Rotavirus activates MLKL‐mediated host cellular necroptosis concomitantly with apoptosis to facilitate dissemination of viral progeny

2021 ◽  
Author(s):  
Urbi Mukhopadhyay ◽  
Upayan Patra ◽  
Pritam Chandra ◽  
Priyanka Saha ◽  
Animesh Gope ◽  
...  
Keyword(s):  
Viral Progeny

Use of Uranium-Labeled Antibodies for Electron Microscopic Localization of Various Antigens in Mammalian Cells

1967 ◽  
Vol 25 ◽  
pp. 136-137
Author(s):  
J. P. Petrali ◽  
E. J. Donati ◽  
L. A. Sternberger
Keyword(s):  
Endoplasmic Reticulum ◽  
Hela Cells ◽  
Mammalian Cells ◽  
Specific Antiserum ◽  
Electron Microscopic ◽  
E Coli ◽  
Cytoplasmic Membranes ◽  
Viral Progeny ◽  
Ultrathin Sections ◽  
Electron Microscopic Localization

Specific contrast is conferred to subcellular antigen by applying purified antibodies, exhaustively labeled with uranium under immunospecific protection, to ultrathin sections. Use of Seligman’s principle of bridging osmium to metal via thiocarbohydrazide (TCH) intensifies specific contrast. Ultrathin sections of osmium-fixed materials were stained on the grid by application of 1) thiosemicarbazide (TSC), 2) unlabeled specific antiserum, 3) uranium-labeled anti-antibody and 4) TCH followed by reosmication. Antigens to be localized consisted of vaccinia antigen in infected HeLa cells, lysozyme in monocytes of patients with monocytic or monomyelocytic leukemia, and fibrinogen in the platelets of these leukemic patients. Control sections were stained with non-specific antiserum (E. coli).In the vaccinia-HeLa system, antigen was localized from 1 to 3 hours following infection, and was confined to degrading virus, the inner walls of numerous organelles, and other structures in cytoplasmic foci. Surrounding architecture and cellular mitochondria were unstained. 8 to 14 hours after infection, antigen was localized on the outer walls of the viral progeny, on cytoplasmic membranes, and free in the cytoplasm. Staining of endoplasmic reticulum was intense and focal early, and weak and diffuse late in infection.

scholarly journals Cellular miR-101-1 Reduces Efficiently the Replication of HSV-1 in HeLa Cells

Intervirology ◽  
2021 ◽  
Vol 64 (2) ◽  
pp. 88-95
Author(s):  
Bahar Sadegh Ehdaei ◽  
Ahmad Pirouzmand ◽  
Mehdi Shabani ◽  
Arezoo Mirzaei ◽  
Sharareh Moghim
Keyword(s):  
Hela Cells ◽  
Plaque Assay ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Herpes Simplex Viruses ◽  
Viral Progeny ◽  
Immunosuppressed Patients ◽  
Health Complications ◽  
Hsv 1

<b><i>Introduction:</i></b> Herpes simplex viruses (HSVs) are widely distributed in the human population. HSV type 1 (HSV-1) is responsible for a spectrum of diseases, ranging from gingivostomatitis to keratoconjunctivitis, and encephalitis. The HSVs establish latent infections in nerve cells, and recurrences are common. Their frequent reactivation in elderly and immunosuppressed patients causes serious health complications. <b><i>Objectives:</i></b> Due to the growing resistance to its main drug, acyclovir, alternative treatments with different mechanisms of action are required. MicroRNAs regulate host and viral gene expression posttranscriptionally. Previous studies reported that mir-101-2 expression has widely participated in the regulation of HSV-1 replication. In this study, we investigate the effect of hsa-miR-101-1 in the replication of HSV-1. <b><i>Methods:</i></b> We found that transfection of miR-101-1 into HeLa cells could reduce effectively HSV-1 replication using plaque assay and real-time PCR methods. <b><i>Results:</i></b> We showed that overexpression of miR-10-1 produced less viral progeny and manifested a weaker cytopathic effect, without affecting cell viability. <b><i>Discussion/Conclusion:</i></b> This result can give us new insights into the control of HSV-1 infections.

Are phytoplankton population density maxima predictable through analysis of host and viral genomic DNA content?

