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1.
EMBO J ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714893

ABSTRACT

The 16-subunit Constitutive Centromere-associated Network (CCAN)-based inner kinetochore is well-known for connecting centromeric chromatin to the spindle-binding outer kinetochore. Here, we report a non-canonical role for the inner kinetochore in directly regulating sister-chromatid cohesion at centromeres. We provide biochemical, X-ray crystal structure, and intracellular ectopic localization evidence that the inner kinetochore directly binds cohesin, a ring-shaped multi-subunit complex that holds sister chromatids together from S-phase until anaphase onset. This interaction is mediated by binding of the 5-subunit CENP-OPQUR sub-complex of CCAN to the Scc1-SA2 sub-complex of cohesin. Mutation in the CENP-U subunit of the CENP-OPQUR complex that abolishes its binding to the composite interface between Scc1 and SA2 weakens centromeric cohesion, leading to premature separation of sister chromatids during delayed metaphase. We further show that CENP-U competes with the cohesin release factor Wapl for binding the interface of Scc1-SA2, and that the cohesion-protecting role for CENP-U can be bypassed by depleting Wapl. Taken together, this study reveals an inner kinetochore-bound pool of cohesin, which strengthens centromeric sister-chromatid cohesion to resist metaphase spindle pulling forces.

2.
J Biomed Res ; : 1-15, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38808551

ABSTRACT

Premature ovarian insufficiency (POI) caused by chemotherapy is a common complication in female cancer survivors of childbearing age. Traditional methods including mesenchymal stem cell (MSC) transplant and hormone replacement therapy have limited clinical application due to their drawbacks, and more methods need to be developed. In the current study, the potential effects and underlying mechanisms of human umbilical cord MSC-derived extracellular vesicles (hUCMSC-EVs) were investigated in a cisplatin (CDDP)-induced POI mouse model and a human granulosa cell (GC) line. The results showed that hUCMSC-EVs significantly attenuated body weight loss, ovarian weight loss, ovary atrophy, and follicle loss in moderate-dose (1.5 mg/kg) CDDP-induced POI mice, similar to the effects observed with hUCMSCs. We further discovered that the hUCMSC-EVs might inhibit CDDP-induced ovarian GC apoptosis by upregulating anti-apoptotic miRNA levels in GCs, thereby downregulating the mRNA levels of multiple pro-apoptotic genes. In general, our findings indicate that moderate-dose chemotherapy may be a better choice for clinical oncotherapy considering the effective rescue of oncotherapy-induced ovarian damage with hUCMSC-EVs. Additionally, multiple miRNAs in hUCMSC-EVs may potentially be used to inhibit chemotherapy-induced ovarian GC apoptosis, thereby restoring ovarian function and improving the life quality of female cancer patients.

3.
Emerg Microbes Infect ; 13(1): 2307514, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38240287

ABSTRACT

Enterovirus A71 (EV-A71) is the main pathogen causing hand, foot and mouth disease (HFMD) in children and occasionally associated with neurological diseases such as aseptic meningitis, brainstem encephalitis (BE) and acute flaccid paralysis. We report here that cellular pseudokinase tribbles 3 (TRIB3) facilitates the infection of EV-A71 via dual mechanisms. In one hand, TRIB3 maintains the metabolic stability of scavenger receptor class B member 2 (SCARB2), the bona fide receptor of EV-A71, to enhance the infectious entry and spreading of the virus. On the other hand, TRIB3 facilitates the replication of EV-A71 RNA in a SCARB2-independent manner. The critical role of TRIB3 in EV-A71 infection and pathogenesis was further demonstrated in vivo in mice. In comparison to wild-type C57BL/6 mice, EV-A71 infection in TRIB3 knockdown mice (Trib3+/-) resulted in significantly lower viral loads in muscular tissues and reduced lethality and severity of clinical scores and tissue pathology. In addition, TRIB3 also promoted the replication of coxsackievirus B3 (CVB3) and coxsackievirus A16 (CVA16) in vitro. In conclusion, our results suggest that TRIB3 is one of key host cellular proteins required for the infection and pathogenesis of EV-A71 and some other human enteroviruses and may thus be a potential therapeutic target for combating the infection of those viruses.


