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The IκB kinase complex (IKK) is a key regulator of immune responses, inflammation, cell survival, and tumorigenesis. The prosurvival function of IKK centers on activation of the transcription factor NF-κB, whose target gene products inhibit caspases and prevent prolonged JNK activation. Here, we report that inactivation of the BH3-only protein BAD by IKK independently of NF-κB activation suppresses TNFα-induced apoptosis. TNFα-treated Ikkß(-/-) mouse embryonic fibroblasts (MEFs) undergo apoptosis significantly faster than MEFs deficient in both RelA and cRel due to lack of inhibition of BAD by IKK. IKK phosphorylates BAD at serine-26 (Ser26) and primes it for inactivation. Elimination of Ser26 phosphorylation promotes BAD proapoptotic activity, thereby accelerating TNFα-induced apoptosis in cultured cells and increasing mortality in animals. Our results reveal that IKK inhibits TNFα-induced apoptosis through two distinct but cooperative mechanisms: activation of the survival factor NF-κB and inactivation of the proapoptotic BH3-only BAD protein.
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Apoptosis , Quinasa I-kappa B/metabolismo , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Proteína Letal Asociada a bcl/metabolismo , Animales , Fibroblastos/citología , Quinasa I-kappa B/genética , Ratones , Ratones Noqueados , Fosforilación , Serina/metabolismo , Proteína Letal Asociada a bcl/química , Proteína Letal Asociada a bcl/genética , Proteína bcl-X/metabolismoRESUMEN
CD4+ T cells are central mediators of protective immunity to blood-stage malaria, particularly for their capacity in orchestrating germinal center reaction and generating parasite-specific high-affinity antibodies. T follicular helper (Tfh) cells are predominant CD4+ effector T cell subset implicated in these processes, yet the factors and detailed mechanisms that assist Tfh cell development and function during Plasmodium infection are largely undefined. Here we provide evidence that receptor for activated C kinase 1 (RACK1), an adaptor protein of various intracellular signals, is not only important for CD4+ T cell expansion as previously implied but also plays a prominent role in Tfh cell differentiation and function during blood-stage Plasmodium yoelii 17XNL infection. Consequently, RACK1 in CD4+ T cells contributes significantly to germinal center formation, parasite-specific IgG production, and host resistance to the infection. Mechanistic exploration detects specific interaction of RACK1 with STAT3 in P. yoelii 17XNL-responsive CD4+ T cells, ablation of RACK1 leads to defective STAT3 phosphorylation, accompanied by substantially lower amount of STAT3 protein in CD4+ T cells, whereas retroviral overexpression of RACK1 or STAT3 in RACK1-deficient CD4+ T cells greatly restores STAT3 activity and Bcl-6 expression under the Tfh polarization condition. Further analyses suggest RACK1 positively regulates STAT3 stability by inhibiting the ubiquitin-proteasomal degradation process, thus promoting optimal STAT3 activity and Bcl-6 induction during Tfh cell differentiation. These findings uncover a novel mechanism by which RACK1 participates in posttranslational regulation of STAT3, Tfh cell differentiation, and subsequent development of anti-Plasmodium humoral immunity.
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Diferenciación Celular , Malaria , Plasmodium yoelii , Receptores de Cinasa C Activada , Factor de Transcripción STAT3 , Células T Auxiliares Foliculares , Animales , Receptores de Cinasa C Activada/metabolismo , Factor de Transcripción STAT3/metabolismo , Malaria/inmunología , Malaria/parasitología , Ratones , Plasmodium yoelii/inmunología , Células T Auxiliares Foliculares/inmunología , Células T Auxiliares Foliculares/metabolismo , Ratones Endogámicos C57BL , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Ratones Noqueados , Centro Germinal/inmunologíaRESUMEN
Viral infection triggers the activation of transcription factor IRF3, and its activity is precisely regulated for robust antiviral immune response and effective pathogen clearance. However, how full activation of IRF3 is achieved has not been well defined. Herein, we identified BLK as a key kinase that positively modulates IRF3-dependent signaling cascades and executes a pre-eminent antiviral effect. BLK deficiency attenuates RNA or DNA virus-induced ISRE activation, interferon production and the cellular antiviral response in human and murine cells, whereas overexpression of BLK has the opposite effects. BLK-deficient mice exhibit lower serum cytokine levels and higher lethality after VSV infection. Moreover, BLK deficiency impairs the secretion of downstream antiviral cytokines and promotes Senecavirus A (SVA) proliferation, thereby supporting SVA-induced oncolysis in an in vivo xenograft tumor model. Mechanistically, viral infection triggers BLK autophosphorylation at tyrosine 309. Subsequently, activated BLK directly binds and phosphorylates IRF3 at tyrosine 107, which further promotes TBK1-induced IRF3 S386 and S396 phosphorylation, facilitating sufficient IRF3 activation and downstream antiviral response. Collectively, our findings suggest that targeting BLK enhances viral clearance via specifically regulating IRF3 phosphorylation by a previously undefined mechanism.
