scholarly journals Adenovirus Type 5 E4orf3 Protein Targets the Mre11 Complex to Cytoplasmic Aggresomes

2005 ◽  
Vol 79 (17) ◽  
pp. 11382-11391 ◽  
Author(s):  
Felipe D. Araujo ◽  
Travis H. Stracker ◽  
Christian T. Carson ◽  
Darwin V. Lee ◽  
Matthew D. Weitzman
Keyword(s):  
Morphological Characteristics ◽  
Adenovirus Type ◽  
Nuclear Bodies ◽  
Virus Infections ◽  
Cytoplasmic Inclusions ◽  
Reading Frame ◽  
Mre11 Complex ◽  
Efficient Replication ◽  
Serotype 5 ◽  
Cellular Dna

ABSTRACT Virus infections have dramatic effects on structural and morphological characteristics of the host cell. The gene product of open reading frame 3 in the early region 4 (E4orf3) of adenovirus serotype 5 (Ad5) is involved in efficient replication and late protein synthesis. During infection with adenovirus mutants lacking the E4 region, the viral genomic DNA is joined into concatemers by cellular DNA repair factors, and this requires the Mre11/Rad50/Nbs1 complex. Concatemer formation can be prevented by the E4orf3 protein, which causes the cellular redistribution of the Mre11 complex. Here we show that E4orf3 colocalizes with components of the Mre11 complex in nuclear tracks and also in large cytoplasmic accumulations. Rearrangement of Mre11 and Rad50 by Ad5 E4orf3 is not dependent on interactions with Nbs1 or promyelocytic leukemia protein nuclear bodies. Late in infection the cytoplasmic inclusions appear as a distinct juxtanuclear accumulation at the centrosome and this requires an intact microtubule cytoskeleton. The large cytoplasmic accumulations meet the criteria defined for aggresomes, including γ-tubulin colocalization and formation of a surrounding vimentin cage. E4orf3 also appears to alter the solubility of the cellular Mre11 complex. These data suggest that E4orf3 can target the Mre11 complex to an aggresome and may explain how the cellular repair complex is inactivated during adenovirus infection.

Vector expression of adenovirus type 5 E1a proteins: evidence for E1a autoregulation

1985 ◽  
Vol 5 (10) ◽  
pp. 2684-2696
Author(s):  
D H Smith ◽  
D M Kegler ◽  
E B Ziff
Keyword(s):  
Amino Acid ◽  
Simian Virus 40 ◽  
Adenovirus Type ◽  
Simian Virus ◽  
Mutant Form ◽  
Amino Acid Residues ◽  
Reading Frame ◽  
Acid Protein ◽  
Dna Replication Origin ◽  
E1a Protein

We transiently expressed adenovirus type C E1a proteins in wild-type or mutant form from plasmid vectors which have different combinations of E1a and simian virus 40 enhancer elements and which contain the DNA replication origin of SV40 and can replicate in COS 7 cells. We measured the levels of E1a mRNA encoded by the vectors and the transition regulation properties of the protein products. Three vectors encoded equivalent levels of E1a mRNA in COS 7 cells: (i) a plasmid encoding the wt 289-amino acid E1a protein (this complemented the E1a deletion mutant dl312 for early region E2a expression under both replicative and nonreplicative conditions); (ii) a vector for the wt 243-amino acid E1a protein (this complemented dl312 weakly and only under conditions of high multiplicities of dl312); (iii) a mutant, pSVXL105, in which amino acid residues-38 through 44 of the 289-amino acid E1a protein (which includes two highly conserved residues) are replaced by 3 novel amino acids (this also complemented dl312 efficiently). A fourth vector, mutant pSVXL3 with which linker substitution shifts the reading frame to encode a truncated 70-amino acid fragment from the amino terminus of the 289-amino acid protein, was unable to complement dl312. Surprisingly, pSVXL3 overexpressed E1a mRNA approximately 30-fold in COS 7 cells in comparison with the other vectors. The pSVXL3 overexpression could be reversed by cotransfection with a wt E1a vector. We suggest that wt E1a proteins regulate the levels of their own mRNAs through the recently described transcription repression functions of the 289- and 243-amino acid E1a protein products and that pSVXL3 fails to autoregulate negatively.

scholarly journals Adenovirus type 2 activates cell cycle-dependent genes that are a subset of those activated by serum.

