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1.
Nature ; 629(8012): 579-585, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38750235

RESUMEN

Towards realizing the future quantum internet1,2, a pivotal milestone entails the transition from two-node proof-of-principle experiments conducted in laboratories to comprehensive multi-node set-ups on large scales. Here we report the creation of memory-memory entanglement in a multi-node quantum network over a metropolitan area. We use three independent memory nodes, each of which is equipped with an atomic ensemble quantum memory3 that has telecom conversion, together with a photonic server where detection of a single photon heralds the success of entanglement generation. The memory nodes are maximally separated apart for 12.5 kilometres. We actively stabilize the phase variance owing to fibre links and control lasers. We demonstrate concurrent entanglement generation between any two memory nodes. The memory lifetime is longer than the round-trip communication time. Our work provides a metropolitan-scale testbed for the evaluation and exploration of multi-node quantum network protocols and starts a stage of quantum internet research.

2.
Immunity ; 52(5): 767-781.e6, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32277911

RESUMEN

The enzyme cyclic GMP-AMP synthase (cGAS) senses cytosolic DNA in infected and malignant cells and catalyzes the formation of 2'3'cGMP-AMP (cGAMP), which in turn triggers interferon (IFN) production via the STING pathway. Here, we examined the contribution of anion channels to cGAMP transfer and anti-viral defense. A candidate screen revealed that inhibition of volume-regulated anion channels (VRACs) increased propagation of the DNA virus HSV-1 but not the RNA virus VSV. Chemical blockade or genetic ablation of LRRC8A/SWELL1, a VRAC subunit, resulted in defective IFN responses to HSV-1. Biochemical and electrophysiological analyses revealed that LRRC8A/LRRC8E-containing VRACs transport cGAMP and cyclic dinucleotides across the plasma membrane. Enhancing VRAC activity by hypotonic cell swelling, cisplatin, GTPγS, or the cytokines TNF or interleukin-1 increased STING-dependent IFN response to extracellular but not intracellular cGAMP. Lrrc8e-/- mice exhibited impaired IFN responses and compromised immunity to HSV-1. Our findings suggest that cell-to-cell transmission of cGAMP via LRRC8/VRAC channels is central to effective anti-viral immunity.


Asunto(s)
Fibroblastos/inmunología , Interferones/inmunología , Proteínas de la Membrana/inmunología , Nucleótidos Cíclicos/inmunología , Canales Aniónicos Dependientes del Voltaje/inmunología , Animales , Antivirales/inmunología , Antivirales/metabolismo , Efecto Espectador , Línea Celular , Células Cultivadas , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Células HeLa , Herpes Simple/inmunología , Herpes Simple/virología , Herpesvirus Humano 1/inmunología , Herpesvirus Humano 1/fisiología , Humanos , Interferones/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Nucleótidos Cíclicos/metabolismo , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/inmunología , Nucleotidiltransferasas/metabolismo , Canales Aniónicos Dependientes del Voltaje/metabolismo
3.
Nat Immunol ; 16(6): 642-52, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25915733

RESUMEN

Fungal infection stimulates the canonical C-type lectin receptor (CLR) signaling pathway via activation of the tyrosine kinase Syk. Here we identify a crucial role for the tyrosine phosphatase SHP-2 in mediating CLR-induced activation of Syk. Ablation of the gene encoding SHP-2 (Ptpn11; called 'Shp-2' here) in dendritic cells (DCs) and macrophages impaired Syk-mediated signaling and abrogated the expression of genes encoding pro-inflammatory molecules following fungal stimulation. Mechanistically, SHP-2 operated as a scaffold, facilitating the recruitment of Syk to the CLR dectin-1 or the adaptor FcRγ, through its N-SH2 domain and a previously unrecognized carboxy-terminal immunoreceptor tyrosine-based activation motif (ITAM). We found that DC-derived SHP-2 was crucial for the induction of interleukin 1ß (IL-1ß), IL-6 and IL-23 and anti-fungal responses of the TH17 subset of helper T cells in controlling infection with Candida albicans. Together our data reveal a mechanism by which SHP-2 mediates the activation of Syk in response to fungal infection.


