Human Cytomegalovirus miR-UL70-3p Downregulates the H2O2-Induced Apoptosis by Targeting the Modulator of Apoptosis-1 (MOAP1)

Human Cytomegalovirus (HCMV) is a prototypic beta herpesvirus, causing persistent infections in humans. There are medications that are used to treat the symptoms; however, there is no cure yet. Thus, understanding the molecular mechanisms of HCMV replication and its persistence may reveal new prevention strategies. HCMV evasive strategies on the antiviral responses of the human host largely rely on its significant portion of genome. Numerous studies have highlighted the importance of miRNA-mediated regulation of apoptosis, which is an innate immune mechanism that eradicates virus-infected cells. In this study, we explore the antiapoptotic role of hcmv-miR-UL70-3p in HEK293T cells. We establish that hcmv-miR-UL70-3p targets the proapoptotic gene Modulator of Apoptosis-1 (MOAP1) through interaction with its 3’UTR region of mRNA. The ectopic expression of hcmv-miR-UL70-3p mimic significantly downregulates the H2O2-induced apoptosis through the translational repression of MOAP1. Silencing of MOAP1 through siRNA also inhibits the H2O2-induced apoptosis, which further supports the hcmv-miR-UL70-3p mediated antiapoptotic effect by regulating MOAP1 expression. These results uncover a role for hcmv-miR-UL70-3p and its target MOAP1 in regulating apoptosis.

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Role of nucleotide-binding oligomerization domain 1 (NOD1) and its variants in human cytomegalovirus control in vitro and in vivo

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1611711113 ◽

2016 ◽

Vol 113 (48) ◽

pp. E7818-E7827 ◽

Cited By ~ 15

Author(s):

Yi-Hsin Fan ◽

Sujayita Roy ◽

Rupkatha Mukhopadhyay ◽

Arun Kapoor ◽

Priya Duggal ◽

...

Keyword(s):

Virus Replication ◽

Human Cytomegalovirus ◽

Nucleotide Binding ◽

Virus Growth ◽

Antiviral Responses ◽

Hcmv Replication ◽

Oligomerization Domain ◽

In Cells

Induction of nucleotide-binding oligomerization domain 2 (NOD2) and downstream receptor-interacting serine/threonine-protein kinase 2 (RIPK2) by human cytomegalovirus (HCMV) is known to up-regulate antiviral responses and suppress virus replication. We investigated the role of nucleotide-binding oligomerization domain 1 (NOD1), which also signals through RIPK2, in HCMV control. NOD1 activation by Tri-DAP (NOD1 agonist) suppressed HCMV and induced IFN-β. Mouse CMV was also inhibited through NOD1 activation. NOD1 knockdown (KD) or inhibition of its activity with small molecule ML130 enhanced HCMV replication in vitro. NOD1 mutations displayed differential effects on HCMV replication and antiviral responses. In cells overexpressing the E56K mutation in the caspase activation and recruitment domain, virus replication was enhanced, but in cells overexpressing the E266K mutation in the nucleotide-binding domain or the wild-type NOD1, HCMV was inhibited, changes that correlated with IFN-β expression. The interaction of NOD1 and RIPK2 determined the outcome of virus replication, as evidenced by enhanced virus growth in NOD1 E56K mutant cells (which failed to interact with RIPK2). NOD1 activities were executed through IFN-β, given that IFN-β KD reduced the inhibitory effect of Tri-DAP on HCMV. Signaling through NOD1 resulting in HCMV suppression was IKKα-dependent and correlated with nuclear translocation and phosphorylation of IRF3. Finally, NOD1 polymorphisms were significantly associated with the risk of HCMV infection in women who were infected with HCMV during participation in a glycoprotein B vaccine trial. Collectively, our data indicate a role for NOD1 in HCMV control via RIPK2- IKKα-IRF3 and suggest that its polymorphisms predict the risk of infection.

