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Thioredoxin-interacting protein (TXNIP) has emerged as a key player in cancer and diabetes since it targets thioredoxin (TRX)-mediated redox regulation and glucose transporter (GLUT)-mediated metabolism. TXNIP consists of two arrestin (ARR, N-ARR and C-ARR) domains at its amino-terminus and two PPxY (PY) motifs and a di-leucine (LL) motif for endocytosis at its carboxyl-terminus. Here, we report that TXNIP shuffles between TRX and GLUTs to regulate homeostasis of intracellular oxidative stress and glucose metabolism. While TXNIP functions as a gatekeeper of TRX by default, it robustly interacted with class I GLUTs through its C-ARR domain upon increase of intracellular reactive oxygen species. This interaction prompted the surface expression downregulation and lysosomal degradation of GLUTs by its carboxyl-terminal LL endocytic signaling motif to attenuate glucose uptake. Consequently, TXNIP expression significantly limited glucose uptake, leading to the suppression of glycolysis, hexosamine biosynthesis, and the pentose phosphate pathway. Our findings establish a fundamental link between ROS and glucose metabolism through TXNIP and provide a promising target for the drug development against GLUT-related metabolic disorders.
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Proteínas de Transporte , Diabetes Mellitus , Estresse Oxidativo , Tiorredoxinas , Humanos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Glucose/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Animais , CamundongosRESUMO
Introduction: The clinicopathological features of segmental membranous glomerulopathy (SMGN) have not been well characterized. The aim of this study was to investigate the prevalence and clinicopathological features of SMGN in adults. Methods: Adult patients with biopsy-confirmed SMGN in the native kidney at our center between January 2017 to September 2020 were identified. The clinicopathological features of SMGN were collected. The glomerular deposition of IgG subclasses, M-type phospholipase A2 receptor 1 (PLA2R), thrombospondin type 1 domain-containing 7A (THSD7A), and neural epidermal growth factor-like 1 protein (NELL1) were tested. Clinical and pathologic features were comparable between NELL1-positive and NELL1-negative SMGN. Results: A total of 167 patients with biopsy-proven SMGN were enrolled. During the same period, 32,640 (33.0%) out of 98,939 renal biopsies were diagnosed with membranous nephropathy (MN) in adults. SMGN accounted for 0.17% of total kidney biopsies and 0.51% of MN in adults. One hundred and fifty (89.8%) cases were isolated SMGN, and 17 (10.2%) cases were complicated with other kidney disease. Clinically, the median age of isolated SMGN patients was 41.5 years, with female (74%) predominance, and 33.1% had full nephrotic syndrome. Pathologically, IgG1 was the dominant subclass (92.5%), followed by IgG4 (45.0%). PLA2R and THSD7A staining were done in 142 and 136 isolated SMGN cases, respectively, in which, all the cases showed negative. NELL1 staining was done in 135 isolated SMGN cases; 58 cases (43.0%) showed positive. Fifty-eight patients (41.1%) had diffuse (≥90%) foot process effacement, and 119 patients (83.8%) had either stage I (38.0%) or stage II (45.8%) membranous alterations in patients with SMGN. Most patients with NELL1-positive SMGN were female. Patients with NELL1-positive SMGN were more likely with lower prevalence of full nephrotic syndrome than NELL1-negative SMGN. Conclusions: SMGN is a relatively rare pathological type. Majority of patients with isolated SMGN were female, with a median age of 41.5 years, 33.1% had full nephrotic syndrome, absence of PLA2R and THSD7A, 43.0% with NELL1-positive, and mainly stage I or II MN (83.8%). NELL1 is the major target antigen of SMGN in adults.
