Variations in viral gene expression in friend virus-transformed cell lines congenic with respect to the H-2 locus

Respiratory syncytial virus (RSV) is a leading cause of pediatric acute respiratory infection worldwide. There are currently no approved vaccines or antivirals to combat RSV disease. A few transformed cell lines and two historic strains have been extensively used to study RSV. Here we report a thorough molecular and cell biological characterization of HEp-2 and A549 cells infected with four strains of RSV representing both major subgroups as well as historic and more contemporaneous genotypes -- [RSV/A/Tracy (GA1), RSV/A/Ontario (ON), RSV/B/18537 (GB1), RSV/B/Buenos Aires (BA)] -- via measurements of viral replication kinetics and viral gene expression, immunofluorescence-based imaging of gross cellular morphology and cell-associated RSV, and measurements of host response including transcriptional changes and levels of secreted cytokines and growth factors. Our findings strongly suggest 1) the existence of a conserved difference in gene expression between RSV subgroups A and B; 2) the A549 cell line is a more stringent and natural host of replicating RSV than the HEp-2 cell line; and 3) consistent with previous studies, determining the full effects of viral genetic variation in RSV pathogenesis requires model systems as tractable as transformed cell lines but better representative of the human host.

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Human Cytomegalovirus Protein pp71 Displaces the Chromatin-Associated Factor ATRX from Nuclear Domain 10 at Early Stages of Infection

Journal of Virology ◽

10.1128/jvi.01215-08 ◽

2008 ◽

Vol 82 (24) ◽

pp. 12543-12554 ◽

Cited By ~ 87

Author(s):

Vera Lukashchuk ◽

Steven McFarlane ◽

Roger D. Everett ◽

Chris M. Preston

Keyword(s):

Gene Expression ◽

Cell Lines ◽

Human Cytomegalovirus ◽

Viral Gene Expression ◽

Cellular Protein ◽

Viral Gene ◽

Nuclear Domain ◽

Simplex Virus ◽

Transformed Cell Lines

ABSTRACT The human cytomegalovirus (HCMV) tegument protein pp71, encoded by gene UL82, stimulates viral immediate-early (IE) transcription. pp71 interacts with the cellular protein hDaxx at nuclear domain 10 (ND10) sites, resulting in the reversal of hDaxx-mediated repression of viral transcription. We demonstrate that pp71 displaces an hDaxx-binding protein, ATRX, from ND10 prior to any detectable effects on hDaxx itself and that this event contributes to the role of pp71 in alleviating repression. Introduction of pp71 into cells by transfection, infection with a pp71-expressing herpes simplex virus type 1 vector, or by generation of transformed cell lines promoted the rapid relocation of ATRX from ND10 to the nucleoplasm without alteration of hDaxx levels or localization. A pp71 mutant protein unable to interact with hDaxx did not affect the intranuclear distribution of ATRX. Infection with HCMV at a high multiplicity of infection resulted in rapid displacement of ATRX from ND10, the effect being observed maximally by 2 h after adsorption, whereas infection with the UL82-null HCMV mutant ADsubUL82 did not affect ATRX localization even at 7 h postinfection. Cell lines depleted of ATRX by transduction with shRNA-expressing lentiviruses supported increased IE gene expression and virus replication after infection with ADsubUL82, demonstrating that ATRX has a role in repressing IE transcription. The results show that ATRX, in addition to hDaxx, is a component of cellular intrinsic defenses that limit HCMV IE transcription and that displacement of ATRX from ND10 by pp71 is important for the efficient initiation of viral gene expression.

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Differential early viral gene expression in two stages of human papillomavirus type 16 DNA-induced malignant transformation.