2006 ◽  
Vol 86 (3) ◽  
pp. 491-498 ◽  
Author(s):  
Chris M. Brown ◽  
Janice E. Lawrence ◽  
Douglas A. Campbell
Keyword(s):  
Population Density ◽  
Dna Content ◽  
Viral Genome ◽  
Particle Assembly ◽  
Phytoplankton Population ◽  
Strong Linear Correlation ◽  
Viral Progeny ◽  
A Cell ◽  
Viral Proliferation ◽  
Viral Particle Assembly

Phytoplankton:virus interactions are important factors in aquatic nutrient cycling and community succession. The number of viral progeny resulting from an infection of a cell critically influences the propagation of infection and concomitantly the dynamics of phytoplankton populations. Host nucleotide content may be the resource limiting viral particle assembly. We present evidence for a strong linear correlation between measured viral burst sizes and viral burst sizes predicted from the host DNA content divided by the viral genome size, across a diversity of phytoplankton:viral pairs. An analysis of genome sizes therefore supports predictions of taxon-specific phytoplankton population density thresholds beyond which viral proliferation can trim populations or terminate phytoplankton blooms. We present corollaries showing that host:virus interactions may place evolutionary pressure towards genome reduction of both phytoplankton hosts and their viruses.

scholarly journals Cooperative nature of viral replication

2020 ◽  
Vol 6 (49) ◽  
pp. eabd4942
Author(s):  
Iván Andreu-Moreno ◽  
Juan-Vicente Bou ◽  
Rafael Sanjuán
Keyword(s):  
Viral Replication ◽  
Viral Fitness ◽  
Progeny Production ◽  
Short Term ◽  
Viral Particles ◽  
Viral Progeny ◽  
Cooperative Process ◽  
Complex Models ◽  
Rapid Dissemination ◽  
Human Viruses

The ability of viruses to infect their hosts depends on rapid dissemination following transmission. The notion that viral particles function as independent propagules has been challenged by recent observations suggesting that viral aggregates show enhanced infectivity and faster spread. However, these observations remain poorly understood. Here, we show that viral replication is a cooperative process, such that entry of multiple viral genome copies into the same cell disproportionately increases short-term viral progeny production. This cooperativity arises from the positive feedback established between replication templates and virus-encoded products involved in replication and should be a general feature of viruses. We develop a simple model that captures this effect, verify that cooperativity also emerges in more complex models for specific human viruses, validate our predictions experimentally using different mammalian viruses, and discuss the implications of cooperative replication for viral fitness.

scholarly journals Sumoylation of nucleoprotein (NP) mediated by activation of NADPH oxidase complex is a consequence of oxidative cellular stress during infection by Infectious salmon anemia (ISA) virus necessary to viral progeny

Virology ◽  
2019 ◽  
Vol 531 ◽  
pp. 269-279
Author(s):  
Fernanda Fredericksen ◽  
Melina Villalba ◽  
Nicolas Maldonado ◽  
Gardenia Payne ◽  
Francisco Torres ◽  
...  
Keyword(s):  
Nadph Oxidase ◽  
Cellular Stress ◽  
Infectious Salmon Anemia ◽  
Viral Progeny ◽  
Nadph Oxidase Complex ◽  
Isa Virus

scholarly journals Antiviral Activity of a Arisaema Tortuosum Leaf Extract and Some of its Constituents against Herpes Simplex Virus Type 2

Planta Medica ◽  
2020 ◽  
Vol 86 (04) ◽  
pp. 267-275 ◽  
Author(s):  
Massimo Rittà ◽  
Arianna Marengo ◽  
Andrea Civra ◽  
David Lembo ◽  
Cecilia Cagliero ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Antiviral Agents ◽  
Chloroform Extract ◽  
Health Concern ◽  
Alternative Source ◽  
Antiviral Therapies ◽  
Viral Progeny ◽  
Simplex Virus ◽  
Replicative Cycle

AbstractInfections caused by HSV-2 are a public health concern worldwide, and there is still a great demand for the discovery of novel anti-herpes virus agents effective against strains resistant to current antiviral agents. In this context, medicinal plants represent an alternative source of active compounds for developing efficient antiviral therapies. The aim of this study was to evaluate the antiviral activity of Arisaema tortuosum, a plant used in the traditional medicine of India. A chloroform soluble fraction of the leaves exhibited anti-HSV-2 activity with a selectivity index of 758. The extract was also active against acyclovir-resistant HSV-2 and HSV-1. The mechanism of action of the extract was investigated evidencing inhibition of both early and late events of the HSV-2 replicative cycle. A HPLC-PDA-MS/MS analysis showed the presence of flavonoids including apigenin and luteolin in the chloroform extract (CE). Apigenin and luteolin showed a high inhibitory activity with EC50 values of 0.05 and 0.41 µg/mL, respectively. Both compounds exhibited antiviral activity when added up to 6 h post infection and were able to reduce the viral progeny production. In addition, apigenin interfered with cell-to-cell virus spread.

