scholarly journals Human Cytomegalovirus Mir-UL70-3p Downregulates the H2O2 Induced Apoptosis in HEK293T Cells by Targeting the Modulator of Apoptosis-1 (MOAP1)

2021 ◽  
Author(s):  
Abhishek Pandeya ◽  
Anup Mishra ◽  
Raj Kumar Khalko ◽  
Sukhveer Singh ◽  
Nishant Singh ◽  
...  
Keyword(s):  
Human Cytomegalovirus ◽  
Cellular Response ◽  
Opportunistic Infections ◽  
Ectopic Expression ◽  
Developed Countries ◽  
Productive Infection ◽  
Protein Levels ◽  
Apoptosis Protein ◽  
Cellular Apoptosis ◽  
Induced Apoptosis

Abstract Human Cytomegalovirus (HCMV), a prototypic member of the Beta-herpesvirinae subfamily, mainly responsible for congenital disabilities in newborns, cause opportunistic infections in immunocompromised individuals. Its seroprevalence varies across the globe ranging from 50–70 percent in developed countries to 90–100 percent in developing countries. Causing latent infections in the immunocompetent host suggests that it employs several strategies to escape the wrath of the host’s antiviral mechanisms. Apoptosis is an innate cellular response to viral infection, and downregulation of this mechanism by HCMV is a well-established phenomenon. HCMV utilizes its proteins, RNA and miRNA in regulating this response to establish a productive infection in the host. The role of HCMV miRNAs on cellular apoptosis is very interesting, where some miRNAs downregulate but a few upregulate this process. In the present study, we report the antiapoptotic activity of HCMV miRNA, miR-UL-70-3p, on H2O2 induced apoptosis in HEK293T cells. The ectopic expression of this HCMV miRNA in HEK293T cells downregulate the apoptosis, and continuing studies reveal that the proapoptotic gene, Modulator of Apoptosis Protein-1 (MOAP1), is a functional target for this miRNA. We verified the functionality of the binding site predicted in the 3'UTR of MOAP1 in our earlier studies through dual luciferase-based assays using both the wild and mutant 3'UTR’s of MOAP1. The MOAP1 protein levels were significantly downregulated by the miR-UL70-3p, suggesting that the MOAP1 mRNA was degraded after binding with the miR-UL70-3p. Further, the extent of MOAP1 mRNA and its protein inhibitions by HCMV miR-UL70-3p and siRNA of MOAP1 were compared and found that the siRNA of MOAP1 inhibits 69.52 percent of mRNA and 35.67 percent of MOAP1 protein; while the miR-UL70-3p inhibits 46.66 percent MOAP1 mRNA and 21.05 percent MOAP1 protein. Though the inhibitory activity of miR-UL70-3p is not equal to the siRNA of MOAP1, but it was significant enough in reversing the H2O2 induced apoptosis in HEK293T cells. These results confirm that hcmv-miR-UL70-3p downregulates H2O2 induced apoptosis in HEK293T cells by targeting the 3'UTR of MOAP1 mRNA.

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

2021 ◽  
Vol 23 (1) ◽  
pp. 18
Author(s):  
Abhishek Pandeya ◽  
Raj Kumar Khalko ◽  
Anup Mishra ◽  
Nishant Singh ◽  
Sukhveer Singh ◽  
...  
Keyword(s):  
Human Cytomegalovirus ◽  
Molecular Mechanisms ◽  
Ectopic Expression ◽  
Antiviral Responses ◽  
Persistent Infections ◽  
Innate Immune Mechanism ◽  
Infected Cells ◽  
Hcmv Replication ◽  
Induced Apoptosis

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.

scholarly journals Honokiol Enhances TRAIL-Mediated Apoptosis through STAMBPL1-Induced Survivin and c-FLIP Degradation

Biomolecules ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 838 ◽  
Author(s):  
Seon Min Woo ◽  
Seung Un Seo ◽  
Peter Kubatka ◽  
Kyoung-jin Min ◽  
Taeg Kyu Kwon
Keyword(s):  
Chinese Medicine ◽  
Cancer Cells ◽  
Tumor Necrosis ◽  
Biological Effects ◽  
Ectopic Expression ◽  
Protein Levels ◽  
Anti Cancer ◽  
Trail Resistance ◽  
Induced Apoptosis ◽  
Necrosis Factor

