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1.
Cell ; 185(8): 1356-1372.e26, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35395179

RESUMO

Tumor-resident intracellular microbiota is an emerging tumor component that has been documented for a variety of cancer types with unclear biological functions. Here, we explored the functional significance of these intratumor bacteria, primarily using a murine spontaneous breast-tumor model MMTV-PyMT. We found that depletion of intratumor bacteria significantly reduced lung metastasis without affecting primary tumor growth. During metastatic colonization, intratumor bacteria carried by circulating tumor cells promoted host-cell survival by enhancing resistance to fluid shear stress by reorganizing actin cytoskeleton. We further showed that intratumor administration of selected bacteria strains isolated from tumor-resident microbiota promoted metastasis in two murine tumor models with significantly different levels of metastasis potential. Our findings suggest that tumor-resident microbiota, albeit at low biomass, play an important role in promoting cancer metastasis, intervention of which might therefore be worth exploring for advancing oncology care.


Assuntos
Neoplasias da Mama , Microbiota , Metástase Neoplásica , Animais , Neoplasias da Mama/microbiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Células Neoplásicas Circulantes/patologia
2.
Cell ; 185(1): 95-112.e18, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34995520

RESUMO

Fingerprints are of long-standing practical and cultural interest, but little is known about the mechanisms that underlie their variation. Using genome-wide scans in Han Chinese cohorts, we identified 18 loci associated with fingerprint type across the digits, including a genetic basis for the long-recognized "pattern-block" correlations among the middle three digits. In particular, we identified a variant near EVI1 that alters regulatory activity and established a role for EVI1 in dermatoglyph patterning in mice. Dynamic EVI1 expression during human development supports its role in shaping the limbs and digits, rather than influencing skin patterning directly. Trans-ethnic meta-analysis identified 43 fingerprint-associated loci, with nearby genes being strongly enriched for general limb development pathways. We also found that fingerprint patterns were genetically correlated with hand proportions. Taken together, these findings support the key role of limb development genes in influencing the outcome of fingerprint patterning.


Assuntos
Dermatoglifia , Dedos/crescimento & desenvolvimento , Organogênese/genética , Polimorfismo de Nucleotídeo Único , Dedos do Pé/crescimento & desenvolvimento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Povo Asiático/genética , Padronização Corporal/genética , Criança , Estudos de Coortes , Feminino , Membro Anterior/crescimento & desenvolvimento , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Proteína do Locus do Complexo MDS1 e EVI1/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
3.
Cell ; 179(2): 498-513.e22, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31585084

RESUMO

Neuromodulators bind to pre- and postsynaptic G protein-coupled receptors (GPCRs), are able to quickly change intracellular cyclic AMP (cAMP) and Ca2+ levels, and are thought to play important roles in neuropsychiatric and neurodegenerative diseases. Here, we discovered in human neurons an unanticipated presynaptic mechanism that acutely changes synaptic ultrastructure and regulates synaptic communication. Activation of neuromodulator receptors bidirectionally controlled synaptic vesicle numbers within nerve terminals. This control correlated with changes in the levels of cAMP-dependent protein kinase A-mediated phosphorylation of synapsin-1. Using a conditional deletion approach, we reveal that the neuromodulator-induced control of synaptic vesicle numbers was largely dependent on synapsin-1. We propose a mechanism whereby non-phosphorylated synapsin-1 "latches" synaptic vesicles to presynaptic clusters at the active zone. cAMP-dependent phosphorylation of synapsin-1 then removes the vesicles. cAMP-independent dephosphorylation of synapsin-1 in turn recruits vesicles. Synapsin-1 thereby bidirectionally regulates synaptic vesicle numbers and modifies presynaptic neurotransmitter release as an effector of neuromodulator signaling in human neurons.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Terminações Pré-Sinápticas/metabolismo , Sinapsinas/metabolismo , Transmissão Sináptica , Vesículas Sinápticas/metabolismo , Animais , Células Cultivadas , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neurotransmissores/metabolismo , Receptores de Neurotransmissores/metabolismo , Transdução de Sinais
4.
Cell ; 176(5): 1113-1127.e16, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30712867