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Binding of the Human Cytomegalovirus (HCMV) Tegument Protein UL69 to UAP56/URH49 Is Not Required for Efficient Replication of HCMV

Journal of Virology ◽

10.1128/jvi.00669-10 ◽

2010 ◽

Vol 84 (18) ◽

pp. 9649-9654 ◽

Cited By ~ 6

Author(s):

Daniel Kronemann ◽

Stacy R. Hagemeier ◽

Dan Cygnar ◽

Stacia Phillips ◽

Wade A. Bresnahan

Keyword(s):

Human Cytomegalovirus ◽

Molecular Mechanisms ◽

Mrna Export ◽

Tegument Protein ◽

Viral Mrnas ◽

Viral Mutant ◽

Efficient Replication ◽

Infected Cells ◽

Hcmv Replication ◽

Efficient Viral Replication

ABSTRACT The human cytomegalovirus (HCMV) tegument protein UL69 is important for efficient viral replication at low multiplicities of infection. Several molecular mechanisms by which UL69 contributes to HCMV replication have been proposed, including UL69's ability to interact with the mRNA export factors UAP56 and URH49 to facilitate the shuttling of viral mRNAs from the nuclei of infected cells. Using a UL69 viral mutant that is unable to bind UAP56 and URH49, we demonstrated that UL69's interaction with UAP56 or URH49 does not contribute to the growth phenotype associated with the UL69 deletion mutant.

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The p53/miR-34a/SIRT1 Positive Feedback Loop in Quercetin-Induced Apoptosis

Cellular Physiology and Biochemistry ◽

10.1159/000374024 ◽

2015 ◽

Vol 35 (6) ◽

pp. 2192-2202 ◽

Cited By ~ 48

Author(s):

Guohua Lou ◽

Yanning Liu ◽

Shanshan Wu ◽

Jihua Xue ◽

Fan Yang ◽

...

Keyword(s):

Cell Apoptosis ◽

Feedback Loop ◽

Molecular Mechanisms ◽

Rt Pcr ◽

Cycle Arrest ◽

Anticancer Effects ◽

Huh7 Cells ◽

Mirnas Expression ◽

Induced Apoptosis

Background: The anti-tumor effects of quercetin have been reported, but the underlying molecular mechanisms remain to be elucidated. The aim of present study was to explore the role of miRNA in the anticancer effects of quercetin. Methods: The differential miRNAs expression between the HepG2 and Huh7 cells treated by quercetin were detected by microarray. The xCELLigence, Flow cytometry, RT-PCR and Western blot were used to analyze the cell proliferation, cell apoptosis, cell cycle arrest, anti-tumor genes, and protein expression. Results: miR-34a was up-regulated in HepG2 cells treated by quercetin exhibiting wild-type p53. When inhibiting the miR-34a, the sensitivity of the cells to quercetin decreased and the expression of the SIRT1 was up-regulated, but the acetylation of p53 and the expression of some genes related to p53 down-regulated. Conclusion: miR-34a plays an important role in the anti-tumor effects of querctin in HCC, miR-34a may be a tiemolecule between the p53 and SIRT1 and is composed of a p53/miR-34a/SIRT1 signal feedback loop, which could enhance apoptosis signal and significantly promote cell apoptosis.

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A novel calcium-concentrating compartment drives biofilm formation and persistent infections

10.1101/2020.01.08.898569 ◽

2020 ◽

Author(s):

Alona Keren-Paz ◽

Malena Cohen-Cymberknoh ◽

Dror Kolodkin-Gal ◽

Iris Karunker ◽

Simon Dersch ◽

...

Keyword(s):

Biofilm Formation ◽

Calcium Uptake ◽

Molecular Mechanisms ◽

Model Organism ◽

Bacterial Cells ◽

Mineral Layer ◽

Cellular Compartment ◽

Persistent Infections ◽

Cellular Metal

AbstractBacterial biofilms produce a robust internal mineral layer, composed of calcite, which strengthens the colony and protects the residing bacteria from antibiotics. In this work, we provide evidence that the assembly of a functional mineralized macro-structure begins with mineral precipitation within a defined cellular compartment in a differentiated subpopulation of cells. Transcriptomic analysis of a model organism, Bacillus subtilis, revealed that calcium was essential for activation of the biofilm state, and highlighted the role of cellular metal homeostasis and carbon metabolism in biomineralization. The molecular mechanisms promoting calcite formation were conserved in pathogenic Pseudomonas aeruginosa biofilms, resulting in formation of calcite crystals tightly associated with bacterial cells in sputum samples collected from cystic fibrosis patients. Biomineralization inhibitors targeting calcium uptake and carbonate accumulation significantly reduced the damage inflicted by P. aeruginosa biofilms to lung tissues. Therefore, better understanding of the conserved molecular mechanisms promoting biofilm calcification can path the way to the development of novel classes of antibiotics to combat otherwise untreatable biofilm infections.

