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1.
Nat Immunol ; 21(7): 727-735, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32541831

RESUMO

Stimulator-of-interferon genes (STING) is vital for sensing cytosolic DNA and initiating innate immune responses against microbial infection and tumors. Redox homeostasis is the balance of oxidative and reducing reactions present in all living systems. Yet, how the intracellular redox state controls STING activation is unclear. Here, we show that cellular redox homeostasis maintained by glutathione peroxidase 4 (GPX4) is required for STING activation. GPX4 deficiency enhanced cellular lipid peroxidation and thus specifically inhibited the cGAS-STING pathway. Concordantly, GPX4 deficiency inhibited herpes simplex virus-1 (HSV-1)-induced innate antiviral immune responses and promoted HSV-1 replication in vivo. Mechanistically, GPX4 inactivation increased production of lipid peroxidation, which led to STING carbonylation at C88 and inhibited its trafficking from the endoplasmic reticulum (ER) to the Golgi complex. Thus, cellular stress-induced lipid peroxidation specifically attenuates the STING DNA-sensing pathway, suggesting that GPX4 facilitates STING activation by maintaining redox homeostasis of lipids.


Assuntos
Herpes Simples/imunologia , Proteínas de Membrana/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Carbolinas/farmacologia , Células Cultivadas , DNA Viral/imunologia , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Feminino , Fibroblastos , Complexo de Golgi/metabolismo , Células HEK293 , Herpes Simples/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/imunologia , Homeostase/imunologia , Humanos , Imunidade Inata , Peroxidação de Lipídeos/genética , Peroxidação de Lipídeos/imunologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Proteínas de Membrana/imunologia , Camundongos , Camundongos Knockout , Nucleotidiltransferases/metabolismo , Oxirredução , Oximas/farmacologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/antagonistas & inibidores , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Cultura Primária de Células , Carbonilação Proteica/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Sulfonamidas/farmacologia , Células THP-1 , Replicação Viral/imunologia
2.
Genome Res ; 34(5): 740-756, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38744529

RESUMO

Although DNA N 6-adenine methylation (6mA) is best known in prokaryotes, its presence in eukaryotes has recently generated great interest. Biochemical and genetic evidence supports that AMT1, an MT-A70 family methyltransferase (MTase), is crucial for 6mA deposition in unicellular eukaryotes. Nonetheless, the 6mA transmission mechanism remains to be elucidated. Taking advantage of single-molecule real-time circular consensus sequencing (SMRT CCS), here we provide definitive evidence for semiconservative transmission of 6mA in Tetrahymena thermophila In wild-type (WT) cells, 6mA occurs at the self-complementary ApT dinucleotide, mostly in full methylation (full-6mApT); after DNA replication, hemi-methylation (hemi-6mApT) is transiently present on the parental strand, opposite to the daughter strand readily labeled by 5-bromo-2'-deoxyuridine (BrdU). In ΔAMT1 cells, 6mA predominantly occurs as hemi-6mApT. Hemi-to-full conversion in WT cells is fast, robust, and processive, whereas de novo methylation in ΔAMT1 cells is slow and sporadic. In Tetrahymena, regularly spaced 6mA clusters coincide with the linker DNA of nucleosomes arrayed in the gene body. Importantly, in vitro methylation of human chromatin by the reconstituted AMT1 complex recapitulates preferential targeting of hemi-6mApT sites in linker DNA, supporting AMT1's intrinsic and autonomous role in maintenance methylation. We conclude that 6mA is transmitted by a semiconservative mechanism: full-6mApT is split by DNA replication into hemi-6mApT, which is restored to full-6mApT by AMT1-dependent maintenance methylation. Our study dissects AMT1-dependent maintenance methylation and AMT1-independent de novo methylation, reveals a 6mA transmission pathway with a striking similarity to 5-methylcytosine (5mC) transmission at the CpG dinucleotide, and establishes 6mA as a bona fide eukaryotic epigenetic mark.