Asunto(s)
Candidiasis/inmunología , Células Dendríticas/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/fisiología , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Células Th17/inmunología , Secuencias de Aminoácidos/genética , Animales , Antígenos Fúngicos/inmunología , Células Cultivadas , Citocinas/metabolismo , Activación Enzimática , Mediadores de Inflamación/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Activación de Linfocitos , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Receptores de IgE/genética , Receptores de IgE/metabolismo , Transducción de Señal , Quinasa Syk
4.
Am J Hum Genet ; 110(7): 1162-1176, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37352861

RESUMEN

Large-scale genetic association studies have identified multiple susceptibility loci for nasopharyngeal carcinoma (NPC), but the underlying biological mechanisms remain to be explored. To gain insights into the genetic etiology of NPC, we conducted a follow-up study encompassing 6,907 cases and 10,472 controls and identified two additional NPC susceptibility loci, 9q22.33 (rs1867277; OR = 0.74, 95% CI = 0.68-0.81, p = 3.08 × 10-11) and 17q12 (rs226241; OR = 1.42, 95% CI = 1.26-1.60, p = 1.62 × 10-8). The two additional loci, together with two previously reported genome-wide significant loci, 5p15.33 and 9p21.3, were investigated by high-throughput sequencing for chromatin accessibility, histone modification, and promoter capture Hi-C (PCHi-C) profiling. Using luciferase reporter assays and CRISPR interference (CRISPRi) to validate the functional profiling, we identified PHF2 at locus 9q22.33 as a susceptibility gene. PHF2 encodes a histone demethylase and acts as a tumor suppressor. The risk alleles of the functional SNPs reduced the expression of the target gene PHF2 by inhibiting the enhancer activity of its long-range (4.3 Mb) cis-regulatory element, which promoted proliferation of NPC cells. In addition, we identified CDKN2B-AS1 as a susceptibility gene at locus 9p21.3, and the NPC risk allele of the functional SNP rs2069418 promoted the expression of CDKN2B-AS1 by increasing its enhancer activity. The overexpression of CDKN2B-AS1 facilitated proliferation of NPC cells. In summary, we identified functional SNPs and NPC susceptibility genes, which provides additional explanations for the genetic association signals and helps to uncover the underlying genetic etiology of NPC development.


Asunto(s)
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Estudios de Asociación Genética , Polimorfismo de Nucleótido Simple/genética , Proteínas de Homeodominio/genética
5.
J Immunol ; 213(3): 347-361, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38847616

RESUMEN

The cyclic GMP-AMP synthase (cGAS)-stimulator of IFN genes (STING) pathway is instrumental to antitumor immunity, yet the underlying molecular and cellular mechanisms are complex and still unfolding. A new paradigm suggests that cancer cells' cGAS-synthesized cGAMP can be transferred to tumor-infiltrating immune cells, eliciting STING-dependent IFN-ß response for antitumor immunity. Nevertheless, how the tumor microenvironment may shape this process remains unclear. In this study, we found that extracellular ATP, an immune regulatory molecule widely present in the tumor microenvironment, can potentiate cGAMP transfer, thereby boosting the STING signaling and IFN-ß response in murine macrophages and fibroblasts. Notably, genetic ablation or chemical inhibition of murine volume-regulation anion channel LRRC8/volume-regulated anion channel (VRAC), a recently identified cGAMP transporter, abolished ATP-potentiated cGAMP transfer and STING-dependent IFN-ß response, revealing a crucial role of LRRC8/VRAC in the cross-talk of extracellular ATP and cGAMP. Mechanistically, ATP activation of the P2X family receptors triggered Ca2+ influx and K+ efflux, promoting reactive oxygen species production. Moreover, ATP-evoked K+ efflux alleviated the phosphorylation of VRAC's obligate subunit LRRC8A/SWELL1 on S174. Mutagenesis studies indicated that the phosphorylation of S174 on LRRC8A could act as a checkpoint for VRAC in the steady state and a rheostat of ATP responsiveness. In an MC38-transplanted tumor model, systemically blocking CD39 and ENPP1, hydroxylases of extracellular ATP and cGAMP, respectively, elevated antitumor NK, NKT, and CD8+ T cell responses and restrained tumor growth in mice. Altogether, this study establishes a crucial role of ATP in facilitating LRRC8/VRAC transport cGAMP in the tumor microenvironment and provides new insight into harnessing cGAMP transfer for antitumor immunity.


