RESUMO
Metabolic reprograming toward aerobic glycolysis is a pivotal mechanism shaping immune responses. Here we show that deficiency in NF-κB-inducing kinase (NIK) impairs glycolysis induction, rendering CD8+ effector T cells hypofunctional in the tumor microenvironment. Conversely, ectopic expression of NIK promotes CD8+ T cell metabolism and effector function, thereby profoundly enhancing antitumor immunity and improving the efficacy of T cell adoptive therapy. NIK regulates T cell metabolism via a NF-κB-independent mechanism that involves stabilization of hexokinase 2 (HK2), a rate-limiting enzyme of the glycolytic pathway. NIK prevents autophagic degradation of HK2 through controlling cellular reactive oxygen species levels, which in turn involves modulation of glucose-6-phosphate dehydrogenase (G6PD), an enzyme that mediates production of the antioxidant NADPH. We show that the G6PD-NADPH redox system is important for HK2 stability and metabolism in activated T cells. These findings establish NIK as a pivotal regulator of T cell metabolism and highlight a post-translational mechanism of metabolic regulation.
Assuntos
Linfócitos T CD8-Positivos/enzimologia , Neoplasias do Colo/enzimologia , Metabolismo Energético , Ativação Linfocitária , Linfócitos do Interstício Tumoral/enzimologia , Melanoma Experimental/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/transplante , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Citotoxicidade Imunológica , Estabilidade Enzimática , Feminino , Glucosefosfato Desidrogenase/metabolismo , Glicólise , Hexoquinase/genética , Hexoquinase/metabolismo , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/transplante , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADP/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Microambiente Tumoral , Quinase Induzida por NF-kappaBRESUMO
Dendritic cells (DCs) play an integral role in regulating mucosal immunity and homeostasis, but the signaling network mediating this function of DCs is poorly defined. We identified the noncanonical NF-κB-inducing kinase (NIK) as a crucial mediator of mucosal DC function. DC-specific NIK deletion impaired intestinal immunoglobulin A (IgA) secretion and microbiota homeostasis, rendering mice sensitive to an intestinal pathogen, Citrobacter rodentium. DC-specific NIK was required for expression of the IgA transporter polymeric immunoglobulin receptor (pIgR) in intestinal epithelial cells, which in turn relied on the cytokine IL-17 produced by TH17 cells and innate lymphoid cells (ILCs). NIK-activated noncanonical NF-κB induced expression of IL-23 in DCs, contributing to the maintenance of TH17 cells and type 3 ILCs. Consistent with the dual functions of IL-23 and IL-17 in mucosal immunity and inflammation, NIK deficiency also ameliorated colitis induction. Thus, our data suggest a pivotal role for the NIK signaling axis in regulating DC functions in intestinal immunity and homeostasis.
Assuntos
Células Dendríticas/imunologia , Homeostase/imunologia , Imunidade nas Mucosas/imunologia , Mucosa Intestinal/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Animais , Colite/imunologia , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/imunologia , Quinase Induzida por NF-kappaBRESUMO
Metabolic fitness of T cells is crucial for immune responses against infections and tumorigenesis. Both the T cell receptor (TCR) signal and environmental cues contribute to the induction of T cell metabolic reprogramming, but the underlying mechanism is incompletely understood. Here, we identified the E3 ubiquitin ligase Peli1 as an important regulator of T cell metabolism and antitumor immunity. Peli1 ablation profoundly promotes tumor rejection, associated with increased tumor-infiltrating CD4 and CD8 T cells. The Peli1-deficient T cells display markedly stronger metabolic activities, particularly glycolysis, than wild-type T cells. Peli1 controls the activation of a metabolic kinase, mTORC1, stimulated by both the TCR signal and growth factors, and this function of Peli1 is mediated through regulation of the mTORC1-inhibitory proteins, TSC1 and TSC2. Peli1 mediates non-degradative ubiquitination of TSC1, thereby promoting TSC1-TSC2 dimerization and TSC2 stabilization. These results establish Peli1 as a novel regulator of mTORC1 and downstream mTORC1-mediated actions on T cell metabolism and antitumor immunity.
Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Glicólise/fisiologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismoRESUMO
Proinflammatory cytokine production by innate immune cells plays a crucial role in inflammatory diseases, but the molecular mechanisms controlling the inflammatory responses are poorly understood. Here, we show that TANK-binding kinase 1 (TBK1) serves as a vital regulator of proinflammatory macrophage function and protects against tissue inflammation. Myeloid cell-conditional Tbk1 knockout (MKO) mice spontaneously developed adipose hypertrophy and metabolic disorders at old ages, associated with increased adipose tissue M1 macrophage infiltration and proinflammatory cytokine expression. When fed with a high-fat diet, the Tbk1-MKO mice also displayed exacerbated hepatic inflammation and insulin resistance, developing symptoms of nonalcoholic steatohepatitis. Furthermore, myeloid cell-specific TBK1 ablation exacerbates inflammation in experimental colitis. Mechanistically, TBK1 functions in macrophages to suppress the NF-κB and MAP kinase signaling pathways and thus attenuate induction of proinflammatory cytokines, particularly IL-1ß. Ablation of IL-1 receptor 1 (IL-1R1) eliminates the inflammatory symptoms of Tbk1-MKO mice. These results establish TBK1 as a pivotal anti-inflammatory mediator that restricts inflammation in different disease models.
Assuntos
Inflamação/etiologia , Inflamação/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Proteínas Serina-Treonina Quinases/genética , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Biomarcadores , Colite/etiologia , Colite/metabolismo , Colite/patologia , Citocinas/genética , Citocinas/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Suscetibilidade a Doenças/imunologia , Regulação da Expressão Gênica , Glucose/metabolismo , Hipertrofia , Imunomodulação/genética , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Resistência à Insulina , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Especificidade de Órgãos , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Interleucina-1/deficiência , Transdução de SinaisRESUMO
Myxobacteria are fascinating prokaryotes featuring a potent capacity for producing a wealth of bioactive molecules with intricate chemical topology as well as intriguing enzymology, and thus it is critical to developing an efficient pipeline for bioprospecting. Herein, we construct the database MyxoDB, the first public compendium solely dedicated to myxobacteria, which enabled us to provide an overview of the structural diversity and taxonomic distribution of known myxobacterial natural products. Moreover, we demonstrated that the cutting-edge NMR-based metabolomics was effective to differentiate the biosynthetic priority of myxobacteria, whereby MyxoDB could greatly streamline the dereplication of multifarious known compounds and accordingly speed up the discovery of new compounds. This led to the rapid identification of a class of linear di-lipopeptides (archangimins) and a rare rearranged sterol (corasterol) that were endowed with unique chemical architectures and/or biosynthetic enzymology. We also showcased that NMR-based metabolomics, MyxoDB, and genomics can also work concertedly to accelerate the targeted discovery of a polyketidic compound pyxipyrrolone C. All in all, this study sets the stage for the discovery of many more novel natural products from underexplored myxobacterial resources.
Assuntos
Produtos Biológicos , Myxococcales , Produtos Biológicos/química , Bioprospecção , Imageamento por Ressonância Magnética , MetabolômicaRESUMO
B-cell-activating factor (BAFF) mediates B-cell survival and, when deregulated, contributes to autoimmune diseases and B-cell malignancies. The mechanism connecting BAFF receptor (BAFFR) signal to downstream pathways and pathophysiological functions is not well understood. Here we identified DYRK1a as a kinase that responds to BAFF stimulation and mediates BAFF-induced B-cell survival. B-cell-specific DYRK1a deficiency causes peripheral B-cell reduction and ameliorates autoimmunity in a mouse model of lupus. An unbiased screen identified DYRK1a as a protein that interacts with TRAF3, a ubiquitin ligase component mediating degradation of the noncanonical nuclear factor (NF)-κB-inducing kinase (NIK). DYRK1a phosphorylates TRAF3 at serine-29 to interfere with its function in mediating NIK degradation, thereby facilitating BAFF-induced NIK accumulation and noncanonical NF-κB activation. Interestingly, B-cell acute lymphoblastic leukemia (B-ALL) cells express high levels of BAFFR and respond to BAFF for noncanonical NF-κB activation and survival in a DYRK1a-dependent manner. Furthermore, DYRK1a promotes a mouse model of B-ALL through activation of the noncanonical NF-κB pathway. These results establish DYRK1a as a critical BAFFR signaling mediator and provide novel insight into B-ALL pathogenesis.