Subject(s)
Enterovirus A, Human , Enterovirus Infections , Enterovirus , Hand, Foot and Mouth Disease , Animals , Child , Humans , Mice , Enterovirus/genetics , Enterovirus A, Human/genetics , Enterovirus Infections/complications , Hand, Foot and Mouth Disease/complications , Mice, Inbred C57BL
4.
Sci Data ; 10(1): 662, 2023 09 28.
Article in English | MEDLINE | ID: mdl-37770487

ABSTRACT

Heating and cooling in buildings accounts for over 20% of total energy consumption in China. Therefore, it is essential to understand the thermal requirements of building occupants when establishing building energy codes that would save energy while maintaining occupants' thermal comfort. This paper introduces the Chinese thermal comfort dataset, established by seven participating institutions under the leadership of Xi'an University of Architecture and Technology. The dataset comprises 41,977 sets of data collected from 49 cities across five climate zones in China over the past two decades. The raw data underwent careful quality control procedure, including systematic organization, to ensure its reliability. Each dataset contains environmental parameters, occupants' subjective responses, building information, and personal information. The dataset has been instrumental in the development of indoor thermal environment evaluation standards and energy codes in China. It can also have broader applications, such as contributing to the international thermal comfort dataset, modeling thermal comfort and adaptive behaviors, investigating regional differences in indoor thermal conditions, and examining occupants' thermal comfort responses.

5.
Brain Inj ; 37(11): 1285-1293, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37614036

ABSTRACT

BACKGROUND: Ischemia/reperfusion (I/R) is a pathological process that causes severe damage. Propofol is known to alleviate I/R-related injury; however, the exact function and underlying mechanisms are not fully understood. METHODS: Using an oxygen glucose deprivation/re-oxygenation (OGD/R) method, an in vitro I/R injury model was induced. The cell viability and the level of Fe2+, glutathione synthetase (GSH), and malondialdehyde (MDA) were evaluated using kits. Luciferase reporter gene assay, chromatin immunoprecipitation, and RNA immunoprecipitation (RIP) were used to verify the interaction between molecules. The m6A level of BECN1 mRNA was determined through methylated RIP. RESULTS: Propofol-treated OGD/R models showed reduced levels of Fe2+ and MDA, while the cell viability and the level of GSH increased. Propofol inhibited ferroptosis by down-regulating HIF-1α in OGD/R-treated HT22 cells. HIF-1α is bound to the promoter region of YTHDF1 to promote its transcription, and YTHDF1 promoted ferroptosis by stabilizing the mRNA of BECN1. The suppressive effect of propofol on OGD/R-induced ferroptosis was reversed by the overexpression of YTHDF1. CONCLUSIONS: Our study revealed that the HIF-1α/YTHDF1/BECN1 axis in OGD/R-treated HT22 cells promotes ferroptosis, and administration of propofol can inhibit this axis to avoid cell death. This study provides a novel insight for the neuroprotective function of propofol.


Subject(s)
Ferroptosis , Propofol , Humans , Propofol/pharmacology , Propofol/therapeutic use , Neurons , Cell Death , Glucose , Beclin-1 , RNA-Binding Proteins
6.
Open Life Sci ; 18(1): 20220601, 2023.
Article in English | MEDLINE | ID: mdl-37250846

ABSTRACT

In the present study, the effect of exopolysaccharides (EPSs) extracted from Pseudomonas tolaasii on the growth of Pleurotus ostreatus mycelia was determined. P. ostreatus mycelia was cultivated with different concentrations of P. tolaasii EPSs, and their mycelial growth rate, protein content, and enzyme activity were measured and compared. The results showed that EPSs inhibited the growth of P. ostreatus. The proline and vitamin C contents of P. ostreatus increased at an EPS concentration of 40%. The cellulase, α-amylase, protein, and glucose utilisation rates of P. ostreatus gradually decreased with the increase in EPS concentration. Altogether, P. tolaasii EPSs had a significant inhibitory effect on mycelial growth. Therefore, we concluded that in addition to tolaasin, EPSs may also be the virulence factors responsible for the pathogenesis of P. tolaasii.