Asunto(s)
Adenosina Trifosfato , Proteínas de la Membrana , Nucleótidos Cíclicos , Microambiente Tumoral , Animales , Nucleótidos Cíclicos/metabolismo , Ratones , Adenosina Trifosfato/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/inmunología , Microambiente Tumoral/inmunología , Interferón beta/metabolismo , Interferón beta/inmunología , Ratones Endogámicos C57BL , Humanos , Transducción de Señal/inmunología , Ratones Noqueados , Línea Celular Tumoral , Cationes/metabolismo , Neoplasias/inmunología , Neoplasias/metabolismo , Nucleotidiltransferasas/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo
6.
Nature ; 578(7794): 240-245, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32051600

RESUMEN

A quantum internet that connects remote quantum processors1,2 should enable a number of revolutionary applications such as distributed quantum computing. Its realization will rely on entanglement of remote quantum memories over long distances. Despite enormous progress3-12, at present the maximal physical separation achieved between two nodes is 1.3 kilometres10, and challenges for longer distances remain. Here we demonstrate entanglement of two atomic ensembles in one laboratory via photon transmission through city-scale optical fibres. The atomic ensembles function as quantum memories that store quantum states. We use cavity enhancement to efficiently create atom-photon entanglement13-15 and we use quantum frequency conversion16 to shift the atomic wavelength to telecommunications wavelengths. We realize entanglement over 22 kilometres of field-deployed fibres via two-photon interference17,18 and entanglement over 50 kilometres of coiled fibres via single-photon interference19. Our experiment could be extended to nodes physically separated by similar distances, which would thus form a functional segment of the atomic quantum network, paving the way towards establishing atomic entanglement over many nodes and over much longer distances.

7.
Proc Natl Acad Sci U S A ; 120(8): e2210643120, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36795751

RESUMEN

Microglia play a critical role in the pathogenic process of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease (AD). Upon pathological stimulation, microglia are converted from a surveillant to an overactivated phenotype. However, the molecular characters of proliferating microglia and their contributions to the pathogenesis of neurodegeneration remain unclear. Here, we identify chondroitin sulfate proteoglycan 4 (Cspg4, also known as neural/glial antigen 2)-expressing microglia as a specific subset of microglia with proliferative capability during neurodegeneration. We found that the percentage of Cspg4+ microglia was increased in mouse models of PD. The transcriptomic analysis of Cspg4+ microglia revealed that the subcluster Cspg4high microglia displayed a unique transcriptomic signature, which was characterized by the enrichment of orthologous cell cycle genes and a lower expression of genes responsible for neuroinflammation and phagocytosis. Their gene signatures were also distinct from that of known disease-associated microglia. The proliferation of quiescent Cspg4high microglia was evoked by pathological α-synuclein. Following the transplantation in the adult brain with the depletion of endogenous microglia, Cspg4high microglia grafts showed higher survival rates than their Cspg4- counterparts. Consistently, Cspg4high microglia were detected in the brain of AD patients and displayed the expansion in animal models of AD. These findings suggest that Cspg4high microglia are one of the origins of microgliosis during neurodegeneration and may open up a avenue for the treatment of neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Ratones , Animales , Microglía/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Fagocitosis
8.
Development ; 149(12)2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35616329

