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1.
Cell ; 187(2): 390-408.e23, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38157855

RESUMO

We describe a human lung disease caused by autosomal recessive, complete deficiency of the monocyte chemokine receptor C-C motif chemokine receptor 2 (CCR2). Nine children from five independent kindreds have pulmonary alveolar proteinosis (PAP), progressive polycystic lung disease, and recurrent infections, including bacillus Calmette Guérin (BCG) disease. The CCR2 variants are homozygous in six patients and compound heterozygous in three, and all are loss-of-expression and loss-of-function. They abolish CCR2-agonist chemokine C-C motif ligand 2 (CCL-2)-stimulated Ca2+ signaling in and migration of monocytic cells. All patients have high blood CCL-2 levels, providing a diagnostic test for screening children with unexplained lung or mycobacterial disease. Blood myeloid and lymphoid subsets and interferon (IFN)-γ- and granulocyte-macrophage colony-stimulating factor (GM-CSF)-mediated immunity are unaffected. CCR2-deficient monocytes and alveolar macrophage-like cells have normal gene expression profiles and functions. By contrast, alveolar macrophage counts are about half. Human complete CCR2 deficiency is a genetic etiology of PAP, polycystic lung disease, and recurrent infections caused by impaired CCL2-dependent monocyte migration to the lungs and infected tissues.


Assuntos
Proteinose Alveolar Pulmonar , Receptores CCR2 , Criança , Humanos , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Proteinose Alveolar Pulmonar/genética , Proteinose Alveolar Pulmonar/diagnóstico , Receptores CCR2/deficiência , Receptores CCR2/genética , Receptores CCR2/metabolismo , Reinfecção/metabolismo
2.
Cell ; 186(18): 3776-3792.e16, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37478861

RESUMO

In vitro stem cell models that replicate human gastrulation have been generated, but they lack the essential extraembryonic cells needed for embryonic development, morphogenesis, and patterning. Here, we describe a robust and efficient method that prompts human extended pluripotent stem cells to self-organize into embryo-like structures, termed peri-gastruloids, which encompass both embryonic (epiblast) and extraembryonic (hypoblast) tissues. Although peri-gastruloids are not viable due to the exclusion of trophoblasts, they recapitulate critical stages of human peri-gastrulation development, such as forming amniotic and yolk sac cavities, developing bilaminar and trilaminar embryonic discs, specifying primordial germ cells, initiating gastrulation, and undergoing early neurulation and organogenesis. Single-cell RNA-sequencing unveiled transcriptomic similarities between advanced human peri-gastruloids and primary peri-gastrulation cell types found in humans and non-human primates. This peri-gastruloid platform allows for further exploration beyond gastrulation and may potentially aid in the development of human fetal tissues for use in regenerative medicine.


Assuntos
Implantação do Embrião , Gastrulação , Células-Tronco Pluripotentes , Animais , Feminino , Humanos , Gravidez , Diferenciação Celular , Embrião de Mamíferos , Desenvolvimento Embrionário , Organogênese , Células-Tronco Pluripotentes/metabolismo , Primatas
3.
Cell ; 186(23): 5114-5134.e27, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37875108

RESUMO

Human inherited disorders of interferon-gamma (IFN-γ) immunity underlie severe mycobacterial diseases. We report X-linked recessive MCTS1 deficiency in men with mycobacterial disease from kindreds of different ancestries (from China, Finland, Iran, and Saudi Arabia). Complete deficiency of this translation re-initiation factor impairs the translation of a subset of proteins, including the kinase JAK2 in all cell types tested, including T lymphocytes and phagocytes. JAK2 expression is sufficiently low to impair cellular responses to interleukin-23 (IL-23) and partially IL-12, but not other JAK2-dependent cytokines. Defective responses to IL-23 preferentially impair the production of IFN-γ by innate-like adaptive mucosal-associated invariant T cells (MAIT) and γδ T lymphocytes upon mycobacterial challenge. Surprisingly, the lack of MCTS1-dependent translation re-initiation and ribosome recycling seems to be otherwise physiologically redundant in these patients. These findings suggest that X-linked recessive human MCTS1 deficiency underlies isolated mycobacterial disease by impairing JAK2 translation in innate-like adaptive T lymphocytes, thereby impairing the IL-23-dependent induction of IFN-γ.