Molecular and Cellular Biology ◽

10.1128/mcb.7.6.2165 ◽

1987 ◽

Vol 7 (6) ◽

pp. 2165-2172 ◽

Cited By ~ 14

Author(s):

S Yasumoto ◽

J Doniger ◽

J A DiPaolo

Keyword(s):

Gene Expression ◽

Human Papillomavirus ◽

Malignant Transformation ◽

Cell Lines ◽

Viral Gene Expression ◽

Viral Gene ◽

3T3 Cells ◽

Hpv 16 ◽

Nih 3T3 ◽

Nih 3T3 Cells

Human papillomavirus (HPV) type 16 DNA induces progressive transformation in NIH 3T3 cells. Two types of cell lines, PM3T3G0 and PM3T3Fo, were isolated by G418 or focus selection, respectively, after transfection of cells by a recombinant HPV 16 DNA carrying the neo gene. These cell lines exhibited distinct phenotypes compared with controls. Saturation densities of PM3T3G0 and PM3T3Fo lines were two- to three- and five- to sevenfold greater than that of control NIH 3T3 cells, respectively. Neither cell type required high serum for growth, in contrast to NIH 3T3 cells. PM3T3G0 lines were premalignant, whereas PM3T3Fo lines manifested tumorigenicity within 2 weeks. Subpopulations of three PM3T3G0 lines underwent progressive transformation as reflected by focus formation. Analysis of HPV 16-specific mRNA species demonstrated that high levels of early and late gene expression were detected in premalignant PM3T3G0 lines, whereas relatively low quantities of selected gene messages were expressed in malignant transformants. Thus, high levels of viral gene expression are not crucial for malignant transformation.

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Targeted Editing of the pp38 Gene in Marek’s Disease Virus-Transformed Cell Lines Using CRISPR/Cas9 System

Viruses ◽

10.3390/v11050391 ◽

2019 ◽

Vol 11 (5) ◽

pp. 391 ◽

Cited By ~ 7

Author(s):

Yaoyao Zhang ◽

Jun Luo ◽

Na Tang ◽

Man Teng ◽

Vishwanatha R.A.P. Reddy ◽

...

Keyword(s):

Disease Virus ◽

Cell Lines ◽

Marek's Disease Virus ◽

Marek's Disease ◽

Viral Gene ◽

Marek’S Disease Virus ◽

Marek’S Disease ◽

Transformed Cell ◽

Transformed Cell Lines

Marek’s disease virus (MDV), a lymphotropic α-herpesvirus associated with T-cell lymphomas in chickens, is an excellent model for herpesvirus biology and virus-induced oncogenesis. Marek’s disease (MD) is also one of the cancers against which a vaccine was first used. In the lymphomas and lymphoblastoid cell lines (LCLs) derived from them, MDV establishes latent infection with limited gene expression. Although LCLs are valuable for interrogating viral and host gene functions, molecular determinants associated with the maintenance of MDV latency and lytic switch remain largely unknown, mainly due to the lack of tools for in situ manipulation of the genomes in these cell lines. Here we describe the first application of CRISPR/Cas9 editing approach for precise editing of the viral gene phosphoprotein 38 (pp38), a biomarker for latent/lytic switch in MDV-transformed LCLs MDCC-MSB-1 (Marek’s disease cell line MSB-1) and MDCC-HP8. Contradictory to the previous reports suggesting that pp38 is involved in the maintenance of transformation of LCL MSB-1 cells, we show that pp38-deleted cells proliferated at a significant higher rate, suggesting that pp38 is dispensable for the transformed state of these cell lines. Application of CRISPR/Cas9-based gene editing of MDV-transformed cell lines in situ opens up further opportunities towards a better understanding of MDV pathogenesis and virus-host interactions.

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Iodide symporter gene expression in normal and transformed rat thyroid cells

Acta Endocrinologica ◽

10.1530/eje.0.1400447 ◽

1999 ◽

pp. 447-451 ◽

Cited By ~ 42

Author(s):

F Trapasso ◽

R Iuliano ◽

E Chiefari ◽

F Arturi ◽

A Stella ◽

...

