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1.
Gastroenterology ; 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39393543

RESUMEN

BACKGROUND AND AIMS: Therapy failure in patients with metastatic colorectal cancer (mCRC, ∼80% occur in the liver) remains an overarching challenge. Preclinical studies demonstrated that HER3 promotes CRC cell survival, but therapies blocking the neuregulin-induced canonical HER3 signaling have made little impact in the clinic. Recent studies suggest that the liver microenvironment promotes CRC growth by activating HER3 in a neuregulin-independent fashion, thus elucidation of these mechanisms may reveal new strategies for treating patients with mCRC. METHODS: Patient-derived primary liver endothelial cells (ECs) were used to interrogate EC-CRC crosstalk. We conducted proteomic analysis to identify EC-secreted factor(s) that triggers non-canonical HER3 activation in CRC, and determined the subsequent effects on mCRC using diverse murine mCRC models. In vitro studies with genetic and pharmacological interventions were used to map the non-canonical HER3 pathway. RESULTS: We demonstrated that EC-secreted leucine-rich alpha-2-glycoprotein 1 (LRG1) directly binds and activates HER3 and promotes CRC growth distinct from neuregulin, the canonical HER3 ligand. Blocking host-derived LRG1 by gene knockout or a neutralizing antibody impaired mCRC outgrowth in the liver and prolonged mouse survival. We identified protein synthesis activated by the PI3K-PDK1-RSK-eIF4B axis as the biologically relevant signaling cascade downstream of the LRG1-HER3 interaction, which was not blocked by conventional HER3-specific antibodies that failed in prior clinical trials. CONCLUSIONS: LRG1 is a novel HER3 ligand and mediates liver-mCRC crosstalk. The LRG1-HER3 signaling axis is distinct from canonical HER3 signaling and represents a new therapeutic opportunity to treat patients with mCRC, and potentially other types of liver metastases.

2.
Brief Bioinform ; 24(1)2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36472568

RESUMEN

Accounting for cell type compositions has been very successful at analyzing high-throughput data from heterogeneous tissues. Differential gene expression analysis at cell type level is becoming increasingly popular, yielding biomarker discovery in a finer granularity within a particular cell type. Although several computational methods have been developed to identify cell type-specific differentially expressed genes (csDEG) from RNA-seq data, a systematic evaluation is yet to be performed. Here, we thoroughly benchmark six recently published methods: CellDMC, CARseq, TOAST, LRCDE, CeDAR and TCA, together with two classical methods, csSAM and DESeq2, for a comprehensive comparison. We aim to systematically evaluate the performance of popular csDEG detection methods and provide guidance to researchers. In simulation studies, we benchmark available methods under various scenarios of baseline expression levels, sample sizes, cell type compositions, expression level alterations, technical noises and biological dispersions. Real data analyses of three large datasets on inflammatory bowel disease, lung cancer and autism provide evaluation in both the gene level and the pathway level. We find that csDEG calling is strongly affected by effect size, baseline expression level and cell type compositions. Results imply that csDEG discovery is a challenging task itself, with room to improvements on handling low signal-to-noise ratio and low expression genes.


Asunto(s)
Perfilación de la Expresión Génica , Programas Informáticos , Perfilación de la Expresión Génica/métodos , RNA-Seq , Simulación por Computador , Relación Señal-Ruido , Análisis de Secuencia de ARN/métodos
3.
Brief Bioinform ; 24(3)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37039682

RESUMEN

RNA methylation has emerged recently as an active research domain to study post-transcriptional alteration in gene expression regulation. Various types of RNA methylation, including N6-methyladenosine (m6A), are involved in human disease development. As a newly developed sequencing biotechnology to quantify the m6A level on a transcriptome-wide scale, MeRIP-seq expands RNA epigenetics study in both basic and clinical applications, with an upward trend. One of the fundamental questions in RNA methylation data analysis is to identify the Differentially Methylated Regions (DMRs), by contrasting cases and controls. Multiple statistical approaches have been recently developed for DMR detection, but there is a lack of a comprehensive evaluation for these analytical methods. Here, we thoroughly assess all eight existing methods for DMR calling, using both synthetic and real data. Our simulation adopts a Gamma-Poisson model and logit linear framework, and accommodates various sample sizes and DMR proportions for benchmarking. For all methods, low sensitivities are observed among regions with low input levels, but they can be drastically boosted by an increase in sample size. TRESS and exomePeak2 perform the best using metrics of detection precision, FDR, type I error control and runtime, though hampered by low sensitivity. DRME and exomePeak obtain high sensitivities, at the expense of inflated FDR and type I error. Analyses on three real datasets suggest differential preference on identified DMR length and uniquely discovered regions, between these methods.