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Proteínas Serina-Treonina Quinasas , Virosis , Humanos , Animales , Ratones , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Factor 3 Regulador del Interferón/metabolismo , Procesamiento Proteico-Postraduccional , Citocinas/metabolismo , Inmunidad Innata , Familia-src Quinasas/metabolismoRESUMEN
OBJECTIVES: To summarize the clinical characteristics and genetic variations in children with cystic fibrosis (CF) primarily presenting with pseudo-Bartter syndrome (CF-PBS), with the aim to enhance understanding of this disorder. METHODS: A retrospective analysis was performed on the clinical data of three children who were diagnosed with CF-PBS in Hunan Children's Hospital from January 2018 to August 2023, and a literature review was performed. RESULTS: All three children had the onset of the disease in infancy. Tests after admission showed hyponatremia, hypokalemia, hypochloremia, and metabolic alkalosis, and genetic testing showed the presence of compound heterozygous mutation in the CFTR gene. All three children were diagnosed with CF. Literature review obtained 33 Chinese children with CF-PBS, with an age of onset of 1-36 months and an age of diagnosis of 3-144 months. Among these children, there were 29 children with recurrent respiratory infection or persistent pneumonia (88%), 26 with malnutrition (79%), 23 with developmental retardation (70%), and 18 with pancreatitis or extrapancreatic insufficiency (55%). Genetic testing showed that c.2909G>A was the most common mutation site of the CFTR gene, with a frequency of allelic variation of 23% (15/66). CONCLUSIONS: CF may have no typical respiratory symptoms in the early stage. The possibility of CF-PBS should be considered for infants with recurrent hyponatremia, hypokalemia, hypochloremia, and metabolic alkalosis, especially those with malnutrition and developmental retardation. CFTR genetic testing should be performed as soon as possible to help with the diagnosis of CF.
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Síndrome de Bartter , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Fibrosis Quística , Mutación , Humanos , Fibrosis Quística/genética , Fibrosis Quística/complicaciones , Masculino , Femenino , Lactante , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Síndrome de Bartter/genética , Síndrome de Bartter/diagnóstico , Síndrome de Bartter/complicaciones , Preescolar , Niño , Estudios RetrospectivosRESUMEN
As one of most common and severe mental disorders, major depressive disorder (MDD) significantly increases the risks of premature death and other medical conditions for patients. Neuroinflammation is the abnormal immune response in the brain, and its correlation with MDD is receiving increasing attention. Neuroinflammation has been reported to be involved in MDD through distinct neurobiological mechanisms, among which the dysregulation of neurogenesis in the dentate gyrus (DG) of the hippocampus (HPC) is receiving increasing attention. The DG of the hippocampus is one of two niches for neurogenesis in the adult mammalian brain, and neurotrophic factors are fundamental regulators of this neurogenesis process. The reported cell types involved in mediating neuroinflammation include microglia, astrocytes, oligodendrocytes, meningeal leukocytes, and peripheral immune cells which selectively penetrate the blood-brain barrier and infiltrate into inflammatory regions. This review summarizes the functions of the hippocampus affected by neuroinflammation during MDD progression and the corresponding influences on the memory of MDD patients and model animals.
