A5037974736- Hepatitis C virus research
- Liver Disease Diagnosis and Treatment
- Hepatitis B Virus Studies
- Barrier Structure and Function Studies
- Lipid Membrane Structure and Behavior
- Sphingolipid Metabolism and Signaling
- Viral Infections and Vectors
- Monoclonal and Polyclonal Antibodies Research
- Cellular transport and secretion
- SARS-CoV-2 and COVID-19 Research
- Endoplasmic Reticulum Stress and Disease
- Mosquito-borne diseases and control
- Viral Infections and Outbreaks Research
- Cholesterol and Lipid Metabolism
- HIV Research and Treatment
- Fire effects on ecosystems
- Systemic Lupus Erythematosus Research
- Drug Transport and Resistance Mechanisms
- Lipid metabolism and biosynthesis
- Peroxisome Proliferator-Activated Receptors
- Genomics, phytochemicals, and oxidative stress
- Diabetes and associated disorders
- Erythrocyte Function and Pathophysiology
- Phagocytosis and Immune Regulation
- HIV/AIDS drug development and treatment
National Institute of Infectious Diseases
2016-2025
Tokyo University of Science
2015-2024
Target (United States)
2024
The University of Tokyo
1992-2017
Osaka University
2014-2017
Kobe University
2017
National Institute of Health Sciences
2014-2017
National Institute of Biomedical Innovation, Health and Nutrition
2017
National Institutes of Health
2000-2015
Ehime University
2015
Hepatitis B virus (HBV) entry has been analyzed using infection-susceptible cells, including primary human hepatocytes, tupaia and HepaRG cells. Recently, the sodium taurocholate cotransporting polypeptide (NTCP) membrane transporter was reported as an HBV receptor. In this study, we established a strain of HepG2 cells engineered to overexpress NTCP gene (HepG2-hNTCP-C4 cells). HepG2-hNTCP-C4 were shown be susceptible infection by blood–borne cell culture-derived HBV. facilitated pretreating...
In this study, we establish that cholesterol and sphingolipid associated with hepatitis C virus (HCV) particles are important for virion maturation infectivity. a recently developed culture system enabling study of the complete life cycle HCV, mature virions were enriched as assessed by molar ratio to phospholipid in cell membranes. Depletion from or hydrolysis virion-associated sphingomyelin almost completely abolished HCV Supplementation cholesterol-depleted exogenous enhanced infectivity...
Hepatitis C virus (HCV) is a positive-strand RNA virus, and classified within the Flaviridae family. Atg7-knockdown decreases amount of HCV replicon RNA, when JFH1 subgenomic are transfected into Huh7.5 cells. However, infectious naive particles directly infected Huh7.5.1 cells, it still unclear whether production intracellular HCV-related proteins, mRNA particles. When Atg7 protein in HCV-infected cells was knocked down by RNA-interference, levels core, NS3, NS5A secreted albumin remained...
LY-A strain is a Chinese hamster ovary cell mutant resistant to sphingomyelin (SM)-directed cytolysin and has defect in de novo SM synthesis. Metabolic labeling experiments with radioactive serine, sphingosine, choline showed that cells were defective synthesis of from these precursors, but not syntheses ceramide (Cer), glycosphingolipids, or phosphatidylcholine, indicating specific the conversion Cer cells. In vitro formation was due alterations enzymatic activities responsible for...
Journal Article Proteomic Profiling of Lipid Droplet Proteins in Hepatoma Cell Lines Expressing Hepatitis C Virus Core Protein Get access Shigeko Sato, Sato *To whom correspondence should be addressed. Tel: +81-3-5285-1111, Fax: +81-3-5285-1157, E-mail: fuka@nih.go.jp Search for other works by this author on: Oxford Academic PubMed Google Scholar Masayoshi Fukasawa, Fukasawa Yoshio Yamakawa, Yamakawa Tohru Natsume, Natsume Tetsuro Suzuki, Suzuki Ikuo Shoji, Shoji Hideki Aizaki, Aizaki Tatsuo...
Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) catalyze compartment-specific membrane fusion. Whereas most SNAREs are bona fide type II proteins, Ykt6 lacks a proteinaceous anchor but contains prenylation consensus motif (CAAX box) and exists in an inactive cytosolic active membrane-bound form. We demonstrate that both forms farnesylated at the carboxyl-terminal cysteine of CCAIM sequence. Farnesylation is prerequisite for subsequent palmitoylation upstream...
Ceramide produced at the endoplasmic reticulum (ER) is transported to lumen of Golgi apparatus for conversion sphingomyelin (SM).N-(3-Hydroxy-1-hydroxymethyl-3-phenylpropyl)dodecanamide (HPA-12) a novel analog ceramide. Metabolic labeling experiments showed that HPA-12 inhibits ceramide SM, but not glucosylceramide, in Chinese hamster ovary cells. Cultivation cells with significantly reduced content SM. did inhibit activity SM synthase. The inhibition formation by was abrogated when made...
Hepatitis C virus (HCV) core protein is a major component of viral nucleocapsid and multifunctional involved in pathogenesis hepatocarcinogenesis. We previously showed that the HCV degraded through ubiquitin-proteasome pathway. However, molecular machinery for ubiquitylation unknown. Using tandem affinity purification, we identified ubiquitin ligase E6AP as an core-binding protein. was found to bind vitro vivo promote its degradation hepatic nonhepatic cells. Knockdown endogenous by RNA...