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Target based molecular design via the aid of computation is one of the most efficient methods in the discovery of novel pesticides. Here, a combination of the comparative molecular field analysis (CoMFA) and molecular docking was applied for discovery of potent fungicidal [1,2,4]-triazolo-[3,4-b][1,3,4]-thiadiazoles. Bioassay results indicated that the synthesized target compounds 3a, 3b, and 3c exhibited good activity against Alternaria solani, Botrytis cinerea, Cercospora arachidicola, Fusarium graminearum, Physalospora piricola, Rhizoctonia solani, and Sclerotinia sclerotiorum with an EC50 value falling between 0.64 and 16.10 µg/mL. Specially, 3c displayed excellent fungicidal activity against C. arachidicola and R. solani, which was 5 times more potent than the lead YZK-C22. The enzymatic inhibition assay and fluorescence quenching analysis with R. solani pyruvate kinase (RsPK) showed a weaker binding affinity between RsPK and 3a, 3b, or 3c. Transcriptomic analyses showed that 3c exerted its fungicidal activity by disrupting steroid biosynthesis and ribosome biogenesis in eukaryotes. These findings support that 3c is a promising fungicide candidate, and a fine modification from a lead may lead to a totally different mode of action.
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Fungicidas Industriais , Tiadiazóis , Xylariales , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Tiadiazóis/farmacologia , Antifúngicos/farmacologiaRESUMO
Strengthened glycolysis is crucial for the macrophage pro-inflammatory response during sepsis. Activating transcription factor 4 (ATF4) plays an important role in regulating glucose and lipid metabolic homeostasis in hepatocytes and adipocytes. However, its immunometabolic role in macrophage during sepsis remains largely unknown. In the present study, we found that the expression of ATF4 in peripheral blood mononuclear cells (PBMCs) was increased and associated with glucose metabolism in septic patients. Atf4 knockdown specifically decreased LPS-induced spleen macrophages and serum pro-inflammatory cytokines levels in mice. Moreover, Atf4 knockdown partially blocked LPS-induced pro-inflammatory cytokines, lactate accumulation and glycolytic capacity in RAW264.7. Mechanically, ATF4 binds to the promoter region of hexokinase II (HK2), and interacts with hypoxia inducible factor-1α (HIF-1α) and stabilizes HIF-1α through ubiquitination modification in response to LPS. Furthermore, ATF4-HIF-1α-HK2-glycolysis axis launches pro-inflammatory response in macrophage depending on the activation of mammalian target of rapamycin (mTOR). Importantly, Atf4 overexpression improves the decreased level of pro-inflammatory cytokines and lactate secretion and HK2 expression in LPS-induced tolerant macrophages. In conclusion, we propose a novel function of ATF4 as a crucial glycolytic activator contributing to pro-inflammatory response and improving immune tolerant in macrophage involved in sepsis. So, ATF4 could be a potential new target for immunotherapy of sepsis.
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Hexoquinase , Sepse , Animais , Camundongos , Fator 4 Ativador da Transcrição/metabolismo , Citocinas/metabolismo , Glicólise , Hexoquinase/genética , Hexoquinase/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Tolerância Imunológica , Ácido Láctico , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos , Macrófagos/metabolismo , Mamíferos/metabolismo , Sepse/genética , Sepse/metabolismo , UbiquitinaçãoRESUMO
As an intracellular parasite, the virus usurps cellular machinery and modulates cellular metabolism pathways to replicate itself in cells. Lipid droplets (LDs) are universally conserved energy storage organelles that not only play vital roles in maintaining lipid homeostasis but are also involved in viral replication. Increasing evidence has demonstrated that viruses take advantage of cellular lipid metabolism by targeting the biogenesis, hydrolysis, and lipophagy of LD during viral infection. In this review, we summarize the current knowledge about the modulation of cellular LD by different viruses, with a special emphasis on the Hepatitis C virus, Dengue virus, and SARS-CoV-2.