7.
J Obstet Gynaecol ; 43(1): 2194991, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37205766

ABSTRACT

The current systematic analysis and meta-analysis was aimed to evaluate the association between radiation-induced lymphopenia (RIL) and survival of women with cervical cancer (CC). PubMed, Embase, Web of Science, and Cochrane Library were searched for relevant cohort studies comparing survival between women with CC who developed versus not developed RIL after radiotherapy. We pooled the results using a random-effects model that incorporates heterogeneity. In the meta-analysis, 952 women with CC were included from eight cohort studies. Overall, 378 (39.7%) of them had RIL after radiotherapy. During a median follow-up duration of 41.8 months, pooled results showed that RIL was independently associated with poor overall survival (hazard ratio [HR]: 2.67, 95% confidence interval [CI]: 1.81 to 3.94, p < 0.001; I2 = 20%) and progression-free survival (HR: 2.17, 95% CI: 1.58 to 2.98, p < 0.001; I2 = 0%). Predefined subgroup analyses showed similar results in patients with grade 3-4 and grade 4 RIL, in patients with RIL diagnosed during or after the radiotherapy, and in studies with quality score of seven or eight points (p values for subgroup effect all < 0.05). In conclusion, women with RIL were associated with poor survival after radiotherapy for CC.


Subject(s)
Lymphopenia , Uterine Cervical Neoplasms , Humans , Female , Uterine Cervical Neoplasms/radiotherapy , Lymphopenia/etiology , Proportional Hazards Models , Disease-Free Survival
8.
Antiviral Res ; 214: 105606, 2023 06.
Article in English | MEDLINE | ID: mdl-37076089

ABSTRACT

The emergence of SARS-CoV-2 variants represents a major threat to public health and requires identification of novel therapeutic agents to address the unmet medical needs. Small molecules impeding viral entry through inhibition of spike protein priming proteases could have potent antiviral effects against SARS-CoV-2 infection. Omicsynin B4, a pseudo-tetrapeptides identified from Streptomyces sp. 1647, has potent antiviral activity against influenza A viruses in our previous study. Here, we found omicsynin B4 exhibited broad-spectrum anti-coronavirus activity against HCoV-229E, HCoV-OC43 and SARS-CoV-2 prototype and its variants in multiple cell lines. Further investigations revealed omicsynin B4 blocked the viral entry and might be related to the inhibition of host proteases. SARS-CoV-2 spike protein mediated pseudovirus assay supported the inhibitory activity on viral entry of omicsynin B4 with a more potent inhibition of Omicron variant, especially when overexpression of human TMPRSS2. Moreover, omicsynin B4 exhibited superior inhibitory activity in the sub-nanomolar range against CTSL, and a sub-micromolar inhibition against TMPRSS2 in biochemical assays. The molecular docking analysis confirmed that omicsynin B4 fits well in the substrate binding sites and forms a covalent bond to Cys25 and Ser441 in CTSL and TMPRSS2, respectively. In conclusion, we found that omicsynin B4 may serve as a natural protease inhibitor for CTSL and TMPRSS2, blocking various coronavirus S protein-driven entry into cells. These results further highlight the potential of omicsynin B4 as an attractive candidate for broad-spectrum antiviral therapy that could rapidly respond to emerging variants of SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/metabolism , Cathepsin L/metabolism , Peptide Hydrolases , Molecular Docking Simulation , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization , Antiviral Agents/pharmacology , Serine Endopeptidases/pharmacology
9.
Biomed Res Int ; 2023: 1816818, 2023.
Article in English | MEDLINE | ID: mdl-36845635

ABSTRACT

In order to explore the clinical efficacy of knowledge, information, and action theory combined with clinical nursing in children with asthmatic bronchitis (AB) and to analyze the influencing factors of poor prognosis, a total of 98 children with AB in our hospital from January 2021 to August 2022 are collected. The baseline data are analyzed and are randomly divided into a combination group (n = 49) and a single group (n = 49). The experimental results show that the baseline data of the research subjects are not comparable (P > 0.05), the clinical efficacy of the combined group is higher than that of the single group, and the level of pulmonary function indexes in the combined group is significantly higher than that of the single group (P < 0.05). The observation shows that family history, repeated respiratory virus infection, and allergy history are all risk factors affecting the prognosis of children with AB.


