Polydnavirus replication and tissue organization of infected cells in the parasitic wasp Diadegma terebrans

1987 ◽  
Vol 33 (2) ◽  
pp. 176-183 ◽  
Author(s):  
Peter J. Krell
Keyword(s):  
Nuclear Envelope ◽  
Size Range ◽  
Parasitic Wasp ◽  
Parasitic Wasps ◽  
Tissue Organization ◽  
Large Sector ◽  
Infected Cells ◽  
Diadegma Terebrans ◽  
Virus Morphology ◽  
Lateral Oviduct

Female parasitic wasps of the species Diadegma terebrans produce a polydnavirus, DtPV, in cells of the calyx. The virus morphology is similar to that of other polydnaviruses. It has a segmented superhelical DNA genome with an estimated size range of 2.3 to 5.5 kilobases. DtPV replication starts within large nuclei where nucleocapsids assemble and become enveloped. They bud through the nuclear envelope and are then "secreted" through the apical microvilli into either the calyx lumen directly or into a channel which is continuous with the lumen. DtPV-producing cells are distributed throughout the length of the calyx and form a discrete, one cell thick "tissue" within it. The large, sector-shaped, DtPV-producing cells form a semicircle around the calyx lumen near the ovariole end of the calyx. This semicircle of DtPV-infected cells increases in circumference towards the lateral oviduct end of the calyx until they completely encircle the lumen and form the major component of the calyx wall.

scholarly journals Virus-Mediated Cell-Cell Fusion

2020 ◽  
Vol 21 (24) ◽  
pp. 9644
Author(s):  
Héloïse Leroy ◽  
Mingyu Han ◽  
Marie Woottum ◽  
Lucie Bracq ◽  
Jérôme Bouchet ◽  
...  
Keyword(s):  
Cell Fusion ◽  
Fusion Proteins ◽  
Target Cells ◽  
Special Focus ◽  
Human Pathogens ◽  
General Process ◽  
Tissue Organization ◽  
Donor Cells ◽  
Infected Cells ◽  
Cell Cell

Cell-cell fusion between eukaryotic cells is a general process involved in many physiological and pathological conditions, including infections by bacteria, parasites, and viruses. As obligate intracellular pathogens, viruses use intracellular machineries and pathways for efficient replication in their host target cells. Interestingly, certain viruses, and, more especially, enveloped viruses belonging to different viral families and including human pathogens, can mediate cell-cell fusion between infected cells and neighboring non-infected cells. Depending of the cellular environment and tissue organization, this virus-mediated cell-cell fusion leads to the merge of membrane and cytoplasm contents and formation of multinucleated cells, also called syncytia, that can express high amount of viral antigens in tissues and organs of infected hosts. This ability of some viruses to trigger cell-cell fusion between infected cells as virus-donor cells and surrounding non-infected target cells is mainly related to virus-encoded fusion proteins, known as viral fusogens displaying high fusogenic properties, and expressed at the cell surface of the virus-donor cells. Virus-induced cell-cell fusion is then mediated by interactions of these viral fusion proteins with surface molecules or receptors involved in virus entry and expressed on neighboring non-infected cells. Thus, the goal of this review is to give an overview of the different animal virus families, with a more special focus on human pathogens, that can trigger cell-cell fusion.

scholarly journals SINC, a type III secreted protein of Chlamydia psittaci, targets the inner nuclear membrane of infected cells and uninfected neighbors

2015 ◽  
Vol 26 (10) ◽  
pp. 1918-1934 ◽  
Author(s):  
Sergio A. Mojica ◽  
Kelley M. Hovis ◽  
Matthew B. Frieman ◽  
Bao Tran ◽  
Ru-ching Hsia ◽  
...  
Keyword(s):  
Nuclear Envelope ◽  
Nuclear Membrane ◽  
Nuclear Lamina ◽  
Chlamydia Psittaci ◽  
Hek293 Cells ◽  
Secreted Protein ◽  
Inner Nuclear Membrane ◽  
Type Iii ◽  
Infected Cells ◽  
Digitonin Permeabilization

