 year 1 month to 6 years 5 months). Liver biopsies indicated mild-to-moderate active hepatitis in 6 children, some with and some without cholestasis, but did not show evidence of human adenovirus on immunohistochemical examination or electron microscopy. PCR testing of liver tissue for human adenovirus was positive in 3 children (50%). Sequencing of specimens from 5 children showed three distinct human adenovirus type 41 hexon variants. Two children underwent liver transplantation; all the others recovered with supportive care. CONCLUSIONS: Human adenovirus viremia was present in the majority of children with acute hepatitis of unknown cause admitted to Children's of Alabama from October 1, 2021, to February 28, 2022, but whether human adenovirus was causative remains unclear. Sequencing results suggest that if human adenovirus was causative, this was not an outbreak driven by a single strain. (Funded in part by the Centers for Disease Control and Prevention.).


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Hepatite , Doença Aguda , Infecções por Adenovirus Humanos/complicações , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Criança , Pré-Escolar , Hepatite/virologia , Humanos , Lactente , Viremia
4.
Hum Genomics ; 17(1): 64, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454130

RESUMO

BACKGROUND: Female breast cancer remains the second leading cause of cancer-related death in the USA. The heterogeneity in the tumor morphology across the cohort and within patients can lead to unpredictable therapy resistance, metastasis, and clinical outcome. Hence, supplementing classic pathological markers with intrinsic tumor molecular markers can help identify novel molecular subtypes and the discovery of actionable biomarkers. METHODS: We conducted a large multi-institutional genomic analysis of paired normal and tumor samples from breast cancer patients to profile the complex genomic architecture of breast tumors. Long-term patient follow-up, therapeutic regimens, and treatment response for this cohort are documented using the Breast Cancer Collaborative Registry. The majority of the patients in this study were at tumor stage 1 (51.4%) and stage 2 (36.3%) at the time of diagnosis. Whole-exome sequencing data from 554 patients were used for mutational profiling and identifying cancer drivers. RESULTS: We identified 54 tumors having at least 1000 mutations and 185 tumors with less than 100 mutations. Tumor mutational burden varied across the classified subtypes, and the top ten mutated genes include MUC4, MUC16, PIK3CA, TTN, TP53, NBPF10, NBPF1, CDC27, AHNAK2, and MUC2. Patients were classified based on seven biological and tumor-specific parameters, including grade, stage, hormone receptor status, histological subtype, Ki67 expression, lymph node status, race, and mutational profiles compared across different subtypes. Mutual exclusion of mutations in PIK3CA and TP53 was pronounced across different tumor grades. Cancer drivers specific to each subtype include TP53, PIK3CA, CDC27, CDH1, STK39, CBFB, MAP3K1, and GATA3, and mutations associated with patient survival were identified in our cohort. CONCLUSIONS: This extensive study has revealed tumor burden, driver genes, co-occurrence, mutual exclusivity, and survival effects of mutations on a US Midwestern breast cancer cohort, paving the way for developing personalized therapeutic strategies.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Prognóstico , Mutação , Biomarcadores Tumorais/genética , Classe I de Fosfatidilinositol 3-Quinases/genética
5.
J Anim Ecol ; 93(1): 57-70, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975479

RESUMO

The island species-area relationship (ISAR) describes how species richness increases with increasing area of a given island or island-like habitat, such as freshwater lakes. While the ISAR is one of the most common phenomena observed in ecology, there is variation in both the form of the relationship and its underlying mechanisms. We compiled a global data set of benthic macroinvertebrates from 524 shallow freshwater lakes, ranging from 1 to 293,300 ha in area. We used individual-based rarefaction to determine the degree to which ISAR was influenced by mechanisms other than passive sampling (larger islands passively sample more individuals from the regional pool and, therefore, have more species than smaller islands), which would bias results away from expected relationships between rarefied species richness (and other measures that capture relative abundances) and lake area. We also examined how climate may alter the shape of the ISARs. We found that both rarefied species richness (the number of species standardized by area or number of individuals) and a measure of evenness emphasizing common species exhibit shallow slopes in relationships with lake area, suggesting that the expected ISARs in these lakes most likely result from passive sampling. While there was considerable variation among ISARs across the investigated lakes, we found an overall positive rarefied ISAR for lakes in warm (i.e. tropical/subtropical) regions (n = 195), and in contrast, an overall negative rarefied ISAR in cool (i.e. north temperate) lakes (n = 329). This suggested that mechanisms beyond passive sampling (e.g. colonization-extinction dynamics and/or heterogeneity) were more likely to operate in warm lakes. One possible reason for this difference is that the area-dependent intensity of fish predation, which can lead to flatter ISARs, is weaker in warmer relative to cooler lakes. Our study illustrates the importance of understanding both the pattern and potential processes underlying the ISARs of freshwater lakes in different climatic regions. Furthermore, it provides a baseline for understanding how further changes to the ecosystem (i.e. in lake area or climate) might influence biodiversity patterns.