1985 ◽  
Vol 5 (11) ◽  
pp. 2936-2942 ◽  
Author(s):  
H T Liu ◽  
R Baserga ◽  
W E Mercer
Keyword(s):  
Cell Cycle ◽  
Dna Synthesis ◽  
Thymidine Kinase ◽  
Histone H3 ◽  
Adenovirus Type ◽  
3T3 Cells ◽  
Cycle Dependent ◽  
Cellular Dna ◽  
Adenovirus Type 2

We have studied a panel of 10 genes and cDNA sequences that are expressed in a cell cycle-dependent manner in different types of cells from different species and that are inducible by different mitogens. These include five sequences (c-myc, 4F1, 2F1, 2A9, and KC-1) that are preferentially expressed in the early part of the G1 phase, three genes (ornithine decarboxylase, p53, and c-rasHa) preferentially expressed in middle or late G1, and two genes (thymidine kinase and histone H3) preferentially expressed in the S phase of the cell cycle. We have studied the expression of these genes in nonpermissive (tsAF8) and semipermissive (Swiss 3T3) cells infected with adenovirus type 2. Under the conditions of these experiments, adenovirus type 2 infection stimulates cellular DNA synthesis in both tsAF8 and 3T3 cells. However, four of the five early G1 genes (c-myc, 4F1, KC-1, and 2A9) and one of the late G1 genes (c-ras) are not induced by adenovirus infection, although they are strongly induced by serum. The other sequences (2F1, ornithine decarboxylase, p53, thymidine kinase, and histone H3) are activated by both adenovirus and serum. We conclude that the cell cycle-dependent genes activated by adenovirus 2 are a subset of the cell cycle-dependent genes activated by serum. The data suggest that the mechanisms by which serum and adenovirus induce cellular DNA synthesis are not identical.

scholarly journals Murine Gammaherpesvirus 68 Open Reading Frame 75c Tegument Protein Induces the Degradation of PML and Is Essential for Production of Infectious Virus

2008 ◽  
Vol 82 (16) ◽  
pp. 8000-8012 ◽  
Author(s):  
Paul D. Ling ◽  
Jie Tan ◽  
Jaturong Sewatanon ◽  
RongSheng Peng
Keyword(s):  
Infectious Virus ◽  
Nuclear Body ◽  
Tegument Protein ◽  
Suitable Model ◽  
Virus Infections ◽  
Reading Frame ◽  
Murine Gammaherpesvirus ◽  
Gammaherpesvirus 68 ◽  
Murine Gammaherpesvirus 68

ABSTRACT Promyelocytic Leukemia nuclear body (PML NB) proteins mediate an intrinsic cellular host defense response against virus infections. Herpesviruses express proteins that modulate PML or PML-associated proteins by a variety of strategies, including degradation of PML or relocalization of PML NB proteins. The consequences of PML-herpesvirus interactions during infection in vivo have yet to be investigated in detail, largely because of the species-specific tropism of many human herpesviruses. Murine gammaherpesvirus 68 (γHV68) is emerging as a suitable model to study basic biological questions of virus-host interactions because it naturally infects mice. Therefore, we sought to determine whether γHV68 targets PML NBs as part of its natural life cycle. We found that γHV68 induces PML degradation through a proteasome-dependent mechanism and that loss of PML results in more robust virus replication in mouse fibroblasts. Surprisingly, γHV68-mediated PML degradation was mediated by the virion tegument protein ORF75c, which shares homology with the cellular formylglycinamide ribotide amidotransferase enzyme. In addition, we show that ORF75c is essential for production of infectious virus. ORF75 homologs are conserved in all rhadinoviruses but so far have no assigned functions. Our studies shed light on a potential role for this unusual protein in rhadinovirus biology and suggest that γHV68 will be a useful model for investigation of PML-herpesvirus interactions in vivo.

Adenovirus type 2 activates cell cycle-dependent genes that are a subset of those activated by serum

1985 ◽  
Vol 5 (11) ◽  
pp. 2936-2942
Author(s):  
H T Liu ◽  
R Baserga ◽  
W E Mercer
Keyword(s):  
Cell Cycle ◽  
Dna Synthesis ◽  
Thymidine Kinase ◽  
Histone H3 ◽  
Adenovirus Type ◽  
3T3 Cells ◽  
Cycle Dependent ◽  
Cellular Dna ◽  
Adenovirus Type 2