RESUMO

Activating mutations in NRAS account for 20%-30% of melanoma, but despite decades of research and in contrast to BRAF, no effective anti-NRAS therapies have been forthcoming. Here, we identify a previously uncharacterized serine/threonine kinase STK19 as a novel NRAS activator. STK19 phosphorylates NRAS to enhance its binding to its downstream effectors and promotes oncogenic NRAS-mediated melanocyte malignant transformation. A recurrent D89N substitution in STK19 whose alterations were identified in 25% of human melanomas represents a gain-of-function mutation that interacts better with NRAS to enhance melanocyte transformation. STK19D89N knockin leads to skin hyperpigmentation and promotes NRASQ61R-driven melanomagenesis in vivo. Finally, we developed ZT-12-037-01 (1a) as a specific STK19-targeted inhibitor and showed that it effectively blocks oncogenic NRAS-driven melanocyte malignant transformation and melanoma growth in vitro and in vivo. Together, our findings provide a new and viable therapeutic strategy for melanomas harboring NRAS mutations.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Melanoma/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Feminino , Células HEK293 , Humanos , Melanócitos/metabolismo , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Mutação , Fosforilação , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais , Neoplasias Cutâneas/genética
5.
Cell ; 174(6): 1571-1585.e11, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30193114

RESUMO

Metabolic diseases are often characterized by circadian misalignment in different tissues, yet how altered coordination and communication among tissue clocks relate to specific pathogenic mechanisms remains largely unknown. Applying an integrated systems biology approach, we performed 24-hr metabolomics profiling of eight mouse tissues simultaneously. We present a temporal and spatial atlas of circadian metabolism in the context of systemic energy balance and under chronic nutrient stress (high-fat diet [HFD]). Comparative analysis reveals how the repertoires of tissue metabolism are linked and gated to specific temporal windows and how this highly specialized communication and coherence among tissue clocks is rewired by nutrient challenge. Overall, we illustrate how dynamic metabolic relationships can be reconstructed across time and space and how integration of circadian metabolomics data from multiple tissues can improve our understanding of health and disease.


Assuntos
Relógios Circadianos/fisiologia , Metaboloma , Animais , Dieta Hiperlipídica , Metabolismo Energético , Fígado/metabolismo , Masculino , Redes e Vias Metabólicas , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Córtex Pré-Frontal/metabolismo , Núcleo Supraquiasmático/metabolismo , Proteína Desacopladora 1/metabolismo
6.
Mol Cell ; 84(12): 2304-2319.e8, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38838666

RESUMO

Circular RNAs (circRNAs) are upregulated during neurogenesis. Where and how circRNAs are localized and what roles they play during this process have remained elusive. Comparing the nuclear and cytoplasmic circRNAs between H9 cells and H9-derived forebrain (FB) neurons, we identify that a subset of adenosine (A)-rich circRNAs are restricted in H9 nuclei but exported to cytosols upon differentiation. Such a subcellular relocation of circRNAs is modulated by the poly(A)-binding protein PABPC1. In the H9 nucleus, newly produced (A)-rich circRNAs are bound by PABPC1 and trapped by the nuclear basket protein TPR to prevent their export. Modulating (A)-rich motifs in circRNAs alters their subcellular localization, and introducing (A)-rich circRNAs in H9 cytosols results in mRNA translation suppression. Moreover, decreased nuclear PABPC1 upon neuronal differentiation enables the export of (A)-rich circRNAs, including circRTN4(2,3), which is required for neurite outgrowth. These findings uncover subcellular localization features of circRNAs, linking their processing and function during neurogenesis.


Assuntos
Transporte Ativo do Núcleo Celular , Adenosina , Núcleo Celular , Neurogênese , Neurônios , Proteína I de Ligação a Poli(A) , RNA Circular , RNA , RNA Circular/metabolismo , RNA Circular/genética , Neurônios/metabolismo , Adenosina/metabolismo , Núcleo Celular/metabolismo , Humanos , Proteína I de Ligação a Poli(A)/metabolismo , Proteína I de Ligação a Poli(A)/genética , Animais , RNA/metabolismo , RNA/genética , Linhagem Celular , Diferenciação Celular , Citoplasma/metabolismo , Prosencéfalo/metabolismo
7.
Mol Cell ; 84(8): 1422-1441.e14, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38521067