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COVID-19 , Gotículas Lipídicas , Humanos , Gotículas Lipídicas/metabolismo , COVID-19/metabolismo , SARS-CoV-2 , Metabolismo dos Lipídeos , HepacivirusRESUMO
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is undergoing continuous evolution and convergent mutation. These new subvariants are raising concerns that they may evade neutralizing monoclonal antibodies (mAbs). We investigated the serum neutralization efficacy of Evusheld (cilgavimab and tixagevimab) against SARS-CoV-2 Omicron BA.2, BA.2.75, BA.2.76, BA.5, BF.7, BQ.1.1, and XBB.1.5. A total of 90 serum samples from healthy individuals were collected in Shanghai. Anti-RBD antibodies were measured and symptoms of infection with COVID-19 were compared among those individuals. The neutralizing activity of serum against Omicron variants was analyzed by pseudovirus neutralization assays in 22 samples. Evusheld retained neutralizing activity against BA.2, BA.2.75, and BA.5, albeit with somewhat reduced titers. However, the neutralizing activity of Evusheld against BA.2.76, BF.7, BQ.1.1, and XBB.1.5 significantly decreased, with XBB.1.5 showing the greatest escape activity among the subvariants. We also observed that Evusheld recipients displayed elevated antibody levels in their serum, which efficiently neutralized the original variant, and exhibited different characteristics of infection than those who did not receive Evusheld. The mAb has partial neutralization activity against Omicron sublineages. However, the increasing doses of mAb and a larger size of population should be further investigated.
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COVID-19 , Humanos , SARS-CoV-2/genética , China , Anticorpos Neutralizantes , Anticorpos AntiviraisRESUMO
OBJECTIVES: To investigate how BBIBP-CorV vaccination affecting antibody responses upon heterologous Omicron infection. METHODS: 440 Omicron-infected patients were recruited in this study. Antibodies targeting SARS-CoV-2 spike protein receptor binding domain (RBD) and nucleoprotein of both wild-type (WT) and Omicron were detected by ELISA. The clinical relevance was further analyzed. RESULTS: BBIBP-CorV vaccinated patients exhibited higher anti-RBD IgG levels targeting both WT and Omicron than non-vaccinated patients at different stages. By using a 3-day moving average analysis, we found that BBIBP-CorV vaccinated patients exhibited the increases in both anti-WT and Omicron RBD IgG from the onset and reached the plateau at Day 8 whereas those in non-vaccinated patients remained low during the disease. Significant increase in anti-WT RBD IgA was observed only in vaccinated patients. anti-Omicron RBD IgA levels remained low in both vaccinated and non-vaccinated patients. Clinically, severe COVID-19 only occurred in non-vaccinated group. anti-RBD IgG and IgA targeting both WT and Omicron were negatively correlated with virus load, hospitalization days and virus elimination in vaccinated patients. CONCLUSIONS: BBIBP-CorV vaccination effectively reduces the severity of Omicron infected patients. The existence of humoral memory responses established through BBIBP-CorV vaccination facilitates to induce rapid recall antibody responses when encountering SARS-CoV-2 variant infection.
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Antivirais , COVID-19 , Humanos , Anticorpos Antivirais , Formação de Anticorpos , China , COVID-19/prevenção & controle , Imunoglobulina A , Imunoglobulina G , SARS-CoV-2 , Vacinação , Estudos RetrospectivosRESUMO
Kaposi sarcoma-associated herpesvirus (KSHV) is the etiological agent of several human diseases, including Kaposi sarcoma, primary effusion lymphoma, and a subset of multicentric Castleman's disease. KSHV uses its gene products to manipulate many aspects of the host responses during its life cycles. Among KSHV-encoded proteins, ORF45 is unique in both temporal and spatial expression: it is expressed as an immediate-early gene product and is an abundant tegument protein contained in the virion. ORF45 is specific to the gammaherpesvirinae subfamily but the homologs share only very limited homology and differ dramatically in protein length. In the past two decades, we and others have shown that ORF45 plays critical roles in immune evasion, viral replication, and virion assembly by targeting various host and viral factors. Herein, we summarize our current knowledge of ORF45 throughout the KSHV life cycle. We discuss the cellular processes targeted by ORF45 with emphasis on the modulation of host innate immune responses and rewiring the host signaling through impacting three major posttranslational modifications: phosphorylation, SUMOylation, and ubiquitination.