Assuntos
Adenina , Metilação de DNA , Tetrahymena thermophila , Tetrahymena thermophila/genética , Tetrahymena thermophila/metabolismo , Adenina/metabolismo , Adenina/análogos & derivados , Replicação do DNA , DNA de Protozoário/genética , DNA de Protozoário/metabolismo
3.
Nature ; 598(7881): 521-525, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34526719

RESUMO

Hepatitis C virus (HCV) infection is a causal agent of chronic liver disease, cirrhosis and hepatocellular carcinoma in humans, and afflicts more than 70 million people worldwide. The HCV envelope glycoproteins E1 and E2 are responsible for the binding of the virus to the host cell, but the exact entry process remains undetermined1. The majority of broadly neutralizing antibodies block interaction between HCV E2 and the large extracellular loop (LEL) of the cellular receptor CD81 (CD81-LEL)2. Here we show that low pH enhances the binding of CD81-LEL to E2, and we determine the crystal structure of E2 in complex with an antigen-binding fragment (2A12) and CD81-LEL (E2-2A12-CD81-LEL); E2 in complex with 2A12 (E2-2A12); and CD81-LEL alone. After binding CD81, residues 418-422 in E2 are displaced, which allows for the extension of an internal loop consisting of residues 520-539. Docking of the E2-CD81-LEL complex onto a membrane-embedded, full-length CD81 places the residues Tyr529 and Trp531 of E2 proximal to the membrane. Liposome flotation assays show that low pH and CD81-LEL increase the interaction of E2 with membranes, whereas structure-based mutants of Tyr529, Trp531 and Ile422 in the amino terminus of E2 abolish membrane binding. These data support a model in which acidification and receptor binding result in a conformational change in E2 in preparation for membrane fusion.


Assuntos
Hepacivirus/metabolismo , Ligação Proteica , Receptores Virais/química , Receptores Virais/metabolismo , Tetraspanina 28/química , Tetraspanina 28/metabolismo , Internalização do Vírus , Animais , Anticorpos Neutralizantes/imunologia , Membrana Celular/química , Membrana Celular/metabolismo , Células HEK293 , Hepacivirus/química , Hepacivirus/genética , Humanos , Leontopithecus , Fusão de Membrana , Modelos Moleculares , Receptores Virais/imunologia , Tetraspanina 28/imunologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(34): e2120771120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579137

RESUMO

The binding of tumor necrosis factor-like cytokine 1A (TL1A) to death receptor 3 (DR3) plays an important role in the interaction between dendritic cells (DCs) and T cells and contributes to intestinal inflammation development. However, the mechanism by which DCs expressing TL1A mediate helper T (Th) cell differentiation in the intestinal lamina propria (LP) during the pathogenesis of inflammatory bowel disease remains unclear. In this study, we found that TL1A/DR3 promoted Th1 and Th17 cell differentiation in T-T and DC-T cell interaction-dependent manners. TL1A-deficient CD4+ T cells failed to polarize into Th1/Th17 cells and did not cause colonic inflammation in a T cell transfer colitis model. Notably, TL1A was located in the cytoplasm and nuclei of DCs, positively regulated the DC-specific ICAM-grabbing nonintegrin/RAF1/nuclear factor κB signaling pathway, enhanced the antigen uptake ability of DCs, and promoted TLR4-mediated DC activation, inducing naive CD4+ T cell differentiation into Th1 and Th17 cells. Our work reveals that TL1A plays a regulatory role in inflammatory bowel disease pathogenesis.


Assuntos
Doenças Inflamatórias Intestinais , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Humanos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Inflamação/metabolismo , Fator de Necrose Tumoral alfa
5.
Proc Natl Acad Sci U S A ; 120(21): e2221116120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37192158

RESUMO

Alternative splicing (AS) is prevalent in cancer, generating an extensive but largely unexplored repertoire of novel immunotherapy targets. We describe Isoform peptides from RNA splicing for Immunotherapy target Screening (IRIS), a computational platform capable of discovering AS-derived tumor antigens (TAs) for T cell receptor (TCR) and chimeric antigen receptor T cell (CAR-T) therapies. IRIS leverages large-scale tumor and normal transcriptome data and incorporates multiple screening approaches to discover AS-derived TAs with tumor-associated or tumor-specific expression. In a proof-of-concept analysis integrating transcriptomics and immunopeptidomics data, we showed that hundreds of IRIS-predicted TCR targets are presented by human leukocyte antigen (HLA) molecules. We applied IRIS to RNA-seq data of neuroendocrine prostate cancer (NEPC). From 2,939 NEPC-associated AS events, IRIS predicted 1,651 epitopes from 808 events as potential TCR targets for two common HLA types (A*02:01 and A*03:01). A more stringent screening test prioritized 48 epitopes from 20 events with "neoantigen-like" NEPC-specific expression. Predicted epitopes are often encoded by microexons of ≤30 nucleotides. To validate the immunogenicity and T cell recognition of IRIS-predicted TCR epitopes, we performed in vitro T cell priming in combination with single-cell TCR sequencing. Seven TCRs transduced into human peripheral blood mononuclear cells (PBMCs) showed high activity against individual IRIS-predicted epitopes, providing strong evidence of isolated TCRs reactive to AS-derived peptides. One selected TCR showed efficient cytotoxicity against target cells expressing the target peptide. Our study illustrates the contribution of AS to the TA repertoire of cancer cells and demonstrates the utility of IRIS for discovering AS-derived TAs and expanding cancer immunotherapies.