SINC, a new type III secreted protein of the avian and human pathogen Chlamydia psittaci, uniquely targets the nuclear envelope of C. psittaci–infected cells and uninfected neighboring cells. Digitonin-permeabilization studies of SINC-GFP–transfected HeLa cells indicate that SINC targets the inner nuclear membrane. SINC localization at the nuclear envelope was blocked by importazole, confirming SINC import into the nucleus. Candidate partners were identified by proximity to biotin ligase-fused SINC in HEK293 cells and mass spectrometry (BioID). This strategy identified 22 candidates with high confidence, including the nucleoporin ELYS, lamin B1, and four proteins (emerin, MAN1, LAP1, and LBR) of the inner nuclear membrane, suggesting that SINC interacts with host proteins that control nuclear structure, signaling, chromatin organization, and gene silencing. GFP-SINC association with the native LEM-domain protein emerin, a conserved component of nuclear “lamina” structure, or with a complex containing emerin was confirmed by GFP pull down. Our findings identify SINC as a novel bacterial protein that targets the nuclear envelope with the capability of globally altering nuclear envelope functions in the infected host cell and neighboring uninfected cells. These properties may contribute to the aggressive virulence of C. psittaci.

scholarly journals pUL21 regulation of pUs3 Kinase Activity Influences the Nature of Nuclear Envelope Deformation by the HSV-2 Nuclear Egress Complex

2021 ◽  
Author(s):  
Jamil H Muradov ◽  
Renee L Finnen ◽  
Michael A Gulak ◽  
Thomas J. M. Hay ◽  
Bruce W Banfield
Keyword(s):  
Nuclear Envelope ◽  
Serine Threonine Kinase ◽  
Uniform Size ◽  
Threonine Kinase ◽  
Nuclear Egress ◽  
Sds Page ◽  
Infected Cells ◽  
Simplex Virus ◽  
In Cells

It is well established that the herpesvirus nuclear egress complex (NEC) has an intrinsic ability to deform membranes. During viral infection, the membrane-deformation activity of the NEC must be precisely regulated to ensure efficient nuclear egress of capsids. One viral protein known to regulate herpes simplex virus type 2 (HSV-2) NEC activity is the tegument protein pUL21. Cells infected with an HSV-2 mutant lacking pUL21 (ΔUL21) produced a slower migrating species of the viral serine/threonine kinase pUs3 that was shown to be a hyperphosphorylated form of the enzyme. Investigation of the pUs3 substrate profile in ΔUL21-infected cells revealed a prominent band with a molecular weight consistent with that of the NEC components pUL31 and pUL34. Phosphatase sensitivity and retarded mobility in phos-tag SDS-PAGE confirmed that both pUL31 and pUL34 were hyperphosphorylated by pUs3 in the absence of pUL21. To gain insight into the consequences of increased phosphorylation of NEC components, the architecture of the nuclear envelope in cells producing the HSV-2 NEC in the presence or absence of pUs3 was examined. In cells with robust NEC production, invaginations of the inner nuclear membrane were observed that contained budded vesicles of uniform size. By contrast, nuclear envelope deformations protruding outwards from the nucleus, were observed when pUs3 was included in transfections with the HSV-2 NEC. Finally, when pUL21 was included in transfections with the HSV-2 NEC and pUs3, decreased phosphorylation of NEC components was observed in comparison to transfections lacking pUL21. These results demonstrate that pUL21 influences the phosphorylation status of pUs3 and the HSV-2 NEC and that this has consequences for the architecture of the nuclear envelope.

scholarly journals Human Adenovirus Type 5 Infection Leads to Nuclear Envelope Destabilization and Membrane Permeability Independently of Adenovirus Death Protein

2021 ◽  
Vol 22 (23) ◽  
pp. 13034
Author(s):  
Søren Pfitzner ◽  
Jens B. Bosse ◽  
Helga Hofmann-Sieber ◽  
Felix Flomm ◽  
Rudolph Reimer ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Nuclear Envelope ◽  
Membrane Permeability ◽  
Nuclear Membrane ◽  
Membrane Damage ◽  
Human Adenovirus ◽  
Adenovirus Type ◽  
Lamin A ◽  
Infected Cells ◽  
Adenovirus Type 5