Asunto(s)
ARN , Transcriptoma , Humanos , Análisis de Secuencia de ARN/métodos , ARN/genética , Metilación , Adenosina/genética , Adenosina/metabolismo
4.
Bioinformatics ; 40(8)2024 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-39153205

RESUMEN

SUMMARY: Recent methodology advances in computational signal deconvolution have enabled bulk transcriptome data analysis at a finer cell-type level. Through deconvolution, identifying cell-type-specific differentially expressed (csDE) genes is drawing increasing attention in clinical applications. However, researchers still face a number of difficulties in adopting csDE genes detection methods in practice, especially in their experimental design. Here we present cypress, the first experimental design and statistical power analysis tool in csDE genes identification. This tool can reliably model purified cell-type-specific (CTS) profiles, cell-type compositions, biological and technical variations, offering a high-fidelity simulator for bulk RNA-seq convolution and deconvolution. cypress conducts simulation and evaluates the impact of multiple influencing factors, by various statistical metrics, to help researchers optimize experimental design and conduct power analysis. AVAILABILITY AND IMPLEMENTATION: cypress is an open-source R/Bioconductor package at https://bioconductor.org/packages/cypress/.


Asunto(s)
Perfilación de la Expresión Génica , Programas Informáticos , Humanos , Perfilación de la Expresión Génica/métodos , Transcriptoma
5.
Plant Physiol ; 195(1): 502-517, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38243831

RESUMEN

Apple Valsa canker, caused by the ascomycete fungus Valsa mali, employs virulence effectors to disturb host immunity and poses a substantial threat to the apple industry. However, our understanding of how V. mali effectors regulate host defense responses remains limited. Here, we identified the V. mali effector Vm_04797, which was upregulated during the early infection stage. Vm_04797, a secreted protein, suppressed Inverted formin 1 (INF1)-triggered cell death in Nicotiana benthamiana and performed virulence functions inside plant cells. Vm_04797 deletion mutants showed substantially reduced virulence toward apple. The adaptor protein MdAP-2ß positively regulated apple Valsa canker resistance and was targeted and degraded by Vm_04797 via the ubiquitination pathway. The in vitro analysis suggested that Vm_04797 possesses E3 ubiquitin ligase activity. Further analysis revealed that MdAP-2ß is involved in autophagy by interacting with Malus domestica autophagy protein 16 MdATG16 and promoting its accumulation. By degrading MdAP-2ß, Vm_04797 inhibited autophagic flux, thereby disrupting the defense response mediated by autophagy. Our findings provide insights into the molecular mechanisms employed by the effectors of E3 ubiquitin ligase activity in ascomycete fungi to regulate host immunity.


Asunto(s)
Ascomicetos , Autofagia , Proteínas Fúngicas , Malus , Nicotiana , Enfermedades de las Plantas , Proteínas de Plantas , Enfermedades de las Plantas/microbiología , Malus/microbiología , Malus/metabolismo , Malus/genética , Ascomicetos/patogenicidad , Ascomicetos/fisiología , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Nicotiana/microbiología , Nicotiana/genética , Nicotiana/metabolismo , Interacciones Huésped-Patógeno , Virulencia , Inmunidad de la Planta/genética , Ubiquitinación , Resistencia a la Enfermedad/genética
6.
Plant Physiol ; 194(4): 2755-2770, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38235781

