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1.
Cell ; 186(17): 3577-3592.e18, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37499659

RESUMO

Hybrid sterility restricts the utilization of superior heterosis of indica-japonica inter-subspecific hybrids. In this study, we report the identification of RHS12, a major locus controlling male gamete sterility in indica-japonica hybrid rice. We show that RHS12 consists of two genes (iORF3/DUYAO and iORF4/JIEYAO) that confer preferential transmission of the RHS12-i type male gamete into the progeny, thereby forming a natural gene drive. DUYAO encodes a mitochondrion-targeted protein that interacts with OsCOX11 to trigger cytotoxicity and cell death, whereas JIEYAO encodes a protein that reroutes DUYAO to the autophagosome for degradation via direct physical interaction, thereby detoxifying DUYAO. Evolutionary trajectory analysis reveals that this system likely formed de novo in the AA genome Oryza clade and contributed to reproductive isolation (RI) between different lineages of rice. Our combined results provide mechanistic insights into the genetic basis of RI as well as insights for strategic designs of hybrid rice breeding.


Assuntos
Tecnologia de Impulso Genético , Oryza , Hibridização Genética , Oryza/genética , Melhoramento Vegetal/métodos , Isolamento Reprodutivo , Infertilidade das Plantas
2.
Cell ; 184(2): 404-421.e16, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33357445

RESUMO

Hepatocellular carcinoma (HCC) has high relapse and low 5-year survival rates. Single-cell profiling in relapsed HCC may aid in the design of effective anticancer therapies, including immunotherapies. We profiled the transcriptomes of ∼17,000 cells from 18 primary or early-relapse HCC cases. Early-relapse tumors have reduced levels of regulatory T cells, increased dendritic cells (DCs), and increased infiltrated CD8+ T cells, compared with primary tumors, in two independent cohorts. Remarkably, CD8+ T cells in recurrent tumors overexpressed KLRB1 (CD161) and displayed an innate-like low cytotoxic state, with low clonal expansion, unlike the classical exhausted state observed in primary HCC. The enrichment of these cells was associated with a worse prognosis. Differential gene expression and interaction analyses revealed potential immune evasion mechanisms in recurrent tumor cells that dampen DC antigen presentation and recruit innate-like CD8+ T cells. Our comprehensive picture of the HCC ecosystem provides deeper insights into immune evasion mechanisms associated with tumor relapse.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Análise de Célula Única , Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Regulação Neoplásica da Expressão Gênica , Humanos , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Células Mieloides/metabolismo , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/imunologia , Fenótipo , RNA-Seq , Microambiente Tumoral
3.
Cell ; 183(5): 1264-1281.e20, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33091337

RESUMO

The HLA-DR15 haplotype is the strongest genetic risk factor for multiple sclerosis (MS), but our understanding of how it contributes to MS is limited. Because autoreactive CD4+ T cells and B cells as antigen-presenting cells are involved in MS pathogenesis, we characterized the immunopeptidomes of the two HLA-DR15 allomorphs DR2a and DR2b of human primary B cells and monocytes, thymus, and MS brain tissue. Self-peptides from HLA-DR molecules, particularly from DR2a and DR2b themselves, are abundant on B cells and thymic antigen-presenting cells. Furthermore, we identified autoreactive CD4+ T cell clones that can cross-react with HLA-DR-derived self-peptides (HLA-DR-SPs), peptides from MS-associated foreign agents (Epstein-Barr virus and Akkermansia muciniphila), and autoantigens presented by DR2a and DR2b. Thus, both HLA-DR15 allomorphs jointly shape an autoreactive T cell repertoire by serving as antigen-presenting structures and epitope sources and by presenting the same foreign peptides and autoantigens to autoreactive CD4+ T cells in MS.


