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1.
Nature ; 618(7967): 1072-1077, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37196676

RESUMO

Plasma membrane rupture (PMR) in dying cells undergoing pyroptosis or apoptosis requires the cell-surface protein NINJ11. PMR releases pro-inflammatory cytoplasmic molecules, collectively called damage-associated molecular patterns (DAMPs), that activate immune cells. Therefore, inhibiting NINJ1 and PMR may limit the inflammation that is associated with excessive cell death. Here we describe an anti-NINJ1 monoclonal antibody that specifically targets mouse NINJ1 and blocks oligomerization of NINJ1, preventing PMR. Electron microscopy studies showed that this antibody prevents NINJ1 from forming oligomeric filaments. In mice, inhibition of NINJ1 or Ninj1 deficiency ameliorated hepatocellular PMR induced with TNF plus D-galactosamine, concanavalin A, Jo2 anti-Fas agonist antibody or ischaemia-reperfusion injury. Accordingly, serum levels of lactate dehydrogenase, the liver enzymes alanine aminotransaminase and aspartate aminotransferase, and the DAMPs interleukin 18 and HMGB1 were reduced. Moreover, in the liver ischaemia-reperfusion injury model, there was an attendant reduction in neutrophil infiltration. These data indicate that NINJ1 mediates PMR and inflammation in diseases driven by aberrant hepatocellular death.


Assuntos
Anticorpos Monoclonais , Membrana Celular , Inflamação , Fígado , Fatores de Crescimento Neural , Traumatismo por Reperfusão , Animais , Camundongos , Alanina Transaminase , Alarminas , Anticorpos Monoclonais/imunologia , Aspartato Aminotransferases , Moléculas de Adesão Celular Neuronais/antagonistas & inibidores , Moléculas de Adesão Celular Neuronais/deficiência , Moléculas de Adesão Celular Neuronais/imunologia , Moléculas de Adesão Celular Neuronais/ultraestrutura , Morte Celular , Membrana Celular/patologia , Membrana Celular/ultraestrutura , Concanavalina A , Galactosamina , Hepatócitos/patologia , Hepatócitos/ultraestrutura , Inflamação/patologia , Lactato Desidrogenases , Fígado/patologia , Microscopia Eletrônica , Fatores de Crescimento Neural/antagonistas & inibidores , Fatores de Crescimento Neural/deficiência , Fatores de Crescimento Neural/imunologia , Fatores de Crescimento Neural/ultraestrutura , Infiltração de Neutrófilos , Traumatismo por Reperfusão/patologia
2.
Nature ; 612(7939): 246-251, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36385532

RESUMO

A step towards the next generation of high-capacity, noise-resilient communication and computing technologies is a substantial increase in the dimensionality of information space and the synthesis of superposition states on an N-dimensional (N > 2) Hilbert space featuring exotic group symmetries. Despite the rapid development of photonic devices and systems, on-chip information technologies are mostly limited to two-level systems owing to the lack of sufficient reconfigurability to satisfy the stringent requirement for 2(N - 1) degrees of freedom, intrinsically associated with the increase of synthetic dimensionalities. Even with extensive efforts dedicated to recently emerged vector lasers and microcavities for the expansion of dimensionalities1-10, it still remains a challenge to actively tune the diversified, high-dimensional superposition states of light on demand. Here we demonstrate a hyperdimensional, spin-orbit microlaser for chip-scale flexible generation and manipulation of arbitrary four-level states. Two microcavities coupled through a non-Hermitian synthetic gauge field are designed to emit spin-orbit-coupled states of light with six degrees of freedom. The vectorial state of the emitted laser beam in free space can be mapped on a Bloch hypersphere defining an SU(4) symmetry, demonstrating dynamical generation and reconfiguration of high-dimensional superposition states with high fidelity.


Assuntos
Comunicação , Tecnologia da Informação , Fótons , Tecnologia
3.
EMBO J ; 42(13): e112998, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37211868

RESUMO

Brassinosteroids (BRs) are important plant hormones involved in many aspects of development. Here, we show that BRASSINOSTEROID SIGNALING KINASEs (BSKs), key components of the BR pathway, are precisely controlled via de-S-acylation mediated by the defense hormone salicylic acid (SA). Most Arabidopsis BSK members are substrates of S-acylation, a reversible protein lipidation that is essential for their membrane localization and physiological function. We establish that SA interferes with the plasma membrane localization and function of BSKs by decreasing their S-acylation levels, identifying ABAPT11 (ALPHA/BETA HYDROLASE DOMAIN-CONTAINING PROTEIN 17-LIKE ACYL PROTEIN THIOESTERASE 11) as an enzyme whose expression is quickly induced by SA. ABAPT11 de-S-acylates most BSK family members, thus integrating BR and SA signaling for the control of plant development. In summary, we show that BSK-mediated BR signaling is regulated by SA-induced protein de-S-acylation, which improves our understanding of the function of protein modifications in plant hormone cross talk.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Brassinosteroides/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Salicílico/metabolismo , Arabidopsis/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Acilação , Regulação da Expressão Gênica de Plantas
4.
Plant Cell ; 36(6): 2375-2392, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38470570

