Coronavirus PEDV nucleocapsid protein interacts with p53 to induce cell cycle arrest in S-phase and promotes viral replication

Subversion of the host cell cycle to facilitate viral replication is a common feature of coronavirus infections. Coronavirus nucleocapsid (N) protein could modulate host cell cycle, but the mechanistic details remain largely unknown. Here, we investigated manipulation of porcine epidemic diarrhea virus (PEDV) N protein on cell cycle and its influence on viral replication. Results indicated that PEDV N-induced Vero E6 cell cycle arrest at S-phase, which promoted viral replication ( P < 0.05). S-phase arrest was dependent on N protein nuclear localization signal S 71 NWHFYYLGTGPHADLRYRT 90 and interaction between N protein and p53. In the nucleus, the binding of N protein to p53 maintained consistently high-level expression of p53, which activated p53-DREAM pathway. The key domain of the N protein interacting with p53 was revealed to be S 171 RGNSQNRGNNQGRGASQNRGGNN 194 (N S171-N194 ), in which G 183 RG 185 are core sites. N S171-N194 and G 183 RG 185 were essential for N-induced S-phase arrest. Moreover, small molecular drugs targeting the N S171-N194 domain of PEDV N protein were screened through molecular docking. Hyperoside could antagonize N protein-induced S-phase arrest by interfering with interaction between N protein and p53 and inhibit viral replication ( P < 0.05). The above experiments were also validated in porcine intestinal cells, and resulting data were in line with that of Vero E6 cells. Therefore, these results revealed that PEDV N protein interacted with p53 to activate p53-DREAM pathway, and subsequently induced S-phase arrest to create a favorable environment for virus replication. These findings provided new insight into the PEDV-host interaction and the design of novel antiviral strategies against PEDV.

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Impaired S Phase Arrest in AML Cells with a FLT3-ITD Treated with Clofarabine Allows Prolonged Drug exposure to Reverse the Chemoresistant Phenotype.

Blood ◽

10.1182/blood.v114.22.1000.1000 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1000-1000

Author(s):

Claire Seedhouse ◽

Martin Grundy ◽

Shili Shang ◽

John Ronan ◽

Heather Pimblett ◽

...

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Dna Repair ◽

Cell Cycle Arrest ◽

Short Pulse ◽

S Phase ◽

Mrna Levels ◽

Cycle Arrest ◽

Phase Arrest ◽

S Phase Arrest

Abstract Abstract 1000 Poster Board I-22 We have previously reported that AML cells with a FLT3-ITD have enhanced DNA repair mechanisms following exposure to DNA-damaging drugs which may be a mechanism of chemoresistance. Clofarabine is a novel nucleoside analogue, active in S-phase, with efficacy in AML and is incorporated into DNA as clofarabine triphosphate. Here we show that in FLT3-ITD cells enhanced repair, and therefore resistance to clofarabine-induced DNA damage and toxicity, can be reversed by prolonged drug incubation. When treated with clofarabine, FLT3-ITD-harbouring MOLM13 and MV4.11 cells undergo similar levels of DNA damage (γH2A.X foci) to FLT3 wildtype (WT) cells (HL60 and KG1). After a short pulse of drug the FLT3-ITD cells have a superior repair capability than WT cells; following a 2 hour washout period γH2A.X positivity found immediately after treatment had almost completely disappeared in the FLT3-ITD cells (<10% γH2A.X remaining), whereas in the FLT3-WT cells significant damage (γH2A.X) remained (>40%). Furthermore, after a 1 hour pulse of clofarabine, whereas the FLT3-WT cells under go rapid S phase arrest the S-phase checkpoint fails in the FLT3-ITD cells: reduction in the proportion of cells synthesising DNA is >80% in FLT3-WT cells and <10% in FLT3-ITD cells. Cell cycle arrest in response to DNA damage in S phase is affected via loss of the transcriptional regulator cdc25A. This loss of expression of cdc25A fails to take place in clofarabine-treated FLT3 mutant cells compared to WT cells. In addition, cdc25A mRNA levels are maintained by the FLT3-ITD as demonstrated by siRNA to FLT3 which reduced cdc25A mRNA levels in MV4.11 cells by 87.5%. Primary FLT3 mutant samples from AML patients(n=3) also display impaired cell cycle arrest upon treatment with clofarabine and show enhanced sensitivity on prolonged treatment (24 hours) compared to wildtype samples (n=2). We conclude that there is a reversal of phenotype in mutant FLT3 cells dependant on the length of exposure to clofarabine. Efficient DNA repair renders the cells resistant to a short pulse of the drug, but a failure of cell cycle checkpoint(s) in S phase, mediated by cdc25A, renders the cells sensitive to prolonged exposure. These results may have implications for the scheduling of clofarabine in clinical studies. Disclosures: No relevant conflicts of interest to declare.

