Human cytomegalovirus infection inhibits cell cycle progression at multiple points, including the transition from G1 to S.

ABSTRACT Earlier studies have revealed that human cytomegalovirus rapidly inhibits the growth of fibroblasts, blocking cell cycle progression at multiple points, including the G1-to-S-phase transition. The present study demonstrates that the UL69 protein, a virus-encoded constituent of the virion, is able to arrest cell cycle progression when introduced into uninfected cells. Expression of the UL69 protein causes U2 OS cells and primary human fibroblasts to accumulate within the G1 compartment of the cell cycle, and serum fails to induce the progression of quiescent human fibroblasts into the S phase when the protein is present. Therefore, the UL69 protein is at least partially responsible for the cell cycle block that is instituted after infection of permissive cells with human cytomegalovirus.

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Inhibition of Cellular DNA Synthesis by the Human Cytomegalovirus IE86 Protein Is Necessary for Efficient Virus Replication

Journal of Virology ◽

10.1128/jvi.80.8.3872-3883.2006 ◽

2006 ◽

Vol 80 (8) ◽

pp. 3872-3883 ◽

Cited By ~ 43

Author(s):

Dustin T. Petrik ◽

Kimberly P. Schmitt ◽

Mark F. Stinski

Keyword(s):

Cell Cycle ◽

Dna Synthesis ◽

Human Cytomegalovirus ◽

Cell Cycle Progression ◽

Cell Cycle Control ◽

Single Amino Acid ◽

Cycle Progression ◽

Artificial Chromosomes ◽

Early Genes ◽

Cellular Dna

ABSTRACT Human cytomegalovirus (HCMV) expresses several proteins that manipulate normal cellular functions, including cellular transcription, apoptosis, immune response, and cell cycle control. The IE2 gene, which is expressed from the HCMV major immediate-early (MIE) promoter, encodes the IE86 protein. IE86 is a multifunctional protein that is essential for viral replication. The functions of IE86 include transactivation of cellular and viral early genes, negative autoregulation of the MIE promoter, induction of cell cycle progression from G0/G1 to G1/S, and arresting cell cycle progression at the G1/S transition in p53-positive human foreskin fibroblast (HFF) cells. Mutations were introduced into the IE2 gene in the context of the viral genome using bacterial artificial chromosomes (BACs). From these HCMV BACs, a recombinant virus (RV) with a single amino acid substitution in the IE86 protein was isolated that replicates slower and to lower titers than wild-type HCMV. HFF cells infected with the Q548R RV undergo cellular DNA synthesis and do not arrest at any point in the cell cycle. The Q548R RV is able to negatively autoregulate the MIE promoter, transactivate viral early genes, activate cellular E2F-responsive genes, and produce infectious virus. This is the first report of a viable recombinant HCMV that is unable to inhibit cellular DNA synthesis in infected HFF cells.

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Toll-like receptor 4 is involved in the cell cycle modulation and required for effective human cytomegalovirus infection in THP-1 macrophages

Virology ◽

10.1016/j.virol.2013.01.021 ◽

2013 ◽

Vol 440 (1) ◽

pp. 19-30 ◽

Cited By ~ 5

Author(s):

Maria-Cristina Arcangeletti ◽

Diego Germini ◽

Isabella Rodighiero ◽

Prisco Mirandola ◽

Flora De Conto ◽

...

Keyword(s):

Cell Cycle ◽

Human Cytomegalovirus ◽

Cytomegalovirus Infection ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Cell Cycle Modulation ◽

Human Cytomegalovirus Infection

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Human cytomegalovirus mediates cell cycle progression through G1 into early S phase in terminally differentiated cells

Journal of General Virology ◽

10.1099/0022-1317-81-6-1553 ◽

2000 ◽

Vol 81 (6) ◽

pp. 1553-1565 ◽

Cited By ~ 36

Author(s):

John Sinclair ◽

Joan Baillie ◽

Richard Caswell ◽

Linda Bryant

Keyword(s):

Cell Cycle ◽

Human Cytomegalovirus ◽

Cell Cycle Progression ◽

S Phase ◽

Cycle Progression ◽

Differentiated Cells

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The aryl hydrocarbon receptor facilitates the human cytomegalovirus-mediated G1/S block to cell cycle progression

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2026336118 ◽

2021 ◽

Vol 118 (12) ◽

pp. e2026336118

Author(s):

Pooya Naseri-Nosar ◽

Maciej T. Nogalski ◽

Thomas Shenk

Keyword(s):

Cell Cycle ◽

Aryl Hydrocarbon Receptor ◽

Human Cytomegalovirus ◽

Cell Cycle Progression ◽

Hcmv Infection ◽

Cell Interaction ◽

Cycle Progression ◽

Aryl Hydrocarbon ◽

Cell Transcriptome ◽

Cell Cycle Block

The tryptophan metabolite, kynurenine, is known to be produced at elevated levels within human cytomegalovirus (HCMV)-infected fibroblasts. Kynurenine is an endogenous aryl hydrocarbon receptor (AhR) ligand. Here we show that the AhR is activated following HCMV infection, and pharmacological inhibition of AhR or knockdown of AhR RNA reduced the accumulation of viral RNAs and infectious progeny. RNA-seq analysis of infected cells following AhR knockdown showed that the receptor alters the levels of numerous RNAs, including RNAs related to cell cycle progression. AhR knockdown alleviated the G1/S cell cycle block that is normally instituted in HCMV-infected fibroblasts, consistent with its known ability to regulate cell cycle progression and cell proliferation. In sum, AhR is activated by kynurenine and perhaps other ligands produced during HCMV infection, it profoundly alters the infected-cell transcriptome, and one outcome of its activity is a block to cell cycle progression, providing mechanistic insight to a long-known element of the virus–host cell interaction.