Assuntos
Interferon gama , Janus Quinase 2 , Infecções por Mycobacterium , Humanos , Masculino , Proteínas de Ciclo Celular/metabolismo , Interferon gama/imunologia , Interleucina-12 , Interleucina-23 , Janus Quinase 2/metabolismo , Mycobacterium/fisiologia , Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/metabolismo , Proteínas Oncogênicas/metabolismo
5.
Cell ; 175(6): 1533-1545.e20, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30415838

RESUMO

Budding yeasts (subphylum Saccharomycotina) are found in every biome and are as genetically diverse as plants or animals. To understand budding yeast evolution, we analyzed the genomes of 332 yeast species, including 220 newly sequenced ones, which represent nearly one-third of all known budding yeast diversity. Here, we establish a robust genus-level phylogeny comprising 12 major clades, infer the timescale of diversification from the Devonian period to the present, quantify horizontal gene transfer (HGT), and reconstruct the evolution of 45 metabolic traits and the metabolic toolkit of the budding yeast common ancestor (BYCA). We infer that BYCA was metabolically complex and chronicle the tempo and mode of genomic and phenotypic evolution across the subphylum, which is characterized by very low HGT levels and widespread losses of traits and the genes that control them. More generally, our results argue that reductive evolution is a major mode of evolutionary diversification.


Assuntos
Evolução Molecular , Transferência Genética Horizontal , Genoma Fúngico , Filogenia , Saccharomycetales/classificação , Saccharomycetales/genética
6.
Cell ; 175(5): 1244-1258.e26, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30454645

RESUMO

Cyclin-dependent kinase 9 (CDK9) promotes transcriptional elongation through RNAPII pause release. We now report that CDK9 is also essential for maintaining gene silencing at heterochromatic loci. Through a live cell drug screen with genetic confirmation, we discovered that CDK9 inhibition reactivates epigenetically silenced genes in cancer, leading to restored tumor suppressor gene expression, cell differentiation, and activation of endogenous retrovirus genes. CDK9 inhibition dephosphorylates the SWI/SNF protein BRG1, which contributes to gene reactivation. By optimization through gene expression, we developed a highly selective CDK9 inhibitor (MC180295, IC50 = 5 nM) that has broad anti-cancer activity in vitro and is effective in in vivo cancer models. Additionally, CDK9 inhibition sensitizes to the immune checkpoint inhibitor α-PD-1 in vivo, making it an excellent target for epigenetic therapy of cancer.


Assuntos
Quinase 9 Dependente de Ciclina/metabolismo , Animais , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/genética , DNA Helicases/genética , DNA Helicases/metabolismo , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Cell ; 168(5): 830-842.e7, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28235197

RESUMO

De novo copy number variants (dnCNVs) arising at multiple loci in a personal genome have usually been considered to reflect cancer somatic genomic instabilities. We describe a multiple dnCNV (MdnCNV) phenomenon in which individuals with genomic disorders carry five to ten constitutional dnCNVs. These CNVs originate from independent formation incidences, are predominantly tandem duplications or complex gains, exhibit breakpoint junction features reminiscent of replicative repair, and show increased de novo point mutations flanking the rearrangement junctions. The active CNV mutation shower appears to be restricted to a transient perizygotic period. We propose that a defect in the CNV formation process is responsible for the "CNV-mutator state," and this state is dampened after early embryogenesis. The constitutional MdnCNV phenomenon resembles chromosomal instability in various cancers. Investigations of this phenomenon may provide unique access to understanding genomic disorders, structural variant mutagenesis, human evolution, and cancer biology.