Assuntos
Subtipos Sorológicos de HLA-DR/imunologia , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Alelos , Antígenos/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Reações Cruzadas/imunologia , Feminino , Humanos , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Peptídeos/imunologia , Proteoma/metabolismo , Adulto Jovem
4.
Cell ; 179(5): 1057-1067.e14, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31730849

RESUMO

The transition to a terrestrial environment, termed terrestrialization, is generally regarded as a pivotal event in the evolution and diversification of the land plant flora that changed the surface of our planet. Through phylogenomic studies, a group of streptophyte algae, the Zygnematophyceae, have recently been recognized as the likely sister group to land plants (embryophytes). Here, we report genome sequences and analyses of two early diverging Zygnematophyceae (Spirogloea muscicola gen. nov. and Mesotaenium endlicherianum) that share the same subaerial/terrestrial habitat with the earliest-diverging embryophytes, the bryophytes. We provide evidence that genes (i.e., GRAS and PYR/PYL/RCAR) that increase resistance to biotic and abiotic stresses in land plants, in particular desiccation, originated or expanded in the common ancestor of Zygnematophyceae and embryophytes, and were gained by horizontal gene transfer (HGT) from soil bacteria. These two Zygnematophyceae genomes represent a cornerstone for future studies to understand the underlying molecular mechanism and process of plant terrestrialization.


Assuntos
Evolução Biológica , Embriófitas/genética , Genoma de Planta , Estreptófitas/genética , Ácido Abscísico/farmacologia , Sequência de Aminoácidos , Família Multigênica , Filogenia , Proteínas de Plantas/química , Domínios Proteicos , Estreptófitas/classificação , Simbiose/genética , Sintenia/genética
5.
Cell ; 175(1): 85-100.e23, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30173916

RESUMO

Multiple sclerosis is an autoimmune disease that is caused by the interplay of genetic, particularly the HLA-DR15 haplotype, and environmental risk factors. How these etiologic factors contribute to generating an autoreactive CD4+ T cell repertoire is not clear. Here, we demonstrate that self-reactivity, defined as "autoproliferation" of peripheral Th1 cells, is elevated in patients carrying the HLA-DR15 haplotype. Autoproliferation is mediated by memory B cells in a HLA-DR-dependent manner. Depletion of B cells in vitro and therapeutically in vivo by anti-CD20 effectively reduces T cell autoproliferation. T cell receptor deep sequencing showed that in vitro autoproliferating T cells are enriched for brain-homing T cells. Using an unbiased epitope discovery approach, we identified RASGRP2 as target autoantigen that is expressed in the brain and B cells. These findings will be instrumental to address important questions regarding pathogenic B-T cell interactions in multiple sclerosis and possibly also to develop novel therapies.


Assuntos
Linfócitos B/patologia , Subtipos Sorológicos de HLA-DR/imunologia , Esclerose Múltipla/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/fisiopatologia , Linfócitos B/metabolismo , Encéfalo/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/fisiologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Subtipos Sorológicos de HLA-DR/genética , Humanos , Esclerose Múltipla/genética , Esclerose Múltipla/fisiopatologia , Receptores de Antígenos de Linfócitos T , Células Th1/fisiologia
6.
Cell ; 175(2): 347-359.e14, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30290141

RESUMO

We analyze whole-genome sequencing data from 141,431 Chinese women generated for non-invasive prenatal testing (NIPT). We use these data to characterize the population genetic structure and to investigate genetic associations with maternal and infectious traits. We show that the present day distribution of alleles is a function of both ancient migration and very recent population movements. We reveal novel phenotype-genotype associations, including several replicated associations with height and BMI, an association between maternal age and EMB, and between twin pregnancy and NRG1. Finally, we identify a unique pattern of circulating viral DNA in plasma with high prevalence of hepatitis B and other clinically relevant maternal infections. A GWAS for viral infections identifies an exceptionally strong association between integrated herpesvirus 6 and MOV10L1, which affects piwi-interacting RNA (piRNA) processing and PIWI protein function. These findings demonstrate the great value and potential of accumulating NIPT data for worldwide medical and genetic analyses.


Assuntos
Povo Asiático/genética , Diagnóstico Pré-Natal/métodos , Adulto , Alelos , China , DNA/genética , Etnicidade/genética , Feminino , Frequência do Gene/genética , Testes Genéticos , Variação Genética/genética , Genética Populacional/métodos , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Migração Humana , Humanos , Gravidez , Análise de Sequência de DNA
7.
Nature ; 632(8023): 108-113, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38961285