Honokiol is a natural biphenolic compound extracted from traditional Chinese medicine Magnolia species, which have been known to display various biological effects including anti-cancer, anti-proliferative, anti-angiogenic, and anti-metastatic activities in cancer cells. Here, we found that honokiol sensitizes cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis through downregulation of anti-apoptotic proteins survivin and c-FLIP. Ectopic expression of survivin and c-FLIP markedly abolished honokiol and TRAIL-induced apoptosis. Mechanistically, honokiol induced protein degradation of c-FLIP and survivin through STAMBPL1, a deubiquitinase. STAMBPL1 interacted with survivin and c-FLIP, resulted in reduction of ubiquitination. Knockdown of STAMBPL1 reduced survivin and c-FLIP protein levels, while overexpression of STAMBPL1 inhibited honokinol-induced survivin and c-FLIP degradation. Our findings provided that honokiol could overcome TRAIL resistance through survivin and c-FLIP degradation induced by inhibition of STAMBPL1 expression.

scholarly journals Involvement of Up-Regulation of DR5 Expression and Down-Regulation of c-FLIP in Niclosamide-Mediated TRAIL Sensitization in Human Renal Carcinoma Caki Cells

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2264 ◽  
Author(s):  
Jeong Yun ◽  
Seon Woo ◽  
Seung Seo ◽  
Kyoung-Jin Min ◽  
Dong Kim ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Surface ◽  
Apoptotic Cell ◽  
Ectopic Expression ◽  
Down Regulation ◽  
Protein Levels ◽  
Parasite Infections ◽  
Trail Resistance ◽  
Induced Apoptosis ◽  
Interfering Rna

Niclosamide is used to treat intestinal parasite infections, as being an anthelmintic drug. Recently, several papers suggest the niclosamide inhibits multiple signaling pathways, which are highly activated and mutated in cancer. Here, niclosamide was evaluated for identifying strategies to overcome tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance. Although niclosamide (100–200 nM) alone did not bring about cell death, combinations of niclosamide and TRAIL led to apoptotic cell death in carcinoma cells, but not in normal cells. Niclosamide markedly increased DR5 protein levels, including cell-surface DR5, and decreased c-FLIP protein levels. Down-regulation of DR5 by specific small interfering RNA (siRNA) and ectopic expression of c-FLIP markedly blocked niclosamide plus TRAIL-induced apoptosis. Our findings provide that niclosamide could overcome resistance to TRAIL through up-regulating DR5 on the cell surface and down-regulating c-FLIP in cancer cells. Taken together, niclosamide may be an attractive candidate to overcome TRAIL resistance.

scholarly journals STAT3-mediated transcription of Bcl-2, Mcl-1 and c-IAP2 prevents apoptosis in polyamine-depleted cells

2005 ◽  
Vol 392 (2) ◽  
pp. 335-344 ◽  
Author(s):  
Sujoy Bhattacharya ◽  
Ramesh M. Ray ◽  
Leonard R. Johnson
Keyword(s):  
Myeloid Cell ◽  
Dominant Negative ◽  
Cell Leukaemia ◽  
Cell Periphery ◽  
Inhibitory Peptide ◽  
Protein Levels ◽  
Tnf Α ◽  
Apoptosis Protein ◽  
Before And After ◽  
Induced Apoptosis

Activation of STAT3 (signal transducer and activator of transcription 3) plays a crucial role in cell survival and proliferation. The aim of the present study was to clarify the role of STAT3 signalling in the protection of polyamine-depleted intestinal epithelial cells against TNF-α (tumour necrosis factor-α)-induced apoptosis. Polyamine depletion by DFMO (α-difluoromethylornithine) caused phosphorylation of STAT3 at Tyr-705 and Ser-727. Phospho-Tyr-705 STAT3 was immunolocalized at the cell periphery and nucleus, whereas phospho-Ser-727 STAT3 was predominantly detected in the nucleus of polyamine-depleted cells. Sustained phosphorylation of STAT3 at tyrosine residues was observed in polyamine-depleted cells after exposure to TNF-α. Inhibition of STAT3 activation by AG490 or cell-membrane-permeant inhibitory peptide (PpYLKTK; where pY represents phospho-Tyr) increased the sensitivity of polyamine-depleted cells to apoptosis. Expression of DN-STAT3 (dominant negative-STAT3) completely eliminated the protective effect of DFMO against TNF-α-induced apoptosis. Polyamine depletion increased mRNA and protein levels for Bcl-2, Mcl-1 (myeloid cell leukaemia-1) and c-IAP2 (inhibitor of apoptosis protein-2). Significantly higher levels of Bcl-2 and c-IAP2 proteins were observed in polyamine-depleted cells before and after 9 h of TNF-α treatment. Inhibition of STAT3 by AG490 and DN-STAT3 decreased Bcl-2 promoter activity. DN-STAT3 decreased mRNA and protein levels for Bcl-2, Mcl-1 and c-IAP2 in polyamine-depleted cells. siRNA (small interfering RNA)-mediated inhibition of Bcl-2, Mcl-1 and c-IAP2 protein levels increased TNF-α-induced apoptosis. DN-STAT3 induced the activation of caspase-3 and PARP [poly(ADP-ribose) polymerase] cleavage in polyamine-depleted cells. These results suggest that activation of STAT3 in response to polyamine depletion increases the transcription and subsequent expression of anti-apoptotic Bcl-2 and IAP family proteins and thereby promotes survival of cells against TNF-α-induced apoptosis.