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The Human Cytomegalovirus IE86 Protein Can Block Cell Cycle Progression after Inducing Transition into the S Phase of Permissive Cells

Journal of Virology ◽

10.1128/jvi.74.15.7108-7118.2000 ◽

2000 ◽

Vol 74 (15) ◽

pp. 7108-7118 ◽

Cited By ~ 103

Author(s):

Eain A. Murphy ◽

Daniel N. Streblow ◽

Jay A. Nelson ◽

Mark F. Stinski

Keyword(s):

Cell Cycle ◽

Protein Expression ◽

Human Cytomegalovirus ◽

Cell Cycle Progression ◽

Hcmv Infection ◽

Fluorescent Protein ◽

Cell Types ◽

S Phase ◽

Cycle Progression ◽

Green Fluorescent

ABSTRACT Human cytomegalovirus (HCMV) infection of permissive cells has been reported to induce a cell cycle halt. One or more viral proteins may be involved in halting progression at different stages of the cell cycle. We investigated how HCMV infection, and specifically IE86 protein expression, affects the cell cycles of permissive and nonpermissive cells. We used a recombinant virus that expresses the green fluorescent protein (GFP) to determine the effects of HCMV on the cell cycle of permissive cells. Fluorescence by GFP allowed us to select for only productively infected cells. Replication-defective adenovirus vectors expressing the IE72 or IE86 protein were also used to efficiently transduce 95% or more of the cells. The adenovirus-expressed IE86 protein was determined to be functional by demonstrating negative autoregulation of the major immediate-early promoter and activation of an early viral promoter in the context of the viral genome. To eliminate adenovirus protein effects, plasmids expressing GFP for fluorescent selection of only transfected cells and wild-type IE86 protein or a mutant IE86 protein were tested in permissive and nonpermissive cells. HCMV infection induced the entry of U373 cells into the S phase. All permissive cells infected with HCMV were blocked in cell cycle progression and could not divide. After either transduction or transfection and IE86 protein expression, the number of all permissive or nonpermissive cell types in the S phase increased significantly, but the cells could no longer divide. The IE72 protein did not have a significant effect on the S phase. Since IE86 protein inhibits cell cycle progression, the IE2 gene in a human fibroblast IE86 protein-expressing cell line was sequenced. The IE86 protein in these retrovirus-transduced cells has mutations in a critical region of the viral protein. The locations of the mutations and the function of the IE86 protein in controlling cell cycle progression are discussed.

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Effects of Human Cytomegalovirus Major Immediate-Early Proteins in Controlling the Cell Cycle and Inhibiting Apoptosis: Studies with ts13 Cells

Journal of Virology ◽

10.1128/jvi.73.4.2825-2831.1999 ◽

1999 ◽

Vol 73 (4) ◽

pp. 2825-2831 ◽

Cited By ~ 38

Author(s):

David M. Lukac ◽

James C. Alwine

Keyword(s):

Cell Cycle ◽

Human Cytomegalovirus ◽

Cell Cycle Progression ◽

Cellular Transformation ◽

Immediate Early ◽

Temperature Sensitive ◽

Cycle Progression ◽

Early Proteins ◽

Immediate Early Proteins ◽

Cell Cycle Block

ABSTRACT The major immediate-early (MIE) gene of human cytomegalovirus (HCMV) encodes several MIE proteins (MIEPs) produced as a result of alternative splicing and polyadenylation of the primary transcript. Previously we demonstrated that the HCMV MIEPs expressed from the entire MIE gene could rescue the temperature-sensitive (ts) transcriptional defect in the ts13 cell line. This defect is caused by a ts mutation in TAFII250, the 250-kDa TATA binding protein-associated factor (TAF). These and other data suggested that the MIEPs perform a TAF-like function in complex with the basal transcription factor TFIID. In addition to the transcriptional defect, the ts mutation in ts13 cells results in a defect in cell cycle progression which ultimately leads to apoptosis. Since all of these defects can be rescued by wild-type TAFII250, we asked whether the MIEPs could rescue the cell cycle defect and/or affect the progression to apoptosis. We have found that the MIEPs, expressed from the entire MIE gene, do not rescue the cell cycle block in ts13 cells grown at the nonpermissive temperature. However, despite the maintenance of the cell cycle block, the ts13 cells which express the MIEPs are resistant to apoptosis. MIEP mutants, which have previously been shown to be defective in rescuing the ts transcriptional defect, maintained the ability to inhibit apoptosis. Hence, the MIEP functions which affect transcription appear to be separable from the functions which inhibit apoptosis. We discuss these data in the light of the HCMV life cycle and the possibility that the MIEPs promote cellular transformation by a “hit-and-run” mechanism.

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