RESUMEN

Apple Valsa canker (AVC) is a devastating disease of apple (Malus × domestica), caused by Valsa mali (Vm). The Cysteine-rich secretory protein, Antigen 5, and Pathogenesis-related protein 1 (CAP) superfamily protein PATHOGENESIS-RELATED PROTEIN 1-LIKE PROTEIN c (VmPR1c) plays an important role in the pathogenicity of Vm. However, the mechanisms through which it exerts its virulence function in Vm-apple interactions remain unclear. In this study, we identified an apple valine-glutamine (VQ)-motif-containing protein, MdVQ29, as a VmPR1c target protein. MdVQ29-overexpressing transgenic apple plants showed substantially enhanced AVC resistance as compared with the wild type. MdVQ29 interacted with the transcription factor MdWRKY23, which was further shown to bind to the promoter of the jasmonic acid (JA) signaling-related gene CORONATINE INSENSITIVE 1 (MdCOI1) and activate its expression to activate the JA signaling pathway. Disease evaluation in lesion areas on infected leaves showed that MdVQ29 positively modulated apple resistance in a MdWRKY23-dependent manner. Furthermore, MdVQ29 promoted the transcriptional activity of MdWRKY23 toward MdCOI1. In addition, VmPR1c suppressed the MdVQ29-enhanced transcriptional activation activity of MdWRKY23 by promoting the degradation of MdVQ29 and inhibiting MdVQ29 expression and the MdVQ29-MdWRKY23 interaction, thereby interfering with the JA signaling pathway and facilitating Vm infection. Overall, our results demonstrate that VmPR1c targets MdVQ29 to manipulate the JA signaling pathway to regulate immunity. Thus, this study provides an important theoretical basis and guidance for mining and utilizing disease-resistance genetic resources for genetically improving apples.


Asunto(s)
Ascomicetos , Ciclopentanos , Malus , Oxilipinas , Malus/genética , Malus/metabolismo , Glutamina/metabolismo , Valina/metabolismo , Transducción de Señal , Enfermedades de las Plantas/genética
7.
Nat Chem Biol ; 19(10): 1276-1285, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37550431

RESUMEN

Phe-Met-Arg-Phe-amide (FMRFamide)-activated sodium channels (FaNaCs) are a family of channels activated by the neuropeptide FMRFamide, and, to date, the underlying ligand gating mechanism remains unknown. Here we present the high-resolution cryo-electron microscopy structures of Aplysia californica FaNaC in both apo and FMRFamide-bound states. AcFaNaC forms a chalice-shaped trimer and possesses several notable features, including two FaNaC-specific insertion regions, a distinct finger domain and non-domain-swapped transmembrane helix 2 in the transmembrane domain (TMD). One FMRFamide binds to each subunit in a cleft located in the top-most region of the extracellular domain, with participation of residues from the neighboring subunit. Bound FMRFamide adopts an extended conformation. FMRFamide binds tightly to A. californica FaNaC in an N terminus-in manner, which causes collapse of the binding cleft and induces large local conformational rearrangements. Such conformational changes are propagated downward toward the TMD via the palm domain, possibly resulting in outward movement of the TMD and dilation of the ion conduction pore.


Asunto(s)
Activación del Canal Iónico , Neuropéptidos , FMRFamida/metabolismo , FMRFamida/farmacología , Microscopía por Crioelectrón , Neuropéptidos/metabolismo , Canales de Sodio/química , Canales de Sodio/metabolismo
8.
PLoS Comput Biol ; 20(2): e1011875, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38346081

RESUMEN

Recently, novel biotechnologies to quantify RNA modifications became an increasingly popular choice for researchers who study epitranscriptome. When studying RNA methylations such as N6-methyladenosine (m6A), researchers need to make several decisions in its experimental design, especially the sample size and a proper statistical power. Due to the complexity and high-throughput nature of m6A sequencing measurements, methods for power calculation and study design are still currently unavailable. In this work, we propose a statistical power assessment tool, magpie, for power calculation and experimental design for epitranscriptome studies using m6A sequencing data. Our simulation-based power assessment tool will borrow information from real pilot data, and inspect various influential factors including sample size, sequencing depth, effect size, and basal expression ranges. We integrate two modules in magpie: (i) a flexible and realistic simulator module to synthesize m6A sequencing data based on real data; and (ii) a power assessment module to examine a set of comprehensive evaluation metrics.