The human adenovirus type 5 (HAdV5) infects epithelial cells of the upper and lower respiratory tract. The virus causes lysis of infected cells and thus enables spread of progeny virions to neighboring cells for the next round of infection. The mechanism of adenovirus virion egress across the nuclear barrier is not known. The human adenovirus death protein (ADP) facilitates the release of virions from infected cells and has been hypothesized to cause membrane damage. Here, we set out to answer whether ADP does indeed increase nuclear membrane damage. We analyzed the nuclear envelope morphology using a combination of fluorescence and state-of-the-art electron microscopy techniques, including serial block-face scanning electron microscopy and electron cryo-tomography of focused ion beam-milled cells. We report multiple destabilization phenotypes of the nuclear envelope in HAdV5 infection. These include reduction of lamin A/C at the nuclear envelope, large-scale membrane invaginations, alterations in double membrane separation distance and small-scale membrane protrusions. Additionally, we measured increased nuclear membrane permeability and detected nuclear envelope lesions under cryoconditions. Unexpectedly, and in contrast to previous hypotheses, ADP did not have an effect on lamin A/C reduction or nuclear permeability.

scholarly journals Exploring the Nuclear Envelope of Herpes Simplex Virus 1-Infected Cells by High-Resolution Microscopy

2008 ◽  
Vol 83 (1) ◽  
pp. 408-419 ◽  
Author(s):  
Peter Wild ◽  
Claudia Senn ◽  
Céline L. Manera ◽  
Esther Sutter ◽  
Elisabeth M. Schraner ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Herpes Simplex ◽  
Nuclear Envelope ◽  
Nuclear Pore ◽  
Nuclear Pores ◽  
Herpes Simplex Virus 1 ◽  
Infected Cells ◽  
The Mean ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT Herpesviruses are composed of capsid, tegument, and envelope. Capsids assemble in the nucleus and exit the nucleus by budding at the inner nuclear membrane, acquiring tegument and the envelope. This study focuses on the changes of the nuclear envelope during herpes simplex virus 1 (HSV-1) infection in HeLa and Vero cells by employing preparation techniques at ambient and low temperatures for high-resolution scanning and transmission electron microscopy and confocal laser scanning microscopy. Cryo-field emission scanning electron microscopy of freeze-fractured cells showed for the first time budding of capsids at the nuclear envelope at the third dimension with high activity at 10 h and low activity at 15 h of incubation. The mean number of pores was significantly lower, and the mean interpore distance and the mean interpore area were significantly larger than those for mock-infected cells 15 h after inoculation. Forty-five percent of nuclear pores in HSV-1-infected cells were dilated to more than 140 nm. Nuclear material containing capsids protrude through them into the cytoplasm. Examination of in situ preparations after dry fracturing revealed significant enlargements of the nuclear pore diameter and of the nuclear pore central channel in HSV-1-infected cells compared to mock-infected cells. The demonstration of nucleoporins by confocal microscopy also revealed fewer pores but focal enhancement of fluorescence signals in HSV-1-infected cells, whereas Western blots showed no loss of nucleoporins from cells. The data suggest that infection with HSV-1 alters the number, size, and architecture of nuclear pores without a loss of nucleoporins from altered nuclear pore complexes.

scholarly journals Bidirectional Increase in Permeability of Nuclear Envelope upon Poliovirus Infection and Accompanying Alterations of Nuclear Pores

2004 ◽  
Vol 78 (18) ◽  
pp. 10166-10177 ◽  
Author(s):  
George A. Belov ◽  
Peter V. Lidsky ◽  
Olga V. Mikitas ◽  
Denise Egger ◽  
Konstantin A. Lukyanov ◽  
...  
Keyword(s):  
Nuclear Envelope ◽  
Nuclear Protein ◽  
Fluorescent Protein ◽  
Cyclin B1 ◽  
Nuclear Proteins ◽  
Nuclear Pores ◽  
Poliovirus Infection ◽  
Localization Signal ◽  
Infected Cells ◽  
Green Fluorescent