Subject(s)
Asthma , Bronchitis , Child , Humans , Asthma/therapy , Prognosis , Retrospective Studies , Risk Factors , Treatment Outcome
11.
Antiviral Res ; 209: 105497, 2023 01.
Article in English | MEDLINE | ID: mdl-36528172

ABSTRACT

Recent studies have shown a close link between viral infections and cholesterol metabolism. Here, we reported that 7-dehydrocholesterol reductase (DHCR7), a terminal enzyme for catalyzing cholesterol synthesis in the Kandutsch-Russell pathway, is harnessed by enterovirus A71 (EV-A71) benefitting for its replication. Overexpression of DHCR7 resulted in upregulating of EV-A71 replication, while the S14A mutation, which reduces DHCR7 enzyme activity, has no effect on EV-A71 replication. Knockdown of DHCR7 expression with small interfering RNA (siRNA) or enzyme activity inhibition with pharmacological inhibitor AY9944 could significantly inhibit EV-A71 replication. Adding cholesterol to DHCR7 knockdown cells or AY9944-treated cells could rescue EV-A71 replication. More importantly, prophylactic administration of AY9944 effectively protected mice from lethal EV-A71 infection. In addition, the natural cholesterol precursor 7-dehydrocholesterol (7-DHC), which is converted to cholesterol by DHCR7, has a similar effect against EV-A71 infection. Mechanistically, AY9944 or 7-DHC treatment can specifically promote IRF3 phosphorylation to activate interferon response. Moreover, AY9944 effectively cleared coxsackievirus B3 (CVB3) and coxsackievirus A16 (CVA16) infections in vitro. In conclusion, pharmacological modulation of DHCR7 might provide a chance for treatment of enterovirus infection, including EV-A71.


Subject(s)
Coxsackievirus Infections , Enterovirus A, Human , Enterovirus Infections , Enterovirus , Animals , Mice , Enterovirus/genetics , Enterovirus A, Human/genetics , Interferons , trans-1,4-Bis(2-chlorobenzaminomethyl)cyclohexane Dihydrochloride , RNA, Small Interfering , Antigens, Viral
12.
Eur J Med Chem ; 245(Pt 1): 114906, 2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36395647

ABSTRACT

We have already reported the modification on the piperazine and phenyl rings of JNJ4796, a small-molecule fuse inhibitor targeting hemagglutinin (HA). In this study, we described the structure-activity relationship of the benzoxazole and tetrazole rings of JNJ4796. Many derivatives demonstrated good in vitro activity against IAV H1N1and Oseltamivir-resistant IAV H1N1 stains. Although compounds (R)-1e and (R)-1h exhibited excellent in vitro activity, high drug exposure level and low hERG inhibition, they displayed low oral efficacy. Excitedly, (R)-1a, a representative identified in our previous study, was found to show potent in vivo anti-IAV activity with the survival rates of 100%, 100% and 70% at 15, 5 and 1.67 mg/kg, respectively, comparable to JNJ4796. Currently, we are exploring different ways to ease its gastrointestinal response.


Subject(s)
Antiviral Agents , Benzoxazoles , Influenza A Virus, H1N1 Subtype , Piperazines , Tetrazoles , Benzoxazoles/chemistry , Benzoxazoles/pharmacology , Influenza A Virus, H1N1 Subtype/drug effects , Piperazines/chemistry , Piperazines/pharmacology , Tetrazoles/chemistry , Tetrazoles/pharmacology , Structure-Activity Relationship , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Humans
13.
BMC Pediatr ; 22(1): 522, 2022 09 02.
Article in English | MEDLINE | ID: mdl-36056317

ABSTRACT

BACKGROUND: Large-scale data on esophagogastroduodenoscopy (EGD) in China are scarce. This study aimed to assess the indications and diagnostic yield of EGD in children and the relationship between factors (such as age, sex, and indications) and diagnostic yield. METHODS: We performed a prospective cross-sectional observational study involving patients aged < 18 years who underwent diagnostic EGD. The study was conducted in five children's hospitals, each in a different city. Demographic features, indications for endoscopy, and endoscopic and histopathological findings were collected. Univariable and multivariable ordinal logistic regression analyses of the relationship between the factors and diagnostic yield were performed. RESULTS: The study included 2268 patients (male/female ratio, 1.3:1) with a median age of 8.68 years. Among the 2268 children, the most frequent indications were abdominal pain in 1954 (86.2%), recurrent vomiting in 706 (31.1%), weight loss in 343 (15.1%), and others. The endoscopic yield was 62.5% and was the highest in patients with dysphagia (90.9%). The histologic yield was 30.4% and was the highest in patients with unexplained anemia (45.5%). On multivariable regression analysis, the endoscopic yield was associated with dysphagia, gastrointestinal (GI) bleeding, and recurrent vomiting, and the histologic yield was associated with age. Different groups of patients with abdominal pain had variable probabilities of abnormal endoscopic findings. CONCLUSIONS: The most frequent indication of pediatric EGD is abdominal pain, with variable probabilities of abnormal endoscopic findings in different groups. Endoscopic yield and histologic yield are associated with certain alarming features. TRIAL REGISTRATION: The trial registration number (ClinicalTrials. gov): NCT03603093 (The study was registered on 27/07/2018).