RESUMEN

The perinuclear theca (PT) is a cytoskeletal element encapsulating the sperm nucleus; however, the physiological roles of the PT in sperm are largely uncertain. Here, we reveal that ACTRT1, ACTRT2, ACTL7A and ACTL9 proteins interact to form a multimeric complex and localize to the subacrosomal region of spermatids. Furthermore, we engineered Actrt1-knockout (KO) mice to define the functions of ACTRT1. Despite normal sperm count and motility, Actrt1-KO males were severely subfertile owing to a deficiency in fertilization. Loss of ACTRT1 caused a high incidence of malformed heads and detachment of acrosomes from sperm nuclei, caused by loosened acroplaxome structure during spermiogenesis. Furthermore, Actrt1-KO sperm showed reduced ACTL7A and PLCζ protein content as a potential cause of fertilization defects. Moreover, we reveal that ACTRT1 anchors developing acrosomes to the nucleus, likely by interacting with the inner acrosomal membrane protein SPACA1 and the nuclear envelope proteins PARP11 and SPATA46. Loss of ACTRT1 weakened the interaction between ACTL7A and SPACA1. Our study and recent findings of ACTL7A/ACTL9-deficient sperm together reveal that the sperm PT-specific ARP complex mediates the acrosome-nucleus connection.


Asunto(s)
Acrosoma , Infertilidad Masculina , Acrosoma/metabolismo , Animales , Humanos , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Proteínas de Microfilamentos/metabolismo , Espermátides/metabolismo , Espermatogénesis/genética , Espermatozoides/metabolismo
9.
Nat Immunol ; 14(1): 72-81, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23202271

RESUMEN

Act1 is an essential adaptor in interleukin 17 (IL-17)-mediated signaling and is recruited to the receptor for IL-17 after stimulation with IL-17. Here we found that Act1 was a 'client' protein of the molecular chaperone hsp90. The D10N variant of Act1 (Act1(D10N)) that is linked to susceptibility to psoriasis was defective in its interaction with hsp90, which resulted in a global loss of Act1 function. Act1-deficient mice modeled the mechanistic link between loss of Act1 function and susceptibility to psoriasis. Although Act1 was necessary for IL-17-mediated inflammation, Act1-deficient mice had a hyperactive response of the T(H)17 subset of helper T cells and developed spontaneous IL-22-dependent skin inflammation. In the absence of IL-17 signaling, IL-22 was the main contributor to skin inflammation, which provides a molecular mechanism for the association of Act1(D10N) with psoriasis susceptibility.


Asunto(s)
Conexina 43/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Fragmentos de Péptidos/metabolismo , Psoriasis/inmunología , Células Th17/inmunología , Animales , Línea Celular , Conexina 43/genética , Conexina 43/inmunología , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Humanos , Interleucina-17/metabolismo , Ratones , Ratones Noqueados , Chaperonas Moleculares/genética , Mutación/genética , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Polimorfismo Genético , Unión Proteica/genética , Unión Proteica/inmunología , Psoriasis/genética , Transducción de Señal
10.
Plant Physiol ; 195(3): 1893-1905, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546393

RESUMEN

Respiration provides energy, substrates, and precursors to support physiological changes of the fruit during climacteric ripening. A key substrate of respiration is oxygen that needs to be supplied to the fruit in a passive way by gas transfer from the environment. Oxygen gradients may develop within the fruit due to its bulky size and the dense fruit tissues, potentially creating hypoxia that may have a role in the spatial development of ripening. This study presents a 3D reaction-diffusion model using tomato (Solanum lycopersicum) fruit as a test subject, combining the multiscale fruit geometry generated from magnetic resonance imaging and microcomputed tomography with varying respiration kinetics and contrasting boundary resistances obtained through independent experiments. The model predicted low oxygen levels in locular tissue under atmospheric conditions, and the oxygen level was markedly lower upon scar occlusion, aligning with microsensor profiling results. The locular region was in a hypoxic state, leading to its low aerobic respiration with high CO2 accumulation by fermentative respiration, while the rest of the tissues remained well oxygenated. The model further revealed that the hypoxia is caused by a combination of diffusion resistances and respiration rates of the tissue. Collectively, this study reveals the existence of the respiratory gas gradients and its biophysical causes during tomato fruit ripening, providing richer information for future studies on localized endogenous ethylene biosynthesis and fruit ripening.


