Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 3.447
Filter
1.
Cell ; 187(12): 2935-2951.e19, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38772371

ABSTRACT

Peripheral sensory neurons widely innervate various tissues to continuously monitor and respond to environmental stimuli. Whether peripheral sensory neurons innervate the spleen and modulate splenic immune response remains poorly defined. Here, we demonstrate that nociceptive sensory nerve fibers extensively innervate the spleen along blood vessels and reach B cell zones. The spleen-innervating nociceptors predominantly originate from left T8-T13 dorsal root ganglia (DRGs), promoting the splenic germinal center (GC) response and humoral immunity. Nociceptors can be activated by antigen-induced accumulation of splenic prostaglandin E2 (PGE2) and then release calcitonin gene-related peptide (CGRP), which further promotes the splenic GC response at the early stage. Mechanistically, CGRP directly acts on B cells through its receptor CALCRL-RAMP1 via the cyclic AMP (cAMP) signaling pathway. Activating nociceptors by ingesting capsaicin enhances the splenic GC response and anti-influenza immunity. Collectively, our study establishes a specific DRG-spleen sensory neural connection that promotes humoral immunity, suggesting a promising approach for improving host defense by targeting the nociceptive nervous system.


Subject(s)
Calcitonin Gene-Related Peptide , Germinal Center , Immunity, Humoral , Spleen , Animals , Male , Mice , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Calcitonin Gene-Related Peptide/metabolism , Capsaicin/pharmacology , Cyclic AMP/metabolism , Dinoprostone/metabolism , Ganglia, Spinal/metabolism , Germinal Center/immunology , Mice, Inbred C57BL , Nociceptors/metabolism , Receptor Activity-Modifying Protein 1/metabolism , Sensory Receptor Cells/metabolism , Sensory Receptor Cells/drug effects , Signal Transduction , Spleen/innervation , Spleen/immunology , Female
2.
Cell ; 184(20): 5122-5137.e17, 2021 09 30.
Article in English | MEDLINE | ID: mdl-34534446

ABSTRACT

Natural goal-directed behaviors often involve complex sequences of many stimulus-triggered components. Understanding how brain circuits organize such behaviors requires mapping the interactions between an animal, its environment, and its nervous system. Here, we use brain-wide neuronal imaging to study the full performance of mating by the C. elegans male. We show that as mating unfolds in a sequence of component behaviors, the brain operates similarly between instances of each component but distinctly between different components. When the full sensory and behavioral context is taken into account, unique roles emerge for each neuron. Functional correlations between neurons are not fixed but change with behavioral dynamics. From individual neurons to circuits, our study shows how diverse brain-wide dynamics emerge from the integration of sensory perception and motor actions in their natural context.


Subject(s)
Brain/physiology , Caenorhabditis elegans/physiology , Sensation/physiology , Sexual Behavior, Animal/physiology , Animals , Brain Mapping , Copulation/physiology , Courtship , Databases as Topic , Feedback , Female , Male , Models, Biological , Movement , Neurons/physiology , Rest , Signal Processing, Computer-Assisted , Synapses/physiology , Vulva/physiology
3.
Cell ; 171(7): 1495-1507.e15, 2017 Dec 14.
Article in English | MEDLINE | ID: mdl-29224783

ABSTRACT

Current genome-editing systems generally rely on inducing DNA double-strand breaks (DSBs). This may limit their utility in clinical therapies, as unwanted mutations caused by DSBs can have deleterious effects. CRISPR/Cas9 system has recently been repurposed to enable target gene activation, allowing regulation of endogenous gene expression without creating DSBs. However, in vivo implementation of this gain-of-function system has proven difficult. Here, we report a robust system for in vivo activation of endogenous target genes through trans-epigenetic remodeling. The system relies on recruitment of Cas9 and transcriptional activation complexes to target loci by modified single guide RNAs. As proof-of-concept, we used this technology to treat mouse models of diabetes, muscular dystrophy, and acute kidney disease. Results demonstrate that CRISPR/Cas9-mediated target gene activation can be achieved in vivo, leading to measurable phenotypes and amelioration of disease symptoms. This establishes new avenues for developing targeted epigenetic therapies against human diseases. VIDEO ABSTRACT.