Keyword(s):

Gene Expression ◽

Cell Lines ◽

Inhibitory Effect ◽

Mrna Levels ◽

Iodide Uptake ◽

Thyroid Cells ◽

Transformed Cell ◽

Nis Gene ◽

Rat Thyroid ◽

Transformed Cell Lines

OBJECTIVE: Decrease or loss of the Na+/I- symporter (NIS) activity profoundly affects the suitability of the use of radioiodine to detect or treat metastatic thyroid tissues. The aim of our study was to verify whether specific oncogene abnormalities were responsible for the alteration in NIS activity in thyroid cells. DESIGN AND METHODS: Expression of the NIS gene was investigated by Northern blot analysis in normal and in some oncogene-transformed cell lines with different degrees of malignancy which had lost the iodide uptake ability. RESULTS: NIS gene expression was up-regulated by TSH in a dose-dependent and time-dependent way in normal PC Cl 3 cells. The same effect was observed by activating the cAMP-dependent pathway by forskolin. Conversely, insulin and 12-O-tetradecanoylphorbol-13-acetate (TPA) showed a partial inhibitory effect on NIS gene expression. The oncogene-transformed cell lines PC v-erbA, PC HaMSV, PC v-raf, and PC E1A cells showed reduced NIS mRNA levels compared with the normal PC Cl 3 cells. Conversely, an almost complete absence of NIS gene expression was found in PC RET/PTC, PC KiMSV, PC p53(143ala), and PC PyMLV cell lines. CONCLUSIONS: Our data show that oncogene activation could play a role in affecting the iodide uptake ability in thyroid tumoral cells; different mechanisms are involved in the oncogene-dependent loss of NIS activity in transformed thyroid cells.

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Ornithine decarboxylase gene expression is aberrantly regulated via the cAMP signal transduction pathway in malignant H-ras transformed cell lines

Journal of Cellular Physiology ◽

10.1002/jcp.1041610224 ◽

1994 ◽

Vol 161 (2) ◽

pp. 383-391 ◽

Cited By ~ 7

Author(s):

Robert A. R. Hurta ◽

Jim A. Wright

Keyword(s):

Gene Expression ◽

Signal Transduction ◽

Cell Lines ◽

Ornithine Decarboxylase ◽

Signal Transduction Pathway ◽

Transduction Pathway ◽

Transformed Cell ◽

Transformed Cell Lines

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Progressive Shutdown of Viral Gene Expression in Friend-virus-induced Erythroleukemia Cells

Cold Spring Harbor Symposia on Quantitative Biology ◽

10.1101/sqb.1980.044.01.095 ◽

1980 ◽

Vol 44 (0) ◽

pp. 887-892

Author(s):

A. S. Berkower ◽

F. Plata ◽

R. Anand ◽

F. Lilly ◽

R. Soeiro ◽

...

Keyword(s):

Gene Expression ◽

Viral Gene Expression ◽

Viral Gene ◽

Friend Virus ◽

Erythroleukemia Cells

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NAD-linked mechanisms of gene de-repression and a novel role for CtBP in persistent adenovirus infection of lymphocytes

Virology Journal ◽

10.1186/s12985-019-1265-y ◽

2019 ◽

Vol 16 (1) ◽

Cited By ~ 1

Author(s):