Asunto(s)
Metilación de ARN , ARN , ARN/genética , ARN/metabolismo , Metilación , Secuenciación de Nucleótidos de Alto Rendimiento
9.
Plant J ; 115(3): 803-819, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37118888

RESUMEN

Effectors play important roles in facilitating the infection of plant pathogenic fungi. However, the gene expression regulatory mechanism of effector genes, in particular at the post-transcriptional level, is largely unknown. In this study, we uncovered the post-transcriptional regulation of an effector gene VmSP1 by a miRNA-like RNA (Vm-milR16) facilitating the infection of the apple tree Valsa canker pathogen Valsa mali. Genetic and molecular biological assays indicated that the expression of VmSP1 could be suppressed by Vm-milR16-mediated mRNA cleavage in a sequence-specific manner. During V. mali infection, Vm-milR16 was downregulated, whereas VmSP1 was upregulated, which further indicated the regulation relationship. VmSP1 was further demonstrated to be a secreted protein and could suppress plant immunity. Deletion of VmSP1 did not affect the vegetative growth but significantly reduced the virulence of V. mali. Further study indicated that VmSP1 could interact with the transcription factor MdbHLH189 of apple. Transiently overexpression of MdbHLH189 enhanced host resistance to V. mali by enhancing the expression of apple defense-related genes, together with the increased callose deposition. Silencing of MdbHLH189 compromised host resistance to V. mali. Our findings uncovered the novel epigenetic regulation mechanism of a virulence-associated effector gene mediated by a fungal milRNA at the post-transcriptional level, and the results enriched the understanding of the function and action mechanism of effectors in tree pathogenic fungi.


Asunto(s)
Malus , MicroARNs , MicroARNs/genética , MicroARNs/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Epigénesis Genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Malus/metabolismo
10.
J Am Chem Soc ; 146(23): 15887-15896, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38825776

RESUMEN

Oxide thin films grown on metal surfaces have wide applications in catalysis and beyond owing to their unique surface structures compared to their bulk counterparts. Despite extensive studies, the atomic structures of copper surface oxides on Cu(111), commonly referred to as "44" and "29", have remained elusive. In this work, we demonstrated an approach for the structural determination of oxide surfaces using element-specific scanning tunneling microscopy (STM) imaging enhanced by functionalized tips. This approach enabled us to resolve the atomic structures of "44" and "29" surface oxides, which were further corroborated by noncontact atomic force microscopy (nc-AFM) measurements and Monte Carlo (MC) simulations. The stoichiometry of the "44" and "29" frameworks was identified as Cu23O16 and Cu16O11, respectively. Contrary to the conventional hypothesis, we observed ordered Cu vacancies within the "44" structure manifesting as peanut-shaped cavities in the hexagonal lattice. Similarly, a combination of Cu and O vacancies within the "29" structure leads to bean-shaped cavities within the pentagonal lattice. Our study has thus resolved the decades-long controversy on the atomic structures of "44" and "29" surface oxides, advancing our understanding of copper oxidation processes and introducing a robust framework for the analysis of complex oxide surfaces.

11.
Am J Transplant ; 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39447750

RESUMEN

Allograft fibrosis is increasingly detected in graft biopsies as the postoperative period extends, potentially emerging as a pivotal determinant of long-term graft function and graft survival among pediatric recipients. Currently, there is a paucity of non-invasive diagnostic tools capable of identifying allograft fibrosis in pediatric recipients of liver transplants. This study involved 507 pediatric liver transplant patients and developed a novel blood-based diagnostic assay, PT-LIFE, to noninvasively distinguish allograft fibrosis using blood samples, clinical data, and biopsy outcomes. The PT-LIFE assay was derived from a matrix of 23 variables and validated in two independent cohorts. It integrates three biomarkers (LECT2, YKL-40, FBLN3) with an AUROC of 0.91. In the pooled analysis, a PT-LIFE score lower than 0.12 identified LAFSc 0-2 with a sensitivity of 91.9%, whereas scores above 0.29 indicated LAFSc 3-6, with a specificity of 88.4%. The PT-LIFE assay presents as a promising non-invasive diagnostic tool for the detection of allograft fibrosis in pediatric liver transplant recipients. The study is registered with ClinicalTrials.gov, identifier NCT05308628.