Recognition of viral RNA structures by the intracytosolic helicase RIG-I triggers induction innate immunity. Efficient requires ubiquitination E3 ligase TRIM25, its interaction with mitochondria-bound MAVS protein, recruitment TRAF3, IRF3- and NF-κB-kinases transcription Interferon (IFN). In addition, IRF3 alone induces some Interferon-Stimulated Genes (ISGs), referred to as early ISGs. Infection hepatocytes Hepatitis C virus (HCV) results in poor production IFN despite recognition but can...
Genetic and biochemical evidence has established that a SNARE complex consisting of syntaxin 5 (Sed5)-mYkt6 (Ykt6)-GOS28 (Gos1)-GS15 (Sft1) is required for transport proteins across the Golgi stack in animals (yeast). We have utilized quantitative immunogold labeling to establish cis-trans distribution v-SNARE GS15 t-SNARE subunits GOS28 5. Whereas nearly even from cis trans side, present gradient increasing concentration toward face stack. This contrasts with second distinct complex, also...
Viruses hijack and modify host cell functions to maximize viral proliferation. Hepatitis C virus (HCV) reorganizes metabolism produce specialized membrane structures organelles such as double-membrane vesicles enlarged lipid droplets (LDs), thereby enabling replication assembly. However, the molecular bases of these host–HCV interactions are largely unknown. Here, using a chemical screen, we demonstrate that benzamide derivative flutamide reduces capacity infectious HCV. Flutamide disrupted...
Hepatitis C virus (HCV) entry into host cells is a complex process requiring multiple factors, including claudin-1 (CLDN1). Safe and effective therapeutic inhibitors need to be developed. We isolated human hepatic Huh7.5.1-derived cell mutant that nonpermissive HCV, comparative microarray analysis showed the was CLDN1 defective. Four hybridomas were obtained, which produced monoclonal antibodies (MAbs) interacted with parental Huh7.5.1 but not CLDN1-defective mutant. All MAbs by these...
We examined the effects of reduction sphingomyelin level on cholesterol behavior in cells using 2 types Chinese hamster ovary cell mutants deficient synthesis: LY-A strain defective intracellular trafficking ceramide for synthesis, and LY-B enzyme catalyzing initial step sphingolipid biosynthesis. Although content was approximately 40 15%, respectively, wild-type without accumulation ceramide, these mutant were almost identical also plasma membrane to cells. However, density gradient...
Multipurpose cohort studies have demonstrated that coffee consumption reduces the risk of hepatocellular carcinoma (HCC). Given one main causes HCC is hepatitis C virus (HCV) infection, we examined effect caffeic acid, a major organic acid derived from coffee, on propagation HCV using an in vitro naïve particle-infection and production system within human hepatoma-derived Huh-7.5.1-8 cells. When cells were treated with 1% extract or 0.1% for 1-h post amount particles released into medium at...
The human hepatoma-derived HuH-7 cell line and its derivatives (Huh7.5 Huh7.5.1) have been widely used as a convenient experimental substitute for primary hepatocytes. In particular, these lines represent host cells suitable propagating the hepatitis C virus (HCV) in vitro. Huh7.5.1-8 line, subline of Huh7.5.1, can propagate HCV more efficiently than parental cells. To provide genomic information cells' quality control, we performed whole-genome sequencing identified their characteristic...
Previous reports assumed that sphingomyelin (SM) is essential for HCV replication, but the mechanism was unclear. In this study, we showed first time SM and ceramide transfer protein (CERT), which in biosynthesis pathway, are of double-membrane vesicles (DMVs), sites viral replication. Low numbers DMVs were observed CERT-KO cells transfected with replicon RNA or constructs drive production a replication-independent system. replication rescued by ectopic expression CERT protein, not mutants,...
Highlights•Anti-SARS-CoV-2 bispecific Abs can be generated by combining non-neutralizing Abs•Anti-S2 antibody CvMab-62 recognizes a novel epitope upstream of S2 stem helix•Bispecific antibodies inhibit spike-mediated membrane fusogenic mechanism•Bispecific restore antiviral activity against bebtelovimab-resistant BQ.1.1SummaryA current challenge is the emergence SARS-CoV-2 variants, such as BQ.1.1 and XBB.1.5, that evade immune defenses, thereby limiting drug effectiveness. Emergency-use...
Most of experiments for HCV infection have been done using lytic systems, in which HCV-infected cells inevitably die. Here, to elucidate metabolic alteration a more stable condition, we established an HCV-persistently-infected cell line, designated as HPI cells. This line has displayed prominent steatosis and supported than 2 years, is the longest ever reported. It enabled us analyze metabolism integrally combining metabolomics expression arrays. revealed that rate-limiting enzymes...
We have purified dipeptidyl peptidase III (EC 3.4.14.4) from human placenta. It had a pH optimum of 8.8 and readily hydrolysed Arg-Arg-beta-naphthylamide. Monoamino acid-, Gly-Phe-, Gly-Pro- Bz-Arg-beta-naphthylamides were not at all. The enzyme was inhibited by p-chloromercuriphenylsulphonic acid, metal chelators 3,4-dichloroisocoumarin contained 1 mol zinc per enzyme. dissociation constant 250 fM 7. 4 as determined the binding study. isolated, immunological screening Uni-ZAP XR cDNA...