RESUMO

Genetic and fragmented palaeoanthropological data suggest that Denisovans were once widely distributed across eastern Eurasia1-3. Despite limited archaeological evidence, this indicates that Denisovans were capable of adapting to a highly diverse range of environments. Here we integrate zooarchaeological and proteomic analyses of the late Middle to Late Pleistocene faunal assemblage from Baishiya Karst Cave on the Tibetan Plateau, where a Denisovan mandible and Denisovan sedimentary mitochondrial DNA were found3,4. Using zooarchaeology by mass spectrometry, we identify a new hominin rib specimen that dates to approximately 48-32 thousand years ago (layer 3). Shotgun proteomic analysis taxonomically assigns this specimen to the Denisovan lineage, extending their presence at Baishiya Karst Cave well into the Late Pleistocene. Throughout the stratigraphic sequence, the faunal assemblage is dominated by Caprinae, together with megaherbivores, carnivores, small mammals and birds. The high proportion of anthropogenic modifications on the bone surfaces suggests that Denisovans were the primary agent of faunal accumulation. The chaîne opératoire of carcass processing indicates that animal taxa were exploited for their meat, marrow and hides, while bone was also used as raw material for the production of tools. Our results shed light on the behaviour of Denisovans and their adaptations to the diverse and fluctuating environments of the late Middle and Late Pleistocene of eastern Eurasia.


Assuntos
Arqueologia , Osso e Ossos , Cavernas , Fósseis , Hominidae , Animais , Ásia , Aves , Osso e Ossos/química , Carnívoros , Europa (Continente) , Herbivoria , História Antiga , Hominidae/classificação , Espectrometria de Massas , Carne/história , Filogenia , Proteômica , Costelas/química , Comportamento de Utilização de Ferramentas
8.
Nature ; 630(8016): 484-492, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811729

RESUMO

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Assuntos
Bactérias , Bacteriófagos , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Bactérias/virologia , Bactérias/genética , Bactérias/imunologia , Bacteriófagos/genética , Bacteriófagos/imunologia , Chryseobacterium/genética , Chryseobacterium/imunologia , Chryseobacterium/virologia , Proteína 9 Associada à CRISPR/química , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/imunologia , Clivagem do DNA , Loci Gênicos/genética , Modelos Moleculares , Domínios Proteicos
9.
Nature ; 627(8005): 783-788, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38538937

RESUMO

Controlling the intensity of emitted light and charge current is the basis of transferring and processing information1. By contrast, robust information storage and magnetic random-access memories are implemented using the spin of the carrier and the associated magnetization in ferromagnets2. The missing link between the respective disciplines of photonics, electronics and spintronics is to modulate the circular polarization of the emitted light, rather than its intensity, by electrically controlled magnetization. Here we demonstrate that this missing link is established at room temperature and zero applied magnetic field in light-emitting diodes2-7, through the transfer of angular momentum between photons, electrons and ferromagnets. With spin-orbit torque8-11, a charge current generates also a spin current to electrically switch the magnetization. This switching determines the spin orientation of injected carriers into semiconductors, in which the transfer of angular momentum from the electron spin to photon controls the circular polarization of the emitted light2. The spin-photon conversion with the nonvolatile control of magnetization opens paths to seamlessly integrate information transfer, processing and storage. Our results provide substantial advances towards electrically controlled ultrafast modulation of circular polarization and spin injection with magnetization dynamics for the next-generation information and communication technology12, including space-light data transfer. The same operating principle in scaled-down structures or using two-dimensional materials will enable transformative opportunities for quantum information processing with spin-controlled single-photon sources, as well as for implementing spin-dependent time-resolved spectroscopies.

10.
Nature ; 632(8027): 1082-1091, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143224

RESUMO

T-lineage acute lymphoblastic leukaemia (T-ALL) is a high-risk tumour1 that has eluded comprehensive genomic characterization, which is partly due to the high frequency of noncoding genomic alterations that result in oncogene deregulation2,3. Here we report an integrated analysis of genome and transcriptome sequencing of tumour and remission samples from more than 1,300 uniformly treated children with T-ALL, coupled with epigenomic and single-cell analyses of malignant and normal T cell precursors. This approach identified 15 subtypes with distinct genomic drivers, gene expression patterns, developmental states and outcomes. Analyses of chromatin topology revealed multiple mechanisms of enhancer deregulation that involve enhancers and genes in a subtype-specific manner, thereby demonstrating widespread involvement of the noncoding genome. We show that the immunophenotypically described, high-risk entity of early T cell precursor ALL is superseded by a broader category of 'early T cell precursor-like' leukaemia. This category has a variable immunophenotype and diverse genomic alterations of a core set of genes that encode regulators of hematopoietic stem cell development. Using multivariable outcome models, we show that genetic subtypes, driver and concomitant genetic alterations independently predict treatment failure and survival. These findings provide a roadmap for the classification, risk stratification and mechanistic understanding of this disease.