RESUMO

The topological state of chromosomes determines their mechanical properties, dynamics, and function. Recent work indicated that interphase chromosomes are largely free of entanglements. Here, we use Hi-C, polymer simulations, and multi-contact 3C and find that, by contrast, mitotic chromosomes are self-entangled. We explore how a mitotic self-entangled state is converted into an unentangled interphase state during mitotic exit. Most mitotic entanglements are removed during anaphase/telophase, with remaining ones removed during early G1, in a topoisomerase-II-dependent process. Polymer models suggest a two-stage disentanglement pathway: first, decondensation of mitotic chromosomes with remaining condensin loops produces entropic forces that bias topoisomerase II activity toward decatenation. At the second stage, the loops are released, and the formation of new entanglements is prevented by lower topoisomerase II activity, allowing the establishment of unentangled and territorial G1 chromosomes. When mitotic entanglements are not removed in experiments and models, a normal interphase state cannot be acquired.


Assuntos
Cromossomos , DNA Topoisomerases Tipo II , DNA Topoisomerases Tipo II/genética , Cromossomos/genética , Mitose/genética , Interfase/genética , Polímeros
8.
Cell ; 165(4): 896-909, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27153497

RESUMO

The circadian clock controls metabolic and physiological processes through finely tuned molecular mechanisms. The clock is remarkably plastic and adapts to exogenous "zeitgebers," such as light and nutrition. How a pathological condition in a given tissue influences systemic circadian homeostasis in other tissues remains an unanswered question of conceptual and biomedical importance. Here, we show that lung adenocarcinoma operates as an endogenous reorganizer of circadian metabolism. High-throughput transcriptomics and metabolomics revealed unique signatures of transcripts and metabolites cycling exclusively in livers of tumor-bearing mice. Remarkably, lung cancer has no effect on the core clock but rather reprograms hepatic metabolism through altered pro-inflammatory response via the STAT3-Socs3 pathway. This results in disruption of AKT, AMPK, and SREBP signaling, leading to altered insulin, glucose, and lipid metabolism. Thus, lung adenocarcinoma functions as a potent endogenous circadian organizer (ECO), which rewires the pathophysiological dimension of a distal tissue such as the liver. PAPERCLIP.


Assuntos
Adenocarcinoma/fisiopatologia , Relógios Circadianos , Fígado/fisiopatologia , Neoplasias Pulmonares/fisiopatologia , Adenocarcinoma de Pulmão , Animais , Citocinas/genética , Glucose/metabolismo , Homeostase , Insulina/metabolismo , Camundongos , Transdução de Sinais
9.
Nature ; 630(8015): 141-148, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38778097

RESUMO

Fentanyl is a powerful painkiller that elicits euphoria and positive reinforcement1. Fentanyl also leads to dependence, defined by the aversive withdrawal syndrome, which fuels negative reinforcement2,3 (that is, individuals retake the drug to avoid withdrawal). Positive and negative reinforcement maintain opioid consumption, which leads to addiction in one-fourth of users, the largest fraction for all addictive drugs4. Among the opioid receptors, µ-opioid receptors have a key role5, yet the induction loci of circuit adaptations that eventually lead to addiction remain unknown. Here we injected mice with fentanyl to acutely inhibit γ-aminobutyric acid-expressing neurons in the ventral tegmental area (VTA), causing disinhibition of dopamine neurons, which eventually increased dopamine in the nucleus accumbens. Knockdown of µ-opioid receptors in VTA abolished dopamine transients and positive reinforcement, but withdrawal remained unchanged. We identified neurons expressing µ-opioid receptors in the central amygdala (CeA) whose activity was enhanced during withdrawal. Knockdown of µ-opioid receptors in CeA eliminated aversive symptoms, suggesting that they mediate negative reinforcement. Thus, optogenetic stimulation caused place aversion, and mice readily learned to press a lever to pause optogenetic stimulation of CeA neurons that express µ-opioid receptors. Our study parses the neuronal populations that trigger positive and negative reinforcement in VTA and CeA, respectively. We lay out the circuit organization to develop interventions for reducing fentanyl addiction and facilitating rehabilitation.