12.
J Gene Med ; 26(1): e3644, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38072402

RESUMEN

BACKGROUND: Melanoma, a frequently encountered cutaneous malignancy characterized by a poor prognosis, persists in presenting formidable challenges despite the advancement in molecularly targeted drugs designed to improve survival rates significantly. Unfortunately, as more therapeutic choices have developed over time, the gradual emergence of drug resistance has become a notable impediment to the effectiveness of these therapeutic interventions. The hepatocyte growth factor (HGF)/c-met signaling pathway has attracted considerable attention, associated with drug resistance stemming from multiple potential mutations within the c-met gene. The activation of the HGF/c-met pathway operates in an autocrine manner in melanoma. Notably, a key player in the regulatory orchestration of HGF/c-met activation is the long non-coding RNA MEG3. METHODS: Melanoma tissues were collected to measure MEG3 expression. In vitro validation was performed on MEG3 to prove its oncogenic roles. Bioinformatic analyses were conducted on the TCGA database to build the MEG3-related score. The immune characteristics and mutation features of the MEG3-related score were explored. RESULTS: We revealed a negative correlation between HGF and MEG3. In melanoma cells, HGF inhibited MEG3 expression by augmenting the methylation of the MEG3 promoter. Significantly, MEG3 exhibits a suppressive impact on the proliferation and migration of melanoma cells, concurrently inhibiting c-met expression. Moreover, a predictive model centered around MEG3 demonstrates notable efficacy in forecasting critical prognostic indicators, immunological profiles, and mutation statuses among melanoma patients. CONCLUSIONS: The present study highlights the potential of MEG3 as a pivotal regulator of c-met, establishing it as a promising candidate for targeted drug development in the ongoing pursuit of effective therapeutic interventions.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/metabolismo , Vemurafenib/farmacología , Vemurafenib/uso terapéutico , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Metilación , Proliferación Celular , Línea Celular Tumoral
13.
J Neuroinflammation ; 21(1): 104, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649932

RESUMEN

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a common neurological complication of anesthesia and surgery in aging individuals. Neuroinflammation has been identified as a hallmark of POCD. However, safe and effective treatments of POCD are still lacking. Itaconate is an immunoregulatory metabolite derived from the tricarboxylic acid cycle that exerts anti-inflammatory effects by activating the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. In this study, we investigated the effects and underlying mechanism of 4-octyl itaconate (OI), a cell-permeable itaconate derivative, on POCD in aged mice. METHODS: A POCD animal model was established by performing aseptic laparotomy in 18-month-old male C57BL/6 mice under isoflurane anesthesia while maintaining spontaneous ventilation. OI was intraperitoneally injected into the mice after surgery. Primary microglia and neurons were isolated and treated to lipopolysaccharide (LPS), isoflurane, and OI. Cognitive function, neuroinflammatory responses, as well as levels of gut microbiota and their metabolites were evaluated. To determine the mechanisms underlying the therapeutic effects of OI in POCD, ML385, an antagonist of Nrf2, was administered intraperitoneally. Cognitive function, neuroinflammatory responses, endogenous neurogenesis, neuronal apoptosis, and Nrf2/extracellular signal-related kinases (ERK) signaling pathway were evaluated. RESULTS: Our findings revealed that OI treatment significantly alleviated anesthesia/surgery-induced cognitive impairment, concomitant with reduced levels of the neuroinflammatory cytokines IL-1ß and IL-6, as well as suppressed activation of microglia and astrocytes in the hippocampus. Similarly, OI treatment inhibited the expression of IL-1ß and IL-6 in LPS and isoflurane-induced primary microglia in vitro. Intraperitoneal administration of OI led to alterations in the gut microbiota and promoted the production of microbiota-derived metabolites associated with neurogenesis. We further confirmed that OI promoted endogenous neurogenesis and inhibited neuronal apoptosis in the hippocampal dentate gyrus of aged mice. Mechanistically, we observed a decrease in Nrf2 expression in hippocampal neurons both in vitro and in vivo, which was reversed by OI treatment. We found that Nrf2 was required for OI treatment to inhibit neuroinflammation in POCD. The enhanced POCD recovery and promotion of neurogenesis triggered by OI exposure were, at least partially, mediated by the activation of the Nrf2/ERK signaling pathway. CONCLUSIONS: Our findings demonstrate that OI can attenuate anesthesia/surgery-induced cognitive impairment by stabilizing the gut microbiota and activating Nrf2 signaling to restrict neuroinflammation and promote neurogenesis. Boosting endogenous itaconate or supplementation with exogenous itaconate derivatives may represent novel strategies for the treatment of POCD.