Assuntos
Neoplasias , Precursores de RNA , Masculino , Humanos , Precursores de RNA/metabolismo , Processamento Alternativo , Leucócitos Mononucleares/metabolismo , Receptores de Antígenos de Linfócitos T , Epitopos de Linfócito T , Imunoterapia , Antígenos de Neoplasias , Peptídeos/metabolismo , Neoplasias/genética , Neoplasias/terapia
6.
J Biol Chem ; 300(3): 105699, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301891

RESUMO

DEC205 (CD205) is one of the major endocytic receptors on dendritic cells and has been widely used as a receptor target in immune therapies. It has been shown that DEC205 can recognize dead cells through keratins in a pH-dependent manner. However, the mechanism underlying the interaction between DEC205 and keratins remains unclear. Here we determine the crystal structures of an N-terminal fragment of human DEC205 (CysR∼CTLD3). The structural data show that DEC205 shares similar overall features with the other mannose receptor family members such as the mannose receptor and Endo180, but the individual domains of DEC205 in the crystal structure exhibit distinct structural features that may lead to specific ligand binding properties of the molecule. Among them, CTLD3 of DEC205 adopts a unique fold of CTLD, which may correlate with the binding of keratins. Furthermore, we examine the interaction of DEC205 with keratins by mutagenesis and biochemical assays based on the structural information and identify an XGGGX motif on keratins that can be recognized by DEC205, thereby providing insights into the interaction between DEC205 and keratins. Overall, these findings not only improve the understanding of the diverse ligand specificities of the mannose receptor family members at the molecular level but may also give clues for the interactions of keratins with their binding partners in the corresponding pathways.


Assuntos
Queratinas , Lectinas Tipo C , Modelos Moleculares , Humanos , Células Dendríticas/metabolismo , Lectinas Tipo C/química , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Ligantes , Receptor de Manose/química , Mutagênese , Ligação Proteica , Dobramento de Proteína , Estrutura Terciária de Proteína , Domínios e Motivos de Interação entre Proteínas , Cristalografia por Raios X
7.
Lancet ; 403(10430): 924-934, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38330980

RESUMO

BACKGROUND: Introduced in 1992, intracytoplasmic sperm injection (ICSI) was initially indicated for severe male infertility; however, its use has since been expanded to non-severe male infertility. We aimed to compare the efficacy and safety of ICSI versus conventional in-vitro fertilisation (IVF) in couples with infertility with non-severe male factor. METHODS: We conducted an investigator-initiated, multicentre, open-label, randomised controlled trial in ten reproductive medicine centres across China. Couples with infertility with non-severe male factor without a history of poor fertilisation were randomly assigned (1:1) to undergo either ICSI or conventional IVF. The primary outcome was live birth after first embryo transfer. We performed the primary analysis in the intention-to-treat population using log-binomial regression models for categorical outcomes or linear regression models for continuous outcomes, adjusting for centre. This trial is registered with Clinicaltrials.gov, NCT03298633, and is completed. FINDINGS: Between April 4, 2018, and Nov 15, 2021, 3879 couples were screened, of whom 2387 (61·5%) couples were randomly assigned (1184 [49·6%] to the ICSI group and 1203 [50·4%] to the conventional IVF group). After excluding couples who were ineligible, randomised twice, or withdrew consent, 1154 (97·5%) in the ICSI group and 1175 (97·7%) in the conventional IVF group were included in the primary analysis. Live birth after first embryo transfer occurred in 390 (33·8%) couples in the ICSI group and in 430 (36·6%) couples in the conventional IVF group (adjusted risk ratio [RR] 0·92 [95% CI 0·83-1·03]; p=0·16). Two (0·2%) neonatal deaths were reported in the ICSI group and one (0·1%) in the conventional IVF group. INTERPRETATION: In couples with infertility with non-severe male factor, ICSI did not improve live birth rate compared with conventional IVF. Given that ICSI is an invasive procedure associated with additional costs and potential increased risks to offspring health, routine use is not recommended in this population. FUNDING: National Natural Science Foundation of China, National Key Research and Development Program, Beijing Municipal Science & Technology Commission, and Peking University Third Hospital.