RESUMO

Homeodomain (HD) proteins regulate embryogenesis in animals such as the fruit fly (Drosophila melanogaster), often in a concentration-dependent manner. HD-leucine zipper (Zip) IV family genes are unique to plants and often function in the L1 epidermal cell layer. However, our understanding of the roles of HD-Zip IV family genes in plant morphogenesis is limited. In this study, we investigated the morphogenesis of tomato (Solanum lycopersicum) multicellular trichomes, a type of micro-organ in plants. We found that a gradient of the HD-Zip IV regulator Woolly (Wo) coordinates spatially polarized cell division and cell expansion in multicellular trichomes. Moreover, we identified a TEOSINTE BRANCHED1, CYCLOIDEA, and PROLIFERATING CELL NUCLEAR ANTIGEN BINDING FACTOR (TCP) transcription factor-encoding gene, SlBRANCHED2a (SlBRC2a), as a key downstream target of Wo that regulates the transition from cell division to cell expansion. High levels of Wo promote cell division in apical trichome cells, whereas in basal trichome cells, Wo mediates a negative feedback loop with SlBRC2a that forces basal cells to enter endoreduplication. The restricted high and low activities of Wo pattern the morphogenesis of tomato multicellular trichomes. These findings provide insights into the functions of HD-Zip IV genes during plant morphogenesis.


Assuntos
Regulação da Expressão Gênica de Plantas , Morfogênese , Proteínas de Plantas , Solanum lycopersicum , Tricomas , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Solanum lycopersicum/citologia , Tricomas/crescimento & desenvolvimento , Tricomas/genética , Tricomas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Morfogênese/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Divisão Celular
5.
Nature ; 589(7843): 586-590, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33299183

RESUMO

Legumes, unlike other plants, have the ability to establish symbiosis with nitrogen-fixing rhizobia. It has been theorized that a unique property of legume root cortical cells enabled the initial establishment of rhizobial symbiosis1-3. Here we show that a SHORTROOT-SCARECROW (SHR-SCR) stem cell program in cortical cells of the legume Medicago truncatula specifies their distinct fate. Regulatory elements drive the cortical expression of SCR, and stele-expressed SHR protein accumulates in cortical cells of M. truncatula but not Arabidopsis thaliana. The cortical SHR-SCR network is conserved across legume species, responds to rhizobial signals, and initiates legume-specific cortical cell division for de novo nodule organogenesis and accommodation of rhizobia. Ectopic activation of SHR and SCR in legumes is sufficient to induce root cortical cell division. Our work suggests that acquisition of the cortical SHR-SCR module enabled cell division coupled to rhizobial infection in legumes. We propose that this event was central to the evolution of rhizobial endosymbiosis.


Assuntos
Diferenciação Celular , Linhagem da Célula , Medicago truncatula/citologia , Medicago truncatula/metabolismo , Proteínas de Plantas/metabolismo , Nodulação , Arabidopsis/citologia , Arabidopsis/metabolismo , Divisão Celular , Citocininas/metabolismo , Evolução Molecular , Medicago truncatula/embriologia , Proteínas de Plantas/genética , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Rhizobium/metabolismo , Transdução de Sinais , Simbiose/genética
6.
Proc Natl Acad Sci U S A ; 121(20): e2322625121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709915

RESUMO

Soft robots often draw inspiration from nature to navigate different environments. Although the inching motion and crawling motion of caterpillars have been widely studied in the design of soft robots, the steering motion with local bending control remains challenging. To address this challenge, we explore modular origami units which constitute building blocks for mimicking the segmented caterpillar body. Based on this concept, we report a modular soft Kresling origami crawling robot enabled by electrothermal actuation. A compact and lightweight Kresling structure is designed, fabricated, and characterized with integrated thermal bimorph actuators consisting of liquid crystal elastomer and polyimide layers. With the modular design and reprogrammable actuation, a multiunit caterpillar-inspired soft robot composed of both active units and passive units is developed for bidirectional locomotion and steering locomotion with precise curvature control. We demonstrate the modular design of the Kresling origami robot with an active robotic module picking up cargo and assembling with another robotic module to achieve a steering function. The concept of modular soft robots can provide insight into future soft robots that can grow, repair, and enhance functionality.

7.
Proc Natl Acad Sci U S A ; 120(42): e2308496120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812720

RESUMO

Human diseases involve metabolic alterations. Metabolomic profiles have served as a vital biomarker for the early identification of high-risk individuals and disease prevention. However, current approaches can only characterize individual key metabolites, without taking into account the reality that complex diseases are multifactorial, dynamic, heterogeneous, and interdependent. Here, we leverage a statistical physics model to combine all metabolites into bidirectional, signed, and weighted interaction networks and trace how the flow of information from one metabolite to the next causes changes in health state. Viewing a disease outcome as the consequence of complex interactions among its interconnected components (metabolites), we integrate concepts from ecosystem theory and evolutionary game theory to model how the health state-dependent alteration of a metabolite is shaped by its intrinsic properties and through extrinsic influences from its conspecifics. We code intrinsic contributions as nodes and extrinsic contributions as edges into quantitative networks and implement GLMY homology theory to analyze and interpret the topological change of health state from symbiosis to dysbiosis and vice versa. The application of this model to real data allows us to identify several hub metabolites and their interaction webs, which play a part in the formation of inflammatory bowel diseases. The findings by our model could provide important information on drug design to treat these diseases and beyond.