Assuntos
Aberrações Cromossômicas , Variações do Número de Cópias de DNA , Doenças Genéticas Inatas/embriologia , Doenças Genéticas Inatas/genética , Instabilidade Genômica , Mutação , Pontos de Quebra do Cromossomo , Duplicação Cromossômica , Replicação do DNA , Desenvolvimento Embrionário , Feminino , Gametogênese , Humanos , Masculino
8.
Nature ; 626(7999): 555-564, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356065

RESUMO

The possibility that the Amazon forest system could soon reach a tipping point, inducing large-scale collapse, has raised global concern1-3. For 65 million years, Amazonian forests remained relatively resilient to climatic variability. Now, the region is increasingly exposed to unprecedented stress from warming temperatures, extreme droughts, deforestation and fires, even in central and remote parts of the system1. Long existing feedbacks between the forest and environmental conditions are being replaced by novel feedbacks that modify ecosystem resilience, increasing the risk of critical transition. Here we analyse existing evidence for five major drivers of water stress on Amazonian forests, as well as potential critical thresholds of those drivers that, if crossed, could trigger local, regional or even biome-wide forest collapse. By combining spatial information on various disturbances, we estimate that by 2050, 10% to 47% of Amazonian forests will be exposed to compounding disturbances that may trigger unexpected ecosystem transitions and potentially exacerbate regional climate change. Using examples of disturbed forests across the Amazon, we identify the three most plausible ecosystem trajectories, involving different feedbacks and environmental conditions. We discuss how the inherent complexity of the Amazon adds uncertainty about future dynamics, but also reveals opportunities for action. Keeping the Amazon forest resilient in the Anthropocene will depend on a combination of local efforts to end deforestation and degradation and to expand restoration, with global efforts to stop greenhouse gas emissions.


Assuntos
Florestas , Aquecimento Global , Árvores , Secas/estatística & dados numéricos , Retroalimentação , Aquecimento Global/prevenção & controle , Aquecimento Global/estatística & dados numéricos , Árvores/crescimento & desenvolvimento , Incêndios Florestais/estatística & dados numéricos , Incerteza , Recuperação e Remediação Ambiental/tendências
9.
Nature ; 633(8029): 417-425, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39198650

RESUMO

Severe defects in human IFNγ immunity predispose individuals to both Bacillus Calmette-Guérin disease and tuberculosis, whereas milder defects predispose only to tuberculosis1. Here we report two adults with recurrent pulmonary tuberculosis who are homozygous for a private loss-of-function TNF variant. Neither has any other clinical phenotype and both mount normal clinical and biological inflammatory responses. Their leukocytes, including monocytes and monocyte-derived macrophages (MDMs) do not produce TNF, even after stimulation with IFNγ. Blood leukocyte subset development is normal in these patients. However, an impairment in the respiratory burst was observed in granulocyte-macrophage colony-stimulating factor (GM-CSF)-matured MDMs and alveolar macrophage-like (AML) cells2 from both patients with TNF deficiency, TNF- or TNFR1-deficient induced pluripotent stem (iPS)-cell-derived GM-CSF-matured macrophages, and healthy control MDMs and AML cells differentiated with TNF blockers in vitro, and in lung macrophages treated with TNF blockers ex vivo. The stimulation of TNF-deficient iPS-cell-derived macrophages with TNF rescued the respiratory burst. These findings contrast with those for patients with inherited complete deficiency of the respiratory burst across all phagocytes, who are prone to multiple infections, including both Bacillus Calmette-Guérin disease and tuberculosis3. Human TNF is required for respiratory-burst-dependent immunity to Mycobacterium tuberculosis in macrophages but is surprisingly redundant otherwise, including for inflammation and immunity to weakly virulent mycobacteria and many other infectious agents.


Assuntos
Macrófagos , Tuberculose Pulmonar , Fatores de Necrose Tumoral , Adulto , Feminino , Humanos , Masculino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Homozigoto , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/imunologia , Células-Tronco Pluripotentes Induzidas/citologia , Inflamação/imunologia , Interferon gama/imunologia , Mutação com Perda de Função , Pulmão/citologia , Pulmão/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Macrófagos Alveolares/citologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/patologia , Mycobacterium tuberculosis/imunologia , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/deficiência , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Explosão Respiratória , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/genética , Inibidores do Fator de Necrose Tumoral/farmacologia , Fatores de Necrose Tumoral/deficiência , Fatores de Necrose Tumoral/genética , Adolescente , Adulto Jovem
10.
Nature ; 631(8022): 835-842, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987593

RESUMO

Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions1,2. To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores3. The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms4,5.