Assuntos
Infertilidade Masculina , Injeções de Esperma Intracitoplásmicas , Gravidez , Feminino , Recém-Nascido , Masculino , Humanos , Injeções de Esperma Intracitoplásmicas/métodos , Sêmen , Fertilização in vitro/métodos , Infertilidade Masculina/terapia , Fertilização , Taxa de Gravidez
8.
PLoS Pathog ; 19(5): e1011123, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37196033

RESUMO

SARS-CoV Spike (S) protein shares considerable homology with SARS-CoV-2 S, especially in the conserved S2 subunit (S2). S protein mediates coronavirus receptor binding and membrane fusion, and the latter activity can greatly influence coronavirus infection. We observed that SARS-CoV S is less effective in inducing membrane fusion compared with SARS-CoV-2 S. We identify that S813T mutation is sufficient in S2 interfering with the cleavage of SARS-CoV-2 S by TMPRSS2, reducing spike fusogenicity and pseudoparticle entry. Conversely, the mutation of T813S in SARS-CoV S increased fusion ability and viral replication. Our data suggested that residue 813 in the S was critical for the proteolytic activation, and the change from threonine to serine at 813 position might be an evolutionary feature adopted by SARS-2-related viruses. This finding deepened the understanding of Spike fusogenicity and could provide a new perspective for exploring Sarbecovirus' evolution.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteólise , Replicação Viral , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
9.
FASEB J ; 38(7): e23597, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581235

RESUMO

Sepsis is a life-threatening condition that occurs when the body responds to an infection but subsequently triggers widespread inflammation and impaired blood flow. These pathologic responses can rapidly cause multiple organ dysfunction or failure either one by one or simultaneously. The fundamental common mechanisms involved in sepsis-induced multiple organ dysfunction remain unclear. Here, employing quantitative global and phosphoproteomics, we examine the liver's temporal proteome and phosphoproteome changes after moderate sepsis induced by cecum ligation and puncture. In total, 4593 global proteins and 1186 phosphoproteins according to 3275 phosphosites were identified. To characterize the liver-kidney comorbidity after sepsis, we developed a mathematical model and performed cross-analyses of liver and kidney proteome data obtained from the same set of mice. Beyond immune response, we showed the commonly disturbed pathways and key regulators of the liver-kidney comorbidity are linked to energy metabolism and consumption. Our data provide open resources to understand the communication between the liver and kidney as they work to fight infection and maintain homeostasis.


Assuntos
Proteoma , Sepse , Camundongos , Animais , Insuficiência de Múltiplos Órgãos/complicações , Insuficiência de Múltiplos Órgãos/patologia , Fígado/metabolismo , Rim/metabolismo , Sepse/metabolismo , Modelos Animais de Doenças
10.
Mol Psychiatry ; 29(2): 484-495, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38102486

RESUMO

Parent-child transmission of suicidal behaviors has been extensively studied, but the investigation of a three-generation family suicide risk paradigm remains limited. In this study, we aimed to explore the behavioral and brain signatures of multi-generational family history of suicidal behaviors (FHoS) in preadolescents, utilizing a longitudinal design and the dataset from Adolescent Brain and Cognitive DevelopmentSM Study (ABCD Study®), which comprised 4 years of data and includes a total of 9,653 preadolescents. Our findings revealed that multi-generational FHoS was significantly associated with an increased risk of problematic behaviors and suicidal behaviors (suicide ideation and suicide attempt) in offspring. Interestingly, the problematic behaviors were further identified as a mediator in the multi-generational transmission of suicidal behaviors. Additionally, we observed alterations in brain structure within superior temporal gyrus (STG), precentral/postcentral cortex, posterior parietal cortex (PPC), cingulate cortex (CC), and planum temporale (PT), as well as disrupted functional connectivity of default mode network (DMN), ventral attention network (VAN), dorsal attention network (DAN), fronto-parietal network (FPN), and cingulo-opercular network (CON) among preadolescents with FHoS. These results provide compelling longitudinal evidence at the population level, highlighting the associations between multi-generational FHoS and maladaptive behavioral and neurodevelopmental outcomes in offspring. These findings underscore the need for early preventive measures aimed at mitigating the familial transmission of suicide risk and reducing the global burden of deaths among children and adolescents.