Subject(s)
Deglutition Disorders , Abdominal Pain/diagnosis , Child , China , Cross-Sectional Studies , Endoscopy, Gastrointestinal , Female , Gastrointestinal Hemorrhage/diagnosis , Humans , Male , Prospective Studies , Retrospective Studies , Vomiting
14.
Virol J ; 19(1): 151, 2022 09 20.
Article in English | MEDLINE | ID: mdl-36127711

ABSTRACT

BACKGROUND: ß-Amyloid (Aß) protein is a pivotal pathogenetic factor in Alzheimer's disease (AD). However, increasing evidence suggests that the brain has to continuously produce excessive Aß to efficaciously prevent pathogenic micro-organism infections, which induces and accelerates the disease process of AD. Meanwhile, Aß exhibits activity against herpes simplex virus type 1 (HSV-1) and influenza A virus (IAV) replication, but not against other neurotropic viruses. Enterovirus A71 (EV-A71) is the most important neurotropic enterovirus in the post-polio era. Given the limitation of existing research on the relationship between Aß and other virus infections, this study aimed to investigate the potent activity of Aß on EV-A71 infection and extended the potential function of Aß in other unenveloped viruses may be linked to Alzheimer's disease or infectious neurological diseases. METHODS: Aß peptides 1-42 are a major pathological factor of senile plaques in Alzheimer's disease (AD). Thus, we utilized Aß1-42 as a test subject to perform our study. The production of monomer Aß1-42 and their high-molecular oligomer accumulations in neural cells were detected by immunofluorescence assay, ELISA, or Western blot assay. The inhibitory activity of Aß1-42 peptides against EV-A71 in vitro was detected by Western blot analysis or qRT-PCR. The mechanism of Aß1-42 against EV-A71 replication was analyzed by time-of-addition assay, attachment inhibition assay, pre-attachment inhibition analysis, viral-penetration inhibition assay, TEM analysis of virus agglutination, and pull-down assay. RESULTS: We found that EV-A71 infection induced Aß production and accumulation in SH-SY5Y cells. We also revealed for the first time that Aß1-42 efficiently inhibited the RNA level of EV-A71 VP1, and the protein levels of VP1, VP2, and nonstructural protein 3AB in SH-SY5Y, Vero, and human rhabdomyosarcoma (RD) cells. Mechanistically, we demonstrated that Aß1-42 primarily targeted the early stage of EV-A71 entry to inhibit virus replication by binding virus capsid protein VP1 or scavenger receptor class B member 2. Moreover, Aß1-42 formed non-enveloped EV-A71 particle aggregates within a certain period and bound to the capsid protein VP1, which partially caused Aß1-42 to prevent viruses from infecting cells. CONCLUSIONS: Our findings unveiled that Aß1-42 effectively inhibited nonenveloped EV-A71 by targeting the early phase of an EV-A71 life cycle, thereby extending the potential function of Aß in other non-envelope viruses linked to infectious neurological diseases.


Subject(s)
Alzheimer Disease , Enterovirus A, Human , Enterovirus Infections , Enterovirus , Neuroblastoma , Amyloid beta-Peptides , Antigens, Viral/genetics , Capsid Proteins/genetics , Enterovirus/genetics , Enterovirus A, Human/genetics , Humans , Peptide Fragments , RNA , Receptors, Scavenger/metabolism
15.
Cell Mol Immunol ; 19(9): 971-992, 2022 09.
Article in English | MEDLINE | ID: mdl-35970871

ABSTRACT

Pyroptosis is a form of programmed cell death mediated by gasdermin and is a product of continuous cell expansion until the cytomembrane ruptures, resulting in the release of cellular contents that can activate strong inflammatory and immune responses. Pyroptosis, an innate immune response, can be triggered by the activation of inflammasomes by various influencing factors. Activation of these inflammasomes can induce the maturation of caspase-1 or caspase-4/5/11, both of which cleave gasdermin D to release its N-terminal domain, which can bind membrane lipids and perforate the cell membrane. Here, we review the latest advancements in research on the mechanisms of pyroptosis, newly discovered influencing factors, antitumoral properties, and applications in various diseases. Moreover, this review also provides updates on potential targeted therapies for inflammation and cancers, methods for clinical prevention, and finally challenges and future directions in the field.