Subject(s)
CRISPR-Cas Systems , Epigenesis, Genetic , Gene Targeting/methods , Genetic Therapy/methods , Muscular Dystrophy, Duchenne/genetics , Muscular Dystrophy, Duchenne/therapy , Utrophin/genetics , Animals , Base Sequence , Disease Models, Animal , Dystrophin/genetics , Interleukin-10/genetics , Klotho Proteins , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Transcriptional Activation
4.
Mol Cell ; 84(8): 1585-1600.e7, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38479385

ABSTRACT

Myriad physiological and pathogenic processes are governed by protein levels and modifications. Controlled protein activity perturbation is essential to studying protein function in cells and animals. Based on Trim-Away technology, we screened for truncation variants of E3 ubiquitinase Trim21 with elevated efficiency (ΔTrim21) and developed multiple ΔTrim21-based targeted protein-degradation systems (ΔTrim-TPD) that can be transfected into host cells. Three ΔTrim-TPD variants are developed to enable chemical and light-triggered programmable activation of TPD in cells and animals. Specifically, we used ΔTrim-TPD for (1) red-light-triggered inhibition of HSV-1 virus proliferation by degrading the packaging protein gD, (2) for chemical-triggered control of the activity of Cas9/dCas9 protein for gene editing, and (3) for blue-light-triggered degradation of two tumor-associated proteins for spatiotemporal inhibition of melanoma tumor growth in mice. Our study demonstrates that multiple ΔTrim21-based controllable TPD systems provide powerful tools for basic biology research and highlight their potential biomedical applications.


Subject(s)
CRISPR-Cas Systems , Gene Editing , Mice , Animals , CRISPR-Associated Protein 9/genetics , CRISPR-Associated Protein 9/metabolism , Proteins/metabolism , Proteolysis , Mammals/metabolism
5.
Nature ; 613(7943): 324-331, 2023 01.
Article in English | MEDLINE | ID: mdl-36599989

ABSTRACT

Pathogens generate ubiquitous selective pressures and host-pathogen interactions alter social behaviours in many animals1-4. However, very little is known about the neuronal mechanisms underlying pathogen-induced changes in social behaviour. Here we show that in adult Caenorhabditis elegans hermaphrodites, exposure to a bacterial pathogen (Pseudomonas aeruginosa) modulates sensory responses to pheromones by inducing the expression of the chemoreceptor STR-44 to promote mating. Under standard conditions, C. elegans hermaphrodites avoid a mixture of ascaroside pheromones to facilitate dispersal5-13. We find that exposure to the pathogenic Pseudomonas bacteria enables pheromone responses in AWA sensory neurons, which mediate attractive chemotaxis, to suppress the avoidance. Pathogen exposure induces str-44 expression in AWA neurons, a process regulated by a transcription factor zip-5 that also displays a pathogen-induced increase in expression in AWA. STR-44 acts as a pheromone receptor and its function in AWA neurons is required for pathogen-induced AWA pheromone response and suppression of pheromone avoidance. Furthermore, we show that C. elegans hermaphrodites, which reproduce mainly through self-fertilization, increase the rate of mating with males after pathogen exposure and that this increase requires str-44 in AWA neurons. Thus, our results uncover a causal mechanism for pathogen-induced social behaviour plasticity, which can promote genetic diversity and facilitate adaptation of the host animals.


Subject(s)
Caenorhabditis elegans , Pheromones , Pseudomonas aeruginosa , Reproduction , Sexual Behavior, Animal , Animals , Female , Male , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/microbiology , Caenorhabditis elegans/physiology , Caenorhabditis elegans Proteins/metabolism , Glycolipids/metabolism , Hermaphroditic Organisms/physiology , Pheromones/metabolism , Pseudomonas aeruginosa/pathogenicity , Pseudomonas aeruginosa/physiology , Receptors, Pheromone/metabolism , Reproduction/physiology , Sensory Receptor Cells/metabolism
6.
Mol Cell ; 78(5): 850-861.e5, 2020 06 04.
Article in English | MEDLINE | ID: mdl-32348779

ABSTRACT

Cas13 has demonstrated unique and broad utility in RNA editing, nucleic acid detection, and disease diagnosis; however, a constantly active Cas enzyme may induce unwanted effects. Bacteriophage- or prophage-region-encoded anti-CRISPR (acr) gene molecules provide the potential to control targeting specificity and potency to allow for optimal RNA editing and nucleic acid detection by spatiotemporally modulating endonuclease activities. Using integrated approaches to screen acrVI candidates and evaluate their effects on Cas13 function, we discovered a series of acrVIA1-7 genes that block the activities of Cas13a. These VI-A CRISPR inhibitors substantially attenuate RNA targeting and editing by Cas13a in human cells. Strikingly, type VI-A anti-CRISPRs (AcrVIAs) also significantly muffle the single-nucleic-acid editing ability of the dCas13a RNA-editing system. Mechanistically, AcrVIA1, -4, -5, and -6 bind LwaCas13a, while AcrVIA2 and -3 can only bind the LwaCas13-crRNA (CRISPR RNA) complex. These identified acr molecules may enable precise RNA editing in Cas13-based application and study of phage-bacterium interaction.


