scholarly journals Establishment of the Human Papillomavirus Type 16 (HPV-16) Life Cycle in an Immortalized Human Foreskin Keratinocyte Cell Line

Virology ◽  
1999 ◽  
Vol 262 (2) ◽  
pp. 344-354 ◽  
Author(s):  
Elsa R. Flores ◽  
B.Lynn Allen-Hoffmann ◽  
Denis Lee ◽  
Carol A. Sattler ◽  
Paul F. Lambert
Keyword(s):  
Human Papillomavirus ◽  
Life Cycle ◽  
Cell Line ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Keratinocyte Cell

scholarly journals The Human Papillomavirus Type 16 E7 Oncogene Is Required for the Productive Stage of the Viral Life Cycle

2000 ◽  
Vol 74 (14) ◽  
pp. 6622-6631 ◽  
Author(s):  
Elsa R. Flores ◽  
B. Lynn Allen-Hoffmann ◽  
Denis Lee ◽  
Paul F. Lambert
Keyword(s):  
Human Papillomavirus ◽  
Life Cycle ◽  
Dna Replication ◽  
Epithelial Cells ◽  
Dna Synthesis ◽  
Copy Number ◽  
Keratinocyte Differentiation ◽  
Replication Machinery ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16

ABSTRACT The production of the human papillomavirus type 16 (HPV-16) is intimately tied to the differentiation of the host epithelium that it infects. Infection occurs in the basal layer of the epithelium at a site of wounding, where the virus utilizes the host DNA replication machinery to establish itself as a low-copy-number episome. The productive stage of the HPV-16 life cycle occurs in the postmitotic suprabasal layers of the epithelium, where the virus amplifies its DNA to high copy number, synthesizes the capsid proteins (L1 and L2), encapsidates the HPV-16 genome, and releases virion particles as the upper layer of the epithelium is shed. Papillomaviruses are hypothesized to possess a mechanism to overcome the block in DNA synthesis that occurs in the differentiated epithelial cells, and the HPV-16 E7 oncoprotein has been suggested to play a role in this process. To determine whether E7 plays a role in the HPV-16 life cycle, an E7-deficient HPV-16 genome was created by inserting a translational termination linker (TTL) in the E7 gene of the full HPV-16 genome. This DNA was transfected into an immortalized human foreskin keratinocyte cell line shown previously to support the HPV-16 life cycle, and stable cell lines were obtained that harbored the E7-deficient HPV-16 genome episomally, the state of the genome found in normal infections. By culturing these cells under conditions which promote the differentiation of epithelial cells, we found E7 to be necessary for the productive stage of the HPV-16 life cycle. HPV-16 lacking E7 failed to amplify its DNA and expressed reduced amounts of the capsid protein L1, which is required for virus production. E7 appears to create a favorable environment for HPV-16 DNA synthesis by perturbing the keratinocyte differentiation program and inducing the host DNA replication machinery. These data demonstrate that E7 plays an essential role in the papillomavirus life cycle.

scholarly journals Production of human papillomavirus type 16 virions in a keratinocyte cell line.

1990 ◽  
Vol 64 (12) ◽  
pp. 6305-6307 ◽  
Author(s):  
J Sterling ◽  
M Stanley ◽  
G Gatward ◽  
T Minson
Keyword(s):  
Human Papillomavirus ◽  
Cell Line ◽  
Human Papillomavirus Type 16 ◽  
Keratinocyte Cell

scholarly journals Differences in the Expression of Human Papillomavirus Type 16 (HPV-16) E6 Oncogene mRNA in SiHa Cell Line Inoculated with CMV, HSV or Ureaplasmas

2014 ◽  
Vol 62 (1) ◽  
pp. 70-75 ◽  
Author(s):  
Sława Szostek ◽  
Barbara Zawilińska ◽  
Małgorzata Biernat-Sudolska ◽  
Jolanta Kopeć ◽  
Ewa Kleszcz ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
Cell Line ◽  
Siha Cell ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Siha Cell Line

scholarly journals Multiple ASF/SF2 Sites in the Human Papillomavirus Type 16 (HPV-16) E4-Coding Region Promote Splicing to the Most Commonly Used 3′-Splice Site on the HPV-16 Genome

2010 ◽  
Vol 84 (16) ◽  
pp. 8219-8230 ◽  
Author(s):  
Monika Somberg ◽  
Stefan Schwartz
Keyword(s):  
Cervical Cancer ◽  
Human Papillomavirus ◽  
Splice Site ◽  
Binding Sites ◽  
Mrna Levels ◽  
Coding Region ◽  
Cervical Lesions ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
E6 And E7