Subject(s)
Neoplasms , Pyroptosis , Caspases/metabolism , Humans , Inflammasomes/metabolism , Inflammation
16.
Int J Mol Sci ; 23(10)2022 May 16.
Article in English | MEDLINE | ID: mdl-35628360

ABSTRACT

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide, and there is no specific drug to treat it. Recent results showed that 17-beta-hydroxysteroid dehydrogenase type 13 (HSD17B13) is associated with liver diseases, but these conclusions are controversial. Here, we showed that HSD17B13 was more highly expressed in the livers of NAFLD patients, and high expression was induced in the livers of murine NAFLD models and cultural hepatocytes treated using various etiologies. The high HSD17B13 expression in the hepatocytes facilitated the progression of NAFLD by directly stabilizing the intracellular lipid drops and by indirectly activating hepatic stellate cells. When HSD17B13 was overexpressed in the liver, it aggravated liver steatosis and fibrosis in mice fed with a high-fat diet, while down-regulated the high expression of HSD17B13 by short hairpin RNAs produced a therapeutic effect in the NAFLD mice. We concluded that high HSD17B13 expression is a good target for the development of drugs to treat NAFLD.


Subject(s)
Non-alcoholic Fatty Liver Disease , Animals , Diet, High-Fat/adverse effects , Hepatic Stellate Cells/metabolism , Hepatocytes/metabolism , Humans , Mice , Non-alcoholic Fatty Liver Disease/metabolism
17.
Molecules ; 27(10)2022 May 18.
Article in English | MEDLINE | ID: mdl-35630700

ABSTRACT

Chronic hepatitis induced by hepatitis B virus (HBV) infection is a serious public health problem, leading to hepatic cirrhosis and liver cancer. Although the currently approved medications can reliably decrease the virus load and prevent the development of hepatic diseases, they fail to induce durable off-drug control of HBV replication in the majority of patients. The roots of Isatis indigotica Fortune ex Lindl., a traditional Chinese medicine, were frequently used for the prevention of viral disease in China. In the present study, (-)-lariciresinol ((-)-LRSL), isolated from the roots of Isatis indigotica Fortune ex Lindl., was found to inhibit HBV DNA replication of both wild-type and nucleos(t)ide analogues (NUCs)-resistant strains in vitro. Mechanism studies revealed that (-)-LRSL could block RNA production after treatment, followed by viral proteins, and then viral particles and DNA. Promoter reporter assays and RNA decaying dynamic experiments indicated that (-)-LRSL mediated HBV RNA reduction was mainly due to transcriptional inhibition rather than degradation. Moreover, (-)-LRSL in a dose-dependent manner also inhibited other animal hepadnaviruses, including woodchuck hepatitis virus (WHV) and duck hepatitis B virus (DHBV). Combining the analysis of RNA-seq, we further found that the decrease in HBV transcriptional activity by (-)-LRSL may be related to hepatocyte nuclear factor 1α (HNF1α). Taken together, (-)-LRSL represents a novel chemical entity that inhibits HBV replication by regulating HNF1α mediated HBV transcription, which may provide a new perspective for HBV therapeutics.


Subject(s)
Hepatitis B virus , Isatis , Animals , Furans , Hepatitis B virus/metabolism , Humans , Isatis/genetics , Lignans , RNA/metabolism , Viral Transcription
18.
Nucleic Acids Res ; 50(10): 5672-5687, 2022 06 10.
Article in English | MEDLINE | ID: mdl-35640614

ABSTRACT

Replication fork reversal occurs via a two-step process that entails reversal initiation and reversal extension. DNA topoisomerase IIalpha (TOP2A) facilitates extensive fork reversal, on one hand through resolving the topological stress generated by the initial reversal, on the other hand via its role in recruiting the SUMO-targeted DNA translocase PICH to stalled forks in a manner that is dependent on its SUMOylation by the SUMO E3 ligase ZATT. However, how TOP2A activities at stalled forks are precisely regulated remains poorly understood. Here we show that, upon replication stress, the SUMO-targeted ubiquitin E3 ligase RNF4 accumulates at stalled forks and targets SUMOylated TOP2A for ubiquitination and degradation. Downregulation of RNF4 resulted in aberrant activation of the ZATT-TOP2A-PICH complex at stalled forks, which in turn led to excessive reversal and elevated frequencies of fork collapse. These results uncover a previously unidentified regulatory mechanism that regulates TOP2A activities at stalled forks and thus the extent of fork reversal.