Subject(s)
CRISPR-Associated Proteins/antagonists & inhibitors , CRISPR-Cas Systems/physiology , RNA Editing/physiology , Animals , Bacteria/genetics , Bacteriophages/genetics , CRISPR-Associated Proteins/genetics , CRISPR-Cas Systems/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Editing , HEK293 Cells , Humans , Leptotrichia/genetics , Leptotrichia/metabolism , RNA/genetics , RNA Editing/genetics
7.
EMBO J ; 42(24): e113856, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-37953688

ABSTRACT

Apical-basal polarity is maintained by distinct protein complexes that reside in membrane junctions, and polarity loss in monolayered epithelial cells can lead to formation of multilayers, cell extrusion, and/or malignant overgrowth. Yet, how polarity loss cooperates with intrinsic signals to control directional invasion toward neighboring epithelial cells remains elusive. Using the Drosophila ovarian follicular epithelium as a model, we found that posterior follicle cells with loss of lethal giant larvae (lgl) or Discs large (Dlg) accumulate apically toward germline cells, whereas cells with loss of Bazooka (Baz) or atypical protein kinase C (aPKC) expand toward the basal side of wildtype neighbors. Further studies revealed that these distinct multilayering patterns in the follicular epithelium were determined by epidermal growth factor receptor (EGFR) signaling and its downstream target Pointed, a zinc-finger transcription factor. Additionally, we identified Rho kinase as a Pointed target that regulates formation of distinct multilayering patterns. These findings provide insight into how cell polarity genes and receptor tyrosine kinase signaling interact to govern epithelial cell organization and directional growth that contribute to epithelial tumor formation.


Subject(s)
Cell Polarity , Drosophila Proteins , ErbB Receptors , Animals , Cell Polarity/physiology , Drosophila melanogaster , Drosophila Proteins/metabolism , Epithelial Cells/metabolism , Epithelium/metabolism , ErbB Receptors/genetics , ErbB Receptors/metabolism
8.
EMBO J ; 41(19): e110834, 2022 10 04.
Article in English | MEDLINE | ID: mdl-35950466

ABSTRACT

Many adult tissues and organs including the intestine rely on resident stem cells to maintain homeostasis and regeneration. In mammals, the progenies of intestinal stem cells (ISCs) can dedifferentiate to generate ISCs upon ablation of resident stem cells. However, whether and how mature tissue cells generate ISCs under physiological conditions remains unknown. Here, we show that infection of the Drosophila melanogaster intestine with pathogenic bacteria induces entry of enteroblasts (EBs), which are ISC progenies, into the mitotic cycle through upregulation of epidermal growth factor receptor (EGFR)-Ras signaling. We also show that ectopic activation of EGFR-Ras signaling in EBs is sufficient to drive enteroblast mitosis cell autonomously. Furthermore, we find that the dividing enteroblasts do not gain ISC identity as a prerequisite to divide, and the regenerative ISCs are produced through EB mitosis. Taken together, our work uncovers a new role for EGFR-Ras signaling in driving EB mitosis and replenishing the ISC pool during fly intestinal regeneration, which may have important implications for tissue homeostasis and tumorigenesis in vertebrates.


Subject(s)
Drosophila Proteins , Drosophila , Animals , Cell Proliferation , Drosophila/physiology , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/metabolism , ErbB Receptors/genetics , ErbB Receptors/metabolism , Intestines/physiology , Mammals , Mitosis , Stem Cells/metabolism
9.
PLoS Pathog ; 20(6): e1012271, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38829910

ABSTRACT

Proper transcription regulation by key transcription factors, such as IRF3, is critical for anti-viral defense. Dynamics of enhancer activity play important roles in many biological processes, and epigenomic analysis is used to determine the involved enhancers and transcription factors. To determine new transcription factors in anti-DNA-virus response, we have performed H3K27ac ChIP-Seq and identified three transcription factors, NR2F6, MEF2D and MAFF, in promoting HSV-1 replication. NR2F6 promotes HSV-1 replication and gene expression in vitro and in vivo, but not dependent on cGAS/STING pathway. NR2F6 binds to the promoter of MAP3K5 and activates AP-1/c-Jun pathway, which is critical for DNA virus replication. On the other hand, NR2F6 is transcriptionally repressed by c-Jun and forms a negative feedback loop. Meanwhile, cGAS/STING innate immunity signaling represses NR2F6 through STAT3. Taken together, we have identified new transcription factors and revealed the underlying mechanisms involved in the network between DNA viruses and host cells.