Assuntos
Autoimunidade , Fator Ativador de Células B/imunologia , Leucemia de Células B/imunologia , NF-kappa B/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Tirosina Quinases/imunologia , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos B/imunologia , Linfócitos B/patologia , Carcinogênese/imunologia , Carcinogênese/patologia , Linhagem Celular Tumoral , Humanos , Leucemia de Células B/patologia , Camundongos , Camundongos Endogâmicos C57BL , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Quinases DyrkRESUMO
Chemical redundancy of microbial natural products (NPs) underscores the importance to exploit new resources of microorganisms. Insect-associated microbes are prolific but largely underexplored sources of diverse NPs. Herein, we discovered the new compound α-l-rhamnosyl-actiphenol (1) from a millipede-associated Streptomyces sp. ML6, which is the first glycosylated cycloheximide-class natural product. Interestingly, bioinformatics analysis of the ML6 genome revealed that the biosynthesis of 1 involves a cooperation between two gene clusters (chx and rml) located distantly on the genome of ML6. We also carried out in vitro enzymatic glycosylation of cycloheximide using an exotic promiscuous glycosyltransferase BsGT-1, which resulted in the production of an additional cycloheximide glycoside cycloheximide 7-O-ß-d-glucoside (5). Although the antifungal and cytotoxic activities of the new compounds 1 and 5 were attenuated relative to those of cycloheximide, our work not only enriches the chemical repertoire of the cycloheximide family but also provides new insights into the structure-activity relationship optimization and ecological roles of cycloheximide.
Assuntos
Actinobacteria , Glicosilação , Cicloeximida , Actinobacteria/metabolismo , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , GlicosídeosRESUMO
MAIN CONCLUSION: This study suggests that stomatal and leaf structures are highly correlated, and mesophyll cell size is an important anatomical trait determining the coordination between stomatal size and mesophyll porosity. A comprehensive study of the correlations between the structural traits and on their relationships with gas exchange parameters may provide some useful information into leaf development and improvement in efficiencies of photosynthetic CO2 fixation and transpirational water loss. In the present study, nine plant materials from eight crop species were pot grown in a growth chamber. Leaf structural traits, gas exchange, and leaf nitrogen content were measured. We found that stomatal size, mesophyll cell size (MCS), and mesophyll porosity were positively correlated and that the surface areas of mesophyll cells and chloroplasts facing intercellular air spaces were positively correlated with both stomatal density and stomatal area per leaf area (SA). These results suggested that the developments of stomata and mesophyll cells are highly correlated among different crop species. Additionally, MCS was positively correlated with leaf thickness and negatively correlated with leaf density and leaf mass per area, which indicated that MCS might play an important role in leaf structural investments and physiological functions among species. In summary, this study illustrates the correlations between stomatal and mesophyll structures, and it highlights the importance of considering the covariations among leaf traits with the intent of improving photosynthesis and iWUE.
Assuntos
Células do Mesofilo , Estômatos de Plantas , Dióxido de Carbono/metabolismo , Produtos Agrícolas/metabolismo , Células do Mesofilo/metabolismo , Nitrogênio/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Estômatos de Plantas/fisiologia , Água/metabolismoRESUMO
C-type lectin receptors (CLRs) play critical roles as pattern-recognition receptors (PRRs) for sensing Candida albicans infection, which can be life-threatening for immunocompromised individuals. Here we have shown that Dectin-3 (also called CLECSF8, MCL, or Clec4d), a previously uncharacterized CLR, recognized α-mannans on the surfaces of C. albicans hyphae and induced NF-κB activation. Mice with either blockade or genetically deleted Dectin-3 were highly susceptible to C. albicans infection. Dectin-3 constantly formed heterodimers with Dectin-2, a well-characterized CLR, for recognizing C. albicans hyphae. Compared to their respective homodimers, Dectin-3 and Dectin-2 heterodimers bound α-mannans more effectively, leading to potent inflammatory responses against fungal infections. Together, our study demonstrates that Dectin-3 forms a heterodimeric PRR with Dectin-2 for sensing fungal infection and suggests that different CLRs may form different hetero- and homodimers, which provide different sensitivity and diversity for host cells to detect various microbial infections.
Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Lectinas Tipo C/metabolismo , Proteínas de Membrana/metabolismo , Animais , Ativação Enzimática , Feminino , Humanos , Hifas/imunologia , Hifas/metabolismo , Lectinas Tipo C/deficiência , Lectinas Tipo C/genética , Mananas/metabolismo , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/metabolismo , Receptores de Reconhecimento de Padrão/imunologia , Transdução de SinaisRESUMO
This study aimed to investigate the application effect of tirofiban on percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS) and its postoperative effect on C-X-C motif chemokine ligand 16 (CXCL16) level and myocardial perfusion. A total of 50 cases of patients diagnosed with acute coronary syndrome and treated in Sunshine Union Hospital (Weifang, China) were included in group A and 30 cases of healthy subjects underwent physical examination in our hospital during the same period were enrolled in group B. Tirofiban was used in group A patients during PCI. Clinical efficacy evaluation criteria were used to evaluate the efficacy after treatment. The level of CXCL16 in serum before and after treatment was detected by qRT-PCR. Receiver operating characteristic (ROC) curve was drawn to analyze the value of C-X-C Motif Chemokine Ligand in diagnosing ACS. Before treatment, CXCL16 level in group A was significantly higher than that in group B (p<0.001). After treatment, patients in TMPG grade 3 in group A were significantly increased (p<0.001). Tirofiban could improve myocardial perfusion in patients with ACS after PCI, reduce adverse events and CXCL16 levels. Serum CXCL16 is expected to be a potential diagnostic and therapeutic predictor of ACS.
Assuntos
Síndrome Coronariana Aguda/terapia , Intervenção Coronária Percutânea/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Tirofibana/uso terapêutico , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/metabolismo , Idoso , Estudos de Casos e Controles , Quimiocina CXCL16/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
PURPOSE: In this study, we examined the effect of the manipulation of exercise self-efficacy on the enjoyment of physical activity in a sample of 44 Chinese adolescents (age = 14.27 ± .87 y), including 22 boys and 22 girls. METHODS: The participants were randomized into a low-efficacy or high-efficacy condition, and their self-efficacy beliefs for engaging in moderate-intensity physical activity were manipulated by providing false feedback after a submaximal exercise test. The participants' self-efficacy was measured and compared before and after the exercise test and the participants' enjoyment of physical activity was assessed after the exercise test. RESULTS: It was found that exercise self-efficacy was successfully manipulated in the expected direction in both conditions, which significantly influenced the participants' enjoyment of physical activity. After the exercise test, the participants in the low-efficacy condition reported lower enjoyment scores relative to the high-efficacy participants. CONCLUSIONS: These results suggest that self-efficacy may have an important influence on the enjoyment of physical activity among Chinese adolescents. We recommend that physical activity promotion programs should be tailored to enhance adolescents' self-efficacy beliefs and enjoyment of the experience of physical activity.