Asunto(s)
Frutas , Oxígeno , Solanum lycopersicum , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/fisiología , Solanum lycopersicum/metabolismo , Frutas/crecimiento & desarrollo , Frutas/fisiología , Oxígeno/metabolismo , Difusión , Modelos Biológicos , Respiración de la Célula , Imagen por Resonancia Magnética/métodos , Microtomografía por Rayos X
11.
FASEB J ; 38(15): e23852, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39101942

RESUMEN

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative ailment that causes slow cartilage degeneration, aberrant bone remodeling, and persistent discomfort, leading to a considerable reduction in the patient's life quality. Current treatment options for TMJOA have limited efficacy. This investigation aimed to explore a potential strategy for halting or reversing the progression of TMJOA through the utilization of exosomes (EXOs) derived from urine-derived stem cells (USCs). The USC-EXOs were obtained through microfiltration and ultrafiltration techniques, followed by their characterization using particle size analysis, electron microscopy, and immunoblotting. Subsequently, an in vivo model of TMJOA induced by mechanical force was established. To assess the changes in the cartilage of TMJOA treated with USC-EXOs, we performed histology analysis using hematoxylin-eosin staining, immunohistochemistry, and histological scoring. Our findings indicate that the utilization of USC-EXOs yields substantial reductions in TMJOA, while concurrently enhancing the structural integrity and smoothness of the compromised condylar cartilage surface. Additionally, USC-EXOs exhibit inhibitory effects on osteoclastogenic activity within the subchondral bone layer of the condylar cartilage, as well as attenuated apoptosis in the rat TMJ in response to mechanical injury. In conclusion, USC-EXOs hold considerable promise as a potential therapeutic intervention for TMJOA.


Asunto(s)
Exosomas , Osteoartritis , Articulación Temporomandibular , Exosomas/metabolismo , Animales , Osteoartritis/terapia , Osteoartritis/patología , Osteoartritis/metabolismo , Ratas , Masculino , Humanos , Articulación Temporomandibular/metabolismo , Articulación Temporomandibular/patología , Células Madre/citología , Células Madre/metabolismo , Ratas Sprague-Dawley , Orina/citología , Trastornos de la Articulación Temporomandibular/terapia , Trastornos de la Articulación Temporomandibular/metabolismo , Trastornos de la Articulación Temporomandibular/patología , Femenino , Cartílago Articular/patología , Cartílago Articular/metabolismo
12.
Cell Mol Life Sci ; 81(1): 65, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281222

RESUMEN

Loss of GLI-Similar 3 (GLIS3) function in mice and humans causes congenital hypothyroidism (CH). In this study, we demonstrate that GLIS3 protein is first detectable at E15.5 of murine thyroid development, a time at which GLIS3 target genes, such as Slc5a5 (Nis), become expressed. This, together with observations showing that ubiquitous Glis3KO mice do not display major changes in prenatal thyroid gland morphology, indicated that CH in Glis3KO mice is due to dyshormonogenesis rather than thyroid dysgenesis. Analysis of GLIS3 in postnatal thyroid suggested a link between GLIS3 protein expression and blood TSH levels. This was supported by data showing that treatment with TSH, cAMP, or adenylyl cyclase activators or expression of constitutively active PKA enhanced GLIS3 protein stability and transcriptional activity, indicating that GLIS3 activity is regulated at least in part by TSH/TSHR-mediated activation of PKA. The TSH-dependent increase in GLIS3 transcriptional activity would be critical for the induction of GLIS3 target gene expression, including several thyroid hormone (TH) biosynthetic genes, in thyroid follicular cells of mice fed a low iodine diet (LID) when blood TSH levels are highly elevated. Like TH biosynthetic genes, the expression of cell cycle genes is suppressed in ubiquitous Glis3KO mice fed a LID; however, in thyroid-specific Glis3 knockout mice, the expression of cell cycle genes was not repressed, in contrast to TH biosynthetic genes. This indicated that the inhibition of cell cycle genes in ubiquitous Glis3KO mice is dependent on changes in gene expression in GLIS3 target tissues other than the thyroid.