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Rhein Induces Apoptosis and Cell Cycle Arrest in Human Hepatocellular Carcinoma BEL-7402 Cells

The American Journal of Chinese Medicine ◽

10.1142/s0192415x08006259 ◽

2008 ◽

Vol 36 (04) ◽

pp. 805-813 ◽

Cited By ~ 47

Author(s):

Ping Shi ◽

Zhiwei Huang ◽

Guichen Chen

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Chromatin Condensation ◽

Critical Role ◽

S Phase ◽

Dependent Manner ◽

Hepatocelluar Carcinoma ◽

Cycle Arrest ◽

Phase Arrest ◽

S Phase Arrest

Rhein, an anthraquinone derivative of rhubarb, inhibits the proliferation of various human cancer cells. In this paper, we focused on studying the effects of rhein on human hepatocelluar carcinoma BEL-7402 cells and further understanding the underlying molecular mechanism in an effort to make the potential development of rhein in the treatment of cancers. Using MTT assay and flow cytometry, we demonstrate a critical role of rhein in the suppression of BEL-7402 cell proliferation in a concentration- and time-dependent manner. The increase of apoptosis rate was observed after incubation of BEL-7402 cells with rhein at 50–200 μM for 48 hours, and the cells exhibit typical apoptotic features including cellular morphological change and chromatin condensation. Moreover, rhein-induced cell cycle S-phase arrest. Additionally, after rhein treatment, expression levels of c-Myc gene were decreased, while those of caspase-3 gene were increased in a dose-dependent manner by using real-time PCR assay. The results demonstrate for the first time that cell cycle S-phase arrest is one of the mechanisms of rhein in inhibition of BEL-7402 cells. Rhein plays its role by inducing cell cycle arrest via downregulation of oncogene c-Myc and apoptosis through the caspase-dependent pathway. It is expected that rhein will be effective and useful as a new agent in hepatocelluar carcinoma treatment in the future.

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Legionella pneumophila translocated translation inhibitors are required for bacterial-induced host cell cycle arrest

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1820093116 ◽

2019 ◽

Vol 116 (8) ◽

pp. 3221-3228 ◽

Cited By ~ 6

Author(s):

Asaf Sol ◽

Erion Lipo ◽

Dennise A. de Jesús-Díaz ◽

Connor Murphy ◽

Mildred Devereux ◽

...

Keyword(s):

Cell Cycle ◽

Cyclin D1 ◽

Cell Cycle Arrest ◽

Host Cell ◽

Legionella Pneumophila ◽

S Phase ◽

Phase Cell ◽

Cycle Arrest ◽

Bacterial Replication ◽

Cell Cycle Machinery

The cell cycle machinery controls diverse cellular pathways and is tightly regulated. Misregulation of cell division plays a central role in the pathogenesis of many disease processes. Various microbial pathogens interfere with the cell cycle machinery to promote host cell colonization. Although cell cycle modulation is a common theme among pathogens, the role this interference plays in promoting diseases is unclear. Previously, we demonstrated that the G1 and G2/M phases of the host cell cycle are permissive for Legionella pneumophila replication, whereas S phase provides a toxic environment for bacterial replication. In this study, we show that L. pneumophila avoids host S phase by blocking host DNA synthesis and preventing cell cycle progression into S phase. Cell cycle arrest upon Legionella contact is dependent on the Icm/Dot secretion system. In particular, we found that cell cycle arrest is dependent on the intact enzymatic activity of translocated substrates that inhibits host translation. Moreover, we show that, early in infection, the presence of these translation inhibitors is crucial to induce the degradation of the master regulator cyclin D1. Our results demonstrate that the bacterial effectors that inhibit translation are associated with preventing entry of host cells into a phase associated with restriction of L. pneumophila. Furthermore, control of cyclin D1 may be a common strategy used by intracellular pathogens to manipulate the host cell cycle and promote bacterial replication.

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The Severe Fever with Thrombocytopenia Syndrome Virus NSs Protein Interacts with CDK1 To Induce G2 Cell Cycle Arrest and Positively Regulate Viral Replication

Journal of Virology ◽

10.1128/jvi.01575-19 ◽

2019 ◽

Vol 94 (6) ◽

Cited By ~ 3

Author(s):

Sihua Liu ◽

Hongyun Liu ◽

Jun Kang ◽

Leling Xu ◽

Keke Zhang ◽

...