Subject(s)
Herpesvirus 1, Human , Immunity, Innate , Humans , Animals , Herpesvirus 1, Human/immunology , Mice , Virus Replication , Herpes Simplex/immunology , Herpes Simplex/virology , Herpes Simplex/metabolism , Signal Transduction , HEK293 Cells , Repressor Proteins
10.
Nature ; 583(7816): 437-440, 2020 07.
Article in English | MEDLINE | ID: mdl-32434211

ABSTRACT

In December 2019, coronavirus disease 2019 (COVID-19), which is caused by the new coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified in Wuhan (Hubei province, China)1; it soon spread across the world. In this ongoing pandemic, public health concerns and the urgent need for effective therapeutic measures require a deep understanding of the epidemiology, transmissibility and pathogenesis of COVID-19. Here we analysed clinical, molecular and immunological data from 326 patients with confirmed SARS-CoV-2 infection in Shanghai. The genomic sequences of SARS-CoV-2, assembled from 112 high-quality samples together with sequences in the Global Initiative on Sharing All Influenza Data (GISAID) dataset, showed a stable evolution and suggested that there were two major lineages with differential exposure history during the early phase of the outbreak in Wuhan. Nevertheless, they exhibited similar virulence and clinical outcomes. Lymphocytopenia, especially reduced CD4+ and CD8+ T cell counts upon hospital admission, was predictive of disease progression. High levels of interleukin (IL)-6 and IL-8 during treatment were observed in patients with severe or critical disease and correlated with decreased lymphocyte count. The determinants of disease severity seemed to stem mostly from host factors such as age and lymphocytopenia (and its associated cytokine storm), whereas viral genetic variation did not significantly affect outcomes.


Subject(s)
Betacoronavirus/genetics , Betacoronavirus/pathogenicity , Coronavirus Infections/immunology , Coronavirus Infections/virology , Host-Pathogen Interactions/immunology , Lymphopenia/virology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Respiratory Distress Syndrome/virology , Adolescent , Adult , Aged , Aged, 80 and over , Aging , Animals , Asymptomatic Infections/epidemiology , Betacoronavirus/classification , Betacoronavirus/isolation & purification , COVID-19 , China/epidemiology , Cohort Studies , Coronavirus Infections/complications , Coronavirus Infections/epidemiology , Critical Illness/epidemiology , Disease Progression , Evolution, Molecular , Female , Genetic Variation , Genome, Viral/genetics , Hospitalization/statistics & numerical data , Humans , Inflammation Mediators/immunology , Interleukin-6/blood , Interleukin-6/immunology , Interleukin-8/blood , Interleukin-8/immunology , Lymphocyte Count , Lymphopenia/complications , Male , Middle Aged , Pandemics , Phylogeny , Pneumonia, Viral/complications , Pneumonia, Viral/epidemiology , Respiratory Distress Syndrome/complications , SARS-CoV-2 , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Time Factors , Treatment Outcome , Virulence/genetics , Virus Shedding , Young Adult , Zoonoses/transmission , Zoonoses/virology
11.
Nat Immunol ; 14(8): 793-803, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23832071

ABSTRACT

The cell-to-cell transmission of viral resistance is a potential mechanism for amplifying the interferon-induced antiviral response. In this study, we report that interferon-α (IFN-α) induced the transfer of resistance to hepatitis B virus (HBV) from nonpermissive liver nonparenchymal cells (LNPCs) to permissive hepatocytes via exosomes. Exosomes from IFN-α-treated LNPCs were rich in molecules with antiviral activity. Moreover, exosomes from LNPCs were internalized by hepatocytes, which mediated the intercellular transfer of antiviral molecules. Finally, we found that exosomes also contributed to the antiviral response of IFN-α to mouse hepatitis virus A59 and adenovirus in mice. Thus, we propose an antiviral mechanism of IFN-α activity that involves the induction and intercellular transfer of antiviral molecules via exosomes.