scholarly journals Survivin Overexpression Has a Negative Effect on Feline Calicivirus Infection

Viruses ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 996
Author(s):  
Oscar Salvador Barrera-Vázquez ◽  
Clotilde Cancio-Lonches ◽  
Carlos Emilio Miguel-Rodríguez ◽  
Monica Margarita Valdes Pérez ◽  
Ana Lorena Gutiérrez-Escolano
Keyword(s):  
Virus Production ◽  
Feline Calicivirus ◽  
Protective Effects ◽  
Murine Norovirus ◽  
Progeny Production ◽  
Apoptotic Protein ◽  
Viral Yield ◽  
Viral Progeny ◽  
Negative Effect ◽  
Replicative Cycle

It is known that levels of the anti-apoptotic protein survivin are reduced during Murine norovirus MNV-1 and Feline calicivirus (FCV) infection as part of the apoptosis establishment required for virus release and propagation in the host. Recently, our group has reported that overexpression of survivin causes a reduction of FCV protein synthesis and viral progeny production, suggesting that survivin may affect early steps of the replicative cycle. Using immunofluorescence assays, we observed that overexpression of survivin, resulted in the reduction of FCV infection not only in transfected but also in the neighboring nontransfected CrFK cells, thus suggesting autocrine and paracrine protective effects. Cells treated with the supernatants collected from CrFK cells overexpressing survivin showed a reduction in FCV but not MNV-1 protein production and viral yield, suggesting that FCV binding and/or entry were specifically altered. The reduced ability of FCV to bind to the surface of the cells overexpressing survivin, or treated with the supernatants collected from these cells, correlate with the reduction in the cell surface of the FCV receptor, the feline junctional adhesion molecule (fJAM) 1, while no effect was observed in the cells transfected with the pAm-Cyan vector or in cells treated with the corresponding supernatants. Moreover, the overexpression of survivin affects neither Vaccinia virus (VACV) production in CrFK cells nor MNV-1 virus production in RAW 267.4 cells, indicating that the effect is specific for FCV. All of these results taken together indicate that cells that overexpress survivin, or cell treatment with the conditioned medium from these cells, results in the reduction of the fJAM-1 molecule and, therefore, a specific reduction in FCV entry and infection.

scholarly journals Hsv-1 Endocytic Entry into a Human Oligodendrocytic Cell Line Is Mediated by Clathrin and Dynamin but Not Caveolin

Viruses ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 734
Author(s):  
Beatriz Praena ◽  
Raquel Bello-Morales ◽  
José Antonio López-Guerrero
Keyword(s):  
Cell Line ◽  
Viral Entry ◽  
Cell Types ◽  
Viral Genes ◽  
Viral Progeny ◽  
The Moment ◽  
Cell Inhibition ◽  
Different Cell Types ◽  
Hsv 1

Endocytosis is a pathway used by viruses to enter cells that can be classified based on the proteins involved, such as dynamin, clathrin or caveolin. Although the entry of herpes simplex type 1 (HSV-1) by endocytosis has been documented in different cell types, its dependence on clathrin has not been described whereas its dependence on dynamin has been shown according to the cell line used. The present work shows how clathrin-mediated endocytosis (CME) is one way that HSV-1 infects the human oligodendroglial (HOG) cell line. Partial dynamin inhibition using dynasore revealed a relationship between decrease of infection and dynamin inhibition, measured by viral titration and immunoblot. Co-localization between dynamin and HSV-1 was verified by immunofluorescence at the moment of viral entry into the cell. Inhibition by chlorpromazine revealed that viral progeny also decreased when clathrin was partially inhibited in our cell line. RT-qPCR of immediately early viral genes, specific entry assays and electron microscopy all confirmed clathrin’s participation in HSV-1 entry into HOG cells. In contrast, caveolin entry assays showed no effect on the entry of this virus. Therefore, our results suggest the participation of dynamin and clathrin during endocytosis of HSV-1 in HOG cells.

Defective HIV-1 Provirus Encoding a Multitarget-Ribozyme Inhibits Accumulation of Spliced and Unspliced HIV-1 mRNAs, Reduces Infectivity of Viral Progeny, and Protects the Cells from Pathogenesis

1997 ◽  
Vol 8 (9) ◽  
pp. 1115-1124 ◽  
Author(s):  
Soon-Young Paik ◽  
Akhil Banerjea ◽  
Chang-Jie Chen ◽  
Zhiping Ye ◽  
George G. Harmison ◽  
...  
Keyword(s):  
Viral Progeny ◽  
Hiv 1
Sign in / Sign up

Export Citation Format

Share Document