ABSTRACT Poliovirus and some other picornaviruses trigger relocation of certain nuclear proteins into the cytoplasm. Here, by using a protein changing its fluorescence color with time and containing a nuclear localization signal (NLS), we demonstrate that the poliovirus-triggered relocation is largely due to the exit of presynthesized nuclear protein into the cytoplasm. The leakiness of the nuclear envelope was also documented by the inability of nuclei from digitonin-permeabilized, virus-infected (but not mock-infected) cells to retain an NLS-containing derivative of green fluorescent protein (GFP). The cytoplasm-to-nucleus traffic was also facilitated during infection, as evidenced by experiments with GAPDH (glyceraldehyde-3-phosphate dehydrogenase), cyclin B1, and an NLS-lacking derivative of GFP, which are predominantly cytoplasmic in uninfected cells. Electron microscopy demonstrated that a bar-like barrier structure in the channel of the nuclear pores, seen in uninfected cells, was missing in the infected cells, giving the impression of fully open pores. Transient expression of poliovirus 2A protease also resulted in relocation of the nuclear proteins. Lysates from poliovirus-infected or 2A-expressing cells induced efflux of 3×EGFP-NLS from the nuclei of permeabilized uninfected cells. This activity was inhibited by the elastase inhibitors elastatinal and N-(methoxysuccinyl)-l-alanyl-l-alanyl-l-prolyl-l-valine chloromethylketone (drugs known also to be inhibitors of poliovirus protease 2A), a caspase inhibitor zVAD(OMe), fmk, and some other protease inhibitors. These data suggest that 2A elicited nuclear efflux, possibly in cooperation with a zVAD(OMe).fmk-sensitive protease. However, poliovirus infection facilitated nuclear protein efflux also in cells deficient in caspase-3 and caspase-9, suggesting that the efflux may occur without the involvement of these enzymes. The biological relevance of nucleocytoplasmic traffic alterations in infected cells is discussed.

scholarly journals Quantifying the unquantifiable: why Hymenoptera – not Coleoptera – is the most speciose animal order

2018 ◽  
Author(s):  
Andrew A. Forbes ◽  
Robin K. Bagley ◽  
Marc A. Beer ◽  
Alaine C. Hippee ◽  
Heather A. Widmayer
Keyword(s):  
Host Species ◽  
Parasitic Wasp ◽  
Parasitoid Wasps ◽  
Beetle Species ◽  
Insect Host ◽  
Parasitic Wasps ◽  
Logical Model ◽  
Wasp Species

AbstractBackgroundWe challenge the oft-repeated claim that the beetles (Coleoptera) are the most species-rich order of animals. Instead, we assert that another order of insects, the Hymenoptera, are more speciose, due in large part to the massively diverse but relatively poorly known parasitoid wasps. The idea that the beetles have more species than other orders is primarily based on their respective collection histories and the relative availability of taxonomic resources, which both disfavor parasitoid wasps. Though it is unreasonable to directly compare numbers of described species in each order, the ecology of parasitic wasps – specifically, their intimate interactions with their hosts – allows for estimation of relative richness. We present a simple logical model that shows how the specialization of many parasitic wasps on their hosts suggests few scenarios in which there would be more beetle species than parasitic wasp species. We couple this model with an accounting of what we call the “genus-specific parasitoid-host ratio” from four well-studied genera of insect hosts, a metric by which to generate extremely conservative estimates of the average number of parasitic wasp species attacking a given beetle or other insect host species. Synthesis of our model with data from real host systems suggests that the Hymenoptera may have 2.5 - 3.2× more species than the Coleoptera. While there are more described species of beetles than all other animals, the Hymenoptera are almost certainly the larger order.

scholarly journals Effects of Charged Cluster Mutations on the Function of Herpes Simplex Virus Type 1 UL34 Protein

2003 ◽  
Vol 77 (13) ◽  
pp. 7601-7610 ◽  
Author(s):  
Susan L. Bjerke ◽  
John M. Cowan ◽  
Jelani K. Kerr ◽  
Ashley E. Reynolds ◽  
Joel D. Baines ◽  
...  
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Infected Cell ◽  
Nuclear Envelope ◽  
Herpes Simplex Virus Type ◽  
Wild Type ◽  
Charged Cluster ◽  
Infected Cells ◽  
Simplex Virus

ABSTRACT Herpes simplex virus type 1 (HSV-1) is a DNA virus that acquires an envelope by budding into the inner nuclear membrane of an infected cell. Recombinant HSV-1 lacking the UL34 gene cannot undergo this event. UL34 and UL31, another viral protein, colocalize in an infected cell and are necessary and sufficient to target both proteins to the inner nuclear envelope. In order to define and characterize sequences of UL34 that are necessary for primary envelopment to occur, a library of 19 UL34 charged cluster mutants and a truncation mutant lacking the putative transmembrane domain (ΔTM) were generated. Mutants in this library were analyzed in a complementation assay for their ability to function in the production of infectious virus. Seven of the mutants failed to complement a UL34-null virus. The remainder of the mutants complemented at or near wild-type UL34 levels. Failure of a mutant protein to function might be the result of incorrect subcellular localization. To address this possibility, confocal microscopy was used to determine the localization of the UL34 protein in charged cluster mutants and ΔTM. In transfection-infection experiments, all of the functional UL34 mutants and four of the six noncomplementing mutants localized to the inner nuclear envelope in a manner indistinguishable from that of wild-type UL34. All of the noncomplementing UL34 mutants mediated proper localization of UL31. Charged clusters critical for UL34 function are dispersed throughout the protein sequence and do not correlate well with highly conserved regions of the protein. These data suggest that UL34 has at least one function in addition to mediating proper localization of UL31 in infected cells and provide further support for the role of UL34 in mediating proper localization of UL31 in infected cells.