Assuntos
Exercício Físico/psicologia , Autoeficácia , Adolescente , China , Teste de Esforço , Feminino , Humanos , Masculino , PrazerRESUMO
Previous studies indicate that both Dectin-3 (also called MCL or Clec4d) and Mincle (also called Clec4e), two C-type lectin receptors, can recognize trehalose 6,6'-dimycolate (TDM), a cell wall component from mycobacteria, and induce potent innate immune responses. Interestingly, stimulation of Dectin-3 by TDM can also induce Mincle expression, which may enhance the host innate immune system to sense Mycobacterium infection. However, the mechanism by which Dectin-3 induces Mincle expression is not fully defined. Here, we show that TDM-induced Mincle expression is dependent on Dectin-3-mediated NF-κB, but not nuclear factor of activated T-cells (NFAT), activation, and Dectin-3 induces NF-κB activation through the CARD9-BCL10-MALT1 complex. We found that bone marrow-derived macrophages from Dectin-3-deficient mice were severely defective in the induction of Mincle expression in response to TDM stimulation. This defect is correlated with the failure of TDM-induced NF-κB activation in Dectin-3-deficient bone marrow-derived macrophages. Consistently, inhibition of NF-κB, but not NFAT, impaired TDM-induced Mincle expression, whereas NF-κB, but not NFAT, binds to the Mincle promoter. Dectin-3-mediated NF-κB activation is dependent on the CARD9-Bcl10-MALT1 complex. Finally, mice deficient for Dectin-3 or CARD9 produced much less proinflammatory cytokines and keyhole limpet hemocyanin (KLH)-specific antibodies after immunization with an adjuvant containing TDM. Overall, this study provides the mechanism by which Dectin-3 induces Mincle expression in response to Mycobacterium infection, which will have significant impact to improve adjuvant and design vaccine for antimicrobial infection.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspases/metabolismo , Fatores Corda/farmacologia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Proteínas de Membrana/genética , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores Imunológicos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Adjuvantes Imunológicos/farmacologia , Animais , Proteína 10 de Linfoma CCL de Células B , Proteínas Adaptadoras de Sinalização CARD/deficiência , Caspases/deficiência , Citocinas/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lectinas Tipo C/deficiência , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Fatores de Transcrição NFATC/metabolismo , Proteínas de Neoplasias/deficiência , Regiões Promotoras Genéticas/genética , Multimerização Proteica/efeitos dos fármacos , Subunidades Proteicas/metabolismo , Receptores Imunológicos/deficiência , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/metabolismoRESUMO
Purpose: To investigate risk factors associated with the formation of parastomal hernia after Miles operation, and to provide scientific evidence for the prevention and treatment of parastomal hernia. Methods: Clinical data from 205 patients with rectal cancer undergoing Miles operation in the Department of General Surgery, Affiliated Hospital of Xuzhou Medical University between May 2016 and May 2021 were analyzed retrospectively. Fourteen potential factors were selected and analyzed by single factor analysis and two element logistic regression analysis for their potential relationship to incidence of parastomal hernia. Results: 49 cases of parastomal hernia occurred among 194 patients during follow-up (incidence 25.26%). Univariate analysis showed that age, thickness of subcutaneous abdominal fat, BMI, and stoma pathway were related to the formation of post-surgical parastomal hernia (P < 0.05). Two element logistic regression analysis showed that advanced age, thickness of subcutaneous abdominal fat, BMI > 25 kg/m2, and transperitoneal surgical approach were independent risk factors for the formation of parastomal hernia after Miles operation (P < 0.05). Conclusion: Advanced age, thickness of subcutaneous abdominal fat, BMI > 25 kg/m2, and transperitoneal surgical approach are independent risk factors for the formation of parastomal hernia after Miles.
RESUMO
Myxobacteria are a prolific source of secondary metabolites with sheer chemical complexity, intriguing biosynthetic enzymology, and diverse biological activities. In this study, we report the discovery, biosynthesis, biomimetic total synthesis, physiological function, structure-activity relationship, and self-resistance mechanism of the 5-methylated pyrazinone coralinone from a myxobacterium Corallococcus exiguus SDU70. A single NRPS/PKS gene corA was genetically and biochemically demonstrated to orchestrate coralinone, wherein the integral PKS part is responsible for installing the 5-methyl group. Intriguingly, coralinone exacerbated cellular aggregation of myxobacteria grown in liquid cultures by enhancing the secretion of extracellular matrix, and the 5-methylation is indispensable for the alleged activity. We provided an evolutionary landscape of the corA-associated biosynthetic gene clusters (BGCs) distributed in the myxobacterial realm, revealing the divergent evolution for the diversity-oriented biosynthesis of 5-alkyated pyrazinones. This phylogenetic contextualization provoked us to identify corB located in the proximity of corA as a self-resistance gene. CorB was experimentally verified to be a protease that hydrolyzes extracellular proteins to antagonize the agglutination-inducing effect of coralinone. Overall, we anticipate these findings will provide new insights into the chemical ecology of myxobacteria and lay foundations for the maximal excavation of these largely underexplored resources.