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Trastorno Depresivo Mayor , Adulto , Animales , Humanos , Trastorno Depresivo Mayor/metabolismo , Depresión , Enfermedades Neuroinflamatorias , Hipocampo/metabolismo , Neurogénesis/fisiología , MamíferosRESUMEN
Neddylation, an important type of post-translational modification, has been implicated in innate and adapted immunity. But the role of neddylation in innate immune response against RNA viruses remains elusive. Here we report that neddylation promotes RNA virus-induced type I IFN production, especially IFN-α. More importantly, myeloid deficiency of UBA3 or NEDD8 renders mice less resistant to RNA virus infection. Neddylation is essential for RNA virus-triggered activation of Ifna gene promoters. Further exploration has revealed that mammalian IRF7undergoes neddylation, which is enhanced after RNA virus infection. Even though neddylation blockade does not hinder RNA virus-triggered IRF7 expression, IRF7 mutant defective in neddylation exhibits reduced ability to activate Ifna gene promoters. Neddylation blockade impedes RNA virus-induced IRF7 nuclear translocation without hindering its phosphorylation and dimerization with IRF3. By contrast, IRF7 mutant defective in neddylation shows enhanced dimerization with IRF5, an Ifna repressor when interacting with IRF7. In conclusion, our data demonstrate that myeloid neddylation contributes to host anti-viral innate immunity through targeting IRF7 and promoting its transcriptional activity.
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Inmunidad Innata/inmunología , Factor 7 Regulador del Interferón/inmunología , Células Mieloides/inmunología , Infecciones por Virus ARN/inmunología , Virus ARN/inmunología , Animales , Factor 7 Regulador del Interferón/biosíntesis , Ratones , Células Mieloides/metabolismo , Proteína NEDD8/deficiencia , Procesamiento Proteico-Postraduccional , Ubiquitinas/deficienciaRESUMEN
The receptor for activated C kinase 1 (RACK1) adaptor protein has been implicated in viral infection. However, whether RACK1 promotes in vivo viral infection in mammals remains unknown. Moreover, it remains elusive how RACK1 is engaged in antiviral innate immune signaling. In this study, we report that myeloid RACK1 deficiency does not affect the development and survival of myeloid cells under resting conditions but renders mice less susceptible to viral infection. RACK1-deficient macrophages produce more IFN-α and IFN-ß in response to both RNA and DNA virus infection. In line with this, RACK1 suppresses transcriptional activation of type 1 IFN gene promoters in response to virus infection. Analysis of virus-mediated signaling indicates that RACK1 inhibits the phosphorylation of IRF3/7. Indeed, RACK1 interacts with IRF3/7, which is enhanced after virus infection. Further exploration indicates that virus infection triggers AMPK activation, which in turn phosphorylates RACK1 at Thr50 RACK1 phosphorylation at Thr50 enhances its interaction with IRF3/7 and thereby limits IRF3/7 phosphorylation. Thus, our results confirm that myeloid RACK1 promotes in vivo viral infection and provide insight into the control of type 1 IFN production in response to virus infection.
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Proteínas Quinasas Activadas por AMP , Factor 3 Regulador del Interferón , Proteínas Adaptadoras Transductoras de Señales , Animales , Factor 3 Regulador del Interferón/genética , Factor 3 Regulador del Interferón/metabolismo , Interferón beta/metabolismo , Ratones , Fosforilación , Receptores de Cinasa C Activada , Transducción de SeñalRESUMEN
Neddylation is a ubiquitination-like pathway that controls cell survival and proliferation by covalently conjugating NEDD8 to lysines in specific substrate proteins. However, the physiological role of neddylation in mammalian metabolism remains elusive, and no mitochondrial targets have been identified. Here, we report that mouse models with liver-specific deficiency of NEDD8 or ubiquitin-like modifier activating enzyme 3 (UBA3), the catalytic subunit of the NEDD8-activating enzyme, exhibit neonatal death with spontaneous fatty liver as well as hepatic cellular senescence. In particular, liver-specific UBA3 deficiency leads to systemic abnormalities similar to glutaric aciduria type II (GA-II), a rare autosomal recessive inherited fatty acid oxidation disorder resulting from defects in mitochondrial electron transfer flavoproteins (ETFs: ETFA and ETFB) or the corresponding ubiquinone oxidoreductase. Neddylation inhibition by various strategies results in decreased protein levels of ETFs in neonatal livers and embryonic hepatocytes. Hepatic neddylation also enhances ETF expression in adult mice and prevents fasting-induced steatosis and mortality. Interestingly, neddylation is active in hepatic mitochondria. ETFs are neddylation substrates, and neddylation stabilizes ETFs by inhibiting their ubiquitination and degradation. Moreover, certain mutations of ETFs found in GA-II patients hinder the neddylation of these substrates. Taken together, our results reveal substrates for neddylation and add insight into GA-II.