Asunto(s)
Microbioma Gastrointestinal , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2 , Neurogénesis , Enfermedades Neuroinflamatorias , Complicaciones Cognitivas Postoperatorias , Succinatos , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Masculino , Ratones , Neurogénesis/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Complicaciones Cognitivas Postoperatorias/metabolismo , Enfermedades Neuroinflamatorias/metabolismo , Succinatos/farmacología , Succinatos/uso terapéutico , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Anestesia
14.
J Neuroinflammation ; 21(1): 169, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961424

RESUMEN

BACKGROUND: Understanding the mechanism behind sepsis-associated encephalopathy (SAE) remains a formidable task. This study endeavors to shed light on the complex cellular and molecular alterations that occur in the brains of a mouse model with SAE, ultimately unraveling the underlying mechanisms of this condition. METHODS: We established a murine model using intraperitoneal injection of lipopolysaccharide (LPS) in wild type and Anxa1-/- mice and collected brain tissues for analysis at 0-hour, 12-hour, 24-hour, and 72-hour post-injection. Utilizing advanced techniques such as single-nucleus RNA sequencing (snRNA-seq) and Stereo-seq, we conducted a comprehensive characterization of the cellular responses and molecular patterns within the brain. RESULTS: Our study uncovered notable temporal differences in the response to LPS challenge between Anxa1-/- (annexin A1 knockout) and wild type mice, specifically at the 12-hour and 24-hour time points following injection. We observed a significant increase in the proportion of Astro-2 and Micro-2 cells in these mice. These cells exhibited a colocalization pattern with the vascular subtype Vas-1, forming a distinct region known as V1A2M2, where Astro-2 and Micro-2 cells surrounded Vas-1. Moreover, through further analysis, we discovered significant upregulation of ligands and receptors such as Timp1-Cd63, Timp1-Itgb1, Timp1-Lrp1, as well as Ccl2-Ackr1 and Cxcl2-Ackr1 within this region. In addition, we observed a notable increase in the expression of Cd14-Itgb1, Cd14-Tlr2, and Cd14-C3ar1 in regions enriched with Micro-2 cells. Additionally, Cxcl10-Sdc4 showed broad upregulation in brain regions containing both Micro-2 and Astro-2 cells. Notably, upon LPS challenge, there was an observed increase in Anxa1 expression in the mouse brain. Furthermore, our study revealed a noteworthy increase in mortality rates following Anxa1 knockdown. However, we did not observe substantial differences in the types, numbers, or distribution of other brain cells between Anxa1-/- and wildtype mice over time. Nevertheless, when comparing the 24-hour post LPS injection time point, we observed a significant decrease in the proportion and distribution of Micro-2 and Astro-2 cells in the vicinity of blood vessels in Anxa1-/- mice. Additionally, we noted reduced expression levels of several ligand-receptor pairs including Cd14-Tlr2, Cd14-C3ar1, Cd14-Itgb1, Cxcl10-Sdc4, Ccl2-Ackr1, and Cxcl2-Ackr1. CONCLUSIONS: By combining snRNA-seq and Stereo-seq techniques, our study successfully identified a distinctive cellular colocalization, referred to as a special pathological niche, comprising Astro-2, Micro-2, and Vas-1 cells. Furthermore, we observed an upregulation of ligand-receptor pairs within this niche. These findings suggest a potential association between this cellular arrangement and the underlying mechanisms contributing to SAE or the increased mortality observed in Anxa1 knockdown mice.


Asunto(s)
Astrocitos , Encéfalo , Modelos Animales de Enfermedad , Lipopolisacáridos , Ratones Noqueados , Microglía , Encefalopatía Asociada a la Sepsis , Animales , Ratones , Lipopolisacáridos/toxicidad , Encefalopatía Asociada a la Sepsis/patología , Encefalopatía Asociada a la Sepsis/genética , Encefalopatía Asociada a la Sepsis/metabolismo , Microglía/metabolismo , Microglía/patología , Encéfalo/patología , Encéfalo/metabolismo , Astrocitos/metabolismo , Astrocitos/patología , Análisis de Secuencia de ARN/métodos , Ratones Endogámicos C57BL , Transcriptoma , Masculino
15.
Small ; 20(14): e2308473, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37972267