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Herpesvirus Humano 8 , Proteínas Imediatamente Precoces , Sarcoma de Kaposi , Humanos , Linhagem Celular , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Replicação Viral/fisiologiaRESUMO
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection leads to the accumulation of lipid droplets (LD), the central hubs of the lipid metabolism, in vitro or in type II pneumocytes and monocytes from coronavirus disease 19 (COVID-19) patients and blockage of LD formation by specific inhibitors impedes SARS-CoV-2 replication. Here, we showed that ORF3a is necessary and sufficient to trigger LD accumulation during SARS-CoV-2 infection, leading to efficient virus replication. Although highly mutated during evolution, ORF3a-mediated LD modulation is conserved in most SARS-CoV-2 variants except the Beta strain and is a major difference between SARS-CoV and SARS-CoV-2 that depends on the genetic variations on the amino acid position 171, 193, and 219 of ORF3a. Importantly, T223I substitution in recent Omicron strains (BA.2-BF.8) impairs ORF3a-Vps39 association and LD accumulation, leading to less efficient replication and potentially contributing to lower pathogenesis of the Omicron strains. Our work characterized how SARS-CoV-2 modulates cellular lipid homeostasis to benefit its replication during virus evolution, making ORF3a-LD axis a promising drug target for the treatment of COVID-19.
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COVID-19 , SARS-CoV-2 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Gotículas Lipídicas , SARS-CoV-2/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genéticaRESUMO
PURPOSE: Spontaneous intracerebral haemorrhage (ICH) is the main presentation in adults with moyamoya disease (MMD), an unusual clinical entity with a poor prognosis. However, optimal management in the acute stage of ICH in patients with MMD remains a challenge. Since minimally invasive surgery (MIS) plus local thrombolysis has emerged as a promising strategy for ICH, we aimed to describe our experience of performing this procedure in this special population in the acute phase, while focusing on its efficacy and safety. MATERIALS AND METHODS: The medical data of patients with ICH treated with MIS and local thrombolysis between November 2013 and December 2017 were retrospectively reviewed at our institution. MMD was identified based on the angiographic images. The primary outcome was postoperative intracranial rebleeding. The secondary outcomes were 30-day mortality and 6-month outcome graded using the modified Rankin scale (mRS). Logistic regression was applied to explore independent risk factors for the above outcomes. RESULTS: A cohort of consecutive 337 ICH patients was analysed, of whom 14 (4.15%) were diagnosed with MMD. In total, 36 (11.46%) patients experienced postoperative intracranial rehaemorrhage, of which one patient had MMD. No significant difference was found between the patients with and without MMD regarding postoperative rebleeding (9.09% vs. 11.55%, p = 1.000). Additionally, the 30-day mortality of patients with MMD was 21.42% (3/14), which was not significantly different from that of non-MMD patients (10.83%; p = 0.201). Moreover, 53.8% of patients had poor outcomes at the 6-month follow-up among MMD patients, similar to 43.9% of patients without MMD (p = 0.573). The coexistence of MMD failed to show a significant association with postoperative intracranial rebleeding (p = 0.348), 30-day mortality (p = 0.211), or poor outcome at the 6-month follow-up (p = 0.450). CONCLUSION: Our findings suggest that coexistent MMD is not associated with an increased risk of postoperative rebleeding or poor outcome after local thrombolysis for ICH.