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Flavoproteínas Transportadoras de Electrones/metabolismo , Ácidos Grasos/metabolismo , Hígado/metabolismo , Deficiencia Múltiple de Acil Coenzima A Deshidrogenasa/metabolismo , Animales , Flavoproteínas Transportadoras de Electrones/genética , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Deficiencia Múltiple de Acil Coenzima A Deshidrogenasa/genética , Proteína NEDD8/genética , Proteína NEDD8/metabolismo , Oxidación-Reducción , Ubiquitinación , Ubiquitinas/genética , Ubiquitinas/metabolismoRESUMEN
The development of the cerebellum depends on intricate processes of neurogenesis, migration, and differentiation of neural stem cells (NSCs) and progenitor cells. Defective cerebellar development often results in motor dysfunctions and psychiatric disorders. Understanding the molecular mechanisms that underlie the complex development of the cerebellum will facilitate the development of novel treatment options. Here, we report that the receptor for activated C kinase (Rack1), a multifaceted signaling adaptor protein, regulates mammalian cerebellar development in a cell type-specific manner. Selective deletion of Rack1 in mouse NSCs or granule neuron progenitors (GNPs), but not Bergmann glial cells (BGs), causes severe defects in cerebellar morphogenesis, including impaired folia and fissure formation. NSCs and GNPs lacking Rack1 exhibit enhanced Wnt/ß-catenin signaling but reduced Sonic hedgehog (Shh) signaling. Simultaneous deletion of ß-catenin in NSCs, but not GNPs, significantly rescues the Rack1 mutant phenotype. Interestingly, Rack1 controls the activation of Shh signaling by regulating the ubiquitylation and stability of histone deacetylase 1 (HDAC1)/HDAC2. Suppression of HDAC1/HDAC2 activity in the developing cerebellum phenocopies the Rack1 mutant. Together, these results reveal a previously unknown role of Rack1 in controlling mammalian cerebellar development by opposite regulation of Wnt/ß-catenin and Shh signaling pathways.
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Cerebelo/crecimiento & desarrollo , Cerebelo/metabolismo , Proteínas Hedgehog/metabolismo , Receptores de Cinasa C Activada/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animales , Regulación del Desarrollo de la Expresión Génica , Proteínas Hedgehog/genética , Histona Desacetilasa 1/genética , Histona Desacetilasa 1/metabolismo , Histona Desacetilasa 2/genética , Histona Desacetilasa 2/metabolismo , Ratones , Ratones Noqueados , Células-Madre Neurales/metabolismo , Neuronas/metabolismo , Receptores de Cinasa C Activada/genética , Transducción de Señal , Proteínas Wnt/genética , beta Catenina/genéticaRESUMEN
Conventional reconnaissance camera systems have been flown on manned aircraft, where the weight, size, and power requirements are not stringent. However, today, these parameters are important for unmanned aerial vehicles (UAVs). This article provides a solution to the design of airborne large aperture infrared optical systems, based on a monocentric lens that can meet the strict criteria of aerial reconnaissance UAVs for a wide field of view (FOV) and lightness of airborne electro-optical pod cameras. A monocentric lens has a curved image plane, consisting of an array of microsensors, which can provide an image with 368 megapixels over a 100° FOV. We obtained the initial structure of a five-glass (5GS) asymmetric monocentric lens with an air gap, using ray-tracing and global optimization algorithms. According to the design results, the ground sampling distance (GSD) of the system is 0.33 m at 3000 m altitude. The full-field modulation transfer function (MTF) value of the system is more than 0.4 at a Nyquist frequency of 70 lp/mm. We present a primary thermal control method, and the image quality was steady throughout the operating temperature range. This compactness and simple structure fulfill the needs of uncrewed airborne lenses. This work may facilitate the practical application of monocentric lens in UAVs.