Subject(s)
Exosomes/virology , Hepatitis B virus/immunology , Hepatitis B/immunology , Interferon-alpha/pharmacology , Liver/virology , Animals , Exosomes/immunology , Hep G2 Cells , Hepatitis B/drug therapy , Humans , Immunoblotting , Liver/immunology , Mice , Signal Transduction/immunology , Virus Replication/immunology
12.
Hepatology ; 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38904485

ABSTRACT

BACKGROUND AND AIMS: HBsAg serves as an important immune-modulatory factor in chronic hepatitis B. One aspect of such modulation may act through monocytes, which are the major Ag-presenting cells taking up HBsAg. There is evidence for the encapsulation of hepatocellular microRNAs (miRNAs) by HBsAg particles, while its pathobiological significance is unclear. Here, we characterized the miRNA profile in patients with chronic hepatitis B and probed their association with liver inflammation. APPROACHES AND RESULTS: We collected plasma from patients that are treatment-naive with chronic hepatitis B (n = 110) and quantified total/HBsAg-enveloped miRNAs by qRT-PCR and plasma cytokines by ELISA. The biological effects of HBsAg-delivered miRNAs in monocytes were evaluated using multiple approaches. The clinical significance of candidate miRNAs and cytokines was corroborated in patients with HBV-associated advanced liver diseases. The plasma miRNA profile showed 2 major clusters, one significantly associated with HBsAg titer and the other correlated with liver inflammation. Among HBsAg-carried miRNAs, miR-939 displayed the most significant correlation with IL-8. Mechanistically, miR-939 in subviral particles enters monocytes and significantly augments IL-8 production through the mitogen-activated protein kinase (MAPK) p38 signaling pathway. Finally, the findings that miR-939 positively correlated with IL-8 level and inflammation/fibrosis stage in the cohort of HBV-associated advanced liver diseases support its causative role in the progression of liver diseases. CONCLUSIONS: HBsAg particles carry hepatocellular miRNAs, including miR-939, which enter monocytes and alter their functional status, such as IL-8 secretion. Our findings demonstrate that the HBsAg-miR-939-IL-8 axis may play a crucial role in HBV-induced hepatic necro-inflammation and the progression of advanced liver diseases.

13.
FASEB J ; 38(9): e23643, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38703030

ABSTRACT

Secreted phospholipase A2s are involved in the development of obesity, type 2 diabetes mellitus (T2DM) and cardiovascular disease, which have become serious and growing health concerns worldwide. Integration of genome-wide association study and gene co-expression networks analysis showed that the secreted phospholipase A2 group XIIA (PLA2G12A) may participate in hepatic lipids metabolism. Nevertheless, the role of PLA2G12A in lipid metabolism and its potential mechanism remain elusive. Here, we used AAV9 vector carrying human PLA2G12A gene to exogenously express hPLA2G12A in the liver of mice. We demonstrated that the overexpression of hPLA2G12A resulted in a significant decrease in serum lipid levels in wild-type mice fed with chow diet or high-fat diet (HFD). Moreover, hPLA2G12A treatment protected against diet-induced obesity and insulin resistance in mice fed a HFD. Notably, we found that hPLA2G12A treatment confers protection against obesity and hyperlipidemia independent of its enzymatic activity, but rather by increasing physical activity and energy expenditure. Furthermore, we demonstrated that hPLA2G12A treatment induced upregulation of ApoC2 and Cd36 and downregulation of Angptl8, which contributed to the increase in clearance of circulating triglycerides and hepatic uptake of fatty acids without affecting hepatic de novo lipogenesis, very low-density lipoprotein secretion, or intestinal lipid absorption. Our study highlights the potential of PLA2G12A gene therapy as a promising approach for treating obesity, insulin resistance and T2DM.


Subject(s)
Diet, High-Fat , Energy Metabolism , Insulin Resistance , Mice, Inbred C57BL , Obesity , Triglycerides , Animals , Obesity/metabolism , Obesity/etiology , Mice , Triglycerides/metabolism , Triglycerides/blood , Male , Diet, High-Fat/adverse effects , Humans , Liver/metabolism , Lipid Metabolism
14.
FASEB J ; 38(3): e23472, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38329323

