scholarly journals Control of adenovirus early gene expression: posttranscriptional control mediated by both viral and cellular gene products.

1981 ◽  
Vol 1 (9) ◽  
pp. 807-813 ◽  
Author(s):  
M G Katze ◽  
H Persson ◽  
L Philipson
Keyword(s):  
Gene Product ◽  
Messenger Rna ◽  
Adenovirus Type ◽  
Negative Regulator ◽  
Early Gene ◽  
In Vitro Translation ◽  
Mapping Technique ◽  
Cellular Gene ◽  
Infected Cells ◽  
Adenovirus Type 5

An adenovirus type 5 host range mutant (hr-1) located in region E1A and phenotypically defective in expressing viral messenger ribonucleic acid (RNA) from other early regions (Berk et al., Cell 17:935-944, 1979) was analyzed for accumulation of viral RNA in the presence of protein synthesis inhibitors. Nuclear RNA was transcribed from all early regions at the same rate, regardless of whether the drug was present or absent. As expected, low or undetectable levels of RNA were found in the cytoplasm of hr-1-infected cells compared with the wild-type adenovirus type 5 in the absence of drug. When anisomycin was added 30 min before hr-1 infection, cytoplasmic RNA was abundant from early regions E3 and E4 when assayed by filter hybridization. In accordance, early regions E3 and E4 viral messenger RNA species were detected by the S1 endonuclease mapping technique only in hr-1-infected cells that were treated with the drug. Similar results were obtained by in vitro translation studies. Together, these results suggest that this adenovirus type 5 mutant lacks a viral gene product necessary for accumulation of viral messenger RNA, but not for transcription. It is proposed that a cellular gene product serves as a negative regulator of viral messenger RNA accumulation at the posttranscriptional level.

Control of adenovirus early gene expression: posttranscriptional control mediated by both viral and cellular gene products

1981 ◽  
Vol 1 (9) ◽  
pp. 807-813
Author(s):  
M G Katze ◽  
H Persson ◽  
L Philipson
Keyword(s):  
Gene Product ◽  
Messenger Rna ◽  
Adenovirus Type ◽  
Negative Regulator ◽  
Early Gene ◽  
In Vitro Translation ◽  
Mapping Technique ◽  
Cellular Gene ◽  
Infected Cells ◽  
Adenovirus Type 5

An adenovirus type 5 host range mutant (hr-1) located in region E1A and phenotypically defective in expressing viral messenger ribonucleic acid (RNA) from other early regions (Berk et al., Cell 17:935-944, 1979) was analyzed for accumulation of viral RNA in the presence of protein synthesis inhibitors. Nuclear RNA was transcribed from all early regions at the same rate, regardless of whether the drug was present or absent. As expected, low or undetectable levels of RNA were found in the cytoplasm of hr-1-infected cells compared with the wild-type adenovirus type 5 in the absence of drug. When anisomycin was added 30 min before hr-1 infection, cytoplasmic RNA was abundant from early regions E3 and E4 when assayed by filter hybridization. In accordance, early regions E3 and E4 viral messenger RNA species were detected by the S1 endonuclease mapping technique only in hr-1-infected cells that were treated with the drug. Similar results were obtained by in vitro translation studies. Together, these results suggest that this adenovirus type 5 mutant lacks a viral gene product necessary for accumulation of viral messenger RNA, but not for transcription. It is proposed that a cellular gene product serves as a negative regulator of viral messenger RNA accumulation at the posttranscriptional level.

Genomic footprinting detects factors bound to major late and IVa2 promoters in adenovirus-infected HeLa cells

1988 ◽  
Vol 8 (4) ◽  
pp. 1534-1539
Author(s):  
G Albrecht ◽  
B Devaux ◽  
C Kedinger
Keyword(s):  
Protein Interactions ◽  
Adenovirus Type ◽  
Nuclease Activity ◽  
Dnase I ◽  
Promoter Activation ◽  
Promoter Elements ◽  
Dnase I Footprinting ◽  
Infected Cells ◽  
Adenovirus Type 5