Assuntos
Microbiologia do Ar , Biodiversidade , DNA Fúngico , Fungos , Estações do Ano , Análise Espaço-Temporal , DNA Fúngico/análise , DNA Fúngico/genética , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Micorrizas/genética , Micorrizas/classificação , Micorrizas/isolamento & purificação , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/isolamento & purificação , Temperatura , Clima Tropical , Mapeamento Geográfico
11.
Nature ; 615(7952): 436-442, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922608

RESUMO

The globally important carbon sink of intact, old-growth tropical humid forests is declining because of climate change, deforestation and degradation from fire and logging1-3. Recovering tropical secondary and degraded forests now cover about 10% of the tropical forest area4, but how much carbon they accumulate remains uncertain. Here we quantify the aboveground carbon (AGC) sink of recovering forests across three main continuous tropical humid regions: the Amazon, Borneo and Central Africa5,6. On the basis of satellite data products4,7, our analysis encompasses the heterogeneous spatial and temporal patterns of growth in degraded and secondary forests, influenced by key environmental and anthropogenic drivers. In the first 20 years of recovery, regrowth rates in Borneo were up to 45% and 58% higher than in Central Africa and the Amazon, respectively. This is due to variables such as temperature, water deficit and disturbance regimes. We find that regrowing degraded and secondary forests accumulated 107 Tg C year-1 (90-130 Tg C year-1) between 1984 and 2018, counterbalancing 26% (21-34%) of carbon emissions from humid tropical forest loss during the same period. Protecting old-growth forests is therefore a priority. Furthermore, we estimate that conserving recovering degraded and secondary forests can have a feasible future carbon sink potential of 53 Tg C year-1 (44-62 Tg C year-1) across the main tropical regions studied.


Assuntos
Sequestro de Carbono , Carbono , Conservação dos Recursos Naturais , Florestas , Umidade , Árvores , Clima Tropical , Carbono/metabolismo , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Árvores/metabolismo , Agricultura Florestal/estatística & dados numéricos , Imagens de Satélites , Temperatura , Floresta Úmida , Bornéu , África Central , Brasil
12.
Nature ; 618(7967): 967-973, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37380694

RESUMO

Observational evidence shows the ubiquitous presence of ocean-emitted short-lived halogens in the global atmosphere1-3. Natural emissions of these chemical compounds have been anthropogenically amplified since pre-industrial times4-6, while, in addition, anthropogenic short-lived halocarbons are currently being emitted to the atmosphere7,8. Despite their widespread distribution in the atmosphere, the combined impact of these species on Earth's radiative balance remains unknown. Here we show that short-lived halogens exert a substantial indirect cooling effect at present (-0.13 ± 0.03 watts per square metre) that arises from halogen-mediated radiative perturbations of ozone (-0.24 ± 0.02 watts per square metre), compensated by those from methane (+0.09 ± 0.01 watts per square metre), aerosols (+0.03 ± 0.01 watts per square metre) and stratospheric water vapour (+0.011 ± 0.001 watts per square metre). Importantly, this substantial cooling effect has increased since 1750 by -0.05 ± 0.03 watts per square metre (61 per cent), driven by the anthropogenic amplification of natural halogen emissions, and is projected to change further (18-31 per cent by 2100) depending on climate warming projections and socioeconomic development. We conclude that the indirect radiative effect due to short-lived halogens should now be incorporated into climate models to provide a more realistic natural baseline of Earth's climate system.