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SARS-CoV-2 nucleocapsid (N) protein has been proposed as a good vaccine target. N-specific T cells were observed in SARS-CoV-2 N immunized mice and COVID-19 convalescents. It is of importance to identify the T cell responses triggered by SARS-CoV-2 N protein. Intradermal immunization with SARS-CoV N protein was demonstrated to elicit non-protective T cell responses which may be avoided by intranasal vaccination. Therefore, we conducted intranasal vaccination of BALB/c mice with recombinant adenovirus type-5 expressing SARS-CoV-2 N protein. Such procedure induced CD8 T cell responses in the lung. Meanwhile CD4 T cell responses were observed in the spleen, which was associated with robust antibody production. Our study further supports the notion that SARS-CoV-2 N protein can work as a target for vaccine development.
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Anticuerpos Antivirales/inmunología , COVID-19/prevención & control , Proteínas de la Nucleocápside de Coronavirus/inmunología , Linfocitos T/inmunología , Vacunas Virales/inmunología , Administración Intranasal , Animales , Proteínas de la Nucleocápside de Coronavirus/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Fosfoproteínas/administración & dosificación , Fosfoproteínas/inmunología , SARS-CoV-2/inmunología , VacunaciónRESUMEN
CD4+ T cells play predominant roles in protective immunity against blood-stage Plasmodium infection, both for IFN-γ-dependent effector mechanisms and providing B cell helper signals. Neddylation, an ubiquitination-like process triggered by covalent conjugation of NEDD8 to specific targets, has emerged as a potential regulator of T cell activities to TCR engagement. However, its contribution to T cell-mediated immunity to blood-stage malaria remains unclear. Here using an experimental model induced by Plasmodium yoelii 17XNL, and conditional knockout mice with T cell-specific deficiency of crucial components of neddylation pathway, we demonstrate activation of neddylation in T cells during blood-stage Plasmodium infection is essential for parasite control and host survival. Mechanistically, we show that apart from promoting CD4+ T cell activation, proliferation, and development of protective T helper 1 (Th1) cell response as suggested previously, neddylation is also required for supporting CD4+ T cell survival, mainly through B-cell lymphoma-2 (Bcl-2) mediated suppression of the mitochondria-dependent apoptosis. Furthermore, we provide evidence that neddylation contributes to follicular helper T (Tfh) cell differentiation, probably via augmenting the ubiquitin ligase Itch activity and proteasomal degradation of FoxO1, thereby facilitating germinal center (GC) formation and parasite-specific antibody production. This study identifies neddylation as a positive regulator of anti-Plasmodium immunity and provides insight into an involvement of such pathway in host resistance to infectious diseases.
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Linfocitos T CD4-Positivos/inmunología , Malaria/inmunología , Proteína NEDD8/fisiología , Inmunidad Adaptativa/inmunología , Animales , Linfocitos B/inmunología , Inmunidad Celular , Interferón gamma/metabolismo , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL/fisiología , Ratones Noqueados , Proteína NEDD8/metabolismo , Plasmodium yoelii/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Células TH1/inmunologíaRESUMEN
Despite rapid progress in elucidating the molecular mechanisms of activation of the kinase IKK, the processes that regulate IKK deactivation are still unknown. Here we demonstrate that CUE domain-containing 2 (CUEDC2) interacted with IKKalpha and IKKbeta and repressed activation of the transcription factor NF-kappaB by decreasing phosphorylation and activation of IKK. Notably, CUEDC2 also interacted with GADD34, a regulatory subunit of protein phosphatase 1 (PP1). We found that IKK, CUEDC2 and PP1 existed in a complex and that IKK was released from the complex in response to inflammatory stimuli such as tumor necrosis factor. CUEDC2 deactivated IKK by recruiting PP1 to the complex. Therefore, CUEDC2 acts as an adaptor protein to target IKK for dephosphorylation and inactivation by recruiting PP1.