Assuntos
Biodiversidade , Ecossistema , Animais , Lagos , Peixes , Ecologia
6.
Mol Cell ; 62(6): 834-847, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27264872

RESUMO

Whether gene repositioning to the nuclear periphery during differentiation adds another layer of regulation to gene expression remains controversial. Here, we resolve this by manipulating gene positions through targeting the nuclear envelope transmembrane proteins (NETs) that direct their normal repositioning during myogenesis. Combining transcriptomics with high-resolution DamID mapping of nuclear envelope-genome contacts, we show that three muscle-specific NETs, NET39, Tmem38A, and WFS1, direct specific myogenic genes to the nuclear periphery to facilitate their repression. Retargeting a NET39 fragment to nucleoli correspondingly repositioned a target gene, indicating a direct tethering mechanism. Being able to manipulate gene position independently of other changes in differentiation revealed that repositioning contributes ⅓ to ⅔ of a gene's normal repression in myogenesis. Together, these NETs affect 37% of all genes changing expression during myogenesis, and their combined knockdown almost completely blocks myotube formation. This unequivocally demonstrates that NET-directed gene repositioning is critical for developmental gene regulation.


Assuntos
Posicionamento Cromossômico , Regulação da Expressão Gênica no Desenvolvimento , Canais Iônicos/genética , Proteínas de Membrana/genética , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/metabolismo , Mioblastos Esqueléticos/metabolismo , Membrana Nuclear/metabolismo , Proteínas Nucleares/genética , Animais , Diferenciação Celular , Linhagem Celular , Regulação para Baixo , Humanos , Canais Iônicos/metabolismo , Cinética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Nucleares/metabolismo , Interferência de RNA , Transfecção
7.
Biol Sport ; 41(1): 163-174, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38188097

RESUMO

This study investigated the association of physiological attributes with in-game workload measures during competitive Gaelic football match-play. Fifty-two male developmental level Gaelic football players (mean ± SD; age: 22.9 ± 3.8 years) underwent measurements of anthropometric characteristics, running speed, muscular strength and power, blood lactate (BLa), running economy and aerobic capacity during two separate testing visits. Global Positioning System units (18-Hz) were used to record players in-game workloads during a competitive match 1-week following the baseline physiological assessments. Results indicated that players body fat percentage, drop jump height (DJ) and running velocity at 4 mmol · L-1 BLa were significantly associated with the number of high-speed runs completed (Adjusted R2 26.8% to 39.5%; p < 0.05) while 20 m running speed, running velocity at 2 mmol · L-1 BLa and DJ were significantly associated with the number of accelerations completed (Adjusted R2 17.2% to 22.0%; p < 0.05) during match-play. Additionally, aerobic capacity and body fat percentage were significantly associated with total distance (Adjusted R2 14.4% to 22.4%; p < 0.05) while body fat percentage, DJ and 20 m running speed were significantly associated with high-speed distance (Adjusted R2 17.8% to 22.0%; p < 0.05). Players were also divided into higher-standard and lower-standard groups using a median split of these physiological attributes. Players in the higher-standard groups completed significantly more high-speed runs and accelerations and covered significantly larger total and high-speed distances (+10.4% to +36.8%; ES = 0.67 to 0.88; p < 0.05) when compared to the lower-standard groups. This study demonstrates that superior levels of physical conditioning are associated with larger in-game workloads during Gaelic football match-play.