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Doença de Moyamoya , Adulto , Humanos , Doença de Moyamoya/complicações , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/cirurgia , Terapia Trombolítica/efeitos adversos , Hematoma/cirurgiaRESUMO
The strain of Zika virus (ZIKV) that circulated during the 2015 epidemic in Brazil has been associated with more than 2000 cases of microcephaly from September 2015 through November 2016. The viral genome determines the biology and pathogenesis of a virus and the virus employs its own gene products to evade host immune surveillance, manipulate cellular machineries, and establish efficient replication. Therefore, understanding the functions of virus-encoded protein not only aids the knowledge of ZIKV biology but also guides the development of anti-ZIKV drugs. In this review, we focus on 10 proteins encoded by ZIKV and summarize their functions in ZIKV replication and pathogenesis according to studies published in the past 6 years.
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Epidemias , Microcefalia , Infecção por Zika virus , Zika virus , Humanos , Infecção por Zika virus/epidemiologia , Replicação ViralRESUMO
Simultaneous spontaneous bilateral external capsule hemorrhage is a rare clinical entity with extremely poor outcome. However, knowledge on the effective management of this fatal disease is limited. Herein,we described a case of a 42-year-old man with acute coma and quadriplegia as well as respiratory failure related to the disease. The patient underwent minimally invasive surgery plus local thrombolysis. Consequently, he recovered with satisfactory neurological function recovery on the 180th day of follow-up.
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Hemorragia dos Gânglios da Base , Coma , Masculino , Humanos , Adulto , Coma/etiologia , Cápsula Externa , Resultado do Tratamento , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia dos Gânglios da Base/complicações , Hemorragia dos Gânglios da Base/diagnóstico por imagem , Hemorragia dos Gânglios da Base/cirurgiaRESUMO
BACKGROUND: Frail and pre-frail older people often need to take medications. However, factors related to medication adherence among this population remain unclear, warranting further research. This study aims to identify correlates of medication adherence among frail and pre-frail older adults. METHODS: From November 2020 to December 2020; a total of 4218 community-dwelling residents aged ≥ 60 years were interviewed by a cross-sectional survey in China. Data on subjects' general information; medication adherence; and frailty status was obtained via the face-to-face structured questionnaire. Logistic regression models were fitted; separately; to examine these factors linked to medication adherence. RESULTS: We found that 36.2% (n = 1527) and 18.8% (n = 792) of respondents were classified as pre-frail and frail. According to the Morisky scale scores, 66.74% (n = 2815) were found to have adequate medication adherence, and 33.26% (n = 1403) were found to have inadequate medication adherence. Among the pre-frail respondents, age (adjusted odds ratio (AOR) = 1.64; 95% confidence interval (CI): 1.18-2.29, P = 0.003), marital status (AOR = 1.52; 95% CI: 1.04-2.21, P = 0.030), smoking status (AOR = 0.61; 95% CI: 0.37-0.99, P = 0.044), and functional ability (AOR = 0.72; 95% CI: 0.58-0.91, P = 0.006) were significantly related to medication adherence. Among them, advanced age and single were risk factors, which were positively related to the medication adherence of subjects in pre-frailty, while quitting smoking and limited functional ability contributed to improving their medication adherence. In contrast, only age (AOR = 1.77; 95% CI: 1.16-2.69, P = 0.008) was significantly associated with medication adherence among frail subjects. CONCLUSION: Influencing factors to medication adherence of old people in pre-frailty and frailty have been enriched, which provides a certain reference for promoting medication adherence in this population. Future adherence intervention methods should be designed based on these factors.
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Fragilidade , Vida Independente , Idoso , Humanos , Estudos Transversais , Avaliação Geriátrica , Fragilidade/epidemiologia , Idoso Fragilizado , Adesão à MedicaçãoRESUMO
α-Glucosidase inhibitors are known to prevent the digestion of carbohydrates and reduce the impact of carbohydrates on blood glucose. To develop novel α-glucosidase inhibitors, a series of 5-fluoro-2-oxindole derivatives (3a â¼ 3v) were synthesized, and their α-glucosidase inhibitory activities were investigated. Biological assessment results showed that most synthesized compounds presented potential inhibition on α-glucosidase. Among them, compounds 3d, 3f, and 3i exhibited much better inhibitory activity with IC50 values of 49.89 ± 1.16 µM, 35.83 ± 0.98 µM, and 56.87 ± 0.42 µM, respectively, which were about 10 â¼ 15 folds higher than acarbose (IC50 = 569.43 ± 43.72 µM). A kinetic mechanism study revealed that compounds 3d, 3f, and 3i inhibited the α-glucosidase in a reversible and mixed manner. Molecular docking was carried out to simulate the affinity between the compound and α-glucosidase.