Subject(s)
DNA Replication , Genomic Instability , DNA Replication/genetics , Genomic Instability/genetics , Humans , Nuclear Proteins/metabolism , Sumoylation , Transcription Factors/genetics , Transcription Factors/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination
19.
J Virol ; 96(10): e0059822, 2022 05 25.
Article in English | MEDLINE | ID: mdl-35510863

ABSTRACT

Posttranslational modifications (PTMs) of viral proteins play critical roles in virus infection. The role of neddylation in enterovirus 71 (EV71) replication remains poorly defined. Here, we showed that the structural protein VP2 of EV71 can be modified by neural precursor cell-expressed developmentally downregulated protein 8 (NEDD8) in an E3 ligase X-linked inhibitor of apoptosis protein (XIAP)-dependent manner. Mutagenesis and biochemical analyses mapped the neddylation site at lysine 69 (K69) of VP2 and demonstrated that neddylation reduced the stability of VP2. In agreement with the essential role of VP2 in viral replication, studies with EV71 reporter viruses with wild-type VP2 (enhanced green fluorescent protein [EGFP]-EV71) and a K69R mutant VP2 (EGFP-EV71-VP2 K69R) showed that abolishment of VP2 neddylation increased EV71 replication. In support of this finding, overexpression of NEDD8 significantly inhibited the replication of wild-type EV71 and EGFP-EV71, but not EGFP-EV71-VP2 K69R, whereas pharmacologic inhibition of neddylation with the NEDD8-activating enzyme inhibitor MLN4924 promoted the replication of EV71 in biologically relevant cell types. Our results thus support the notion that EV71 replication can be negatively regulated by host cellular and pathobiological cues through neddylation of VP2 protein. IMPORTANCE Neddylation is a ubiquitin-like posttranslational modification by conjugation of neural precursor cell-expressed developmentally downregulated protein 8 (NEDD8) to specific proteins for regulation of their metabolism and biological activities. In this study, we demonstrated for the first time that EV71 VP2 protein is neddylated at K69 residue to promote viral protein degradation and consequentially suppress multiplication of the virus. Our findings advance knowledge related to the roles of VP2 in EV71 virulence and the neddylation pathway in the host restriction of EV71 infection.


Subject(s)
Capsid Proteins , Enterovirus A, Human , Protein Processing, Post-Translational , Virus Replication , Animals , Capsid Proteins/chemistry , Cell Line, Tumor , Chlorocebus aethiops , Enterovirus A, Human/physiology , HEK293 Cells , Humans , NEDD8 Protein/metabolism , Vero Cells , X-Linked Inhibitor of Apoptosis Protein/metabolism
20.
Adv Sci (Weinh) ; 9(21): e2200470, 2022 07.
Article in English | MEDLINE | ID: mdl-35603968

ABSTRACT

Microbes with complex functions have been found to be a potential component in tumor microenvironments. Due to their low biomass and other obstacles, intratumor microbiota is poorly understood. Mucosal sites and normal adjacent tissues are important sources of intratumor microbiota, while hematogenous spread also leads to the invasion of microbes. Intratumor microbiota affects the progression of tumors through several mechanisms, such as DNA damage, activation of oncogenic pathways, induction of immunosuppression, and metabolization of drugs. Notably, in different types of tumors, the composition and abundance of intratumor microbiota are highly heterogeneous and may play different roles in the progression of tumors. Because of the concern in this field, several techniques such as omics and immunological methods have been used to study intratumor microbiota. Here, recent progress in this field is reviewed, including the potential sources of intratumor microbiota, their functions and related mechanisms, and their heterogeneity. Techniques that can be used to study intratumor microbiota are also discussed. Moreover, research is summarized into the development of strategies that can be used in antitumor treatment and prospects for possible future research in this field.


Subject(s)
Microbiota , Neoplasms , Humans , Neoplasms/therapy , Tumor Microenvironment
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