scholarly journals Involvement of Golgi apparatus and a restructured nuclear envelope during biogenesis and transport of herpes simplex virus glycoproteins.

1985 ◽  
Vol 33 (9) ◽  
pp. 875-883 ◽  
Author(s):  
L Poliquin ◽  
G Levine ◽  
G C Shore
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Golgi Apparatus ◽  
Nuclear Envelope ◽  
Nuclear Membranes ◽  
Viral Particles ◽  
Infected Cells ◽  
Simplex Virus ◽  
Hsv 1

Following infection of BHK-21 cells with Herpes simplex virus type 1 (HSV-1), progeny nucleocapsids in the nucleus acquire a glycoprotein-rich envelope by budding through host-cell nuclear membranes. To investigate the nature of the glycoprotein products assembled in the virion at the nuclear envelope, infected cells were pulse-labeled with [3H]-mannose, an oligosaccharidal core sugar, or [3H]-fucose, a terminal sugar. After various chase periods, the incorporation of these sugars was monitored by electron microscope radioautography. The results show that HSV glycoproteins accumulate very rapidly in nuclear membranes, where they exist only as core-glycosylated precursors, i.e., containing [3H]-mannose but not [3H]-fucose. [3H]-fucose grains are seen mainly over Golgi membranes and over virions located in the Golgi and in other cytoplasmic vesicular structures. Our data support a model where addition of terminal sugars (e.g., fucose) to HSV-1 glycoprotein precursors can occur at the surface of newly enveloped viral particles as the virions themselves egress from the cell via the Golgi apparatus.

scholarly journals Mengovirus-Induced Rearrangement of the Nuclear Pore Complex: Hijacking Cellular Phosphorylation Machinery

2009 ◽  
Vol 83 (7) ◽  
pp. 3150-3161 ◽  
Author(s):  
Maryana V. Bardina ◽  
Peter V. Lidsky ◽  
Eugene V. Sheval ◽  
Ksenia V. Fominykh ◽  
Frank J. M. van Kuppeveld ◽  
...  
Keyword(s):  
Nuclear Envelope ◽  
Nuclear Pore Complex ◽  
Biological Significance ◽  
Nucleocytoplasmic Transport ◽  
Nuclear Pore ◽  
Wild Type ◽  
Nuclear Pores ◽  
Infected Cells ◽  
Protein Components ◽  
Bidirectional Exchange

ABSTRACT Representatives of several picornavirus genera have been shown previously to significantly enhance noncontrollable bidirectional exchange of proteins between nuclei and cytoplasm. In enteroviruses and rhinoviruses, enhanced permeabilization of the nuclear pores appears to be primarily due to proteolytic degradation of some nucleoporins (protein components of the pore), whereas this effect in cardiovirus-infected cells is triggered by the leader (L) protein, devoid of any enzymatic activities. Here, we present evidence that expression of L alone was sufficient to cause permeabilization of the nuclear envelope in HeLa cells. In contrast to poliovirus, mengovirus infection of these cells did not elicit loss of nucleoporins Nup62 and Nup153 from the nuclear pore complex. Instead, nuclear envelope permeabilization was accompanied by hyperphosphorylation of Nup62 in cells infected with wild-type mengovirus, whereas both of these alterations were suppressed in L-deficient virus mutants. Since phosphorylation of Nup62 (although less prominent) did accompany permeabilization of the nuclear envelope prior to its mitotic disassembly in uninfected cells, we hypothesize that cardiovirus L alters the nucleocytoplasmic traffic by hijacking some components of the normal cell division machinery. The variability and biological significance of picornaviral interactions with the nucleocytoplasmic transport in the infected cells are discussed.

Sign in / Sign up

Export Citation Format

Share Document