Keyword(s):

Cell Cycle ◽

Viral Replication ◽

Cell Cycle Arrest ◽

Host Cell ◽

Nuclear Import ◽

Hemorrhagic Fever ◽

Cyclin B1 ◽

Cycle Arrest ◽

Infected Cells ◽

Severe Fever

ABSTRACT Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly identified phlebovirus associated with severe hemorrhagic fever in humans. While many viruses subvert the host cell cycle to promote viral growth, it is unknown whether this is a strategy employed by SFTSV. In this study, we investigated how SFTSV manipulates the cell cycle and the effect of the host cell cycle on SFTSV replication. Our results suggest that cells arrest at the G2/M transition following infection with SFTSV. The accumulation of cells at the G2/M transition did not affect virus adsorption and entry but did facilitate viral replication. In addition, we found that SFTSV NSs, a nonstructural protein that forms viroplasm-like structures in the cytoplasm of infected cells and promotes virulence by modulating the interferon response, induces a large number of cells to arrest at the G2/M transition by interacting with CDK1. The interaction between NSs and CDK1, which is inclusion body dependent, inhibits formation and nuclear import of the cyclin B1-CDK1 complex, thereby leading to cell cycle arrest. Expression of a CDK1 loss-of-function mutant reversed the inhibitive effect of NSs on the cell cycle, suggesting that this protein is a potential antiviral target. Our study provides new insight into the role of a specific viral protein in SFTSV replication, indicating that NSs induces G2/M arrest of SFTSV-infected cells, which promotes viral replication. IMPORTANCE Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tick-borne pathogen that causes severe hemorrhagic fever. Although SFTSV poses a serious threat to public health and was recently isolated, its pathogenesis remains unclear. In particular, the relationship between SFTSV infection and the host cell cycle has not been described. Here, we show for the first time that both asynchronized and synchronized SFTSV-susceptible cells arrest at the G2/M checkpoint following SFTSV infection and that the accumulation of cells at this checkpoint facilitates viral replication. We also identify a key mechanism underlying SFTSV-induced G2/M arrest, in which SFTSV NSs interacts with CDK1 to inhibit formation and nuclear import of the cyclin B1-CDK1 complex, thus preventing it from regulating cell cycle progression. Our study highlights the key role that NSs plays in SFTSV-induced G2/M arrest.

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Duck Plague Virus Promotes DEF Cell Apoptosis by Activating Caspases, Increasing Intracellular ROS Levels and Inducing Cell Cycle S-Phase Arrest

Viruses ◽

10.3390/v11020196 ◽

2019 ◽

Vol 11 (2) ◽

pp. 196 ◽

Cited By ~ 3

Author(s):

Chuankuo Zhao ◽

Mingshu Wang ◽

Anchun Cheng ◽

Qiao Yang ◽

Ying Wu ◽

...

Keyword(s):

Cell Cycle ◽

Viral Replication ◽

Cell Cycle Progression ◽

S Phase ◽

Mrna Levels ◽

Phase Arrest ◽

Duck Plague Virus ◽

Intracellular Ros ◽

S Phase Arrest ◽

Induced Apoptosis

Background: Duck plague virus (DPV) can induce apoptosis in duck embryo fibroblasts (DEFs) and in infected ducks, but the molecular mechanism of DPV-induced apoptosis remains unknown. Methods: We first used qRT-PCR and a Caspase-Glo assay to determine whether the caspase protein family plays an important role in DPV-induced apoptosis. Then, we used an intracellular ROS detection kit and the mitochondrial probe JC-1 to respectively detect ROS levels and mitochondrial membrane potential (MMP). Finally, flow cytometry was used to detect apoptosis and cell cycle progression. Results: In this study, the mRNA levels and enzymatic activities of caspase-3, caspase-7, caspase-8, and caspase-9 were significantly increased during DPV-induced apoptosis. The caspase inhibitors Z-DEVD-FMK, Z-LEHD-FMK, and Q-VD-OphA could inhibit DPV-induced apoptosis and promote viral replication. Subsequently, a significant decrease in MMP and an increase in the intracellular ROS levels were observed. Further study showed that pretreating infected cells with NAC (a ROS scavenger) decreased the intracellular ROS levels, increased the MMP, inhibited apoptosis, and promoted viral replication. Finally, we showed that DPV infection can cause cell cycle S-phase arrest. Conclusions: This study shows that DPV causes cell cycle S-phase arrest and leads to apoptosis through caspase activation and increased intracellular ROS levels. These findings may be useful for gaining an understanding of the pathogenesis of DPV and the apoptotic pathways induced by α-herpesviruses.