Assuntos
Ecossistema , Metabolômica , Humanos , Modelos Estatísticos , Biomarcadores/metabolismo , Física
8.
Proc Natl Acad Sci U S A ; 120(45): e2304848120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903254

RESUMO

Ecological divergence without geographic isolation, as an early speciation process that may lead finally to reproductive isolation through natural selection, remains a captivating topic in evolutionary biology. However, the pattern of genetic divergence underlying this process across the genome may vary between species and mating systems. Here, we present evidence that Brachypodium stacei, an annual and highly selfing grass model species, has undergone sympatric ecological divergence without geographic isolation. Genomic, transcriptomic, and metabolomic analyses together with lab experiments mimicking the two opposite environmental conditions suggest that diploid B. stacei populations have diverged sympatrically in two slopes characterized by distinct biomes at Evolution Canyon I (ECI), Mount Carmel, Israel. Despite ongoing gene flow, primarily facilitated by seed dispersal, the level of gene flow has progressively decreased over time. This local adaptation involves the scattered divergence of many unlinked loci across the total genome that include both coding genes and noncoding regions. Additionally, we have identified significant differential expressions of genes related to the ABA signaling pathway and contrasting metabolome composition between the arid- vs. forest-adapted B. stacei populations in ECI. These results suggest that multiple small loci involved in environmental responses act additively to account for ecological adaptations by this selfing species in contrasting environments.


Assuntos
Brachypodium , Brachypodium/genética , Diploide , Isolamento Reprodutivo , Ecossistema , Genoma de Planta/genética , Especiação Genética
9.
Am J Pathol ; 194(7): 1248-1261, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38599461

RESUMO

Mucosal-associated invariant T (MAIT) cells are essential in defending against infection. Sepsis is a systemic inflammatory response to infection and a leading cause of death. The relationship between the overall competency of the host immune response and disease severity is not fully elucidated. This study identified a higher proportion of circulating MAIT17 with expression of IL-17A and retinoic acid receptor-related orphan receptor γt in patients with sepsis. The proportion of MAIT17 was correlated with the severity of sepsis. Single-cell RNA-sequencing analysis revealed an enhanced expression of lactate dehydrogenase A (LDHA) in MAIT17 in patients with sepsis. Cell-culture experiments demonstrated that phosphoinositide 3-kinase-LDHA signaling was required for retinoic acid receptor-related orphan receptor γt expression in MAIT17. Finally, the elevated levels of plasma IL-18 promoted the differentiation of circulating MAIT17 cells in sepsis. In summary, this study reveals a new role of circulating MAIT17 in promoting sepsis severity and suggests the phosphoinositide 3-kinase-LDHA signaling as a driving force in MAIT17 responses.


Assuntos
Diferenciação Celular , Células T Invariantes Associadas à Mucosa , Sepse , Humanos , Sepse/imunologia , Sepse/patologia , Sepse/sangue , Células T Invariantes Associadas à Mucosa/imunologia , Células T Invariantes Associadas à Mucosa/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Idoso , Interleucina-17/metabolismo , Interleucina-17/sangue , Transdução de Sinais , Fosfatidilinositol 3-Quinases/metabolismo
10.
Nat Immunol ; 14(6): 584-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23624556

RESUMO

Interleukin 17 (IL-17)-committed γδ T cells (γδT17 cells) participate in many immune responses, but their developmental requirements and subset specific functions remain poorly understood. Here we report that a commonly used CD45.1(+) congenic C57BL/6 mouse substrain is characterized by selective deficiency in Vγ4(+) γδT17 cells. This trait was due to a spontaneous mutation in the gene encoding the transcription factor Sox13 that caused an intrinsic defect in development of those cells in the neonatal thymus. The γδT17 cells migrated from skin to lymph nodes at low rates. In a model of psoriasis-like dermatitis, the Vγ4(+) γδT17 cell subset expanded considerably in lymph nodes and homed to inflamed skin. Sox13-mutant mice were protected from psoriasis-like skin changes, which identified a role for Sox13-dependent γδT17 cells in this inflammatory condition.


Assuntos
Autoantígenos/imunologia , Dermatite/imunologia , Interleucina-17/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Animais Recém-Nascidos , Autoantígenos/genética , Autoantígenos/metabolismo , Células Cultivadas , Dermatite/genética , Dermatite/metabolismo , Citometria de Fluxo , Interleucina-17/genética , Interleucina-17/metabolismo , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Antígenos Comuns de Leucócito/metabolismo , Linfonodos/imunologia , Linfonodos/metabolismo , Linfonodos/patologia , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Endogâmicos NOD , Camundongos Knockout , Mutação , Psoríase/genética , Psoríase/imunologia , Psoríase/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/metabolismo , Timo/imunologia , Timo/metabolismo , Timo/patologia
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