ABSTRACT Our results presented here demonstrate that the most abundant human papillomavirus type 16 (HPV-16) mRNAs expressing the viral oncogenes E6 and E7 are regulated by cellular ASF/SF2, itself defined as a proto-oncogene and overexpressed in cervical cancer cells. We show that the most frequently used 3′-splice site on the HPV-16 genome, site SA3358, which is used to produce primarily E4, E6, and E7 mRNAs, is regulated by ASF/SF2. Splice site SA3358 is immediately followed by 15 potential binding sites for the splicing factor ASF/SF2. Recombinant ASF/SF2 binds to the cluster of ASF/SF2 sites. Mutational inactivation of all 15 sites abolished splicing to SA3358 and redirected splicing to the downstream-located, late 3′-splice site SA5639. Overexpression of a mutant ASF/SF2 protein that lacks the RS domain, also totally inhibited the usage of SA3358 and redirected splicing to the late 3′-splice site SA5639. The 15 ASF/SF2 binding sites could be replaced by an ASF/SF2-dependent, HIV-1-derived splicing enhancer named GAR. This enhancer was also inhibited by the mutant ASF/SF2 protein that lacks the RS domain. Finally, silencer RNA (siRNA)-mediated knockdown of ASF/SF2 caused a reduction in spliced HPV-16 mRNA levels. Taken together, our results demonstrate that the major HPV-16 3′-splice site SA3358 is dependent on ASF/SF2. SA3358 is used by the most abundantly expressed HPV-16 mRNAs, including those encoding E6 and E7. High levels of ASF/SF2 may therefore be a requirement for progression to cervical cancer. This is supported by our earlier findings that ASF/SF2 is overexpressed in high-grade cervical lesions and cervical cancer.

Cloning and sequencing of the murine farnesyltransferase α-encoding cDNA from a cell line which expresses the human papillomavirus type-16 E6 gene

Gene ◽  
1995 ◽  
Vol 164 (2) ◽  
pp. 373-374 ◽  
Author(s):  
Hiroshi Shirasawa ◽  
Tomoaki Kinoshita ◽  
Yuji Shino ◽  
Kohji Mori ◽  
Kumiko Shimizu ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
Cell Line ◽  
Cloning And Sequencing ◽  
Human Papillomavirus Type 16 ◽  
E6 Gene ◽  
A Cell

Detection of Class-Specific Antibodies to Baculovirus-Derived Human Papillomavirus Type 16 (HPV-16) Capsid Proteins

1994 ◽  
pp. 155-160 ◽  
Author(s):  
John Cason ◽  
Parminder K. Kambo ◽  
Bhavneet Shergill ◽  
John Bible ◽  
Barbara Kell ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
Capsid Proteins ◽  
Hpv 16 ◽  
Specific Antibodies ◽  
Human Papillomavirus Type 16

scholarly journals Human Papillomavirus Type 16 E7 Maintains Elevated Levels of the cdc25A Tyrosine Phosphatase during Deregulation of Cell Cycle Arrest

2002 ◽  
Vol 76 (2) ◽  
pp. 619-632 ◽  
Author(s):  
Don X. Nguyen ◽  
Thomas F. Westbrook ◽  
Dennis J. McCance
Keyword(s):  
Cell Cycle ◽  
Human Papillomavirus ◽  
Cell Cycle Arrest ◽  
Cell Cycle Progression ◽  
Tyrosine Phosphatase ◽  
Early Gene ◽  
Cycle Progression ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Cycle Arrest

ABSTRACT Essential to the oncogenic properties of human papillomavirus type 16 (HPV-16) are the activities encoded by the early gene product E7. HPV-16 E7 (E7.16) binds to cellular factors involved in cell cycle regulation and differentiation. These include the retinoblastoma tumor suppressor protein (Rb) and histone deacetylase (HDAC) complexes. While the biological significance of these interactions remains unclear, E7 is believed to help maintain cells in a proliferative state, thus establishing an environment that is conducive to viral replication. Most pathways that govern cell growth converge on downstream effectors. Among these is the cdc25A tyrosine phosphatase. cdc25A is required for G1/S transition, and its deregulation is associated with carcinogenesis. Considering the importance of cdc25A in cell cycle progression, it represents a relevant target for viral oncoproteins. Accordingly, the present study focuses on the putative deregulation of cdc25A by E7.16. Our results indicate that E7.16 can impede growth arrest induced during serum starvation and keratinocyte differentiation. Importantly, these E7-specific phenotypes correlate with elevated cdc25A steady-state levels. Reporter assays performed with NIH 3T3 cell lines and human keratinocytes indicate that E7 can transactivate the cdc25A promoter. In addition, transcriptional activation by E7.16 requires the distal E2F site within the cdc25A promoter. We further demonstrate that the ability of E7 to abrogate cell cycle arrest, activate cdc25A transcription, and increase cdc25A protein levels requires intact Rb and HDAC-1 binding domains. Finally, by using the cdk inhibitor roscovitine, we reveal that E7 activates the cdc25A promoter independently of cell cycle progression and cdk activity. Consequently, we propose that E7.16 can directly target cdc25A transcription and maintains cdc25A gene expression by disrupting Rb/E2F/HDAC-1 repressor complexes.

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