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Proteínas Portadoras/metabolismo , Quinasa I-kappa B/metabolismo , Proteínas de la Membrana/metabolismo , Proteína Fosfatasa 1/metabolismo , Proteínas Represoras/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Antígenos de Diferenciación/genética , Antígenos de Diferenciación/metabolismo , Proteínas Portadoras/inmunología , Dominio Catalítico , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Femenino , Humanos , Quinasa I-kappa B/química , Inflamación/inmunología , Interleucina-6/biosíntesis , Interleucina-6/genética , Macrófagos/inmunología , Macrófagos/metabolismo , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , FN-kappa B/genética , FN-kappa B/metabolismo , Fosforilación , Unión Proteica , Proteínas Represoras/inmunología , Regulación hacia ArribaRESUMEN
Rechargeable aqueous zinc-ion batteries (ZIBs) have attracted significant attention due to the distinguishing characteristics of zinc metal, including its low price, abundance in earth, safety and high theoretical specific capacity of 820 mAh g-1. Manganese dioxide (MnO2) is a promising cathode for ZIBs due to high theoretical specific capacity, high discharge voltage plateau, cost-effectiveness and nontoxicity. However, the low electronic conductivity and volumetric changes during electrochemical cycling hinder its practical utilization. Herein, we demonstrate a polyacrylic acid (PAA)-assisted assembling strategy to fabricate freestanding and flexible MnO2/carbon nanotube/PAA (MnO2/CNT/PAA) cathodes for ZIBs. PAA plays an important role in providing excellent mechanical properties to the free-standing electrode. Moreover, the presence of CNT forms an electron conductive network, and the porous structure of MnO2/CNT/PAA electrode accommodates the volumetric variations of MnO2 during charge/discharge cycling. The as-fabricated quasi-solid-state Zn-MnO2/CNT/PAA battery delivers a high charge storage capacity of 302 mAh g-1 at 0.3 A g-1 and retains 82% of the initial capacity after 1000 charge/discharge cycles at 1.5 A g-1. The calculated volumetric energy density of Zn-MnO2/CNT/PAA battery is 8.5 mW h cm-3 (with a thickness of 0.08 cm), which is significantly higher than the reported alkali-ion batteries (1.3 mW h cm-3) and comparable to supercapacitors (6.8 mW h cm-3) and Ni-Zn batteries (7.76 mW h cm-3). The current work demonstrates that free-standing MnO2/CNT/PAA composite is a promising cathode for ZIBs.
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BACKGROUND: Asthma is one of the most frequent and serious diseases worldwide. Inflammation has been reported to correlate with airway remodeling, which is critical for the progression of asthma. Better understanding of novel molecules modulating asthma and the underlying mechanism will benefit explorations of new treatments. Method: To explore the role of miR-200a and miR-200b in asthma, miR-200a mimics/inhibitor and miR-200b mimics/inhibitor were employed in A549 cells, respectively. Expression levels of inflammatory cytokines, including TNF-α, IL-4, IL-5, IL-13 and IL-1ß, were measured by quantitative real time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). A dual luciferase reporter assay was performed to identify whether miR-200a/200b directly bound to Orosomucoid 1-like 3 (ORMDL3). ERK, p-ERK and MMP-9, involved in downstream pathways of ORMDL3, were detected using qRT-PCR and western blotting. Results: MiR-200a/200b silencing significantly increased the expression of inflammatory cytokines, including TNF-α, IL-4, IL-5, IL-13 and IL-1ß, in A549 cells. ORMDL3 was the target gene of miR-200a/200b, with high expression levels in miR-200a inhibitor and miR-200b inhibitor groups. MiR-200a and miR-200b played synergistic roles in the regulation of the inflammatory effect in A549 cells. Expression levels of p-ERK and MMP-9 were significantly increased in miR-200a inhibitor and miR-200b inhibitor groups and were rescued by ERK inhibitor and MMP-9 inhibitor, respectively. Conclusion: These findings suggest that miR-200a and miR-200b are required to regulate asthma inflammation. Reduction in miR-200a/200b promotes the development of asthma inflammation by targeting ORMDL3 to activate the ERK/MMP-9 pathway. Therefore, elevating miR-200a and miR-200b and decreasing ORMDL3 might be potential strategies for inhibition of the asthma process.