RESUMEN

Decorating platinum (Pt) with a single atom offers a promising approach to tailoring their catalytic activity. In this study, for the first time, an innovative assistive active sites (AAS) strategy is proposed to construct high-loading (3.46wt.%) single Fe─N4 as AAS, which are further hybridized with small Pt nanoparticles to enhance both oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) activities. For ORR, the target catalyst (Pt/HFeSA-HCS) exhibits a higher mass activity (MA) of 0.98 A mgPt -1 and specific activity (SA) of 1.39 mA cmPt -2 at 0.90 V versus RHE. As for MOR, Pt/HFeSA-HCS shows exceptional MA (3.21 A mgPt -1) and SA (4.27 mA cmPt -2) at peak values, surpassing commercial Pt/C by 15.3 and 11.5 times, respectively. The underlying mechanism behind this AAS strategy is to find that in MOR, Fe─N4 promotes water dissociation, generating more *OH to accelerate the conversion of *CO to CO2. Meanwhile, in ORR, Fe─N4 acts as a competitor to adsorb *OH, weakening Pt─OH bonding and facilitating desorption of *OH on the Pt surface. Constructing AAS that can enhance dual functionality simultaneously can be seen as a successful "kill two birds with one stone" strategy.

16.
J Virol ; 97(2): e0003523, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36744958

RESUMEN

Asp-Glu-Ala-Asp (DEAD) box helicase 3 X-linked (DDX3X) plays important regulatory roles in the replication of many viruses. However, the role of DDX3X in rhabdovirus replication has seldomly been investigated. In this study, snakehead vesiculovirus (SHVV), a kind of fish rhabdovirus, was used to study the role of DDX3X in rhabdovirus replication. DDX3X was identified as an interacting partner of SHVV phosphoprotein (P). The expression level of DDX3X was increased at an early stage of SHVV infection and then decreased to a normal level at a later infection stage. Overexpression of DDX3X promoted, while knockdown of DDX3X using specific small interfering RNAs (siRNAs) suppressed, SHVV replication, indicating that DDX3X was a proviral factor for SHVV replication. The N-terminal and core domains of DDX3X (DDX3X-N and DDX3X-Core) were determined to be the regions responsible for its interaction with SHVV P. Overexpression of DDX3X-Core suppressed SHVV replication by competitively disrupting the interaction between full-length DDX3X and SHVV P, suggesting that full-length DDX3X-P interaction was required for SHVV replication. Mechanistically, DDX3X-mediated promotion of SHVV replication was due not to inhibition of interferon expression but to maintenance of the stability of SHVV P to avoid autophagy-lysosome-dependent degradation. Collectively, our data suggest that DDX3X is hijacked by SHVV P to ensure effective replication of SHVV, which suggests an important anti-SHVV target. This study will help elucidate the role of DDX3X in regulating the replication of rhabdoviruses. IMPORTANCE Growing evidence has suggested that DDX3X plays important roles in virus replication. In one respect, DDX3X inhibits the replication of viruses, including hepatitis B virus, influenza A virus, Newcastle disease virus, duck Tembusu virus, and red-spotted grouper nervous necrosis virus. In another respect, DDX3X is required for the replication of viruses, including hepatitis C virus, Japanese encephalitis virus, West Nile virus, murine norovirus, herpes simplex virus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Because DDX3X has rarely been investigated in rhabdovirus replication, this study aimed at investigating the role of DDX3X in rhabdovirus replication by using the fish rhabdovirus SHVV as a model. We found that DDX3X was required for SHVV replication, with the mechanism that DDX3X interacts with and maintains the stability of SHVV phosphoprotein. Our data provide novel insights into the role of DDX3X in virus replication and will facilitate the design of antiviral drugs against rhabdovirus infection.


Asunto(s)
ARN Helicasas DEAD-box , Perciformes , Fosfoproteínas , Vesiculovirus , Replicación Viral , Animales , ARN Helicasas DEAD-box/genética , Peces , Perciformes/virología , ARN Interferente Pequeño , Vesiculovirus/patogenicidad , Vesiculovirus/fisiología , Proteínas Virales
17.
New Phytol ; 243(3): 1154-1171, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38822646

RESUMEN

Cross-kingdom RNA interference (RNAi) is a crucial mechanism in host-pathogen interactions, with RNA-dependent RNA polymerase (RdRP) playing a vital role in signal amplification during RNAi. However, the role of pathogenic fungal RdRP in siRNAs generation and the regulation of plant-pathogen interactions remains elusive. Using deep sequencing, molecular, genetic, and biochemical approaches, this study revealed that VmRDR2 of Valsa mali regulates VmR2-siR1 to suppress the disease resistance-related gene MdLRP14 in apple. Both VmRDR1 and VmRDR2 are essential for the pathogenicity of V. mali in apple, with VmRDR2 mediating the generation of endogenous siRNAs, including an infection-related siRNA, VmR2-siR1. This siRNA specifically degrades the apple intracellular LRR-RI protein gene MdLRP14 in a sequence-specific manner, and overexpression of MdLRP14 enhances apple resistance against V. mali, which can be suppressed by VmR2-siR1. Conversely, MdLRP14 knockdown reduces resistance. In summary, this study demonstrates that VmRDR2 contributes to the generation of VmR2-siR1, which silences the host's intracellular LRR protein gene, thereby inhibiting host resistance. These findings offer novel insights into the fungi-mediated pathogenicity mechanism through RNAi.