Asunto(s)
Glándula Tiroides , Factores de Transcripción , Animales , Ratones , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica , Proteínas Represoras/genética , Glándula Tiroides/metabolismo , Hormonas Tiroideas/metabolismo , Tirotropina/genética , Tirotropina/metabolismo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo
13.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34969857

RESUMEN

Type I interferons (IFNs) are the first frontline of the host innate immune response against invading pathogens. Herein, we characterized an unknown protein encoded by phospholipase A2 inhibitor and LY6/PLAUR domain-containing (PINLYP) gene that interacted with TBK1 and induced type I IFN in a TBK1- and IRF3-dependent manner. Loss of PINLYP impaired the activation of IRF3 and production of IFN-ß induced by DNA virus, RNA virus, and various Toll-like receptor ligands in multiple cell types. Because PINLYP deficiency in mice engendered an early embryonic lethality in mice, we generated a conditional mouse in which PINLYP was depleted in dendritic cells. Mice lacking PINLYP in dendritic cells were defective in type I IFN induction and more susceptible to lethal virus infection. Thus, PINLYP is a positive regulator of type I IFN innate immunity and important for effective host defense against viral infection.


Asunto(s)
Células Dendríticas/inmunología , Inhibidores Enzimáticos/inmunología , Inmunidad Innata , Interferón beta/inmunología , Animales , Línea Celular , Infecciones por Virus ADN/genética , Infecciones por Virus ADN/inmunología , Virus ADN/genética , Virus ADN/inmunología , Humanos , Interferón beta/genética , Ratones , Ratones Noqueados , Infecciones por Virus ARN/genética , Infecciones por Virus ARN/inmunología , Virus ARN/genética , Virus ARN/inmunología
14.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35217598

RESUMEN

Seed vigor in crops is important in terms of improving grain quality and germplasm conservation; however, little is known about its regulatory mechanisms through the encoded proteome and gene network. Comparative analyses of transcriptome (RNA sequencing [RNA-seq]) and broadly targeted metabolic profiling of two subspecific rice cultivars with distinct seed vigor during accelerated aging revealed various biological pathways and metabolic processes as key influences explaining trait differences. RNA-seq coexpression regulatory network analyses identified several transcription factors, including bZIP23 and bZIP42, that act as nodes in the gene network. Importantly, transgenic seeds of overexpression of bZIP23 enhanced seed vigor, whereas its gene knockout reduced seed vigor, suggesting that the protein it encodes functions as a positive regulator. Similarly, overexpression and knockout of PER1A that encodes a key player in the detoxification pathway enhanced and decreased seed vigor, respectively. We further demonstrated a direct interaction of the PER1A promoter with bZIP23 in seeds, which activates the expression of PER1A, and the genetic evidence suggested that bZIP23 most likely functions in a common pathway with and acts upstream of PER1A to modulate seed vigor. In addition, the control of seed vigor by the bZIP23-PER1A module was connected with that of the abscisic acid signaling pathway. Collectively, we revealed the genetic architecture of variation in seed vigor and uncovered the bZIP23-PER1A-mediated detoxification pathway that enhances the trait in rice.


Asunto(s)
Genoma de Planta , Vigor Híbrido , Metaboloma , Oryza/embriología , Peroxirredoxinas/metabolismo , Proteínas de Plantas/metabolismo , Semillas/fisiología , Ácido Abscísico/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Oryza/genética , Oryza/metabolismo , Semillas/metabolismo , Transducción de Señal
15.
J Neurosci ; 43(15): 2665-2681, 2023 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-36898835