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Inflamación/genética , Sistema de Señalización de MAP Quinasas/genética , Metaloproteinasa 9 de la Matriz/genética , Proteínas de la Membrana/genética , MicroARNs/genética , Transducción de Señal/genética , Células A549 , Remodelación de las Vías Aéreas (Respiratorias)/genética , Asma/genética , Línea Celular Tumoral , Citocinas/genética , Expresión Génica/genética , HumanosRESUMEN
Humans with chronic psychological stress are prone to develop multiple disorders of body function including impairment of immune system. Chronic psychological stress has been reported to have negative effects on body immune system. However, the underlying mechanisms have not been clearly demonstrated. All immune cells are derived from hematopoietic stem cells (HSC) in the bone marrow, including myeloid cells which comprise the innate immunity as a pivotal component. In this study, to explore the effects of chronic psychological stress on HSC and myeloid cells, different repeated restraint sessions were applied, including long-term mild restraint in which mice were individually subjected to a 2 h restraint session twice daily (morning and afternoon/between 9:00 and 17:00) for 4 weeks, and short-term vigorous restraint in which mice were individually subjected to a 16 h restraint session (from 17:00 to 9:00 next day) for 5 days. At the end of restraint, mice were sacrificed and the total cell numbers in the bone marrow and peripheral blood were measured by cell counting. The proportions and absolute numbers of HSC (Lin-CD117+Sca1+CD150+CD48-) and myeloid cells (CD11b+Ly6C+) were detected by fluorescence activated cell sorting (FACS) analysis. Proliferation of HSC was measured by BrdU incorporation assay. The results indicated that the absolute number of HSC was increased upon long-term mild restraint, but was decreased upon short-term vigorous restraint with impaired proliferation. Both long-term mild restraint and short-term vigorous restraint led to the accumulation of CD11b+Ly6C+ cells in the bone marrow as well as in the peripheral blood, as indicated by the absolute cell numbers. Taken together, long-term chronic stress led to increased ratio and absolute number of HSC in mice, while short-term stress had opposite effects, which suggests that stress-induced accumulation of CD11b+Ly6C+ myeloid cells might not result from increased number of HSC.
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Proliferación Celular , Células Madre Hematopoyéticas/citología , Restricción Física , Estrés Psicológico , Animales , Antígenos Ly/metabolismo , Células de la Médula Ósea/citología , Antígeno CD11b/metabolismo , Ratones , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC), the most common primary cancer of the liver, is one of the most common malignancies and the leading cause of cancer-related death worldwide. Leucine-rich repeat and sterile alpha motif containing 1 (LRSAM1) is an E3 ubiquitin ligase involved in diverse cellular activities, including the regulation of cargo sorting, cell adhesion and antibacterial autophagy. The role of LRSAM1 in HCC remains unknown. METHODS: In this study, we reviewed the TCGA database and then performed gain-of-function and loss-of-function analyses of LRSAM1 in HCC cell lines. RESULTS: We found that the mRNA expression level of LRSAM1 was significantly increased in clinical HCC tissues in the TCGA database. Transient LRSAM1 knockdown in several human HCC cell lines led to reduced growth in conventional culture conditions. Stable LRSAM1 knockdown in HepG2 cells led to impaired anchorage-independent growth whereas its stable ectopic overexpression yielded the opposite effects. LRSAM1 overexpression in HepG2 cells enhanced in vivo tumorigenicity, whereas LRSAM1 knockdown in this cell line significantly impaired tumor growth. CONCLUSIONS: Our data suggest that LRSAM1 promotes the oncogenic growth of human HCC cells, although the underlying mechanisms remain to be explored.