We used DNase I footprinting assays on nuclei isolated from adenovirus-infected cells to examine the nucleoprotein configuration of a 250-base-pair segment which encompasses the adenovirus type 5 major late (ML) and IVa2 promoters. At 12 and 20 h postinfection (p.i.), fine DNase I digestion mapping of wild-type adenovirus-infected cells revealed specific sequences protected from digestion which corresponded to promoter elements required for expression of the ML gene in vivo. At 12 h p.i., a G+C-rich region which lies upstream of the IVa2 cap site and is important for maximal IVa2 activity was also found masked to nuclease activity. At 20 h p.i., however, this element became more sensitive to nuclease attack, while the ML promoter elements stayed protected. No major changes in DNA-protein interactions were detected in the region spanning the ML and IVa2 cap sites upon promoter activation, suggesting that the binding properties of the cognate factors for this region are not modified during the process.

scholarly journals Genomic footprinting detects factors bound to major late and IVa2 promoters in adenovirus-infected HeLa cells.

1988 ◽  
Vol 8 (4) ◽  
pp. 1534-1539 ◽  
Author(s):  
G Albrecht ◽  
B Devaux ◽  
C Kedinger
Keyword(s):  
Protein Interactions ◽  
Adenovirus Type ◽  
Nuclease Activity ◽  
Dnase I ◽  
Promoter Activation ◽  
Promoter Elements ◽  
Dnase I Footprinting ◽  
Infected Cells ◽  
Adenovirus Type 5

We used DNase I footprinting assays on nuclei isolated from adenovirus-infected cells to examine the nucleoprotein configuration of a 250-base-pair segment which encompasses the adenovirus type 5 major late (ML) and IVa2 promoters. At 12 and 20 h postinfection (p.i.), fine DNase I digestion mapping of wild-type adenovirus-infected cells revealed specific sequences protected from digestion which corresponded to promoter elements required for expression of the ML gene in vivo. At 12 h p.i., a G+C-rich region which lies upstream of the IVa2 cap site and is important for maximal IVa2 activity was also found masked to nuclease activity. At 20 h p.i., however, this element became more sensitive to nuclease attack, while the ML promoter elements stayed protected. No major changes in DNA-protein interactions were detected in the region spanning the ML and IVa2 cap sites upon promoter activation, suggesting that the binding properties of the cognate factors for this region are not modified during the process.

scholarly journals The adenovirus E1B-55K transforming polypeptide modulates transport or cytoplasmic stabilization of viral and host cell mRNAs.

1986 ◽  
Vol 6 (2) ◽  
pp. 470-476 ◽  
Author(s):  
S Pilder ◽  
M Moore ◽  
J Logan ◽  
T Shenk
Keyword(s):  
Hela Cells ◽  
Adenovirus Type ◽  
Transcription Unit ◽  
Early Gene ◽  
Wild Type Virus ◽  
Wild Type ◽  
Coding Region ◽  
Viral Mrnas ◽  
Cellular Mrnas ◽  
Adenovirus Type 5

The adenovirus type 5 mutant H5dl338 lacks 524 base pairs within early region 1B. The mutation removed a portion of the region encoding the related E1B-55K and -17K polypeptides but did not disturb the E1B-21K coding region. The virus can be propagated in 293 cells which contain and express the adenovirus type 5 E1A and E1B regions, but it is defective for growth in HeLa cells, in which its final yield is reduced about 100-fold compared with the wild-type virus. The mutant also fails to transform rat cells at normal efficiency. The site of the dl338 defect was studied in HeLa cells. Early gene expression and DNA replication appeared normal. Late after infection, mRNAs coded by the major late transcription unit accumulated to reduced levels. At a time when transcription rates and steady-state nuclear RNA species were normal, the rate at which late mRNA accumulated in the cytoplasm was markedly reduced. Furthermore, in contrast to the case with the wild type, transport and accumulation of cellular mRNAs continued late after infection with dl338. Thus, the E1B product appears to facilitate transport and accumulation of viral mRNAs late after infection while blocking the same processes for cellular mRNAs.