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SPNS2 Downregulation Induces EMT and Promotes Colorectal Cancer Metastasis via Activating AKT Signaling Pathway

Frontiers in Oncology ◽

10.3389/fonc.2021.682773 ◽

2021 ◽

Vol 11 ◽

Author(s):

Lei Lv ◽

Qiyi Yi ◽

Ying Yan ◽

Fengmei Chao ◽

Ming Li

Keyword(s):

Colorectal Cancer ◽

Molecular Mechanisms ◽

Cancer Metastasis ◽

Epithelial Mesenchymal Transition ◽

Ectopic Expression ◽

Migration And Invasion ◽

Akt Inhibitor ◽

Colon Adenoma ◽

Mesenchymal Transition

Spinster homologue 2 (SPNS2), a transporter of S1P (sphingosine-1-phosphate), has been reported to mediate immune response, vascular development, and pathologic processes of diseases such as cancer via S1P signaling pathways. However, its biological functions and expression profile in colorectal cancer (CRC) is elusive. In this study, we disclosed that SPNS2 expression, which was regulated by copy number variation and DNA methylation of its promoter, was dramatically upregulated in colon adenoma and CRC compared to normal tissues. However, its expression was lower in CRC than in colon adenoma, and low expression of SPN2 correlated with advanced T/M/N stage and poor prognosis in CRC. Ectopic expression of SPNS2 inhibited cell proliferation, migration, epithelial–mesenchymal transition (EMT), invasion, and metastasis in CRC cell lines, while silencing SPNS2 had the opposite effects. Meanwhile, measuring the intracellular and extracellular level of S1P after overexpression of SPNS2 pinpointed a S1P-independent model of SPNS2. Mechanically, SPNS2 led to PTEN upregulation and inactivation of Akt. Moreover, AKT inhibitor (MK2206) abrogated SPNS2 knockdown-induced promoting effects on the migration and invasion, while AKT activator (SC79) reversed the repression of migration and invasion by SPNS2 overexpression in CRC cells, confirming the pivotal role of AKT for SPNS2’s function. Collectively, our study demonstrated the suppressor role of SPNS2 during CRC metastasis, providing new insights into the pathology and molecular mechanisms of CRC progression.

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Dengue activates mTORC2 signaling to counteract apoptosis and maximize viral replication

10.1101/2020.09.22.308890 ◽

2020 ◽

Author(s):

Christoph C. Carter ◽

Jean Paul Olivier ◽

Alexis Kaushansky ◽

Fred D. Mast ◽

John D. Aitchison

Keyword(s):

Viral Replication ◽

Cell Survival ◽

Structural Protein ◽

Protein Protein Interaction ◽

Mechanistic Target Of Rapamycin ◽

Promote Cell Survival ◽

Important Regulator ◽

Infected Cells ◽

Induced Apoptosis

ABSTRACTThe mechanistic target of rapamycin (mTOR) functions in at least two distinct complexes: mTORC1, which regulates cellular anabolic-catabolic homeostasis, and mTORC2, which is an important regulator of cell survival and cytoskeletal maintenance. mTORC1 has been implicated in the pathogenesis of flaviviruses including dengue, where it contributes to the establishment of a pro-viral autophagic state. In contrast, the role of mTORC2 in viral pathogenesis is unknown. In this study, we explore the consequences of a physical protein-protein interaction between dengue non-structural protein 5 (NS5) and host cell mTOR proteins during infection. Using shRNA to differentially target mTORC1 and mTORC2 complexes, we show that mTORC2 is required for optimal dengue replication. Furthermore, we show that mTORC2 is activated during viral replication, and that mTORC2 counteracts virus-induced apoptosis, promoting the survival of infected cells. This work reveals a novel mechanism by which the dengue flavivirus can promote cell survival to maximize viral replication.