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At steady state, the NOD-like receptor (NLR)-containing pyrin domain (PYD) (NLRP)1 inflammasome is maintained in an auto-inhibitory complex by dipeptidyl peptidases 8 and 9 (DPP8 and DPP9) and is activated by pathogen-encoded proteases after infection. Here, we showed that the open reading frame (ORF)45 protein of the Kaposi's sarcoma-associated herpesvirus activated the human NLRP1 (hNLRP1) inflammasome in a non-protease-dependent manner, and we additionally showed that the Linker1 region of hNLRP1, situated between the PYD and NACHT domains, was required for the auto-inhibition and non-protease-dependent activation of hNLRP1. At steady state, the interaction between Linker1 and the UPA subdomain silenced the activation of hNLRP1 in auto-inhibitory complexes either containing DPP9 or not in a manner independent of DPP9. ORF45 binding to Linker1 displaced UPA from the Linker1-UPA complex and induced the release of the C-terminal domain of hNLRP1 for inflammasome assembly. The ORF45-dependent activation of the NLRP1 inflammasome was conserved in primates but was not observed for murine NLRP1b inflammasomes.
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Herpesvirus Humano 8 , Inflamassomos , Proteínas Virais/metabolismo , Animais , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Herpesvirus Humano 8/metabolismo , Humanos , Inflamassomos/metabolismo , Camundongos , Proteínas NLR/química , Proteínas NLR/metabolismoRESUMO
The blood-brain barrier (BBB) acts as a physical and biochemical barrier that plays a fundamental role in regulating the blood-to-brain influx of endogenous and exogenous components and maintaining the homeostatic microenvironment of the central nervous system (CNS). Acute stroke leads to BBB disruption, blood substances extravasation into the brain parenchyma, and the consequence of brain edema formation with neurological impairment afterward. Caspase-1, one of the evolutionary conserved families of cysteine proteases, which is upregulated in acute stroke, mainly mediates pyroptosis and compromises BBB integrity via lytic cellular death and inflammatory cytokines release. Nowadays, targeting caspase-1 has been proven to be effective in decreasing the occurrence of hemorrhagic transformation (HT) and in attenuating brain edema and secondary damages during acute stroke. However, the underlying interactions among caspase-1, BBB, and stroke still remain ill-defined. Hence, in this review, we are concerned about the roles of caspase-1 activation and its associated mechanisms in stroke-induced BBB damage, aiming at providing insights into the significance of caspase-1 inhibition on stroke treatment in the near future.
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RSK1, an essential cellular kinase for Kaposi's sarcoma-associated herpesvirus (KSHV) replication, is highly phosphorylated and SUMOylated during KSHV lytic cycle, which determine the substrate phosphorylation and specificity of RSK1, respectively. However, the SUMO E3 ligase responsible for attaching SUMO to RSK1 has not yet been identified. By genome-wide screening, we found that KSHV ORF45 is necessary and sufficient to enhance RSK1 SUMOylation. Mechanistically, KSHV ORF45 binds to SUMOs via two classic SUMO-interacting motifs (SIMs) and functions as a SIM-dependent SUMO E3 ligase for RSK1. Mutations on these ORF45 SIMs resulted in much lower lytic gene expressions, viral DNA replication, and mature progeny virus production. Interestingly, KSHV ORF45 controls RSK1 SUMOylation and phosphorylation via two separated functional regions: SIMs and amino acid 17-90, respectively, which do not affect each other. Similar to KSHV ORF45, ORF45 of Rhesus Macaque Rhadinovirus has only one SIM and also increases RSK1 SUMOylation in a SIM-dependent manner, while other ORF45 homologues do not have this function. Our work characterized ORF45 as a novel virus encoded SUMO E3 ligase, which is required for ORF45-RSK1 axis-mediated KSHV lytic gene expression.