8.
J Cell Sci ; 134(6)2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33602740

RESUMO

Movement of the cell nucleus typically involves the cytoskeleton and either polymerization-based pushing forces or motor-based pulling forces. In the fission yeast Schizosaccharomyces pombe, nuclear movement and positioning are thought to depend on microtubule polymerization-based pushing forces. Here, we describe a novel, microtubule-independent, form of nuclear movement in fission yeast. Microtubule-independent nuclear movement is directed towards growing cell tips, and it is strongest when the nucleus is close to a growing cell tip, and weakest when the nucleus is far from that tip. Microtubule-independent nuclear movement requires actin cables but does not depend on actin polymerization-based pushing or myosin V-based pulling forces. The vesicle-associated membrane protein (VAMP)-associated proteins (VAPs) Scs2 and Scs22, which are critical for endoplasmic reticulum-plasma membrane contact sites in fission yeast, are also required for microtubule-independent nuclear movement. We also find that in cells in which microtubule-based pushing forces are present, disruption of actin cables leads to increased fluctuations in interphase nuclear positioning and subsequent altered septation. Our results suggest two non-exclusive mechanisms for microtubule-independent nuclear movement, which may help illuminate aspects of nuclear positioning in other cells.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Núcleo Celular , Interfase , Microtúbulos , Proteínas de Schizosaccharomyces pombe/genética
9.
Nucleic Acids Res ; 49(11): 6456-6473, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34107032

RESUMO

RNA-protein interactions are central to all gene expression processes and contribute to a variety of human diseases. Therapeutic approaches targeting RNA-protein interactions have shown promising effects on some diseases that are previously regarded as 'incurable'. Here, we developed a fluorescent on-bead screening platform, RNA Pull-Down COnfocal NAnoscanning (RP-CONA), to identify RNA-protein interaction modulators in eukaryotic cell extracts. Using RP-CONA, we identified small molecules that disrupt the interaction between HuR, an inhibitor of brain-enriched miR-7 biogenesis, and the conserved terminal loop of pri-miR-7-1. Importantly, miR-7's primary target is an mRNA of α-synuclein, which contributes to the aetiology of Parkinson's disease. Our method identified a natural product quercetin as a molecule able to upregulate cellular miR-7 levels and downregulate the expression of α-synuclein. This opens up new therapeutic avenues towards treatment of Parkinson's disease as well as provides a novel methodology to search for modulators of RNA-protein interaction.


Assuntos
Proteína Semelhante a ELAV 1/antagonistas & inibidores , MicroRNAs/antagonistas & inibidores , Quercetina/farmacologia , alfa-Sinucleína/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Proteína Semelhante a ELAV 1/metabolismo , Células HEK293 , Células HeLa , Humanos , MicroRNAs/metabolismo , Microscopia Confocal , RNA Mensageiro/metabolismo , alfa-Sinucleína/genética
10.
Proc Natl Acad Sci U S A ; 117(20): 11018-11028, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32366649

RESUMO

Modern agriculture has dramatically changed the distribution of animal species on Earth. Changes to host ecology have a major impact on the microbiota, potentially increasing the risk of zoonotic pathogens being transmitted to humans, but the impact of intensive livestock production on host-associated bacteria has rarely been studied. Here, we use large isolate collections and comparative genomics techniques, linked to phenotype studies, to understand the timescale and genomic adaptations associated with the proliferation of the most common food-born bacterial pathogen (Campylobacter jejuni) in the most prolific agricultural mammal (cattle). Our findings reveal the emergence of cattle specialist C. jejuni lineages from a background of host generalist strains that coincided with the dramatic rise in cattle numbers in the 20th century. Cattle adaptation was associated with horizontal gene transfer and significant gene gain and loss. This may be related to differences in host diet, anatomy, and physiology, leading to the proliferation of globally disseminated cattle specialists of major public health importance. This work highlights how genomic plasticity can allow important zoonotic pathogens to exploit altered niches in the face of anthropogenic change and provides information for mitigating some of the risks posed by modern agricultural systems.


Assuntos
Agricultura , Campylobacter jejuni/genética , Campylobacter jejuni/fisiologia , Especificidade de Hospedeiro , Especialização , Adaptação Fisiológica/genética , Animais , Biofilmes , Bovinos/microbiologia , Bovinos/fisiologia , Dieta , Evolução Molecular , Transferência Genética Horizontal , Genômica , Recombinação Homóloga , Interações Hidrofóbicas e Hidrofílicas , Mutagênese , Fenótipo , Recombinação Genética
11.
Fetal Pediatr Pathol ; 42(2): 241-252, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36062956