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Linc00426 accelerates lung adenocarcinoma progression by regulating miR-455-5p as a molecular sponge

Cell Death and Disease ◽

10.1038/s41419-020-03259-2 ◽

2020 ◽

Vol 11 (12) ◽

Author(s):

Hongli Li ◽

Qingjie Mu ◽

Guoxin Zhang ◽

Zhixin Shen ◽

Yuanyuan Zhang ◽

...

Keyword(s):

Lung Adenocarcinoma ◽

Molecular Mechanisms ◽

Epithelial Mesenchymal Transition ◽

Ectopic Expression ◽

Tumor Development ◽

Biological Significance ◽

Mesenchymal Transition

AbstractIncreasing lines of evidence indicate the role of long non-coding RNAs (LncRNAs) in gene regulation and tumor development. Hence, it is important to elucidate the mechanisms of LncRNAs underlying the proliferation, metastasis, and invasion of lung adenocarcinoma (LUAD). We employed microarrays to screen LncRNAs in LUAD tissues with and without lymph node metastasis and revealed their effects on LUAD. Among them, Linc00426 was selected for further exploration in its expression, the biological significance, and the underlying molecular mechanisms. Linc00426 exhibits ectopic expression in LUAD tissues and cells. The ectopic expression has been clinically linked to tumor size, lymphatic metastasis, and tumor differentiation of patients with LUAD. The deregulation of Linc00426 contributes to a notable impairment in proliferation, invasion, metastasis, and epithelial–mesenchymal transition (EMT) in vitro and in vivo. Mechanistically, the deregulation of Linc00426 could reduce cytoskeleton rearrangement and matrix metalloproteinase expression. Meanwhile, decreasing the level of Linc00426 or increasing miR-455-5p could down-regulate the level of UBE2V1. Thus, Linc00426 may act as a competing endogenous RNA (ceRNA) to abate miR-455-5p-dependent UBE2V1 reduction. We conclude that Linc00426 accelerates LUAD progression by acting as a molecular sponge to regulate miR-455-5p, and may be a potential novel tumor marker for LUAD.

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The Human Cytomegalovirus UL51 Protein Is Essential for Viral Genome Cleavage-Packaging and Interacts with the Terminase Subunits pUL56 and pUL89

Journal of Virology ◽

10.1128/jvi.01955-12 ◽

2012 ◽

Vol 87 (3) ◽

pp. 1720-1732 ◽

Cited By ~ 55

Author(s):

Eva Maria Borst ◽

Jennifer Kleine-Albers ◽

Ildar Gabaev ◽

Marina Babić ◽

Karen Wagner ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Unit Length ◽

Viral Proteins ◽

Enzymatic Process ◽

Genome Packaging ◽

Subnuclear Localization ◽

Promising Target ◽

Synthetic Ligand ◽

Infected Cells ◽

Hcmv Replication

ABSTRACTCleavage of human cytomegalovirus (HCMV) genomes as well as their packaging into capsids is an enzymatic process mediated by viral proteins and therefore a promising target for antiviral therapy. The HCMV proteins pUL56 and pUL89 form the terminase and play a central role in cleavage-packaging, but several additional viral proteins, including pUL51, had been suggested to contribute to this process, although they remain largely uncharacterized. To study the function of pUL51 in infected cells, we constructed HCMV mutants encoding epitope-tagged versions of pUL51 and used a conditionally replicating virus (HCMV-UL51-ddFKBP), in which pUL51 levels could be regulated by a synthetic ligand. In cells infected with HCMV-UL51-ddFKBP, viral DNA replication was not affected when pUL51 was knocked down. However, no unit-length genomes and no DNA-filled C capsids were found, indicating that cleavage of concatemeric HCMV DNA and genome packaging into capsids did not occur in the absence of pUL51. pUL51 was expressed mainly with late kinetics and was targeted to nuclear replication compartments, where it colocalized with pUL56 and pUL89. Upon pUL51 knockdown, pUL56 and pUL89 were no longer detectable in replication compartments, suggesting that pUL51 is needed for their correct subnuclear localization. Moreover, pUL51 was found in a complex with the terminase subunits pUL56 and pUL89. Our data provide evidence that pUL51 is crucial for HCMV genome cleavage-packaging and may represent a third component of the viral terminase complex. Interference with the interactions between the terminase subunits by antiviral drugs could be a strategy to disrupt the HCMV replication cycle.