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Herpesvirus Humano 8 , Proteínas Imediatamente Precoces , Animais , Linhagem Celular , Replicação do DNA , DNA Viral , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Macaca mulatta/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Replicação ViralRESUMO
Zika virus (ZIKV) is linked to congenital defects including microcephaly. An infection model that can recapitulate most microcephaly-related phenotypes is crucial for understanding ZIKV pathogenesis. Here, we present a protocol to generate ZIKV from an infectious clone through a reverse genetic system and subsequently perform embryonic brain infection with the rescued ZIKV in pregnant mice. We optimized several aspects of the procedures including virus rescue and in utero injection. This protocol facilitates reproducible investigation of virus-induced cortical development defects. For complete details on the use and execution of this protocol, please refer to Zeng et al. (2020).
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Microcefalia , Malformações do Sistema Nervoso , Infecção por Zika virus , Zika virus , Animais , Pesos e Medidas Corporais , Feminino , Camundongos , Microcefalia/etiologia , Malformações do Sistema Nervoso/complicações , Gravidez , Zika virus/genética , Infecção por Zika virus/congênitoRESUMO
RSK1, a downstream kinase of the MAPK pathway, has been shown to regulate multiple cellular processes and is essential for lytic replication of a variety of viruses, including Kaposi's sarcoma-associated herpesvirus (KSHV). Besides phosphorylation, it is not known whether other post-translational modifications play an important role in regulating RSK1 function. We demonstrate that RSK1 undergoes robust SUMOylation during KSHV lytic replication at lysine residues K110, K335, and K421. SUMO modification does not alter RSK1 activation and kinase activity upon KSHV ORF45 co-expression, but affects RSK1 downstream substrate phosphorylation. Compared to wild-type RSK1, the overall phosphorylation level of RxRxxS*/T* motif is significantly declined in RSK1K110/335/421R expressing cells. Specifically, SUMOylation deficient RSK1 cannot efficiently phosphorylate eIF4B. Sequence analysis showed that eIF4B has one SUMO-interacting motif (SIM) between the amino acid position 166 and 170 (166IRVDV170), which mediates the association between eIF4B and RSK1 through SUMO-SIM interaction. These results indicate that SUMOylation regulates the phosphorylation of RSK1 downstream substrates, which is required for efficient KSHV lytic replication.
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Herpesvirus Humano 8/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Sumoilação/fisiologia , Replicação Viral/fisiologia , Linhagem Celular , HumanosRESUMO
SARS-CoV-2 outbreak has been declared by World Health Organization as a worldwide pandemic. However, there are many unknowns about the antigen-specific T-cell-mediated immune responses to SARS-CoV-2 infection. Here, we present both single-cell TCR-seq and RNA-seq to analyze the dynamics of TCR repertoire and immune metabolic functions of blood T cells collected from recently discharged COVID-19 patients. We found that while the diversity of TCR repertoire was increased in discharged patients, it returned to basal level ~1 week after becoming virus-free. The dynamics of T cell repertoire correlated with a profound shift of gene signatures from antiviral response to metabolism adaptation. We also demonstrated that the top expanded T cell clones (~10% of total T cells) display the key anti-viral features in CD8+ T cells, confirming a critical role of antigen-specific T cells in fighting against SARS-CoV-2. Our work provides a basis for further analysis of adaptive immunity in COVID-19 patients, and also has implications in developing a T-cell-based vaccine for SARS-CoV-2.