RESUMO

Background: Ewing sarcoma (ES) can be confirmed by identifying the EWSR1-FLI1 fusion transcript. This study is to investigate whether immunostaining (IHC) of PRKCB-a protein directly regulated by EWSR1-FLI1 is a surrogate maker for diagnosing ES in routine practice. Methods: Microarray gene expression analyses were conducted. RKCB IHC was applied to 69 ES confirmed by morphology and molecular methods, and 41 non-Ewing small round cell tumors. EWSR1 rearrangement, EWSR1-FLI1 fusion or t(11;22)(q24;q12) were identified by fluorescence in situ hybridization, reverse transcriptase polymerase chain reaction, or cytogenetic analysis, respectively. Results: Gene array analyses showed significant overexpression of the PRKCB in ES. PRKCB IHC was positive in 19 cases of ES with EWSR1-FLI1 fusion, 3 cases with cytogenetic 11:22 translocation and 59 cases with EWSR1 rearrangement while negative in only one EWSR1 rearranged case. PRKCB IHC is sensitive (98%) and specific (96%) in detecting EWSR1 rearranged ES. Conclusions: PRKCB is a reliable antibody for diagnosing ES in routine practice.


Assuntos
Sarcoma de Ewing , Sarcoma , Humanos , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/genética , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Proteína EWS de Ligação a RNA/genética , Biomarcadores , Proteínas de Fusão Oncogênica/genética , Proteína Quinase C beta/genética , Proteína Quinase C beta/metabolismo
12.
J Bacteriol ; 204(1): e0042121, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34606373

RESUMO

The paralogues RrpA and RrpB, which are members of the MarR family of DNA binding proteins, are important for the survival of the global bacterial foodborne pathogen Campylobacter jejuni under redox stress. We report that RrpA is a positive regulator of mdaB, encoding a flavin-dependent quinone reductase that contributes to the protection from redox stress mediated by structurally diverse quinones, while RrpB negatively regulates the expression of cj1555c (renamed nfrA for NADPH-flavin reductase A), encoding a flavin reductase. NfrA reduces riboflavin at a greater rate than its derivatives, suggesting that exogenous free flavins are the natural substrate. MdaB and NfrA both prefer NADPH as an electron donor. Cysteine substitution and posttranslational modification analyses indicated that RrpA and RrpB employ a cysteine-based redox switch. Complete genome sequence analyses revealed that mdaB is frequently found in Campylobacter and related Helicobacter spp., while nfrA is predominant in C. jejuni strains. Quinones and flavins are redox cycling agents secreted by a wide range of cell types that can form damaging superoxide by one-electron reactions. We propose a model for stress adaptation where MdaB and NfrA facilitate a two-electron reduction mechanism to the less toxic hydroquinones, thus aiding survival and persistence of this major pathogen. IMPORTANCE Changes in cellular redox potential result in alteration in the oxidation state of intracellular metabolites and enzymes; consequently, cells make adjustments that favor growth and survival. The work we present here answers some of the many questions that have remained elusive over the years of investigation into the enigmatic microaerophile bacterium Campylobacter jejuni. We employed molecular approaches to understand the regulation mechanisms and functional analyses to reveal the roles of two novel quinone and flavin reductases; both serve as major pools of cellular redox-active molecules. This work extends our knowledge on bacterial redox sensing mechanisms and the significance of hemostasis.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Helicobacter pylori/enzimologia , Oxirredutases/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Flavinas/metabolismo , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Oxirredutases/genética , Quinonas/metabolismo
13.
Ecol Lett ; 25(3): 581-597, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35199922

RESUMO

Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species-level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity.


Assuntos
Aves , Ecossistema , Animais , Biodiversidade , Evolução Biológica , Humanos , Filogenia
14.
Mol Microbiol ; 116(1): 343-358, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33721378

RESUMO

Campylobacter jejuni is a microaerophilic zoonotic pathogen with an atypical respiratory Complex I that oxidizes a flavodoxin (FldA) instead of NADH. FldA is essential for viability and is reduced via pyruvate and 2-oxoglutarate oxidoreductases (POR/OOR). Here, we show that FldA can also be reduced by FqrB (Cj0559), an NADPH:FldA reductase. An fqrB deletion mutant was viable but displayed a significant growth defect. FqrB is related to flavoprotein reductases from Gram-positive bacteria that can reduce NrdI, a specialized flavodoxin that is needed for tyrosyl radical formation in NrdF, the beta subunit of class 1b-type (Mn) ribonucleotide reductase (RNR). However, C. jejuni possesses a single class Ia-type (Fe) RNR (NrdAB) that would be expected to be ferredoxin dependent. We show that CjFldA is an unusually high potential flavodoxin unrelated to NrdI, yet growth of the fqrB mutant, but not the wild-type or a complemented strain, was stimulated by low deoxyribonucleoside (dRNS) concentrations, suggesting FldA links FqrB and RNR activity. Using purified proteins, we confirmed the NrdB tyrosyl radical could be regenerated in an NADPH, FqrB, and FldA dependent manner, as evidenced by both optical and electron paramagnetic resonance (EPR) spectroscopy. Thus, FldA activates RNR in C. jejuni, partly explaining its essentiality.