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The Clinically Approved Antifungal Drug Posaconazole Inhibits Human Cytomegalovirus Replication

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00056-20 ◽

2020 ◽

Vol 64 (10) ◽

Author(s):

Beatrice Mercorelli ◽

Anna Luganini ◽

Marta Celegato ◽

Giorgio Palù ◽

Giorgio Gribaudo ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Fungal Infections ◽

Antimicrobial Effect ◽

Virus Particles ◽

Human Cytochrome ◽

Passage Number ◽

Infected Cells ◽

Hcmv Replication ◽

Different Strains ◽

Low Passage

ABSTRACT Posaconazole (PCZ) is a clinically approved drug used predominantly for prophylaxis and salvage therapy of fungal infections. Here, we report its previously undescribed anti-human cytomegalovirus (HCMV) activity. By using antiviral assays, we demonstrated that PCZ, along with other azolic antifungals, has a broad anti-HCMV activity, being active against different strains, including low-passage-number clinical isolates and strains resistant to viral DNA polymerase inhibitors. Using a pharmacological approach, we identified the inhibition of human cytochrome P450 51 (hCYP51), or lanosterol 14α demethylase, a cellular target of posaconazole in infected cells, as a mechanism of anti-HCMV activity of the drug. Indeed, hCYP51 expression was stimulated upon HCMV infection, and the inhibition of its enzymatic activity by either the lanosterol analog VFV {(R)-N-(1-(3,4′-difluoro-[1,1′-biphenyl]-4-yl)-2-(1H-imidazol-1-yl)ethyl)-4-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamide} or PCZ decreased HCMV yield and infectivity of released virus particles. Importantly, we observed that the activity of the first-line anti-HCMV drug ganciclovir was boosted tenfold by PCZ and that ganciclovir (GCV) and PCZ act synergistically in inhibiting HCMV replication. Taken together, these findings suggest that this clinically approved drug deserves further investigation in the development of host-directed antiviral strategies as a candidate anti-HCMV drug with a dual antimicrobial effect.

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SENP1-Mediated Desumoylation of DBC1 Inhibits Apoptosis Induced by High Glucose in Bovine Retinal Pericytes

Journal of Ophthalmology ◽

10.1155/2016/6392658 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11

Author(s):

Jian Gao ◽

Xia Chen ◽

Qing Gu ◽

Xiaoxiao Liu ◽

Xun Xu

Keyword(s):

Diabetic Retinopathy ◽

High Glucose ◽

Molecular Mechanisms ◽

Characteristic Change ◽

High Concentration ◽

Retinal Pericytes ◽

Specific Protease ◽

Induced Apoptosis ◽

Pericyte Loss

Pericyte loss is an early characteristic change in diabetic retinopathy, but its precise molecular mechanisms have not been elucidated. This study investigated the role of SENP1 in pericyte loss in diabetic retinopathy. We demonstrated that a high concentration of glucose inhibited the expression of the Sentrin/SUMO-specific protease 1 (SENP1), which resulted in an increase in DBC1 sumoylation in bovine retinal pericytes (BRPCs). Furthermore, SENP1 overexpression attenuated hyperemia-induced apoptosis of BPRCs, and SENP1 knockdown aggravated this effect. We also provide evidence that DBC1 sumoylation/desumoylation is involved in the SENP1-regulated apoptosis of BRPCs under high glucose conditions. Understanding the role of SENP1 in the pathogenesis of high glucose induced pericyte loss could help elucidate important targets for future pharmacological interventions.

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