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RGNNV-induced cell cycle arrest at G1/S phase enhanced viral replication via p53-dependent pathway in GS cells

Virus Research ◽

10.1016/j.virusres.2018.06.011 ◽

2018 ◽

Vol 256 ◽

pp. 142-152 ◽

Cited By ~ 3

Author(s):

Weijun Mai ◽

Hongxiao Liu ◽

Huiqing Chen ◽

Yajing Zhou ◽

Yan Chen

Keyword(s):

Cell Cycle ◽

Viral Replication ◽

Cell Cycle Arrest ◽

S Phase ◽

Cycle Arrest ◽

Dependent Pathway

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Legionella pneumophila translocated translation inhibitors are required for bacterial-induced host cell cycle arrest

10.1101/479915 ◽

2018 ◽

Author(s):

Asaf Sol ◽

Erion Lipo ◽

Dennise A. de Jesús ◽

Connor Murphy ◽

Mildred Devereux ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Host Cell ◽

Legionella Pneumophila ◽

Cell Cycle Progression ◽

S Phase ◽

Cycle Progression ◽

Cycle Arrest ◽

Bacterial Replication ◽

Cell Cycle Machinery

AbstractThe cell cycle machinery controls diverse cellular pathways and is tightly regulated. Misregulation of cell division plays a central role in the pathogenesis of many disease processes. Various microbial pathogens interfere with the cell cycle machinery to promote host cell colonization. Although cell cycle modulation is a common theme among pathogens, the role that this interference plays in promoting diseases is unclear. Previously we demonstrated that the G1 and G2/M phases of the host cell cycle are permissive for Legionella pneumophila replication, while S phase provides a toxic environment for bacterial replication. In this study we show that L. pneumophila avoids host S phase by blocking host DNA synthesis and preventing cell cycle progression into S phase. Cell cycle arrest upon Legionella contact is dependent on the Icm/Dot secretion system. In particular, we found that cell cycle arrest is dependent on the intact enzymatic activity of translocated substrates that inhibits host translation. Moreover, we show that early in infection, the presence of these translation inhibitors is crucial to induce the degradation of the master regulator cyclin D1. Our results demonstrate that the bacterial effectors that inhibit translation are associated with preventing entry of host cells into a phase associated with restriction of L. pneumophila. Furthermore, control of cyclin D1 may be a common strategy used by intracellular pathogens to manipulate the host cell cycle and promote bacterial replication.SignificanceRecently, we showed that host cell cycle regulatory proteins control L. pneumophila growth. In particular, bacterial replication was found to be depressed in S-phase. This indicates that bacterial control of the host cell cycle can limit exposure of the pathogen to antimicrobial events that are cycle-specific. Here we uncovered bacterial factors that induce host cell cycle arrest by inhibiting host protein synthesis and preventing S phase transition. These data are consistent with S-phase toxicity serving as an important antimicrobial response that limits growth of some intracellular pathogens. Moreover, identification of microbial factors that block cell cycle progression and uncovering host cell cycle partners are candidates for future drug development. Our data point to a unifying role of the cell cycle in multiple disease processes.

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Molecular Mechanisms of Thymoquinone as Anticancer agent

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323999201027225305 ◽

2020 ◽

Vol 23 ◽

Author(s):

Fatma Ismail Alhmied ◽

Ali Hassan Alammar ◽

Bayan Mohammed Alsultan ◽

Marooj Alshehri ◽

Faheem Hyder Pottoo

Keyword(s):

Breast Cancer ◽

Cell Cycle ◽

Cell Cycle Arrest ◽

Human Breast Cancer ◽

Phase Cell ◽

Cycle Phase ◽

Human Breast ◽

Cycle Arrest ◽

Phase Arrest ◽

Anti Cancer

Abstract:: Thymoquinone (TQ), the bioactive constituent of Nigella Sativa seeds is a well-known natural compound for the management of several types of cancers. The anti-cancer properties of thymoquinone are thought to be operated via intervening with various oncogenic pathways including cell cycle arrest, prevention of inflammation and oxidative stress, induction of invasion, metastasis, inhibition of angiogenesis, and apoptosis. As well as up-regulation and down-regulation of specific tumor suppressor genes and tumor promoting genes, respectively. Proliferation of various tumor cells is inhibited by TQ via induction of cell cycle arrest, disruption of the microtubule organization, and down regulating cell survival protein expression. TQ induces G1 phase cell cycle arrest in human breast cancer, colon cancer and osteosarcoma cells through inhibiting the activation of cyclin E or cyclin D and up-regulating p27and p21 a cyclin dependent kinase (Cdk) inhibitor. TQ concentration is a significant factor in targeting a particular cell cycle phase. While high concentration of TQ induced G2 phase arrest in human breast cancer (MCF-7) cells, low concentration causes S phase arrest. This review article provides mechanistic insights into the anti-cancer properties of thymoquinone.

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