Assuntos
Genoma Humano , Genômica , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Criança , Feminino , Humanos , Masculino , Cromatina/genética , Cromatina/metabolismo , Elementos Facilitadores Genéticos/genética , Epigenômica , Regulação Leucêmica da Expressão Gênica , Genoma Humano/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Análise de Célula Única , Transcriptoma/genética , Linfócitos T/citologia , Linfócitos T/patologia
11.
Nature ; 633(8029): 371-379, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39232160

RESUMO

The past two decades has witnessed a remarkable increase in the number of microbial genomes retrieved from marine systems1,2. However, it has remained challenging to translate this marine genomic diversity into biotechnological and biomedical applications3,4. Here we recovered 43,191 bacterial and archaeal genomes from publicly available marine metagenomes, encompassing a wide range of diversity with 138 distinct phyla, redefining the upper limit of marine bacterial genome size and revealing complex trade-offs between the occurrence of CRISPR-Cas systems and antibiotic resistance genes. In silico bioprospecting of these marine genomes led to the discovery of a novel CRISPR-Cas9 system, ten antimicrobial peptides, and three enzymes that degrade polyethylene terephthalate. In vitro experiments confirmed their effectiveness and efficacy. This work provides evidence that global-scale sequencing initiatives advance our understanding of how microbial diversity has evolved in the oceans and is maintained, and demonstrates how such initiatives can be sustainably exploited to advance biotechnology and biomedicine.


Assuntos
Organismos Aquáticos , Biodiversidade , Bioprospecção , Mapeamento Geográfico , Metagenoma , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Archaea/genética , Archaea/classificação , Bactérias/genética , Bactérias/classificação , Tecnologia Biomédica , Bioprospecção/tendências , Biotecnologia , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/isolamento & purificação , Sistemas CRISPR-Cas/genética , Farmacorresistência Bacteriana/genética , Genoma Arqueal/genética , Genoma Bacteriano/genética , Metagenoma/genética , Oceanos e Mares , Filogenia , Água do Mar/microbiologia , Microbiologia da Água
12.
Immunity ; 53(3): 685-696.e3, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32783921

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic poses a current world-wide public health threat. However, little is known about its hallmarks compared to other infectious diseases. Here, we report the single-cell transcriptional landscape of longitudinally collected peripheral blood mononuclear cells (PBMCs) in both COVID-19- and influenza A virus (IAV)-infected patients. We observed increase of plasma cells in both COVID-19 and IAV patients and XIAP associated factor 1 (XAF1)-, tumor necrosis factor (TNF)-, and FAS-induced T cell apoptosis in COVID-19 patients. Further analyses revealed distinct signaling pathways activated in COVID-19 (STAT1 and IRF3) versus IAV (STAT3 and NFκB) patients and substantial differences in the expression of key factors. These factors include relatively increase of interleukin (IL)6R and IL6ST expression in COVID-19 patients but similarly increased IL-6 concentrations compared to IAV patients, supporting the clinical observations of increased proinflammatory cytokines in COVID-19 patients. Thus, we provide the landscape of PBMCs and unveil distinct immune response pathways in COVID-19 and IAV patients.


Assuntos
Infecções por Coronavirus/imunologia , Citocinas/imunologia , Influenza Humana/imunologia , Leucócitos Mononucleares/imunologia , Pneumonia Viral/imunologia , Transdução de Sinais/imunologia , Betacoronavirus/imunologia , COVID-19 , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Pandemias , SARS-CoV-2
13.
Nature ; 618(7967): 934-939, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37380693