We have studied a panel of 10 genes and cDNA sequences that are expressed in a cell cycle-dependent manner in different types of cells from different species and that are inducible by different mitogens. These include five sequences (c-myc, 4F1, 2F1, 2A9, and KC-1) that are preferentially expressed in the early part of the G1 phase, three genes (ornithine decarboxylase, p53, and c-rasHa) preferentially expressed in middle or late G1, and two genes (thymidine kinase and histone H3) preferentially expressed in the S phase of the cell cycle. We have studied the expression of these genes in nonpermissive (tsAF8) and semipermissive (Swiss 3T3) cells infected with adenovirus type 2. Under the conditions of these experiments, adenovirus type 2 infection stimulates cellular DNA synthesis in both tsAF8 and 3T3 cells. However, four of the five early G1 genes (c-myc, 4F1, KC-1, and 2A9) and one of the late G1 genes (c-ras) are not induced by adenovirus infection, although they are strongly induced by serum. The other sequences (2F1, ornithine decarboxylase, p53, thymidine kinase, and histone H3) are activated by both adenovirus and serum. We conclude that the cell cycle-dependent genes activated by adenovirus 2 are a subset of the cell cycle-dependent genes activated by serum. The data suggest that the mechanisms by which serum and adenovirus induce cellular DNA synthesis are not identical.

scholarly journals Viral Factors Important for Efficient Replication of Influenza A Viruses in Cells of the Central Nervous System

2019 ◽  
Vol 93 (11) ◽  
Author(s):  
Jurre Y. Siegers ◽  
Marco W. G. van de Bildt ◽  
Zhanmin Lin ◽  
Lonneke M. Leijten ◽  
Rémon A. M. Lavrijssen ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Influenza A ◽  
H5n1 Virus ◽  
Influenza Viruses ◽  
Virus Infections ◽  
Influenza A Viruses ◽  
Cns Disease ◽  
Efficient Replication ◽  
Hpai H5n1 ◽  
In Cells

ABSTRACTCentral nervous system (CNS) disease is one of the most common extrarespiratory tract complications of influenza A virus infections. Remarkably, zoonotic H5N1 virus infections are more frequently associated with CNS disease than seasonal or pandemic influenza viruses. Little is known about the interaction between influenza A viruses and cells of the CNS; therefore, it is currently unknown which viral factors are important for efficient replication. Here, we determined the replication kinetics of a seasonal, pandemic, zoonotic, and lab-adapted influenza A virus in human neuron-like (SK-N-SH) and astrocyte-like (U87-MG) cells and primary mouse cortex neurons. In general, highly pathogenic avian influenza (HPAI) H5N1 virus replicated most efficiently in all cells, which was associated with efficient attachment and infection. Seasonal H3N2 and to a lesser extent pandemic H1N1 virus replicated in a trypsin-dependent manner in SK-N-SH but not in U87-MG cells. In the absence of trypsin, only HPAI H5N1 and WSN viruses replicated. Removal of the multibasic cleavage site (MBCS) from HPAI H5N1 virus attenuated, but did not abrogate, replication. Taken together, our results showed that the MBCS and, to a lesser extent, the ability to attach are important determinants for efficient replication of HPAI H5N1 virus in cells of the CNS. This suggests that both an alternative hemagglutinin (HA) cleavage mechanism and preference for α-2,3-linked sialic acids allowing efficient attachment contribute to the ability of influenza A viruses to replicate efficiently in cells of the CNS. This study further improves our knowledge on potential viral factors important for the neurotropic potential of influenza A viruses.IMPORTANCECentral nervous system (CNS) disease is one of the most common extrarespiratory tract complications of influenza A virus infections, and the frequency and severity differ between seasonal, pandemic, and zoonotic influenza viruses. However, little is known about the interaction of these viruses with cells of the CNS. Differences among seasonal, pandemic, and zoonotic influenza viruses in replication efficacy in CNS cells,in vitro, suggest that the presence of an alternative HA cleavage mechanism and ability to attach are important viral factors. Identifying these viral factors and detailed knowledge of the interaction between influenza virus and CNS cells are important to prevent and treat this potentially lethal CNS disease.

Maintenance of primary African green monkey kidney (pAGMK) and Vero cells at room temperature (25°). A system for virus isolation in community practice

1974 ◽  
Vol 20 (3) ◽  
pp. 391-397 ◽  
Author(s):  
Julius A. A. Mingle ◽  
J. C. N. Westwood
Keyword(s):  
Herpes Simplex ◽  
Room Temperature ◽  
Adenovirus Type ◽  
Field Studies ◽  
Vero Cells ◽  
Community Practice ◽  
Virus Infections ◽  
African Green Monkey Kidney ◽  
Before And After ◽  
Simplex Virus