RESUMEN

The Slack channel (KCNT1, Slo2.2) is a sodium-activated and chloride-activated potassium channel that regulates heart rate and maintains the normal excitability of the nervous system. Despite intense interest in the sodium gating mechanism, a comprehensive investigation to identify the sodium-sensitive and chloride-sensitive sites has been missing. In the present study, we identified two potential sodium-binding sites in the C-terminal domain of the rat Slack channel by conducting electrophysical recordings and systematic mutagenesis of cytosolic acidic residues in the rat Slack channel C terminus. In particular, by taking advantage of the M335A mutant, which results in the opening of the Slack channel in the absence of cytosolic sodium, we found that among the 92 screened negatively charged amino acids, E373 mutants could completely remove sodium sensitivity of the Slack channel. In contrast, several other mutants showed dramatic decreases in sodium sensitivity but did not abolish it altogether. Furthermore, molecular dynamics (MD) simulations performed at the hundreds of nanoseconds timescale revealed one or two sodium ions at the E373 position or an acidic pocket composed of several negatively charged residues. Moreover, the MD simulations predicted possible chloride interaction sites. By screening predicted positively charged residues, we identified R379 as a chloride interaction site. Thus, we conclude that the E373 site and the D863/E865 pocket are two potential sodium-sensitive sites, while R379 is a chloride interaction site in the Slack channel.SIGNIFICANCE STATEMENT The research presented here identified two distinct sodium and one chloride interaction sites located in the intracellular C-terminal domain of the Slack (Slo2.2, KCNT1) channel. Identification of the sites responsible for the sodium and chloride activation of the Slack channel sets its gating property apart from other potassium channels in the BK channel family. This finding sets the stage for future functional and pharmacological studies of this channel.


Asunto(s)
Canales de potasio activados por Sodio , Animales , Ratas , Cloruros/metabolismo , Canales de potasio activados por Sodio/metabolismo , Sodio/metabolismo
16.
J Cell Physiol ; 239(2): e31129, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38192063

RESUMEN

Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective hematopoiesis. Accumulating evidence has shown that macrophages (MΦs) are important components in the regulation of tumor progression and hematopoietic stem cells (HSCs). However, the roles of bone marrow (BM) MΦs in regulating normal and malignant hematopoiesis in different clinical stages of MDS are largely unknown. Age-paired patients with lower-risk MDS (N = 15), higher-risk MDS (N = 15), de novo acute myeloid leukemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. Flow cytometry analysis showed increased pro-inflammatory monocyte subsets and a decreased classically activated (M1) MΦs/alternatively activated (M2) MΦs ratio in the BM of patients with higher-risk MDS compared to lower-risk MDS. BM MФs from patients with higher-risk MDS and AML showed impaired phagocytosis activity but increased migration compared with lower-risk MDS group. AML BM MΦs showed markedly higher S100A8/A9 levels than lower-risk MDS BM MΦs. More importantly, coculture experiments suggested that the HSC supporting abilities of BM MΦs from patients with higher-risk MDS decreased, whereas the malignant cell supporting abilities increased compared with lower-risk MDS. Gene Ontology enrichment comparing BM MΦs from lower-risk MDS and higher-risk MDS for genes was involved in hematopoiesis- and immunity-related pathways. Our results suggest that BM MΦs are involved in ineffective hematopoiesis in patients with MDS, which indicates that repairing aberrant BM MΦs may represent a promising therapeutic approach for patients with MDS.


Asunto(s)
Infecciones , Macrófagos , Síndromes Mielodisplásicos , Humanos , Médula Ósea/patología , Hematopoyesis , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Macrófagos/patología , Síndromes Mielodisplásicos/genética , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Infecciones/patología
17.
J Am Chem Soc ; 146(4): 2411-2418, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38234111

RESUMEN

Nanographene C222, which consists of a planar graphenic plane containing 222 carbon atoms, holds the record as the largest planar nanographene synthesized to date. However, its complete insolubility makes the processing of C222 difficult. Here we addressed this issue by introducing peripheral substituents perpendicular to the graphene plane, effectively disrupting the interlayer stacking and endowing C222 with good solubility. We also found that the electron-withdrawing substituents played a crucial role in the cyclodehydrogenation process, converting the dendritic polyphenylene precursor to C222. After disrupting the interlayer stacking, the introduction of only a few peripheral carboxylic groups allowed C222 to dissolve in phosphate buffer saline, reaching a concentration of up to 0.5 mg/mL. Taking advantage of the good photosensitizing and photothermal properties of the inner C222 core, the resulting water-soluble C222 emerged as a single-component agent for both photothermal and photodynamic tumor therapy, exhibiting an impressive tumor inhibition rate of 96%.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Terapia Fototérmica , Fotoquimioterapia/métodos , Neoplasias/tratamiento farmacológico
18.
PLoS Med ; 21(5): e1004389, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38728364