RESUMO

The pair density wave (PDW) is an extraordinary superconducting state in which Cooper pairs carry non-zero momentum1,2. Evidence for the existence of intrinsic PDW order in high-temperature (high-Tc) cuprate superconductors3,4 and kagome superconductors5 has emerged recently. However, the PDW order in iron-based high-Tc superconductors has not been observed experimentally. Here, using scanning tunnelling microscopy and spectroscopy, we report the discovery of the PDW state in monolayer iron-based high-Tc Fe(Te,Se) films grown on SrTiO3(001) substrates. The PDW state with a period of λ ≈ 3.6aFe (aFe is the distance between neighbouring Fe atoms) is observed at the domain walls by the spatial electronic modulations of the local density of states, the superconducting gap and the π-phase shift boundaries of the PDW around the vortices of the intertwined charge density wave order. The discovery of the PDW state in the monolayer Fe(Te,Se) film provides a low-dimensional platform to study the interplay between the correlated electronic states and unconventional Cooper pairing in high-Tc superconductors.

14.
Nature ; 616(7955): 77-83, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37020008

RESUMO

Inorganic superionic conductors possess high ionic conductivity and excellent thermal stability but their poor interfacial compatibility with lithium metal electrodes precludes application in all-solid-state lithium metal batteries1,2. Here we report a LaCl3-based lithium superionic conductor possessing excellent interfacial compatibility with lithium metal electrodes. In contrast to a Li3MCl6 (M = Y, In, Sc and Ho) electrolyte lattice3-6, the UCl3-type LaCl3 lattice has large, one-dimensional channels for rapid Li+ conduction, interconnected by La vacancies via Ta doping and resulting in a three-dimensional Li+ migration network. The optimized Li0.388Ta0.238La0.475Cl3 electrolyte exhibits Li+ conductivity of 3.02 mS cm-1 at 30 °C and a low activation energy of 0.197 eV. It also generates a gradient interfacial passivation layer to stabilize the Li metal electrode for long-term cycling of a Li-Li symmetric cell (1 mAh cm-2) for more than 5,000 h. When directly coupled with an uncoated LiNi0.5Co0.2Mn0.3O2 cathode and bare Li metal anode, the Li0.388Ta0.238La0.475Cl3 electrolyte enables a solid battery to run for more than 100 cycles with a cutoff voltage of 4.35 V and areal capacity of more than 1 mAh cm-2. We also demonstrate rapid Li+ conduction in lanthanide metal chlorides (LnCl3; Ln = La, Ce, Nd, Sm and Gd), suggesting that the LnCl3 solid electrolyte system could provide further developments in conductivity and utility.

15.
Nature ; 617(7962): 807-817, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198490

RESUMO

Microbial organisms have key roles in numerous physiological processes in the human body and have recently been shown to modify the response to immune checkpoint inhibitors1,2. Here we aim to address the role of microbial organisms and their potential role in immune reactivity against glioblastoma. We demonstrate that HLA molecules of both glioblastoma tissues and tumour cell lines present bacteria-specific peptides. This finding prompted us to examine whether tumour-infiltrating lymphocytes (TILs) recognize tumour-derived bacterial peptides. Bacterial peptides eluted from HLA class II molecules are recognized by TILs, albeit very weakly. Using an unbiased antigen discovery approach to probe the specificity of a TIL CD4+ T cell clone, we show that it recognizes a broad spectrum of peptides from pathogenic bacteria, commensal gut microbiota and also glioblastoma-related tumour antigens. These peptides were also strongly stimulatory for bulk TILs and peripheral blood memory cells, which then respond to tumour-derived target peptides. Our data hint at how bacterial pathogens and bacterial gut microbiota can be involved in specific immune recognition of tumour antigens. The unbiased identification of microbial target antigens for TILs holds promise for future personalized tumour vaccination approaches.


Assuntos
Antígenos de Neoplasias , Bactérias , Proteínas de Bactérias , Glioblastoma , Linfócitos do Interstício Tumoral , Fragmentos de Peptídeos , Humanos , Antígenos de Neoplasias/imunologia , Proteínas de Bactérias/imunologia , Vacinas Anticâncer/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular Tumoral , Microbioma Gastrointestinal/imunologia , Glioblastoma/imunologia , Glioblastoma/patologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos HLA/imunologia , Linfócitos do Interstício Tumoral/citologia , Linfócitos do Interstício Tumoral/imunologia , Fragmentos de Peptídeos/imunologia , Simbiose , Bactérias/imunologia , Bactérias/patogenicidade
16.
Trends Biochem Sci ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39384487

RESUMO

Strigolactones (SLs) perform versatile functions in plants. The different members of the α/ß-hydrolase superfamily bind and hydrolyze SLs at varying rates to transduce their signal or maintain SL homeostasis. Recent work by Palayam et al. on SL-degrading carboxylesterases (CXEs) uncovers structural elements that determine the mechanism, efficiency of SL hydrolysis, and biological functions.