Primary AGMK cells and Vero cells were maintained at room temperature (25 °C) and their sensitivities tested using echovirus type 9, coxsackie B4 and B5, herpes simplex virus, vaccinia, influenza A2/Hong Kong, and adenovirus type 7. pAGMK maintained for 4 days at room temperature was found to be less sensitive to herpes simplex and coxsackie B4 whilst maintenance of Vero cells at room temperature did not affect the sensitivity. Susceptibility of these two cell cultures to prototype viruses indicated that pAGMK was more susceptible.pAGMK cells were held at room temperature both before and after inoculation with viruses and incubated at 37 °C. Cytopathic effect (CPE) was noticed in these cells earlier after switching them to 37 °C incubation than when refrigerated suspensions of the viruses were inoculated into fresh cultures that had not been subjected to room temperature incubation. The usefulness of such a procedure in field studies of virus infections is discussed.

scholarly journals The Adenovirus E4 ORF3 Protein Binds and Reorganizes the TRIM Family Member Transcriptional Intermediary Factor 1 Alpha

2007 ◽  
Vol 81 (8) ◽  
pp. 4264-4271 ◽  
Author(s):  
Mark A. Yondola ◽  
Patrick Hearing
Keyword(s):  
Family Member ◽  
Protein Interactions ◽  
Coiled Coil ◽  
Ring Finger ◽  
Nuclear Bodies ◽  
Reading Frame ◽  
Orf3 Protein ◽  
Proteomic Approach ◽  
Evolutionarily Conserved ◽  
Trim Proteins

ABSTRACT One of the most interesting functions attributed to the adenovirus early region 4 open reading frame 3 (E4 ORF3) protein is its reorganization of promyelocytic leukemia (PML) protein nuclear bodies. These normally punctate structures are reorganized by E4 ORF3 into tracks that eventually surround viral replication centers. PML rearrangement is an evolutionarily conserved function of E4 ORF3, yet its cause and functional relevance remain mysteries. The E4 ORF3 protein coimmunoprecipitates with the PML protein, yet E4 ORF3 still forms tracks in cells that lack PML. The PML protein is a member of a larger protein family termed tripartite motif (TRIM) proteins. TRIM proteins contain a tripartite domain structure in proximity to their N termini that consists of a RING finger domain, followed by one or two B box domains and a C-terminal coiled-coil domain (collectively termed the RBCC domain). The order and spacing of these domains are evolutionarily conserved and thought to mediate protein-protein interactions and other functions. We implemented a proteomic approach to isolate cellular proteins that bind to E4 ORF3. We identified a novel interaction between E4 ORF3 and another TRIM family member, transcriptional intermediary factor 1 alpha (TIF1α). TIF1α functions by recruiting coactivators and/or corepressors to modulate transcription. The interaction between E4 ORF3 and TIF1α was validated by coimmunoprecipitation and binding of recombinant proteins. Indirect immunofluorescence assays demonstrated that TIF1α is reorganized into track structures that contain PML upon E4 ORF3 expression. The RBCC domain of TIF1α is sufficient for E4 ORF3-induced rearrangement, and TIF1α reorganization is conserved across adenovirus serotypes.

p14ARF inhibits the functions of adenovirus E1A oncoprotein

2011 ◽  
Vol 434 (2) ◽  
pp. 275-285 ◽  
Author(s):  
Jia Shen ◽  
Shengping Zhang ◽  
Yang Li ◽  
Wen Zhang ◽  
Jiandong Chen ◽  
...  
Keyword(s):  
Host Cells ◽  
Inhibitory Interaction ◽  
Reading Frame ◽  
Binding Partner ◽  
Adenovirus E1a ◽  
Stress Sensors ◽  
Murine Double Minute ◽  
Cellular Dna ◽  
Fine Tune ◽  
Oncogenic Stress

The tumour suppressor ARF (alternative reading frame) is one of the most important oncogenic stress sensors. ARF provides an ‘oncogenic checkpoint’ function through both p53-dependent and p53-independent mechanisms. In the present study, we demonstrate a novel p53-independent interaction between p14ARF and the adenovirus oncoprotein E1A. p14ARF inhibits E1A transcriptional function and promotes ubiquitination-dependent degradation of E1A. p14ARF overexpression relocalizes E1A into the nucleolus and inhibits E1A-induced cellular DNA replication independent of p53. Knockdown of endogenous p14ARF increases E1A transactivation. In addition, E1A can competitively inhibit ARF–Mdm2 (murine double minute 2) complex formation. These results identify a novel binding partner of p14ARF and reveal a mutually inhibitory interaction between p14ARF and E1A. We speculate that the ARF–E1A interaction may represent an additional host defence mechanism to limit viral replication. Alternatively, the interaction may allow adenovirus to sense the functional state of p53 in host cells, and fine-tune its own replication activity to prevent the triggering of a detrimental host response.

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