Asunto(s)
Resistencia a la Enfermedad , Malus , Enfermedades de las Plantas , Proteínas de Plantas , Interferencia de ARN , Malus/genética , Malus/microbiología , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Genes de Plantas
18.
Opt Express ; 32(3): 3167-3183, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297544

RESUMEN

Clarifying the aberrations arising from freeform surfaces is of great significance for maximizing the potential of freeform surfaces in the design of optical systems. However, the current precision in calculating aberration contribution of freeform surface terms for non-zero field of view is insufficient, impeding the development of freeform imaging systems with larger field of view. This paper proposes a high-precision analysis of aberration contribution of freeform surface terms based on nodal aberration theory, particularly for non-zero field points. Accurate calculation formulas of aberrations generated by Zernike terms on freeform surface are presented. Design examples illustrate that the calculation error of the provided formulas is 78% less than that of conventional theoretical values. Building upon high-precision analysis, we propose an optimization method for off-axis freeform surface systems and illustrate its effectiveness through the optimization of an off-axis three-mirror system. This research extends the applicability of nodal aberration theory in aberration analysis, offering valuable insights for the optimal design and alignment of optical freeform systems.

19.
Opt Lett ; 49(11): 2942-2945, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824298

RESUMEN

In this Letter, an optically transparent and broadband absorber designed using a multi-objective genetic algorithm (MOGA) is proposed. The absorption of the multilayer lossy frequency selective surface-based absorber is calculated by multilayer absorption equations and equivalent circuit models. To solve the problem of the unbalanced structure absorption bandwidth and thickness, an algorithm is used for optimizing the geometric and sheet resistance parameters of the structure. A multilayer and optically transparent absorber with 90% absorption bandwidth covering a frequency range of 2-18 GHz (S-band to Ku-band) is developed based on the MOGA design method with optical transmittance of 60%. Its total thickness consists of a wavelength of only 0.095, and it has high oblique incidence stability, which makes it useful in the stealth technology and transparent electromagnetic shielding applications.

20.
Ann Hematol ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39402313

RESUMEN

BACKGROUND: Anti-human T lymphocyte porcine immunoglobulin (p-ATG) is a potent immunosuppressive agent derived from porcine sources used in various immunotherapy applications. It is compared with similar products derived from other species, such as rabbit anti-thymocyte globulin (r-ATG) and ATG-Fresenius (ATG-F), which have distinct biological and therapeutic properties. This study aims to elucidate the mechanisms of action and comparative efficacy of p-ATG in relation to r-ATG and ATG-F through a comprehensive in vitro analysis. METHODS: A comparative analysis of p-ATG, r-ATG and ATG-F was performed, focusing on E rosette inhibitory potency, lymphocyte toxic potency, blocking activities of 24 CD molecules, and flow quantitative potency. Flow cytometric analysis was used to quantify these characteristics and assess the potency of the immunoglobulins. RESULTS: p-ATG exhibited lower E rosette inhibitory and lymphocyte toxic potencies compared to r-ATG but was significantly more potent than ATG-F at equivalent concentrations. At protein concentrations above 12.5 µg/mL, p-ATG showed slightly lower potency than r-ATG and much higher potency than ATG-F in flow cytometry assays. Both p-ATG and r-ATG exhibited similar killing effects on lymphocytes within the peripheral blood mononuclear cells (PBMCs), including CD3 + T cells, with a dose-dependent response. Notably, p-ATG displayed more pronounced blocking activities against CD8, CD99, and TCR α/ß compared to r-ATG. CONCLUSION: p-ATG offers certain advantages over r-ATG and ATG-F, particularly in its ability to inhibit specific CD molecules and its overall potency in immunosuppressive assays, providing valuable insights for assisting clinical decision-making regarding the selection of ATG types based on patient-specific needs and treatment objectives.

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