Search results for "isäntäsolut"

G2/M checkpoint regulation and apoptosis facilitate the nuclear egress of parvoviral capsids

2022

The nuclear export factor CRM1-mediated pathway is known to be important for the nuclear egress of progeny parvovirus capsids in the host cells with virus-mediated cell cycle arrest at G2/M. However, it is still unclear whether this is the only pathway by which capsids exit the nucleus. Our studies show that the nuclear egress of DNA-containing full canine parvovirus. capsids was reduced but not fully inhibited when CRM1-mediated nuclear export was prevented by leptomycin B. This suggests that canine parvovirus capsids might use additional routes for nuclear escape. This hypothesis was further supported by our findings that nuclear envelope (NE) permeability was increased at the late stages…

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…

Interactions of virus proteins within the host cell

2014

Nuclear entry and egress of parvoviruses.

2022

Parvoviruses are small non-enveloped single-stranded DNA viruses, which depend on host cell nuclear transcriptional and replication machinery. After endosomal exposure of nuclear localization sequence and a phospholipase A2 domain on the capsid surface, and escape into the cytosol, parvovirus capsids enter the nucleus. Due to the small capsid diameter of 18–26 nm, intact capsids can potentially pass into the nucleus through nuclear pore complexes (NPCs). This might be facilitated by active nuclear import, but capsids may also follow an alternative entry pathway that includes activation of mitotic factors and local transient disruption of the nuclear envelope. The nuclear entry is followed b…

Distinctive Evasion Mechanisms to Allow Persistence of Borrelia burgdorferi in Different Human Cell Lines

2021

Lyme borreliosis is a multisystemic disease caused by the pleomorphic bacteria of the Borrelia burgdorferi sensu lato complex. The exact mechanisms for the infection to progress into a prolonged sequelae of the disease are currently unknown, although immune evasion and persistence of the bacteria in the host are thought to be major contributors. The current study investigated B. burgdorferi infection processes in two human cell lines, both non-immune and non-phagocytic, to further understand the mechanisms of infection of this bacterium. By utilizing light, confocal, helium ion, and transmission electron microscopy, borrelial infection of chondrosarcoma (SW1353) and dermal fibroblast (BJ) c…

Exploring phage-bacterium interactions : new ways to combat a fish pathogen

2014

Virus-cell interactions as a pathological mechanism of parvovirus infection

2014

The activation of aggresomal pathway in Coxsackievirus B3 infection

2016

Aggresomin muodostuminen on yksi solun puolustusmekanismeista, joka pyrkii estämään proteiinien haitallisen aggregoitumisen solulimassa. Aikaisemmat kokeet ovat näyttäneet, että ihmisen enterovirus-infektio aiheuttaa muutoksia vimentiinissä, tyypin III välikokoisessa filamentissa (Turkki et al., julkaisematon data). Nämä muutokset ovat hyvin samankaltaisia aggresomin muodostumisen aikana tapahtuvien muutoksien kanssa. Tämän tutkimuksen tarkoituksena oli selvittää mahdollisen aggresomin muodostumisreitin aktivoituminen Coxsackievirus B3 (CVB3) -infektiossa, ja hypoteesimme oli, että häkkimäisten vimentiinirakenteiden muodostumisen lisäksi myös muita aggresomin muodostumisreitin aktivoitumise…

Soft X-ray Tomography Reveals HSV-1-Induced Remodeling of Human B Cells.

2022

Upon infection, viruses hijack the cell machinery and remodel host cell structures to utilize them for viral proliferation. Since viruses are about a thousand times smaller than their host cells, imaging virus-host interactions at high spatial resolution is like looking for a needle in a haystack. Scouting gross cellular changes with fluorescent microscopy is only possible for well-established viruses, where fluorescent tagging is developed. Soft X-ray tomography (SXT) offers 3D imaging of entire cells without the need for chemical fixation or labeling. Here, we use full-rotation SXT to visualize entire human B cells infected by the herpes simplex virus 1 (HSV-1). We have mapped the temporo…