RESUMEN

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Camptotecina , Cetuximab , Neoplasias Colorrectales , Fluorouracilo , Leucovorina , Neoplasias Hepáticas , Compuestos Organoplatinos , Proteínas Proto-Oncogénicas B-raf , Humanos , Cetuximab/administración & dosificación , Cetuximab/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Masculino , Persona de Mediana Edad , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/tratamiento farmacológico , Femenino , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Leucovorina/uso terapéutico , Leucovorina/administración & dosificación , Fluorouracilo/uso terapéutico , Fluorouracilo/administración & dosificación , Compuestos Organoplatinos/uso terapéutico , Compuestos Organoplatinos/administración & dosificación , Proteínas Proto-Oncogénicas B-raf/genética , Anciano , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Camptotecina/administración & dosificación , Resultado del Tratamiento , Proteínas ras/genética
19.
Biochem Cell Biol ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39116458

RESUMEN

Diabetic nephropathy (DN) is one of the most common complications of diabetes. Our previous study showed that CD38 knockout (CD38KO) mice had protective effects on many diseases. However, the roles and mechanisms of CD38 in DN remain unknown. Here, DN mice were generated by HFD feeding plus streptozotocin (STZ) injection in male CD38KO and CD38flox mice. Mesangial cells (SV40 MES 13 cells) were used to mimic the injury of DN with palmitic acid (PA) treatment in vitro. Our results showed that CD38 expression was significantly increased in kidney of diabetic CD38flox mice and SV40 MES 13 cells treated with PA. CD38KO mice were significantly resistant to diabetes-induced renal injury. Moreover, CD38 deficiency markedly decreased HFD/STZ-induced lipid accumulation, fibrosis and oxidative stress in kidney tissue. In contrast, overexpression of CD38 aggravated PA-induced lipid accumulation and oxidative stress. CD38 deficiency increased expression of SIRT3, while overexpression of CD38 decreased its expression. More importantly, 3-TYP, an inhibitor of SIRT3, significantly enhanced PA-induced lipid accumulation and oxidative stress in CD38 overexpressing cell lines. In conclusion, our results demonstrated that CD38 deficiency prevented DN by inhibiting lipid accumulation and oxidative stress through activation of the SIRT3 pathway.

20.
Br J Haematol ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39099079

RESUMEN

The objective of this study was to identify independent prognostic factors of viral encephalitis (VE) after allogeneic haematopoietic stem cell transplantation (allo-HSCT) and establish a prognostic model to identify post-transplant VE patients with a greater likelihood of mortality. Among 5380 patients in our centre from 2014 to 2022, 211 patients who developed VE after allo-HSCT were reviewed in this retrospective study. Prognostic factors were selected, and a prognostic model was constructed using Cox regression analysis. The model was subsequently validated and estimated using the area under the receiver operating characteristic curve (AUC), a calibration plot and decision curve analysis (DCA). Glasgow Coma Scale score <9, lesions >3 lobes on magnetic resonance imaging and severe thrombocytopenia were identified as independent prognostic risk factors for VE patients who underwent allo-HSCT. The prognostic model GTM (GTM is an abbreviation for a model composed of three risk factors: GCS score <9, severe thrombocytopenia [platelet count <20 000 per microliter], and lesions >3 lobes on MRI) was established according to the regression coefficients. The validated internal AUC was 0.862 (95% confidence interval [CI], 0.773-0.950), and the external AUC was 0.815 (95% CI, 0.708-0.922), indicating strong discriminatory ability. Furthermore, we constructed calibration plots that demonstrated good consistency between the predicted outcomes and the observed outcomes. DCA exhibited high accuracy in this system, leading to potential benefits for patients.

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