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 Adenovirus Type 5 E4orf3 Protein Relieves p53 Inhibition by E1B-55-Kilodalton Protein

1999 ◽  
Vol 73 (3) ◽  
pp. 2253-2262 ◽  
Author(s):  
Claudia König ◽  
Judith Roth ◽  
Matthias Dobbelstein
Keyword(s):  
Gene Product ◽  
Transcriptional Activity ◽  
Adenovirus Type ◽  
Suppressor Gene ◽  
Promyelocytic Leukemia ◽  
Wild Type ◽  
P53 Tumor Suppressor Gene ◽  
Tumor Suppressor Gene Product ◽  
Nuclear Structures ◽  
Adenovirus Type 5

ABSTRACT The E1B-55-kDa protein of adenovirus type 5 and the p53 tumor suppressor gene product form a complex that localizes to the cytoplasm, thereby downregulating p53’s transcriptional activity. The E4orf6 protein binds and relocalizes E1B-55-kDa, and the proteins act synergistically to inactivate p53. We show that another adenovirus E4 gene product, E4orf3, is also sufficient to relocalize E1B-55-kDa from the cytoplasm to the nucleus. Both proteins are then found in discrete nuclear structures (tracks) that are known to contain components of the promyelocytic leukemia-associated nuclear structure. Simultaneously, p53 is dissociated from E1B-55-kDa and is found evenly distributed over the nucleoplasm. In the presence of E4orf3, p53-dependent transcriptional activity is no longer repressed by E1B-55-kDa. When E1B-55-kDa is coexpressed with E4orf3 and E4orf6, E1B-55-kDa is found to colocalize with E4orf6 rather than E4orf3. In parallel, p53 is inhibited and degraded by the combination of E1B-55-kDa and E4orf6, regardless of coexpressed E4orf3. This suggests that the effects of E4orf6 on E1B-55-kDa overrule the actions of E4orf3. When cells are infected with virus expressing E4orf3 but not E4orf6, E1B is found in the cell nucleus and p53 enters the virus replication centers. After infection with wild-type adenovirus, E4orf3 is expressed before E4orf6 and E1B temporarily colocalizes with E4orf3 in nuclear tracks before associating with E4orf6. We propose that during adenovirus infection, the E4orf3 protein transiently liberates p53 from its association with E1B-55-kDa. Subsequently, p53 is inactivated and degraded by the combination of E1B-55-kDa and E4orf6.

scholarly journals Gene product of region E4 of adenovirus type 5 modulates accumulation of certain viral polypeptides.

1988 ◽  
Vol 62 (9) ◽  
pp. 3258-3264 ◽  
Author(s):  
C Hemström ◽  
K Nordqvist ◽  
U Pettersson ◽  
A Virtanen
Keyword(s):  
Gene Product ◽  
Adenovirus Type ◽  
Adenovirus Type 5

scholarly journals E2F from adenovirus-infected cells binds cooperatively to DNA containing two properly oriented and spaced recognition sites.

1989 ◽  
Vol 9 (10) ◽  
pp. 4495-4506 ◽  
Author(s):  
S Hardy ◽  
T Shenk
Keyword(s):  
Uninfected Cell ◽  
Adenovirus Type ◽  
Relative Orientation ◽  
Multiple Forms ◽  
Adenovirus E1a ◽  
Cell Extracts ◽  
Binding Factor ◽  
Infected Cells ◽  
Transcriptional Start Sites ◽  
Adenovirus Type 5

E2F is a sequence-specific DNA-binding factor which binds to sites that occur in pairs upstream of the adenovirus E1A and E2 early transcriptional start sites. Substantial quantities of E2F activity were found in uninfected-cell extracts, and there was a modest increase in E2F activity during an adenovirus type 5 (Ad5) infection. In uninfected cells, E2F was found to exist in multiple forms that could be separated chromatographically. Extracts prepared at 24 h after Ad5 infection contained a new form of E2F. This infection-specific form may have been a modified version of one of the forms present in uninfected cells. The infection-specific E2F was shown to bind cooperatively to a pair of E2F sites found upstream of the Ad2 early region 2 mRNA cap site. This binding was sensitive to the spacing between the sites and their relative orientation. In contrast, E2F binding in uninfected-cell extracts was unaffected by changes in orientation and spacing, consistent with very low cooperativity or independent binding.

Sign in / Sign up

Export Citation Format

Share Document