Assuntos
Fentanila , Receptores Opioides mu , Reforço Psicológico , Animais , Feminino , Masculino , Camundongos , Analgésicos Opioides/farmacologia , Analgésicos Opioides/administração & dosagem , Núcleo Central da Amígdala/citologia , Núcleo Central da Amígdala/efeitos dos fármacos , Núcleo Central da Amígdala/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Fentanila/farmacologia , Camundongos Endogâmicos C57BL , Núcleo Accumbens/citologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Transtornos Relacionados ao Uso de Opioides/metabolismo , Transtornos Relacionados ao Uso de Opioides/patologia , Optogenética , Receptores Opioides mu/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Síndrome de Abstinência a Substâncias/patologia , Área Tegmentar Ventral/citologia , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo
10.
Nature ; 627(8003): 295-300, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38383784

RESUMO

The ability to detect single photons has led to the advancement of numerous research fields1-11. Although various types of single-photon detector have been developed12, because of two main factors-that is, (1) the need for operating at cryogenic temperature13,14 and (2) the incompatibility with complementary metal-oxide-semiconductor (CMOS) fabrication processes15,16-so far, to our knowledge, only Si-based single-photon avalanche diode (SPAD)17,18 has gained mainstream success and has been used in consumer electronics. With the growing demand to shift the operation wavelength from near-infrared to short-wavelength infrared (SWIR) for better safety and performance19-21, an alternative solution is required because Si has negligible optical absorption for wavelengths beyond 1 µm. Here we report a CMOS-compatible, high-performing germanium-silicon SPAD operated at room temperature, featuring a noise-equivalent power improvement over the previous Ge-based SPADs22-28 by 2-3.5 orders of magnitude. Key parameters such as dark count rate, single-photon detection probability at 1,310 nm, timing jitter, after-pulsing characteristic time and after-pulsing probability are, respectively, measured as 19 kHz µm-2, 12%, 188 ps, ~90 ns and <1%, with a low breakdown voltage of 10.26 V and a small excess bias of 0.75 V. Three-dimensional point-cloud images are captured with direct time-of-flight technique as proof of concept. This work paves the way towards using single-photon-sensitive SWIR sensors, imagers and photonic integrated circuits in everyday life.

11.
Nature ; 630(8015): 206-213, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38778111

RESUMO

Targeted radionuclide therapy, in which radiopharmaceuticals deliver potent radionuclides to tumours for localized irradiation, has addressed unmet clinical needs and improved outcomes for patients with cancer1-4. A therapeutic radiopharmaceutical must achieve both sustainable tumour targeting and fast clearance from healthy tissue, which remains a major challenge5,6. A targeted ligation strategy that selectively fixes the radiopharmaceutical to the target protein in the tumour would be an ideal solution. Here we installed a sulfur (VI) fluoride exchange (SuFEx) chemistry-based linker on radiopharmaceuticals to prevent excessively fast tumour clearance. When the engineered radiopharmaceutical binds to the tumour-specific protein, the system undergoes a binding-to-ligation transition and readily conjugates to the tyrosine residues through the 'click' SuFEx reaction. The application of this strategy to a fibroblast activation protein (FAP) inhibitor (FAPI) triggered more than 80% covalent binding to the protein and almost no dissociation for six days. In mice, SuFEx-engineered FAPI showed 257% greater tumour uptake than did the original FAPI, and increased tumour retention by 13-fold. The uptake in healthy tissues was rapidly cleared. In a pilot imaging study, this strategy identified more tumour lesions in patients with cancer than did other methods. SuFEx-engineered FAPI also successfully achieved targeted ß- and α-radionuclide therapy, causing nearly complete tumour regression in mice. Another SuFEx-engineered radioligand that targets prostate-specific membrane antigen (PSMA) also showed enhanced therapeutic efficacy. Considering the broad scope of proteins that can potentially be ligated to SuFEx warheads, it might be possible to adapt this strategy to other cancer targets.


Assuntos
Terapia de Alvo Molecular , Neoplasias da Próstata , Radioisótopos , Compostos Radiofarmacêuticos , Animais , Humanos , Masculino , Camundongos , Antígenos de Superfície/química , Antígenos de Superfície/metabolismo , Linhagem Celular Tumoral , Fluoretos/química , Fluoretos/metabolismo , Glutamato Carboxipeptidase II/química , Glutamato Carboxipeptidase II/metabolismo , Ligantes , Proteínas de Membrana/metabolismo , Proteínas de Membrana/química , Terapia de Alvo Molecular/métodos , Projetos Piloto , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/radioterapia , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/uso terapêutico , Compostos Radiofarmacêuticos/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Compostos de Enxofre/química , Compostos de Enxofre/metabolismo , Tirosina/metabolismo , Tirosina/química , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Nature ; 629(8013): 901-909, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658756