17.
Nature ; 601(7892): 205-210, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35022592

RESUMO

Fermi liquid theory forms the basis for our understanding of the majority of metals: their resistivity arises from the scattering of well defined quasiparticles at a rate where, in the low-temperature limit, the inverse of the characteristic time scale is proportional to the square of the temperature. However, various quantum materials1-15-notably high-temperature superconductors1-10-exhibit strange-metallic behaviour with a linear scattering rate in temperature, deviating from this central paradigm. Here we show the unexpected signatures of strange metallicity in a bosonic system for which the quasiparticle concept does not apply. Our nanopatterned YBa2Cu3O7-δ (YBCO) film arrays reveal linear-in-temperature and linear-in-magnetic field resistance over extended temperature and magnetic field ranges. Notably, below the onset temperature at which Cooper pairs form, the low-field magnetoresistance oscillates with a period dictated by the superconducting flux quantum, h/2e (e, electron charge; h, Planck's constant). Simultaneously, the Hall coefficient drops and vanishes within the measurement resolution with decreasing temperature, indicating that Cooper pairs instead of single electrons dominate the transport process. Moreover, the characteristic time scale τ in this bosonic system follows a scale-invariant relation without an intrinsic energy scale: h/τ ≈ a(kBT + γµBB), where h is the reduced Planck's constant, a is of order unity7,8,11,12, kB is Boltzmann's constant, T is temperature, µB is the Bohr magneton and γ ≈ 2. By extending the reach of strange-metal phenomenology to a bosonic system, our results suggest that there is a fundamental principle governing their transport that transcends particle statistics.


Assuntos
Elétrons , Supercondutividade , Campos Magnéticos , Metais , Temperatura
18.
Cell ; 148(5): 873-85, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22385957

RESUMO

Tumor heterogeneity presents a challenge for inferring clonal evolution and driver gene identification. Here, we describe a method for analyzing the cancer genome at a single-cell nucleotide level. To perform our analyses, we first devised and validated a high-throughput whole-genome single-cell sequencing method using two lymphoblastoid cell line single cells. We then carried out whole-exome single-cell sequencing of 90 cells from a JAK2-negative myeloproliferative neoplasm patient. The sequencing data from 58 cells passed our quality control criteria, and these data indicated that this neoplasm represented a monoclonal evolution. We further identified essential thrombocythemia (ET)-related candidate mutations such as SESN2 and NTRK1, which may be involved in neoplasm progression. This pilot study allowed the initial characterization of the disease-related genetic architecture at the single-cell nucleotide level. Further, we established a single-cell sequencing method that opens the way for detailed analyses of a variety of tumor types, including those with high genetic complex between patients.


Assuntos
Evolução Clonal , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Análise de Célula Única/métodos , Trombocitemia Essencial/genética , Exoma , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , Mutação
19.
Cell ; 148(5): 886-95, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22385958

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common kidney cancer and has very few mutations that are shared between different patients. To better understand the intratumoral genetics underlying mutations of ccRCC, we carried out single-cell exome sequencing on a ccRCC tumor and its adjacent kidney tissue. Our data indicate that this tumor was unlikely to have resulted from mutations in VHL and PBRM1. Quantitative population genetic analysis indicates that the tumor did not contain any significant clonal subpopulations and also showed that mutations that had different allele frequencies within the population also had different mutation spectrums. Analyses of these data allowed us to delineate a detailed intratumoral genetic landscape at a single-cell level. Our pilot study demonstrates that ccRCC may be more genetically complex than previously thought and provides information that can lead to new ways to investigate individual tumors, with the aim of developing more effective cellular targeted therapies.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Análise de Célula Única/métodos , Proteínas de Ligação a DNA , Exoma , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Nucleares/genética , Filogenia , Projetos Piloto , Análise de Componente Principal , Fatores de Transcrição/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética
20.
Nature ; 589(7841): 214-219, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33408416

RESUMO

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

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