Search results for "virologia"
showing 9 items of 19 documents
Cell Susceptibility to Baculovirus Transduction and Echovirus Infection Is Modified by Protein Kinase C Phosphorylation and Vimentin Organization
2013
ABSTRACT Some cell types are more susceptible to viral gene transfer or virus infection than others, irrespective of the number of viral receptors or virus binding efficacy on their surfaces. In order to characterize the cell-line-specific features contributing to efficient virus entry, we studied two cell lines (Ea.hy926 and MG-63) that are nearly nonpermissive to insect-specific baculovirus (BV) and the human enterovirus echovirus 1 (EV1) and compared their characteristics with those of a highly permissive (HepG2) cell line. All the cell lines contained high levels of viral receptors on their surfaces, and virus binding was shown to be efficient. However, in nonpermissive cells, BV and it…
Clathrin-independent entry of baculovirus triggers uptake of E. coli in non-phagocytic human cells
2008
The prototype baculovirus, Autographa californica multiple nucleopolyhedrovirus, an insect pathogen, holds great potential as a gene therapy vector. To develop transductional targeting and gene delivery by baculovirus, we focused on characterizing the nature and regulation of its uptake in human cancer cells. Baculovirus entered the cells along fluid-phase markers from the raft areas into smooth-surfaced vesicles devoid of clathrin. Notably, regulators associated with macropinocytosis, namely EIPA, Pak1, Rab34, and Rac1, had no significant effect on viral transduction, and the virus did not induce fluid-phase uptake. The internalization and nuclear uptake was, however, affected by mutants o…
Resistance to virus infection mediated by artificial microRNAs: estimating the likelilhood of escape mutants
2013
Las plantas sufren las infecciones causadas por muchos patógenos como hongos, bacterias, virus y nematodos. Las infecciones virales son persistentes y frecuentemente no se curan por el sistema inmune como en los animales. Existe una alta gama de virus de plantas, alrededor de 450 especies bien caracterizadas, que cusan una alta gama de enfermedades en plantas. Enfrentando esta situación, las planas no son meros sujetos pasivos, sino que han desarrollado mecanismos defensivos elaborados y efectivos para prevenir, o limitar, los daños causados a las infecciones virales. Entre estos mecanismos de defensa, las plantas tienen genes que confieren resistencia a virios patógenos, incluyendo los vir…
Membrane Insertion and Biogenesis of the Turnip Crinkle Virus p9 Movement Protein
2010
ABSTRACT Plant viral infection and spread depends on the successful introduction of a virus into a cell of a compatible host, followed by replication and cell-to-cell transport. The movement proteins (MPs) p8 and p9 of Turnip crinkle virus are required for cell-to-cell movement of the virus. We have examined the membrane association of p9 and found that it is an integral membrane protein with a defined topology in the endoplasmic reticulum (ER) membrane. Furthermore, we have used a site-specific photo-cross-linking strategy to study the membrane integration of the protein at the initial stages of its biosynthetic process. This process is cotranslational and proceeds through the signal recog…
Human enterovirus group B viruses rely on vimentin dynamics for efficient processing of viral nonstructural proteins
2020
We report that several viruses from the human enterovirus group B cause massive vimentin rearrangements during lytic infection. Comprehensive studies suggested that viral protein synthesis was triggering the vimentin rearrangements. Blocking the host cell vimentin dynamics with IDPN did not significantly affect the production of progeny viruses and only moderately lowered the synthesis of structural proteins such as VP1. In contrast, the synthesis of the non-structural proteins 2A, 3C, and 3D was drastically lowered. This led to attenuation of the cleavage of the host cell substrates PABP and G3BP1 and reduced caspase activation, thus leading to prolonged cell survival. Furthermore, the loc…
La consolidación de la virología y su influencia en la lucha contra la rubeola en España (1964-1975)
2017
L'objectiu de l'estudi és analitzar el desenvolupament a Espanya de la investigació sobre el virus de la rubèola pel grup liderat per Rafael Nájera Morrondo en el Centro Nacional de Virología y Ecología Sanitaria (CNVES), dirigit per Florencio Pérez Gallardo entre 1964-1975. Per a dur a terme aquest treball, Nájera va posar en marxa un conjunt de tècniques de laboratori que van permetre el diagnòstic virològic de la malaltia, la determinació de la immunitat enfront de la mateixa i l'avaluació del greu problema de salut pública que suposaven les malformacions congènites ocasionades per la infecció, i tot això va portar al disseny de campanyes de vacunació de la població susceptible. //. El o…
El papel desempeñado por los programas país de la Organización Mundial de la Salud en el desarrollo de la virología en España, 1951-1975 = The role o…
2020
En el marc de la recent historiografia sobre el paper de l'Organització Mundial de la Salut (OMS) en la modernització de la salut pública i el concepte multifacètic de salut global, s'estudia el paper dels anomenats “programes país” de l'OMS a Espanya des de la seua admissió en 1951 fins a 1975. Adoptant perspectiva històrica transnacional i emfatitzant l'estudi de la circulació de persones, coneixements i pràctiques científic-sanitàries, la nostra anàlisi se centra en els programes Espanya-0001 i Espanya-0025, a avaluar el seu paper en el desenvolupament de la virologia a Espanya i en la transformació de la salut pública. Les nostres fonts venen d'arxius històrics (OMS, Escuela Nacional de…
6-O sulfated and N-sulfated Syndecan-1 promotes baculovirus binding and entry into mammalian cells.
2013
Baculoviruses are insect-specific viruses commonly found in nature. They are not able to replicate in mammalian cells but can transduce them when equipped with an appropriate mammalian cell active expression cassette. Although the viruses have been studied in several types of mammalian cells from different origins, the receptor that baculovirus uses to enter or interact with mammalian cells has not yet been identified. Due to the wide tropism of the virus, the receptor has been suggested to be a generally found cell surface molecule. In this article, we investigated the interaction of baculovirus and mammalian cell surface heparan sulfate proteoglycans (HSPG) in more detail. Our data show t…
Quantitative microscopy reveals stepwise alteration of chromatin structure during herpesvirus infection
2019
During lytic herpes simplex virus 1 (HSV-1) infection, the expansion of the viral replication compartments leads to an enrichment of the host chromatin in the peripheral nucleoplasm. We have shown previously that HSV-1 infection induces the formation of channels through the compacted peripheral chromatin. Here, we used three-dimensional confocal and expansion microscopy, soft X-ray tomography, electron microscopy, and random walk simulations to analyze the kinetics of host chromatin redistribution and capsid localization relative to their egress site at the nuclear envelope. Our data demonstrated a gradual increase in chromatin marginalization, and the kinetics of chromatin smoothening arou…