RESUMO

The liver is the main gateway from the gut, and the unidirectional sinusoidal flow from portal to central veins constitutes heterogenous zones, including the periportal vein (PV) and the pericentral vein zones1-5. However, functional differences in the immune system in each zone remain poorly understood. Here intravital imaging revealed that inflammatory responses are suppressed in PV zones. Zone-specific single-cell transcriptomics detected a subset of immunosuppressive macrophages enriched in PV zones that express high levels of interleukin-10 and Marco, a scavenger receptor that sequesters pro-inflammatory pathogen-associated molecular patterns and damage-associated molecular patterns, and consequently suppress immune responses. Induction of Marco+ immunosuppressive macrophages depended on gut microbiota. In particular, a specific bacterial family, Odoribacteraceae, was identified to induce this macrophage subset through its postbiotic isoallolithocholic acid. Intestinal barrier leakage resulted in inflammation in PV zones, which was markedly augmented in Marco-deficient conditions. Chronic liver inflammatory diseases such as primary sclerosing cholangitis (PSC) and non-alcoholic steatohepatitis (NASH) showed decreased numbers of Marco+ macrophages. Functional ablation of Marco+ macrophages led to PSC-like inflammatory phenotypes related to colitis and exacerbated steatosis in NASH in animal experimental models. Collectively, commensal bacteria induce Marco+ immunosuppressive macrophages, which consequently limit excessive inflammation at the gateway of the liver. Failure of this self-limiting system promotes hepatic inflammatory disorders such as PSC and NASH.


Assuntos
Colangite Esclerosante , Microbioma Gastrointestinal , Inflamação , Fígado , Macrófagos , Hepatopatia Gordurosa não Alcoólica , Simbiose , Animais , Feminino , Humanos , Masculino , Camundongos , Bacteroidetes/metabolismo , Colangite Esclerosante/imunologia , Colangite Esclerosante/microbiologia , Colangite Esclerosante/patologia , Microbioma Gastrointestinal/imunologia , Microbioma Gastrointestinal/fisiologia , Perfilação da Expressão Gênica , Inflamação/imunologia , Inflamação/microbiologia , Inflamação/patologia , Interleucina-10/imunologia , Interleucina-10/metabolismo , Fígado/imunologia , Fígado/patologia , Fígado/microbiologia , Macrófagos/citologia , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Veia Porta , Receptores Imunológicos/deficiência , Receptores Imunológicos/metabolismo , Análise de Célula Única , Simbiose/imunologia
13.
Cell ; 155(3): 594-605, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24243017

RESUMO

Nuclear export of unspliced and singly spliced viral mRNA is a critical step in the HIV life cycle. The structural basis by which the virus selects its own mRNA among more abundant host cellular RNAs for export has been a mystery for more than 25 years. Here, we describe an unusual topological structure that the virus uses to recognize its own mRNA. The viral Rev response element (RRE) adopts an "A"-like structure in which the two legs constitute two tracks of binding sites for the viral Rev protein and position the two primary known Rev-binding sites ~55 Å apart, matching the distance between the two RNA-binding motifs in the Rev dimer. Both the legs of the "A" and the separation between them are required for optimal RRE function. This structure accounts for the specificity of Rev for the RRE and thus the specific recognition of the viral RNA.


Assuntos
Transporte Ativo do Núcleo Celular , HIV-1/química , RNA Mensageiro/química , RNA Viral/química , Produtos do Gene rev do Vírus da Imunodeficiência Humana/química , Sequência de Bases , Sítios de Ligação , Núcleo Celular/metabolismo , Células HEK293 , HIV-1/genética , Humanos , Dados de Sequência Molecular , Poro Nuclear/metabolismo , Conformação de Ácido Nucleico , Dobramento de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Espalhamento a Baixo Ângulo , Difração de Raios X , Produtos do Gene rev do Vírus da Imunodeficiência Humana/genética , Produtos do Gene rev do Vírus da Imunodeficiência Humana/metabolismo
14.
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
15.
Nat Immunol ; 16(12): 1263-73, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26479789