ABSTRACT

Allergic asthma development and pathogenesis are influenced by airway epithelial cells in response to allergens. Heme oxygenase-1 (HO-1), an inducible enzyme responsible for the breakdown of heme, has been considered an appealing target for the treatment of chronic inflammatory diseases. Herein, we report that alleviation of allergic airway inflammation by HO-1-mediated suppression of pyroptosis in airway epithelial cells (AECs). Using house dust mite (HDM)-induced asthma models of mice, we found increased gasdermin D (GSDMD) in the airway epithelium. In vivo administration of disulfiram, a specific inhibitor of pore formation by GSDMD, decreased thymic stromal lymphopoietin (TSLP) release, T helper type 2 immune response, alleviated airway inflammation, and reduced airway hyperresponsiveness (AHR). HO-1 induction by hemin administration reversed these phenotypes. In vitro studies revealed that HO-1 restrained GSDMD-mediated pyroptosis and cytokine TSLP release in AECs by binding Nuclear Factor-Kappa B (NF-κB) p65 RHD domain and thus controlling NF-κB-dependent pyroptosis. These data provide new therapeutic indications for purposing HO-1 to counteract inflammation, which contributes to allergic inflammation control.


Subject(s)
Asthma , Heme Oxygenase-1 , NF-kappa B , Animals , Mice , Cytokines/metabolism , Epithelial Cells/metabolism , Heme Oxygenase-1/metabolism , Inflammation/metabolism , NF-kappa B/metabolism , Pyroptosis , Thymic Stromal Lymphopoietin
15.
J Pathol ; 262(4): 427-440, 2024 04.
Article in English | MEDLINE | ID: mdl-38229567

ABSTRACT

Radiotherapy is one of the standard therapeutic regimens for medulloblastoma (MB). Tumor cells utilize DNA damage repair (DDR) mechanisms to survive and develop resistance during radiotherapy. It has been found that targeting DDR sensitizes tumor cells to radiotherapy in several types of cancer, but whether and how DDR pathways are involved in the MB radiotherapy response remain to be determined. Single-cell RNA sequencing was carried out on 38 MB tissues, followed by expression enrichment assays. Fanconi anemia group D2 gene (FANCD2) expression was evaluated in MB samples and public MB databases. The function of FANCD2 in MB cells was examined using cell counting assays (CCK-8), clone formation, lactate dehydrogenase activity, and in mouse orthotopic models. The FANCD2-related signaling pathway was investigated using assays of peroxidation, a malondialdehyde assay, a reduced glutathione assay, and using FerroOrange to assess intracellular iron ions (Fe2+ ). Here, we report that FANCD2 was highly expressed in the malignant sonic hedgehog (SHH) MB subtype (SHH-MB). FANCD2 played an oncogenic role and predicted worse prognosis in SHH-MB patients. Moreover, FANCD2 knockdown markedly suppressed viability, mobility, and growth of SHH-MB cells and sensitized SHH-MB cells to irradiation. Mechanistically, FANCD2 deficiency led to an accumulation of Fe2+ due to increased divalent metal transporter 1 expression and impaired glutathione peroxidase 4 activity, which further activated ferroptosis and reduced proliferation of SHH-MB cells. Using an orthotopic mouse model, we observed that radiotherapy combined with silencing FANCD2 significantly inhibited the growth of SHH-MB cell-derived tumors in vivo. Our study revealed FANCD2 as a potential therapeutic target in SHH-MB and silencing FANCD2 could sensitize SHH-MB cells to radiotherapy via inducing ferroptosis. © 2024 The Pathological Society of Great Britain and Ireland.


Subject(s)
Cerebellar Neoplasms , Fanconi Anemia , Ferroptosis , Medulloblastoma , Mice , Animals , Humans , Medulloblastoma/genetics , Medulloblastoma/radiotherapy , Ferroptosis/genetics , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Cerebellar Neoplasms/genetics , Cerebellar Neoplasms/radiotherapy , Cell Line, Tumor , Fanconi Anemia Complementation Group D2 Protein/genetics
16.
J Immunol ; 210(2): 180-190, 2023 01 15.
Article in English | MEDLINE | ID: mdl-36458991

ABSTRACT

Acute pancreatitis (AP) can be complicated by inflammatory disorders of remote organs, such as lung injury, in which Jumonji domain-containing protein 3 (JMJD3) plays a vital role in proinflammatory responses. Currently, we found that JMJD3 expression was upregulated in the pancreas and lung in an AP male mouse model, which was also confirmed in AP patients. Further experiments revealed that the upregulation of JMJD3 and proinflammatory effects were possibly exerted by mitochondrial DNA (mtDNA) or oxidized-mtDNA from tissue injury caused by AP. The release of mtDNA and oxidized-mtDNA contributed to the infiltration of inflammatory monocytes in lung injury through the stimulator of IFN genes (STING)/TLR9-NF-κB-JMJD3-TNF-α pathway. The inhibition of JMJD3 or utilization of Jmjd3-cKO mice significantly alleviated pulmonary inflammation induced by AP. Blocking mtDNA oxidation or knocking down the TLR9/STING pathway effectively alleviated inflammation. Therefore, inhibition of JMJD3 or STING/TLR9 pathway blockage might be a potential therapeutic strategy to treat AP and the associated lung injury.