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As a classic differentiation agent, all-trans retinoic acid (ATRA) has been widely used in the treatment of acute promyelocytic leukemia (APL). However, the clinical application of ATRA has strict limitations, for its severe side effects due to the accumulation of peripheral blood leukocytes. The scaffold protein RACK1 (Receptor for activated C kinase 1), which regulates multiple signaling pathways, has been proposed to contribute to the survival of leukemic progenitors. But it remains unclear whether it is also involved in the oncogenic growth of APL. In the present study, we demonstrate that silencing of endogenous RACK1 expression synergized with ATRA to promote the death of NB4 and HL-60 APL cells without effect on cell differentiation induced by ATRA. Interestingly, RACK1 knockdown combined with ATRA treatment mainly induces apoptosis. It is distinct to the necrotic cell death induced by idarubicin in combination with ATRA, a regimen extensively used in the clinic to prevent neutrophil accumulation. Further exploration revealed that the lysosome-autophagy pathway is likely to be responsible for the anti-apoptotic role of RACK1. Taken together, our findings indicate that RACK1 is essential in maintaining the malignant features of APL, and targeting RACK1 may have promising therapeutic implications in the treatment of APL.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Autofagia , Leucemia Promielocítica Aguda/patología , Proteínas de Neoplasias/deficiencia , Receptores de Cinasa C Activada/deficiencia , Tretinoina/farmacología , Diferenciación Celular , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Transducción de Señal , Células Tumorales CultivadasRESUMEN
The activation of retinoic acid-inducible gene 1 (RIG-I), a cytoplasmic innate sensor for viral RNA, is tightly regulated to maintain immune homeostasis properly and prevent excessive inflammatory reactions other than initiation of antiviral innate response to eliminate RNA virus effectively. Posttranslational modifications, particularly ubiquitination, are crucial for regulation of RIG-I activity. Increasing evidence suggests that E3 ligases play important roles in various cellular processes, including cell proliferation and antiviral innate signaling. Here we identify that E3 ubiquitin ligase RING finger protein 122 (RNF122) directly interacts with mouse RIG-I through MS screening of RIG-I-interacting proteins in RNA virus-infected cells. The transmembrane domain of RNF122 associates with the caspase activation and recruitment domains (CARDs) of RIG-I; this interaction effectively triggers RING finger domain of RNF122 to deliver the Lys-48-linked ubiquitin to the Lys115 and Lys146 residues of RIG-I CARDs and promotes RIG-I degradation, resulting in a marked inhibition of RIG-I downstream signaling. RNF122 is widely expressed in various immune cells, with preferential expression in macrophages. Deficiency of RNF122 selectively increases RIG-I-triggered production of type I IFNs and proinflammatory cytokines in macrophages. RNF122-deficient mice exhibit more resistance against lethal RNA virus infection, with increased production of type I IFNs. Thus, we demonstrate that RNF122 acts as a selective negative regulator of RIG-I-triggered antiviral innate response by targeting CARDs of RIG-I and mediating proteasomal degradation of RIG-I. Our study outlines a way for E3 ligase to regulate innate sensor RIG-I for the control of antiviral innate immunity.
Asunto(s)
Inmunidad Innata , Interferón Tipo I/inmunología , Macrófagos/inmunología , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Ubiquitina-Proteína Ligasas/genética , Animales , Regulación de la Expresión Génica , Interferón Tipo I/antagonistas & inhibidores , Interferón Tipo I/biosíntesis , Macrófagos/virología , Proteínas de la Membrana/inmunología , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/inmunología , Complejo de la Endopetidasa Proteasomal/metabolismo , Dominios y Motivos de Interacción de Proteínas , Proteolisis , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptores de Superficie Celular , Virus Sendai/crecimiento & desarrollo , Virus Sendai/inmunología , Transducción de Señal , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/deficiencia , Vesiculovirus/crecimiento & desarrollo , Vesiculovirus/inmunologíaRESUMEN
The medial prefrontal cortex is involved in the process of sensory discrimination. In this study, we examined the local field potential activity response to the different stages of pain in the prelimbic cortex (PrL) which is a sub-region of the medial prefrontal cortex. Recent studies revealed extensive information about neural oscillations, but there is limited information on the local field potential profiles for acute or chronic pain, particularly in freely moving animals. This study showed that acute mechanical pain increases alpha oscillation and decreases beta and gamma oscillations before spared nerve injury surgery. Delta oscillation was decreased by chronic pain and gamma oscillation varied with time. However, acute mechanical pain stimulus had no effects on local field potential in rats under mechanical allodynia. Together, our findings provide novel insights into the role of medial prefrontal cortex local field potential activity response to pain stimulus.