Assuntos
Atmosfera , Mudança Climática , Modelos Climáticos , Clima , Temperatura Baixa , Halogênios , Atmosfera/análise , Atmosfera/química , Halogênios/análise , Hidrocarbonetos Halogenados , Oceanos e Mares , Água do Mar/análise , Água do Mar/química , Mudança Climática/estatística & dados numéricos , Atividades Humanas
13.
Nature ; 622(7984): 775-783, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37821706

RESUMO

Latin America continues to be severely underrepresented in genomics research, and fine-scale genetic histories and complex trait architectures remain hidden owing to insufficient data1. To fill this gap, the Mexican Biobank project genotyped 6,057 individuals from 898 rural and urban localities across all 32 states in Mexico at a resolution of 1.8 million genome-wide markers with linked complex trait and disease information creating a valuable nationwide genotype-phenotype database. Here, using ancestry deconvolution and inference of identity-by-descent segments, we inferred ancestral population sizes across Mesoamerican regions over time, unravelling Indigenous, colonial and postcolonial demographic dynamics2-6. We observed variation in runs of homozygosity among genomic regions with different ancestries reflecting distinct demographic histories and, in turn, different distributions of rare deleterious variants. We conducted genome-wide association studies (GWAS) for 22 complex traits and found that several traits are better predicted using the Mexican Biobank GWAS compared to the UK Biobank GWAS7,8. We identified genetic and environmental factors associating with trait variation, such as the length of the genome in runs of homozygosity as a predictor for body mass index, triglycerides, glucose and height. This study provides insights into the genetic histories of individuals in Mexico and dissects their complex trait architectures, both crucial for making precision and preventive medicine initiatives accessible worldwide.


Assuntos
Bancos de Espécimes Biológicos , Genética Médica , Genoma Humano , Genômica , Hispânico ou Latino , Humanos , Glicemia/genética , Glicemia/metabolismo , Estatura/genética , Índice de Massa Corporal , Interação Gene-Ambiente , Marcadores Genéticos/genética , Estudo de Associação Genômica Ampla , Hispânico ou Latino/classificação , Hispânico ou Latino/genética , Homozigoto , México , Fenótipo , Triglicerídeos/sangue , Triglicerídeos/genética , Reino Unido , Genoma Humano/genética
14.
Nature ; 617(7959): 111-117, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37100901

RESUMO

Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, [Formula: see text]50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3-5, little is known about how these vary across Earth's largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters [Formula: see text]50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both [Formula: see text]50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth-mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink.


Assuntos
Carbono , Florestas , Árvores , Clima Tropical , Biomassa , Carbono/metabolismo , Secas , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Xilema/metabolismo , Chuva , Mudança Climática , Sequestro de Carbono , Estresse Fisiológico , Desidratação
15.
Cell ; 155(2): 308-20, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24120132

RESUMO

Sensory dendrites depend on cues from their environment to pattern their growth and direct them toward their correct target tissues. Yet, little is known about dendrite-substrate interactions during dendrite morphogenesis. Here, we describe MNR-1/menorin, which is part of the conserved Fam151 family of proteins and is expressed in the skin to control the elaboration of "menorah"-like dendrites of mechanosensory neurons in Caenorhabditis elegans. We provide biochemical and genetic evidence that MNR-1 acts as a contact-dependent or short-range cue in concert with the neural cell adhesion molecule SAX-7/L1CAM in the skin and through the neuronal leucine-rich repeat transmembrane receptor DMA-1 on sensory dendrites. Our data describe an unknown pathway that provides spatial information from the skin substrate to pattern sensory dendrite development nonautonomously.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Dendritos/metabolismo , Proteínas de Membrana/metabolismo , Neurônios/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Caenorhabditis elegans/genética , Clonagem Molecular , Técnicas de Silenciamento de Genes , Proteínas de Membrana/genética , Dados de Sequência Molecular , Alinhamento de Sequência
16.
Nature ; 602(7897): 518-522, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35140400