RESUMO
Breeding new and sustainable crop cultivars of high yields and desirable traits has been a major challenge for ensuring food security for the growing global human population. For polyploid crops such as wheat, introducing genetic variation from wild relatives of its subgenomes is a key strategy to improve the quality of their breeding pools. Over the past decades, considerable progress has been made in speed breeding, genome sequencing, high-throughput phenotyping and genomics-assisted breeding, which now allows us to realize whole-genome introgression from wild relatives to modern crops. Here, we present a standardized protocol to rapidly introgress the entire genome of Aegilops tauschii, the progenitor of the D subgenome of bread wheat, into elite wheat backgrounds. This protocol integrates multiple modern high-throughput technologies and includes three major phases: development of synthetic octaploid wheat, generation of hexaploid A. tauschii-wheat introgression lines (A-WIs) and homozygosis of the generated A-WIs. Our approach readily generates stable introgression lines in 2 y, thus greatly accelerating the generation of A-WIs and the introduction of desirable genes from A. tauschii to wheat cultivars. These A-WIs are valuable for wheat-breeding programs and functional gene discovery. The current protocol can be easily modified and used for introgressing the genomes of wild relatives to other polyploid crops.
Assuntos
Aegilops , Triticum , Humanos , Triticum/genética , Aegilops/genética , Melhoramento Vegetal , Mapeamento Cromossômico , PoliploidiaRESUMO
The formation of germinal centers (GCs) is crucial for humoral immunity and vaccine efficacy. Constant stimulation through microbiota drives the formation of constitutive GCs in Peyer's patches (PPs), which generate B cells that produce antibodies against gut antigens derived from commensal bacteria and infectious pathogens. However, the molecular mechanism that regulates this persistent process is poorly understood. We report that Ewing Sarcoma Breakpoint Region 1 (EWSR1) is a brake to constitutive GC generation and immunoglobulin G (IgG) production in PPs, vaccination-induced GC formation, and IgG responses. Mechanistically, EWSR1 suppresses Bcl6 upregulation after antigen encounter, thereby negatively regulating induced GC B cell generation and IgG production. We further showed that tumor necrosis factor receptor-associated factor (TRAF) 3 serves as a negative regulator of EWSR1. These results established that the TRAF3-EWSR1 signaling axis acts as a checkpoint for Bcl6 expression and GC responses, indicating that this axis is a therapeutic target to tune GC responses and humoral immunity in infectious diseases.
Assuntos
Nódulos Linfáticos Agregados , Fator 3 Associado a Receptor de TNF , Antígenos/metabolismo , Linfócitos B , Centro Germinativo , Imunoglobulina G/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , HumanosRESUMO
BACKGROUND: Phosphorylated Smad3 isoforms are reversible and antagonistic, and the tumour-suppressive pSmad3C can shift to an oncogenic pSmad3L signal. In addition, Nrf2 has a two-way regulatory effect on tumours, protecting normal cells from carcinogens and promoting tumour cell survival in chemotherapeutics. Accordingly, we hypothesised that the transformation of pSmad3C/3L is the basis for Nrf2 to produce both pro- and/or anti-tumourigenic effects in hepatocarcinogenesis. Astragaloside IV (AS-IV), the major component of Astragalus membranaceus, exerts anti-fibrogenic and carcinogenic actions. Lately, AS-IV administration could delay the occurrence of primary liver cancer by persistently inhibiting the fibrogenesis and regulating pSmad3C/3 L and Nrf2/HO-1 pathways synchronously. However, effect of AS-IV on hepatocarcinogenesis implicated in the bidirectional cross-talking of pSmad3C/3 L and Nrf2/HO-1 signalling, especially which one contributes palpably than the other still remains unclear. PURPOSE: This study aims to settle the above questions by using