Assuntos
Proteínas de Bactérias/metabolismo , Campylobacter jejuni/metabolismo , Flavodoxina/metabolismo , Flavoproteínas/metabolismo , NADH NADPH Oxirredutases/metabolismo , Ribonucleosídeo Difosfato Redutase/metabolismo , Oxirredutases do Álcool/metabolismo , Campylobacter jejuni/enzimologia , Campylobacter jejuni/genética , Deleção de Genes , Oxirredução , Piruvato Sintase/metabolismo , Ribonucleotídeo Redutases/metabolismo
15.
Metab Eng ; 72: 133-149, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35289291

RESUMO

Robust systematic approaches for the metabolic engineering of cell factories remain elusive. The available models for predicting phenotypical responses and mechanisms are incomplete, particularly within the context of compound toxicity that can be a significant impediment to achieving high yields of a target product. This study describes a Multi-Omic Based Production Strain Improvement (MOBpsi) strategy that is distinguished by integrated time-resolved systems analyses of fed-batch fermentations. As a case study, MOBpsi was applied to improve the performance of an Escherichia coli cell factory producing the commodity chemical styrene. Styrene can be bio-manufactured from phenylalanine via an engineered pathway comprised of the enzymes phenylalanine ammonia lyase and ferulic acid decarboxylase. The toxicity, hydrophobicity, and volatility of styrene combine to make bio-production challenging. Previous attempts to create styrene tolerant E. coli strains by targeted genetic interventions have met with modest success. Application of MOBpsi identified new potential targets for improving performance, resulting in two host strains (E. coli NST74ΔaaeA and NST74ΔaaeA cpxPo) with increased styrene production. The best performing re-engineered chassis, NST74ΔaaeA cpxPo, produced ∼3 × more styrene and exhibited increased viability in fed-batch fermentations. Thus, this case study demonstrates the utility of MOBpsi as a systematic tool for improving the bio-manufacturing of toxic chemicals.


Assuntos
Escherichia coli , Engenharia Metabólica , Escherichia coli/metabolismo , Fermentação , Engenharia Metabólica/métodos , Fenilalanina/genética , Fenilalanina/metabolismo , Estireno/metabolismo
16.
MMWR Morb Mortal Wkly Rep ; 71(18): 638-640, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35511732

RESUMO

During October-November 2021, clinicians at a children's hospital in Alabama identified five pediatric patients with severe hepatitis and adenovirus viremia upon admission. In November 2021, hospital clinicians, the Alabama Department of Public Health, the Jefferson County Department of Health, and CDC began an investigation. This activity was reviewed by CDC and conducted consistent with applicable federal law and CDC policy.


Assuntos
Infecções por Adenoviridae , Hepatite , Doença Aguda , Alabama/epidemiologia , Criança , Humanos , Saúde Pública
17.
Pediatr Blood Cancer ; 69(2): e29485, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34843167

RESUMO

Vascular anomalies comprise a spectrum of disorders characterized by the abnormal development or growth of blood and lymphatic vessels. These growths have unique features and diverse behaviors, mandating a multidisciplinary approach in their evaluation, diagnosis, and management. Here we describe the case of a male toddler presenting with an abdominal mass, originally treated as a metastatic retroperitoneal tumor, but subsequently felt to represent a vascular anomaly.


Assuntos
Hemangioma , Neoplasias Retroperitoneais , Malformações Vasculares , Hemangioma/patologia , Hemangioma/terapia , Humanos , Masculino , Malformações Vasculares/terapia
18.
Dev Sci ; 25(2): e13182, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34633123

RESUMO

Facial expressions are one way in which infants and adults communicate emotion. Infants scan expressions similarly to adults, yet it remains unclear whether they are receptive to the affective information they convey. The current study investigates 6-, 9- and 12-month infants' (N = 146) pupillary responses to the six "basic" emotional expressions (happy, sad, surprise, fear, anger, and disgust). To do this we use dynamic stimuli and gaze-contingent eye-tracking to simulate brief interactive exchanges, alongside a static control condition. Infants' arousal responses were stronger for dynamic compared to static stimuli. And for dynamic stimuli we found that, compared to neutral, infants showed dilatory responses for happy and angry expressions only. Although previous work has shown infants can discriminate perceptually between facial expressions, our data suggest that sensitivity to the affective content of all six basic emotional expressions may not fully emerge until later in ontogeny.