Subject(s)
Lung Injury , Pancreatitis , Male , Mice , Animals , Toll-Like Receptor 9/metabolism , Acute Disease , NF-kappa B/metabolism , DNA, Mitochondrial/genetics , DNA, Mitochondrial/metabolism
17.
Nucleic Acids Res ; 51(3): 1050-1066, 2023 02 22.
Article in English | MEDLINE | ID: mdl-36660824

ABSTRACT

While linear ubiquitin plays critical roles in multiple cell signaling pathways, few substrates have been identified. Global profiling of linear ubiquitin substrates represents a significant challenge because of the low endogenous level of linear ubiquitination and the background interference arising from highly abundant ubiquitin linkages (e.g. K48- and K63-) and from the non-specific attachment of interfering proteins to the linear polyubiquitin chain. We developed a bio-orthogonal linear ubiquitin probe by site-specific encoding of a norbornene amino acid on ubiquitin (NAEK-Ub). This probe facilitates covalent labeling of linear ubiquitin substrates in live cells and enables selective enrichment and identification of linear ubiquitin-modified proteins. Given the fact that the frequent overexpression of the linear linkage-specific deubiquitinase OTULIN correlates with poor prognosis in glioblastoma, we demonstrated the feasibility of the NAEK-Ub strategy by identifying and validating substrates of linear ubiquitination in patient-derived glioblastoma stem-like cells (GSCs). We identified STAT3 as a bona fide substrate of linear ubiquitin, and showed that linear ubiquitination negatively regulates STAT3 activity by recruitment of the phosphatase TC-PTP to STAT3. Furthermore, we demonstrated that preferential expression of OTULIN in GSCs restricts linear ubiquitination on STAT3 and drives persistent STAT3 signaling, and thereby maintains the stemness and self-renewal of GSCs.


Subject(s)
Glioblastoma , STAT3 Transcription Factor , Ubiquitin , Humans , Polyubiquitin/genetics , Signal Transduction , STAT3 Transcription Factor/metabolism , Ubiquitin/metabolism , Ubiquitination
18.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Article in English | MEDLINE | ID: mdl-34969844

ABSTRACT

Deoxypodophyllotoxin contains a core of four fused rings (A to D) with three consecutive chiral centers, the last being created by the attachment of a peripheral trimethoxyphenyl ring (E) to ring C. Previous studies have suggested that the iron(II)- and 2-oxoglutarate-dependent (Fe/2OG) oxygenase, deoxypodophyllotoxin synthase (DPS), catalyzes the oxidative coupling of ring B and ring E to form ring C and complete the tetracyclic core. Despite recent efforts to deploy DPS in the preparation of deoxypodophyllotoxin analogs, the mechanism underlying the regio- and stereoselectivity of this cyclization event has not been elucidated. Herein, we report 1) two structures of DPS in complex with 2OG and (±)-yatein, 2) in vitro analysis of enzymatic reactivity with substrate analogs, and 3) model reactions addressing DPS's catalytic mechanism. The results disfavor a prior proposal of on-pathway benzylic hydroxylation. Rather, the DPS-catalyzed cyclization likely proceeds by hydrogen atom abstraction from C7', oxidation of the benzylic radical to a carbocation, Friedel-Crafts-like ring closure, and rearomatization of ring B by C6 deprotonation. This mechanism adds to the known pathways for transformation of the carbon-centered radical in Fe/2OG enzymes and suggests what types of substrate modification are likely tolerable in DPS-catalyzed production of deoxypodophyllotoxin analogs.