in vivo (pSmad3C+/- and Nrf2-/- mice) and in vitro (plasmid- or lentivirus- transfected HepG2 cells) models of HCC. STUDY DESIGN AND METHODS: The correlation of Nrf2 to pSmad3C/pSmad3L in HepG2 cells was analysed by Co-immunoprecipitation and dual-luciferase reporter assay. Pathological changes of Nrf2, pSmad3C, and pSmad3L in human HCC patients, pSmad3C+/- mice, and Nrf2-/- mice were gauged by immunohistochemical, haematoxylin and eosin staining, Masson, and immunofluorescence assays. Finally, western blot and qPCR were used to verify the bidirectional cross-talking of pSmad3C/3L and Nrf2/HO-1 signalling protein and mRNA in vivo and in vitro models of HCC. RESULTS: Histopathological manifestations and biochemical indicators revealed that pSmad3C+/- could abate the ameliorative effects of AS-IV on fibrogenic/carcinogenic mice with Nrf2/HO-1 deactivation and pSmad3C/p21 transform to pSmad3L/PAI-1//c-Myc. As expected, cell experiments confirmed that upregulating pSmad3C boosts the inhibitory activity of AS-IV on phenotypes (cell proliferation, migration and invasion), followed by a shift of pSmad3L to pSmad3C and activation of Nrf2/HO-1. Synchronously, experiments in Nrf2-/- mice and lentivirus-carried Nrf2shRNA cell echoed the results of pSmad3C knockdown. Complementarily, Nrf2 overexpression resulted in the opposite result. Furthermore, Nrf2/HO-1 contributes to AS-IV's anti-HCC effect palpably compared with pSmad3C/3L. CONCLUSION: These studies highlight that harnessing the bidirectional crosstalk pSmad3C/3 L and Nrf2/HO-1, especially Nrf2/HO-1 signalling, acts more effectively in AS-IV's anti-hepatocarcinogenesis, which may provide an important theoretical foundation for the use of AS-IV against HCC.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Camundongos , Animais , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fator 2 Relacionado a NF-E2 , Transformação Celular NeoplásicaRESUMO
The advantage of metagenomics over the culture-based natural product (NP) discovery pipeline is the ability to access the biosynthetic potential of uncultivable microbes. Advances in DNA sequencing are revolutionizing conventional metagenomics approaches for microbial NP discovery. The genomes of (in)cultivable bugs can be resolved straightforwardly from environmental samples, enabling in situ prediction of biosynthetic gene clusters (BGCs). The predicted chemical diversities could be realized not only by heterologous expression of gene clusters originating from DNA synthesis or direct cloning, but also potentially by bioinformatic-directed organic synthesis or chemoenzymatic total synthesis. In this review, we suggest that metagenomic sequencing in tandem with multidisciplinary approaches will form a versatile platform to shed light on a plethora of microbial 'dark matter'.
Assuntos
Produtos Biológicos , Metagenômica , Produtos Biológicos/metabolismo , Metagenoma , Família Multigênica , Análise de Sequência de DNARESUMO
CD8+ T cells are central mediators of immune responses against infections and cancer. Here we identified Dapl1 as a crucial regulator of CD8+ T cell responses to cancer and infections. Dapl1 deficiency promotes the expansion of tumour-infiltrating effector memory-like CD8+ T cells and prevents their functional exhaustion, coupled with increased antitumour immunity and improved efficacy of adoptive T cell therapy. Dapl1 controls activation of NFATc2, a transcription factor required for the effector function of CD8+ T cells. Although NFATc2 mediates induction of the immune checkpoint receptor Tim3, competent NFATc2 activation prevents functional exhaustion of CD8+ T cells. Interestingly, exhausted CD8+ T cells display attenuated NFATc2 activation due to Tim3-mediated feedback inhibition; Dapl1 deletion rescues NFATc2 activation and thereby prevents dysfunction of exhausted CD8+ T cells in chronic infection and cancer. These findings establish Dapl1 as a crucial regulator of CD8+ T cell immunity and a potential target for cancer immunotherapy.