Assuntos
Expressão Facial , Pupila , Adulto , Ira , Emoções/fisiologia , Felicidade , Humanos , Lactente
19.
Oecologia ; 200(3-4): 285-294, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35962285

RESUMO

Male and female reproductive behaviour is typically synchronised. In species such as those in the family Cervidae, reproductive timing is often cued by photoperiod, although in females, it can be dependent on body condition. When a species is introduced to a novel environment, the environment changes, or responses of the sexes to such cues differ, asynchronous reproductive behaviour between males and females may occur. We investigated the seasonality of reproductive behaviour in introduced chital deer in northern Queensland by examining male antler phase in relation to female conception rates. We then analysed the influence of different variables likely to affect the timing of male and female reproductive physiology. The lowest percentage of chital in hard antler in any 1 month in this study was 35% (Fig. 1), but the average value was closer to 50%, thus there was a seasonal peak in antler phase linked with photoperiod. Females conceived at any time of year, but were strongly influenced by the amount of rainfall 3 months prior to conception. This resulted in varying conception peaks year-to-year that often did not correspond to the male's peak in hard antler. In this system, a proportion of males and females were physiologically and behaviourally ready to mate at any time of the year. We predict that differences in the timing of the peaks between the males and females will lead to increased reproductive skew (variation in reproductive success among individual males). This pattern may select for different mating strategies or physiological mechanisms to increase reproductive success. Fig. 1 The average percentage of male chital deer in hard antler by month from 2014 to 2019 in north Queensland. Values above the bars indicate the total number of males that were sampled in each month and the error bars indicate the standard error. In the month with the lowest % males in hard antler in the entire study (November, 2017), 35% of males were in hard antler.


Assuntos
Cervos , Animais , Feminino , Masculino , Reprodução , Fertilização , Sinais (Psicologia)
20.
J Pediatr Hematol Oncol ; 44(1): e109-e113, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33625084

RESUMO

Therapy-related myeloid neoplasm (t-MN) in the pediatric population is not well characterized. We studied 12 pediatric patients diagnosed with t-MN in our institution since 2006. The median age at the t-MN diagnoses was 14.8 years (range, 9 to 20 y). The primary malignancies included 9 solid tumors and 3 hematopoietic malignancies. Rhabdomyosarcoma (n=4) was the most common primary malignancy. Five of the 9 patients with solid tumors and all 3 patients with hematopoietic malignancies had primary neoplasms involving bone marrow. The median latency period was 5.2 years (range, 1.8 to 13.8 y). Thrombocytopenia was present in all patients at the t-MN diagnoses. Complete or partial monosomy of chromosome 5 or 7 were the 2 most common cytogenetic abnormalities. A quarter of patients demonstrated a genetic predisposition to t-MN: 1 with Li-Fraumeni syndrome with a germline TP53 R248Q mutation, 1 with Noonan syndrome with a somatic mutation (PTPN11 S502T), and 1 with a constitutive chromosomal translocation [t(X;9)(p22;q34)] and a germline TP53 L130V mutation. Outcomes remain poor. Two patients survived 3 and 5.1 years after hematopoietic stem cell transplantation.


Assuntos
Cromossomos Humanos Par 5/genética , Predisposição Genética para Doença , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Síndrome de Li-Fraumeni , Transtornos Mieloproliferativos , Segunda Neoplasia Primária , Síndrome de Noonan , Rabdomiossarcoma , Adolescente , Adulto , Aloenxertos , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 7/genética , Feminino , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/genética , Humanos , Lactente , Síndrome de Li-Fraumeni/epidemiologia , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/terapia , Masculino , Transtornos Mieloproliferativos/epidemiologia , Transtornos Mieloproliferativos/genética , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/genética , Síndrome de Noonan/epidemiologia , Síndrome de Noonan/genética , Síndrome de Noonan/terapia , Rabdomiossarcoma/epidemiologia , Rabdomiossarcoma/genética , Rabdomiossarcoma/terapia , Adulto Jovem
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