RESUMO

Deregulation of the TH17 subset of helper T cells is closely linked with immunological disorders and inflammatory diseases. However, the mechanism by which TH17 cells are regulated remains elusive. Here we found that the phosphatase DUSP2 (PAC1) negatively regulated the development of TH17 cells. DUSP2 was directly associated with the signal transducer and transcription activator STAT3 and attenuated its activity through dephosphorylation of STAT3 at Tyr705 and Ser727. DUSP2-deficient mice exhibited severe susceptibility to experimental colitis, with enhanced differentiation of TH17 cells and secretion of proinflammatory cytokines. In clinical patients with ulcerative colitis, DUSP2 was downregulated by DNA methylation and was not induced during T cell activation. Our data demonstrate that DUSP2 is a true STAT3 phosphatase that modulates the development of TH17 cells in the autoimmune response and inflammation.


Assuntos
Diferenciação Celular/imunologia , Fosfatase 2 de Especificidade Dupla/imunologia , Fator de Transcrição STAT3/imunologia , Células Th17/imunologia , Animais , Células Cultivadas , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Colite Ulcerativa/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Metilação de DNA/imunologia , Sulfato de Dextrana , Fosfatase 2 de Especificidade Dupla/deficiência , Fosfatase 2 de Especificidade Dupla/genética , Regulação da Expressão Gênica/imunologia , Células HEK293 , Humanos , Immunoblotting , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação/imunologia , Ligação Proteica/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/metabolismo , Células Th17/metabolismo , Tirosina/imunologia , Tirosina/metabolismo
16.
Plant Cell ; 36(5): 1755-1776, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38318972

RESUMO

The milestone of compound leaf development is the generation of separate leaflet primordia during the early stages, which involves two linked but distinct morphogenetic events: leaflet initiation and boundary establishment for leaflet separation. Although some progress in understanding the regulatory pathways for each event have been made, it is unclear how they are intrinsically coordinated. Here, we identify the PINNATE-LIKE PENTAFOLIATA2 (PINNA2) gene encoding a newly identified GRAS transcription factor in Medicago truncatula. PINNA2 transcripts are preferentially detected at organ boundaries. Its loss-of-function mutations convert trifoliate leaves into a pinnate pentafoliate pattern. PINNA2 directly binds to the promoter region of the LEAFY orthologue SINGLE LEAFLET1 (SGL1), which encodes a key positive regulator of leaflet initiation, and downregulates its expression. Further analysis revealed that PINNA2 synergizes with two other repressors of SGL1 expression, the BEL1-like homeodomain protein PINNA1 and the C2H2 zinc finger protein PALMATE-LIKE PENTAFOLIATA1 (PALM1), to precisely define the spatiotemporal expression of SGL1 in compound leaf primordia, thereby maintaining a proper pattern of leaflet initiation. Moreover, we showed that the enriched expression of PINNA2 at the leaflet-to-leaflet boundaries is positively regulated by the boundary-specific gene MtNAM, which is essential for leaflet boundary formation. Together, these results unveil a pivotal role of the boundary-expressed transcription factor PINNA2 in regulating leaflet initiation, providing molecular insights into the coordination of intricate developmental processes underlying compound leaf pattern formation.


Assuntos
Regulação da Expressão Gênica de Plantas , Medicago truncatula , Folhas de Planta , Medicago truncatula/genética , Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/metabolismo , Morfogênese/genética , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
17.
Nature ; 593(7859): 379-384, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34012086

RESUMO

Chemical reactions represent a class of quantum problems that challenge both the current theoretical understanding and computational capabilities1. Reactions that occur at ultralow temperatures provide an ideal testing ground for quantum chemistry and scattering theories, because they can be experimentally studied with unprecedented control2, yet display dynamics that are highly complex3. Here we report the full product state distribution for the reaction 2KRb → K2 + Rb2. Ultracold preparation of the reactants allows us complete control over their initial quantum degrees of freedom, whereas state-resolved, coincident detection of both products enables the probability of scattering into each of the 57 allowed rotational state-pairs to be measured. Our results show an overall agreement with a state-counting model based on statistical theory4-6, but also reveal several deviating state-pairs. In particular, we observe a strong suppression of population in the state-pair closest to the exoergicity limit as a result of the long-range potential inhibiting the escape of products. The completeness of our measurements provides a benchmark for quantum dynamics calculations beyond the current state of the art.