RESUMO

The epidermal growth factor receptor (EGFR) is frequently mutated in human cancer1,2, and is an important therapeutic target. EGFR inhibitors have been successful in lung cancer, where mutations in the intracellular tyrosine kinase domain activate the receptor1, but not in glioblastoma multiforme (GBM)3, where mutations occur exclusively in the extracellular region. Here we show that common extracellular GBM mutations prevent EGFR from discriminating between its activating ligands4. Different growth factor ligands stabilize distinct EGFR dimer structures5 that signal with different kinetics to specify or bias outcome5,6. EGF itself induces strong symmetric dimers that signal transiently to promote proliferation. Epiregulin (EREG) induces much weaker asymmetric dimers that drive sustained signalling and differentiation5. GBM mutations reduce the ability of EGFR to distinguish EREG from EGF in cellular assays, and allow EGFR to form strong (EGF-like) dimers in response to EREG and other low-affinity ligands. Using X-ray crystallography, we further show that the R84K GBM mutation symmetrizes EREG-driven extracellular dimers so that they resemble dimers normally seen with EGF. By contrast, a second GBM mutation, A265V, remodels key dimerization contacts to strengthen asymmetric EREG-driven dimers. Our results argue for an important role of altered ligand discrimination by EGFR in GBM, with potential implications for therapeutic targeting.


Assuntos
Glioblastoma , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Ligantes , Mutação
17.
Nature ; 610(7933): 693-698, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36224389

RESUMO

Soils are the foundation of all terrestrial ecosystems1. However, unlike for plants and animals, a global assessment of hotspots for soil nature conservation is still lacking2. This hampers our ability to establish nature conservation priorities for the multiple dimensions that support the soil system: from soil biodiversity to ecosystem services. Here, to identify global hotspots for soil nature conservation, we performed a global field survey that includes observations of biodiversity (archaea, bacteria, fungi, protists and invertebrates) and functions (critical for six ecosystem services) in 615 composite samples of topsoil from a standardized survey in all continents. We found that each of the different ecological dimensions of soils-that is, species richness (alpha diversity, measured as amplicon sequence variants), community dissimilarity and ecosystem services-peaked in contrasting regions of the planet, and were associated with different environmental factors. Temperate ecosystems showed the highest species richness, whereas community dissimilarity peaked in the tropics, and colder high-latitudinal ecosystems were identified as hotspots of ecosystem services. These findings highlight the complexities that are involved in simultaneously protecting multiple ecological dimensions of soil. We further show that most of these hotspots are not adequately covered by protected areas (more than 70%), and are vulnerable in the context of several scenarios of global change. Our global estimation of priorities for soil nature conservation highlights the importance of accounting for the multidimensionality of soil biodiversity and ecosystem services to conserve soils for future generations.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Mapeamento Geográfico , Microbiologia do Solo , Solo , Animais , Conservação dos Recursos Naturais/métodos , Solo/parasitologia , Invertebrados , Archaea
18.
Am J Hum Genet ; 111(5): 841-862, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38593811

RESUMO

RNA sequencing (RNA-seq) has recently been used in translational research settings to facilitate diagnoses of Mendelian disorders. A significant obstacle for clinical laboratories in adopting RNA-seq is the low or absent expression of a significant number of disease-associated genes/transcripts in clinically accessible samples. As this is especially problematic in neurological diseases, we developed a clinical diagnostic approach that enhanced the detection and evaluation of tissue-specific genes/transcripts through fibroblast-to-neuron cell transdifferentiation. The approach is designed specifically to suit clinical implementation, emphasizing simplicity, cost effectiveness, turnaround time, and reproducibility. For clinical validation, we generated induced neurons (iNeurons) from 71 individuals with primary neurological phenotypes recruited to the Undiagnosed Diseases Network. The overall diagnostic yield was 25.4%. Over a quarter of the diagnostic findings benefited from transdifferentiation and could not be achieved by fibroblast RNA-seq alone. This iNeuron transcriptomic approach can be effectively integrated into diagnostic whole-transcriptome evaluation of individuals with genetic disorders.