Megan L. Dickherber ◽

Charlie Garnett-Benson

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Cell Lines ◽

Lymphocyte Activation ◽

Viral Gene Expression ◽

Productive Infection ◽

Viral Gene ◽

Global Changes ◽

Persistently Infected ◽

Infected Cells

Abstract Background Adenovirus (AdV) infection is ubiquitous in the human population and causes acute infection in the respiratory and gastrointestinal tracts. In addition to lytic infections in epithelial cells, AdV can persist in a latent form in mucosal lymphocytes, and nearly 80% of children contain viral DNA in the lymphocytes of their tonsils and adenoids. Reactivation of latent AdV is thought to be the source of deadly viremia in pediatric transplant patients. Adenovirus latency and reactivation in lymphocytes is not well studied, though immune cell activation has been reported to promote productive infection from latency. Lymphocyte activation induces global changes in cellular gene expression along with robust changes in metabolic state. The ratio of free cytosolic NAD+/NADH can impact gene expression via modulation of transcriptional repressor complexes. The NAD-dependent transcriptional co-repressor C-terminal Binding Protein (CtBP) was discovered 25 years ago due to its high affinity binding to AdV E1A proteins, however, the role of this interaction in the viral life cycle remains unclear. Methods The dynamics of persistently- and lytically-infected cells are evaluated. RT-qPCR is used to evaluate AdV gene expression following lymphocyte activation, treatment with nicotinamide, or disruption of CtBP-E1A binding. Results PMA and ionomycin stimulation shifts the NAD+/NADH ratio in lymphocytic cell lines and upregulates viral gene expression. Direct modulation of NAD+/NADH by nicotinamide treatment also upregulates early and late viral transcripts in persistently-infected cells. We found differential expression of the NAD-dependent CtBP protein homologs between lymphocytes and epithelial cells, and inhibition of CtBP complexes upregulates AdV E1A expression in T lymphocyte cell lines but not in lytically-infected epithelial cells. Conclusions Our data provide novel insight into factors that can regulate AdV infections in activated human lymphocytes and reveal that modulation of cellular NAD+/NADH can de-repress adenovirus gene expression in persistently-infected lymphocytes. In contrast, disrupting the NAD-dependent CtBP repressor complex interaction with PxDLS-containing binding partners paradoxically alters AdV gene expression. Our findings also indicate that CtBP activities on viral gene expression may be distinct from those occurring upon metabolic alterations in cellular NAD+/NADH ratios or those occurring after lymphocyte activation.

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Epstein-Barr Virus (EBV) in Endemic Burkitt's Lymphoma: Molecular Analysis of Primary Tumor Tissue

Blood ◽

10.1182/blood.v91.4.1373 ◽

1998 ◽

Vol 91 (4) ◽

pp. 1373-1381 ◽

Cited By ~ 124

Author(s):

Qian Tao ◽

Keith D. Robertson ◽

Angela Manns ◽

Allan Hildesheim ◽

Richard F. Ambinder

Keyword(s):

Gene Expression ◽

Cell Lines ◽

Epstein Barr Virus ◽

Viral Gene Expression ◽

Burkitt’S Lymphoma ◽

Burkitt's Lymphoma ◽

Viral Gene ◽

Viral Strain ◽

Barr Virus ◽

Epstein Barr

Abstract Many aspects of Epstein-Barr virus (EBV) and tumor biology have been studied in Burkitt's lymphoma (BL)-derived cell lines. However, in tissue culture, patterns of gene expression and C promoter-G (CpG) methylation often change and viral strain selection may occur. In this report, 10 cases of snap-frozen endemic BL tumors are characterized in terms of viral gene expression, promoter usage, methylation, and viral strain. EBNA1 and BamHI-A rightward transcripts (BART) were detected in 7 of 7 and LMP2A transcripts in 5 of 7 tumors with well-preserved RNA. Transcripts for the other EBNAs and for LMP1 were not detected in any tumor. These tumors differ from BL cell lines in that they lack a variety of lytic cycle transcripts. This pattern of viral gene expression in endemic BL is similar to that reported in peripheral blood mononuclear cells (PBMCs) from healthy EBV–seropositive individuals. EBNA1 transcripts originated from the Q promoter (Qp) but not C, W, or F promoters that drive transcription of EBNA1 in other circumstances. Whereas Cp has been previously shown to be entirely CpG methylated in BL, bisulfite genomic sequencing showed virtually no methylation in Qp. Type-A EBV was detected in 6 of 10 and type B in 4 of 10 cases. A previously reported 30bp deletion variant in the carboxyl terminal of LMP1 gene was detected in 5 of 10 cases. The association with both A and B strains contrasts with EBV–associated Hodgkin's disease, nasopharyngeal carcinoma, and post-transplant lymphoproliferative disease, which are much more consistently associated with A strain virus.

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