18.
Nature ; 600(7887): 75-80, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34853455

RESUMO

Nonlinear wave-matter interactions may give rise to solitons, phenomena that feature inherent stability in wave propagation and unusual spectral characteristics. Solitons have been created in a variety of physical systems and have had important roles in a broad range of applications, including communications, spectroscopy and metrology1-4. In recent years, the realization of dissipative Kerr optical solitons in microcavities has led to the generation of frequency combs in a chip-scale platform5-10. Within a cavity, photons can interact with mechanical modes. Cavity optomechanics has found applications for frequency conversion, such as microwave-to-optical or radio-frequency-to-optical11-13, of interest for communications and interfacing quantum systems operating at different frequencies. Here we report the observation of mechanical micro-solitons excited by optical fields in an optomechanical microresonator, expanding soliton generation in optical resonators to a different spectral window. The optical field circulating along the circumference of a whispering gallery mode resonator triggers a mechanical nonlinearity through optomechanical coupling, which in turn induces a time-varying periodic modulation on the propagating mechanical mode, leading to a tailored modal dispersion. Stable localized mechanical wave packets-mechanical solitons-can be realized when the mechanical loss is compensated by phonon gain and the optomechanical nonlinearity is balanced by the tailored modal dispersion. The realization of mechanical micro-solitons driven by light opens up new avenues for optomechanical technologies14 and may find applications in acoustic sensing, information processing, energy storage, communications and surface acoustic wave technology.

19.
Nature ; 600(7887): 54-58, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34666338

RESUMO

The Moon has a magmatic and thermal history that is distinct from that of the terrestrial planets1. Radioisotope dating of lunar samples suggests that most lunar basaltic magmatism ceased by around 2.9-2.8 billion years ago (Ga)2,3, although younger basalts between 3 Ga and 1 Ga have been suggested by crater-counting chronology, which has large uncertainties owing to the lack of returned samples for calibration4,5. Here we report a precise lead-lead age of 2,030 ± 4 million years ago for basalt clasts returned by the Chang'e-5 mission, and a 238U/204Pb ratio (µ value)6 of about 680 for a source that evolved through two stages of differentiation. This is the youngest crystallization age reported so far for lunar basalts by radiometric dating, extending the duration of lunar volcanism by approximately 800-900 million years. The µ value of the Chang'e-5 basalt mantle source is within the range of low-titanium and high-titanium basalts from Apollo sites (µ value of about 300-1,000), but notably lower than those of potassium, rare-earth elements and phosphorus (KREEP) and high-aluminium basalts7 (µ value of about 2,600-3,700), indicating that the Chang'e-5 basalts were produced by melting of a KREEP-poor source. This age provides a pivotal calibration point for crater-counting chronology in the inner Solar System and provides insight on the volcanic and thermal history of the Moon.

20.
Nature ; 595(7868): 521-525, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34290425

RESUMO

Whereas ferromagnets have been known and used for millennia, antiferromagnets were only discovered in the 1930s1. At large scale, because of the absence of global magnetization, antiferromagnets may seem to behave like any non-magnetic material. At the microscopic level, however, the opposite alignment of spins forms a rich internal structure. In topological antiferromagnets, this internal structure leads to the possibility that the property known as the Berry phase can acquire distinct spatial textures2,3. Here we study this possibility in an antiferromagnetic axion insulator-even-layered, two-dimensional MnBi2Te4-in which spatial degrees of freedom correspond to different layers. We observe a type of Hall effect-the layer Hall effect-in which electrons from the top and bottom layers spontaneously deflect in opposite directions. Specifically, under zero electric field, even-layered MnBi2Te4 shows no anomalous Hall effect. However, applying an electric field leads to the emergence of a large, layer-polarized anomalous Hall effect of about 0.5e2/h (where e is the electron charge and h is Planck's constant). This layer Hall effect uncovers an unusual layer-locked Berry curvature, which serves to characterize the axion insulator state. Moreover, we find that the layer-locked Berry curvature can be manipulated by the axion field formed from the dot product of the electric and magnetic field vectors. Our results offer new pathways to detect and manipulate the internal spatial structure of fully compensated topological antiferromagnets4-9. The layer-locked Berry curvature represents a first step towards spatial engineering of the Berry phase through effects such as layer-specific moiré potential.

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