Assuntos
Encéfalo , Ideação Suicida , Tentativa de Suicídio , Humanos , Feminino , Masculino , Criança , Adolescente , Tentativa de Suicídio/psicologia , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Suicídio/psicologia , Fatores de Risco
11.
Proc Natl Acad Sci U S A ; 119(33): e2122716119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35960843

RESUMO

The microenvironment of malignant melanomas defines the properties of tumor blood vessels and regulates infiltration and vascular dissemination of immune and cancer cells, respectively. Previous research in other cancer entities suggested the complement system as an essential part of the tumor microenvironment. Here, we confirm activation of the complement system in samples of melanoma patients and murine melanomas. We identified the tumor endothelium as the starting point of the complement cascade. Generation of complement-derived C5a promoted the recruitment of neutrophils. Upon contact with the vascular endothelium, neutrophils were further activated by complement membrane attack complexes (MACs). MAC-activated neutrophils release neutrophil extracellular traps (NETs). Close to the blood vessel wall, NETs opened the endothelial barrier as indicated by an enhanced vascular leakage. This facilitated the entrance of melanoma cells into the circulation and their systemic spread. Depletion of neutrophils or lack of MAC formation in complement component 6 (C6)-deficient animals protected the vascular endothelium and prevented vascular intravasation of melanoma cells. Our data suggest that inhibition of MAC-mediated neutrophil activation is a potent strategy to abolish hematogenous dissemination in melanoma.


Assuntos
Complexo de Ataque à Membrana do Sistema Complemento , Endotélio Vascular , Armadilhas Extracelulares , Melanoma , Neutrófilos , Microambiente Tumoral , Animais , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Proteínas do Sistema Complemento , Endotélio Vascular/fisiopatologia , Humanos , Melanoma/irrigação sanguínea , Melanoma/imunologia , Melanoma/patologia , Camundongos , Neutrófilos/imunologia , Permeabilidade
12.
Proc Natl Acad Sci U S A ; 119(39): e2208496119, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36122204

RESUMO

Allotetraploid cotton (Gossypium) species represents a model system for the study of plant polyploidy, molecular evolution, and domestication. Here, chromosome-scale genome sequences were obtained and assembled for two recently described wild species of tetraploid cotton, Gossypium ekmanianum [(AD)6, Ge] and Gossypium stephensii [(AD)7, Gs], and one early form of domesticated Gossypium hirsutum, race punctatum [(AD)1, Ghp]. Based on phylogenomic analysis, we provide a dated whole-genome level perspective for the evolution of the tetraploid Gossypium clade and resolved the evolutionary relationships of Gs, Ge, and domesticated G. hirsutum. We describe genomic structural variation that arose during Gossypium evolution and describe its correlates-including phenotypic differentiation, genetic isolation, and genetic convergence-that contributed to cotton biodiversity and cotton domestication. Presence/absence variation is prominent in causing cotton genomic structural variations. A presence/absence variation-derived gene encoding a phosphopeptide-binding protein is implicated in increasing fiber length during cotton domestication. The relatively unimproved Ghp offers the potential for gene discovery related to adaptation to environmental challenges. Expanded gene families enoyl-CoA δ isomerase 3 and RAP2-7 may have contributed to abiotic stress tolerance, possibly by targeting plant hormone-associated biochemical pathways. Our results generate a genomic context for a better understanding of cotton evolution and for agriculture.


Assuntos
Evolução Molecular , Genoma de Planta , Gossypium , Fibra de Algodão , Variação Genética/genética , Genoma de Planta/genética , Gossypium/classificação , Gossypium/genética , Isomerases/genética , Isomerases/metabolismo , Tetraploidia
13.
Clin Microbiol Rev ; 36(1): e0004022, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36645300

RESUMO

Preventing and controlling influenza virus infection remains a global public health challenge, as it causes seasonal epidemics to unexpected pandemics. These infections are responsible for high morbidity, mortality, and substantial economic impact. Vaccines are the prophylaxis mainstay in the fight against influenza. However, vaccination fails to confer complete protection due to inadequate vaccination coverages, vaccine shortages, and mismatches with circulating strains. Antivirals represent an important prophylactic and therapeutic measure to reduce influenza-associated morbidity and mortality, particularly in high-risk populations. Here, we review current FDA-approved influenza antivirals with their mechanisms of action, and different viral- and host-directed influenza antiviral approaches, including immunomodulatory interventions in clinical development. Furthermore, we also illustrate the potential utility of machine learning in developing next-generation antivirals against influenza.