Assuntos
Transdiferenciação Celular , Fibroblastos , Neurônios , Análise de Sequência de RNA , Humanos , Transdiferenciação Celular/genética , Fibroblastos/metabolismo , Fibroblastos/citologia , Análise de Sequência de RNA/métodos , Neurônios/metabolismo , Neurônios/citologia , Transcriptoma , Reprodutibilidade dos Testes , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/diagnóstico , RNA-Seq/métodos , Feminino , Masculino
19.
N Engl J Med ; 391(16): 1511-1518, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39442041

RESUMO

CHASERR encodes a human long noncoding RNA (lncRNA) adjacent to CHD2, a coding gene in which de novo loss-of-function variants cause developmental and epileptic encephalopathy. Here, we report our findings in three unrelated children with a syndromic, early-onset neurodevelopmental disorder, each of whom had a de novo deletion in the CHASERR locus. The children had severe encephalopathy, shared facial dysmorphisms, cortical atrophy, and cerebral hypomyelination - a phenotype that is distinct from the phenotypes of patients with CHD2 haploinsufficiency. We found that the CHASERR deletion results in increased CHD2 protein abundance in patient-derived cell lines and increased expression of the CHD2 transcript in cis. These findings indicate that CHD2 has bidirectional dosage sensitivity in human disease, and we recommend that other lncRNA-encoding genes be evaluated, particularly those upstream of genes associated with mendelian disorders. (Funded by the National Human Genome Research Institute and others.).


Assuntos
Transtornos do Neurodesenvolvimento , RNA Longo não Codificante , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Deleção de Genes , Haploinsuficiência , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia , Fenótipo , RNA Longo não Codificante/genética , Deleção de Sequência
20.
N Engl J Med ; 390(19): 1745-1755, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38749032

RESUMO

BACKGROUND: Patients with acute intracerebral hemorrhage who are receiving factor Xa inhibitors have a risk of hematoma expansion. The effect of andexanet alfa, an agent that reverses the effects of factor Xa inhibitors, on hematoma volume expansion has not been well studied. METHODS: We randomly assigned, in a 1:1 ratio, patients who had taken factor Xa inhibitors within 15 hours before having an acute intracerebral hemorrhage to receive andexanet or usual care. The primary end point was hemostatic efficacy, defined by expansion of the hematoma volume by 35% or less at 12 hours after baseline, an increase in the score on the National Institutes of Health Stroke Scale of less than 7 points (scores range from 0 to 42, with higher scores indicating worse neurologic deficit) at 12 hours, and no receipt of rescue therapy between 3 hours and 12 hours. Safety end points were thrombotic events and death. RESULTS: A total of 263 patients were assigned to receive andexanet, and 267 to receive usual care. Efficacy was assessed in an interim analysis that included 452 patients, and safety was analyzed in all 530 enrolled patients. Atrial fibrillation was the most common indication for factor Xa inhibitors. Of the patients receiving usual care, 85.5% received prothrombin complex concentrate. Hemostatic efficacy was achieved in 150 of 224 patients (67.0%) receiving andexanet and in 121 of 228 (53.1%) receiving usual care (adjusted difference, 13.4 percentage points; 95% confidence interval [CI], 4.6 to 22.2; P = 0.003). The median reduction from baseline to the 1-to-2-hour nadir in anti-factor Xa activity was 94.5% with andexanet and 26.9% with usual care (P<0.001). Thrombotic events occurred in 27 of 263 patients (10.3%) receiving andexanet and in 15 of 267 (5.6%) receiving usual care (difference, 4.6 percentage points; 95% CI, 0.1 to 9.2; P = 0.048); ischemic stroke occurred in 17 patients (6.5%) and 4 patients (1.5%), respectively. There were no appreciable differences between the groups in the score on the modified Rankin scale or in death within 30 days. CONCLUSIONS: Among patients with intracerebral hemorrhage who were receiving factor Xa inhibitors, andexanet resulted in better control of hematoma expansion than usual care but was associated with thrombotic events, including ischemic stroke. (Funded by Alexion AstraZeneca Rare Disease and others; ANNEXA-I ClinicalTrials.gov number, NCT03661528.).


Assuntos
Hemorragia Cerebral , Inibidores do Fator Xa , Fator Xa , Hematoma , Proteínas Recombinantes , Humanos , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Idoso , Masculino , Feminino , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/induzido quimicamente , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Proteínas Recombinantes/efeitos adversos , Fator Xa/uso terapêutico , Fator Xa/efeitos adversos , Hematoma/induzido quimicamente , Hematoma/tratamento farmacológico , Idoso de 80 Anos ou mais , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Doença Aguda
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