Subject(s)
Berberidaceae/enzymology , Drugs, Chinese Herbal/chemistry , Ligases/chemistry , Plant Proteins/chemistry , Podophyllotoxin/analogs & derivatives , Oxidation-Reduction , Podophyllotoxin/chemistry
19.
Diabetologia ; 67(5): 850-863, 2024 May.
Article in English | MEDLINE | ID: mdl-38413438

ABSTRACT

AIMS/HYPOTHESIS: Type 2 diabetes mellitus is known to contribute to the development of heart failure with preserved ejection fraction (HFpEF). However, identifying HFpEF in individuals with type 2 diabetes early on is often challenging due to a limited array of biomarkers. This study aims to investigate specific biomarkers associated with the progression of HFpEF in individuals with type 2 diabetes, for the purpose of enabling early detection and more effective management strategies. METHODS: Blood samples were collected from individuals with type 2 diabetes, both with and without HFpEF, for proteomic analysis. Plasma integrin α1 (ITGA1) levels were measured and compared between the two groups. Participants were further categorised based on ITGA1 levels and underwent detailed transthoracic echocardiography at baseline and during a median follow-up period of 30 months. Multivariable linear and Cox regression analyses were conducted separately to assess the associations between plasma ITGA1 levels and changes in echocardiography indicators and re-hospitalisation risk. Additionally, proteomic data for the individuals' left ventricles, from ProteomeXchange database, were analysed to uncover mechanisms underlying the change in ITGA1 levels in HFpEF. RESULTS: Individuals with type 2 diabetes and HFpEF showed significantly higher plasma ITGA1 levels than the individuals with type 2 diabetes without HFpEF. These elevated ITGA1 levels were associated with left ventricular remodelling and impaired diastolic function. Furthermore, during a median follow-up of 30 months, multivariable analysis revealed that elevated ITGA1 levels independently correlated with deterioration of both diastolic and systolic cardiac functions. Additionally, higher baseline plasma ITGA1 levels independently predicted re-hospitalisation risk (HR 2.331 [95% CI 1.387, 3.917], p=0.001). Proteomic analysis of left ventricular myocardial tissue provided insights into the impact of increased ITGA1 levels on cardiac fibrosis-related pathways and the contribution made by these changes to the development and progression of HFpEF. CONCLUSIONS/INTERPRETATION: ITGA1 serves as a biomarker for monitoring cardiac structural and functional damage, can be used to accurately diagnose the presence of HFpEF, and can be used to predict potential deterioration in cardiac structure and function as well as re-hospitalisation for individuals with type 2 diabetes. Its measurement holds promise for facilitating risk stratification and early intervention to mitigate the adverse cardiovascular effects associated with diabetes. DATA AVAILABILITY: The proteomic data of left ventricular myocardial tissue from individuals with type 2 diabetes, encompassing both those with and without HFpEF, is available from the ProteomeXchange database at http://proteomecentral.proteomexchange.org .


Subject(s)
Diabetes Mellitus, Type 2 , Heart Failure , Humans , Heart Failure/complications , Ventricular Function, Left , Stroke Volume , Integrin alpha1 , Diabetes Mellitus, Type 2/complications , Proteomics , Biomarkers
20.
Carcinogenesis ; 45(3): 170-180, 2024 03 11.
Article in English | MEDLINE | ID: mdl-38195111

ABSTRACT

Approximately 50% of colorectal cancer (CRC) patients would develop metastasis with poor prognosis, therefore, it is necessary to effectively predict metastasis in clinical treatment. In this study, we aimed to establish a machine-learning model for predicting metastasis in CRC patients by considering radiomics and transcriptomics simultaneously. Here, 1023 patients with CRC from three centers were collected and divided into five queues (Dazhou Central Hospital n = 517, Nanchong Central Hospital n = 120 and the Cancer Genome Atlas (TCGA) n = 386). A total of 854 radiomics features were extracted from tumor lesions on CT images, and 217 differentially expressed genes were obtained from non-metastasis and metastasis tumor tissues using RNA sequencing. Based on radiotranscriptomic (RT) analysis, a novel RT model was developed and verified through genetic algorithms (GA). Interleukin (IL)-26, a biomarker in RT model, was verified for its biological function in CRC metastasis. Furthermore, 15 radiomics variables were screened through stepwise regression, which was highly correlated with the IL26 expression level. Finally, a radiomics model (RA) was established by combining GA and stepwise regression analysis with radiomics features. The RA model exhibited favorable discriminatory ability and accuracy for metastasis prediction in two independent verification cohorts. We designed multicenter, multi-scale cohorts to construct and verify novel combined radiomics and genomics models for predicting metastasis in CRC. Overall, RT model and RA model might help clinicians in directing personalized diagnosis and therapeutic regimen selection for patients with CRC.


Subject(s)
Colorectal Neoplasms , Radiomics , Humans , Prognosis , Genomics , Gene Expression , Colorectal Neoplasms/diagnostic imaging , Colorectal Neoplasms/genetics
SELECTION OF CITATIONS
SEARCH DETAIL