Assuntos
Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Orthomyxoviridae , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/prevenção & controle , Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Orthomyxoviridae/tratamento farmacológico , Vacinas contra Influenza/uso terapêutico
14.
Mol Plant Microbe Interact ; 37(4): 416-423, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38171485

RESUMO

Soybean cyst nematode (Heterodera glycines, soybean cyst nematode [SCN]) disease adversely affects the yield of soybean and leads to billions of dollars in losses every year. To control the disease, it is necessary to study the resistance genes of the plant and their mechanisms. Isoflavonoids are secondary metabolites of the phenylalanine pathway, and they are synthesized in soybean. They are essential in plant response to biotic and abiotic stresses. In this study, we reported that phenylalanine ammonia-lyase (PAL) genes GmPALs involved in isoflavonoid biosynthesis, can positively regulate soybean resistance to SCN. Our previous study demonstrated that the expression of GmPAL genes in the resistant cultivar Huipizhi (HPZ) heidou are strongly induced by SCN. PAL is the rate-limiting enzyme that catalyzes the first step of phenylpropanoid metabolism, and it responds to biotic or abiotic stresses. Here, we demonstrate that the resistance of soybeans against SCN is suppressed by PAL inhibitor l-α-(aminooxy)-ß-phenylpropionic acid (L-AOPP) treatment. Overexpression of eight GmPAL genes caused diapause of nematodes in transgenic roots. In a petiole-feeding bioassay, we identified that two isoflavones, daidzein and genistein, could enhance resistance against SCN and suppress nematode development. This study thus reveals GmPAL-mediated resistance against SCN, information that has good application potential. The role of isoflavones in soybean resistance provides new information for the control of SCN. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Resistência à Doença , Regulação da Expressão Gênica de Plantas , Glycine max , Isoflavonas , Fenilalanina Amônia-Liase , Doenças das Plantas , Tylenchoidea , Glycine max/genética , Glycine max/parasitologia , Tylenchoidea/fisiologia , Doenças das Plantas/parasitologia , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Animais , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Resistência à Doença/genética , Isoflavonas/farmacologia , Isoflavonas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas
15.
Neuroimage ; 294: 120645, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38734156

RESUMO

Aggressive adolescents tend to exhibit abnormal fear acquisition and extinction, and reactive aggressive adolescents are often more anxious. However, the relationship between fear generalization and reactive aggression (RA) remains unknown. According to Reactive-Proactive Aggression Questionnaire (RPQ) scores, 61 adolescents were divided into two groups, namely, a high RA group (N = 30) and a low aggression (LA) group (N = 31). All participants underwent three consecutive phases of the Pavlovian conditioning paradigm (i.e., habituation, acquisition, and generalization), and neural activation of the medial prefrontal cortex (mPFC) was assessed by functional near-infrared spectroscopy (fNIRS). The stimuli were ten circles with varying sizes, including two conditioned stimuli (CSs) and eight generalization stimuli (GSs). A scream at 85 dB served as the auditory unconditioned stimulus (US). The US expectancy ratings of both CSs and GSs were higher in the RA group than in the LA group. The fNIRS results showed that CSs and GSs evoked lower mPFC activation in the RA group compared to the LA group during fear generalization. These findings suggest that abnormalities in fear acquisition and generalization are prototypical dysregulations in adolescents with RA. They provide neurocognitive evidence for dysregulated fear learning in the mechanisms underlying adolescents with RA, highlighting the need to develop emotional regulation interventions for these individuals.


Assuntos
Agressão , Condicionamento Clássico , Medo , Generalização Psicológica , Córtex Pré-Frontal , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Adolescente , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Medo/fisiologia , Masculino , Feminino , Condicionamento Clássico/fisiologia , Generalização Psicológica/fisiologia , Agressão/fisiologia
16.
J Am Chem Soc ; 146(8): 5445-5454, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38304982

RESUMO

Ion exchange is an effective postsynthesis strategy for the design of colloidal nanomaterials with unique structures and properties. In contrast to the rapid development of cation exchange (CE), the study of anion exchange is still in its infancy and requires an in-depth understanding. Magic-size clusters (MSCs) are important reaction intermediates in quantum dot (QD) synthesis, and studying the ion exchange processes can provide valuable insights into the transformations of QDs. Here, we achieved anion exchange in Cd-based MSCs and elucidated the reaction pathways. We demonstrated that the anion exchange was a stepwise intermolecular transition mediated by covalent inorganic complexes (CICs). We proposed that this transition involved three essential steps: the disassembly of CdE1-MSCs into CdE1-CICs (step 1), an anion exchange reaction from CdE1-CICs to CdE2-CICs (step 2), and assembly of CdE2-CICs to CdE2-MSCs (step 3). Step 3 was the rate-determining step and followed first-order reaction kinetics (kobs = 0.01 min-1; from CdSe-MSCs to CdS-MSCs). Further studies revealed that the activity of foreign anions only affected the reaction kinetics without altering the reaction pathway. The present study provides a deeper insight into the anion exchange mechanisms of MSCs and will further shed light on the synthesis of QDs.

17.
J Am Chem Soc ; 146(12): 8768-8779, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38483318

RESUMO

2'-Deoxynucleosides and analogues play a vital role in drug development, but their preparation remains a significant challenge. Previous studies have focused on ß-2'-deoxynucleosides with the natural ß-configuration. In fact, their isomeric α-2'-deoxynucleosides also exhibit diverse bioactivities and even better metabolic stability. Herein, we report that both α- and ß-2'-deoxynucleosides can be prepared with high yields and stereoselectivity using a remote directing diphenylphosphinoyl (DPP) group. It is particularly efficient to prepare α-2'-deoxynucleosides with an easily accessible 3,5-di-ODPP donor. Instead of acting as a H-bond acceptor on a 2-(diphenylphosphinoyl)acetyl (DPPA) group in our previous studies for syn-facial O-glycosylation, the phosphine oxide moiety here acts as a remote participating group to enable highly antifacial N-glycosylation. This proposed remote participation mechanism is supported by our first characterization of an important 1,5-briged P-heterobicyclic intermediate via variable-temperature NMR spectroscopy. Interestingly, antiproliferative assays led to a α-2'-deoxynucleoside with IC50 values in the low micromole range against central nervous system tumor cell lines SH-SY5Y and LN229, whereas its ß-anomer exhibited no inhibition at 100 µM. Furthermore, the DPP group significantly enhanced the antitumor activities by 10 times.


Assuntos
Neuroblastoma , Fosfinas , Humanos , Glicosilação
18.
Breast Cancer Res ; 26(1): 48, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504374

RESUMO

BACKGROUND: Breast cancer stem cell (CSC) expansion results in tumor progression and chemoresistance; however, the modulation of CSC pluripotency remains unexplored. Transmembrane protein 120B (TMEM120B) is a newly discovered protein expressed in human tissues, especially in malignant tissues; however, its role in CSC expansion has not been studied. This study aimed to determine the role of TMEM120B in transcriptional coactivator with PDZ-binding motif (TAZ)-mediated CSC expansion and chemotherapy resistance. METHODS: Both bioinformatics analysis and immunohistochemistry assays were performed to examine expression patterns of TMEM120B in lung, breast, gastric, colon, and ovarian cancers. Clinicopathological factors and overall survival were also evaluated. Next, colony formation assay, MTT assay, EdU assay, transwell assay, wound healing assay, flow cytometric analysis, sphere formation assay, western blotting analysis, mouse xenograft model analysis, RNA-sequencing assay, immunofluorescence assay, and reverse transcriptase-polymerase chain reaction were performed to investigate the effect of TMEM120B interaction on proliferation, invasion, stemness, chemotherapy sensitivity, and integrin/FAK/TAZ/mTOR activation. Further, liquid chromatography-tandem mass spectrometry analysis, GST pull-down assay, and immunoprecipitation assays were performed to evaluate the interactions between TMEM120B, myosin heavy chain 9 (MYH9), and CUL9. RESULTS: TMEM120B expression was elevated in lung, breast, gastric, colon, and ovarian cancers. TMEM120B expression positively correlated with advanced TNM stage, lymph node metastasis, and poor prognosis. Overexpression of TMEM120B promoted breast cancer cell proliferation, invasion, and stemness by activating TAZ-mTOR signaling. TMEM120B directly bound to the coil-coil domain of MYH9, which accelerated the assembly of focal adhesions (FAs) and facilitated the translocation of TAZ. Furthermore, TMEM120B stabilized MYH9 by preventing its degradation by CUL9 in a ubiquitin-dependent manner. Overexpression of TMEM120B enhanced resistance to docetaxel and doxorubicin. Conversely, overexpression of TMEM120B-∆CCD delayed the formation of FAs, suppressed TAZ-mTOR signaling, and abrogated chemotherapy resistance. TMEM120B expression was elevated in breast cancer patients with poor treatment outcomes (Miller/Payne grades 1-2) than in those with better outcomes (Miller/Payne grades 3-5). CONCLUSIONS: Our study reveals that TMEM120B bound to and stabilized MYH9 by preventing its degradation. This interaction activated the ß1-integrin/FAK-TAZ-mTOR signaling axis, maintaining stemness and accelerating chemotherapy resistance.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Humanos , Animais , Camundongos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Integrina beta1 , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células , Cadeias Pesadas de Miosina
19.
Neurobiol Dis ; 191: 106402, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184015

RESUMO

Social dominance is a universal phenomenon among grouped animals that profoundly affects survival, health, and reproductive success by determining access to resources, and exerting a powerful influence on subsequent behavior. However, the understanding of pain and anxiety comorbidities in dominant or subordinate animals suffering from chronic pain is not well-defined. Here, we provide evidence that subordinate mice are more susceptible to pain-induced anxiety compared to dominant mice. We propose that the gut microbiota may play a mediating role in this mechanism. Our findings demonstrate that transplantation of fecal microbiota from subordinate mice with chronic inflammatory pain, but not dominant mice, into antibiotics-treated pseudo-germ-free mice significantly amplifies anxiety-like phenotypes, highlighting the critical involvement of gut microbiota in this behavioral response. Using chronic inflammatory pain model, we carried out 16S rRNA sequencing and untargeted metabolomic analyses to explore the relationship between microbiota and metabolites in a stable social hierarchy of mice. Interestingly, anxiety-like behaviors were directly associated with some microbial genera and metabolites, especially bile acid metabolism. Overall, we have demonstrated a close relationship between social status and anxiety susceptibility, highlighting the contributions of gut microbiota and the associated metabolites in the high-anxiety state of subordinate mice with chronic inflammatory pain.


Assuntos
Dor Crônica , Microbioma Gastrointestinal , Camundongos , Animais , Microbioma Gastrointestinal/genética , Depressão , RNA Ribossômico 16S , Hierarquia Social , Ansiedade
20.
Hippocampus ; 34(2): 58-72, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38049972

RESUMO

Numerous epilepsy-related genes have been identified in recent decades by unbiased genome-wide screens. However, the available druggable targets for temporal lobe epilepsy (TLE) remain limited. Furthermore, a substantial pool of candidate genes potentially applicable to TLE therapy awaits further validation. In this study, we reveal the significant role of KCNQ2 and KCNQ3, two M-type potassium channel genes, in the onset of seizures in TLE. Our investigation began with a quantitative analysis of two publicly available TLE patient databases to establish a correlation between seizure onset and the downregulated expression of KCNQ2/3. We then replicated these pathological changes in a pilocarpine seizure mouse model and observed a decrease in spike frequency adaptation due to the affected M-currents in dentate gyrus granule neurons. In addition, we performed a small-scale simulation of the dentate gyrus network and confirmed that the impaired spike frequency adaptation of granule cells facilitated epileptiform activity throughout the network. This, in turn, resulted in prolonged seizure duration and reduced interictal intervals. Our findings shed light on an underlying mechanism contributing to ictogenesis in the TLE hippocampus and suggest a promising target for the development of antiepileptic drugs.


Assuntos
Epilepsia do Lobo Temporal , Camundongos , Animais , Humanos , Epilepsia do Lobo Temporal/patologia , Giro Denteado/metabolismo , Convulsões/induzido quimicamente , Convulsões/patologia , Hipocampo/metabolismo , Neurônios/fisiologia , Canal de Potássio KCNQ2/genética
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