scholarly journals PI3K–AKT Pathway Protects Cardiomyocytes Against Hypoxia-Induced Apoptosis by MitoKATP-Mediated Mitochondrial Translocation of pAKT

2018 ◽  
Vol 49 (2) ◽  
pp. 717-727 ◽  
Author(s):  
Hua-Pei Song ◽  
Zhi-Gang Chu ◽  
Dong-Xia Zhang ◽  
Yong-Ming Dang ◽  
Qiong Zhang
Keyword(s):  
Molecular Mechanisms ◽  
Signal Pathway ◽  
Akt Pathway ◽  
Phosphatidylinositol 3 Kinase ◽  
Mitochondrial Translocation ◽  
Protein Levels ◽  
Apoptotic Effect ◽  
Cellular Apoptosis ◽  
Intracellular Signal ◽  
Induced Apoptosis

Background/Aims: The phosphatidylinositol-3-kinase -AKT (PI3K-AKT) is an important intracellular signal pathway in regulating cell proliferation, differentiation and apoptosis. In previous studies, we’ve demonstrated that PI3K–AKT pathway protects cardiomyocytes from ischemic and hypoxic apoptosis through mitochondrial function. However, the molecular mechanisms underlying hypoxia-induced cardiomyocyte apoptosis via PI3K-AKT pathway remain ill-defined. Here, we addressed this question. Methods: Cardiomyocytes were exposed to hypoxia, with/without different inhibitors and then protein levels were assessed by Western blotting. Results: We found that the PI3K–AKT pathway was activated in cardiomyocytes that were exposed to hypoxia. Moreover, the phospho-AKT (pAKT) translocated from cytosol to mitochondria via mitochondrial adenosine triphosphate-dependent potassium (mitoKATP), leading to an increase in cytochrome c oxidase (CcO) activity to suppress apoptosis. On the other hand, the mitoKATP specific blocker, 5-hydroxydecanote (5-HD), or suppression of CcO using siRNA, inhibited the pAKT mitochondrial translocation to maintain the CcO activity, resulting in mitochondrial dysfunction and cellular apoptosis induced by hypoxia. Conclusion: These findings suggest that the anti-apoptotic effect of the PI3K-AKT pathway through pAKT translocation to mitochondrial via mitoKATP may be conducted through modification of CcO activity.

scholarly journals Pirh2, an E3 ligase, regulates the AIP4–p73 regulatory pathway by modulating AIP4 expression and ubiquitination

2021 ◽  
Author(s):  
Rami Abou Zeinab ◽  
H Helena Wu ◽  
Yasser Abuetabh ◽  
Sarah Leng ◽  
Consolato Sergi ◽  
...  
Keyword(s):  
Regulatory Protein ◽  
Ectopic Expression ◽  
E3 Ligase ◽  
Regulatory Pathway ◽  
Hect Domain ◽  
E3 Ligases ◽  
Multiple Substrates ◽  
Protein Levels ◽  
Cycle Arrest ◽  
Negative Regulatory Pathway

Abstract Pirh2 is an E3 ligase belonging to the RING-H2 family and shown to bind, ubiquitinate and downregulate p73 tumor suppressor function without altering p73 protein levels. AIP4, an E3 ligase belonging to the HECT domain family, has been reported to be a negative regulatory protein that promotes p73 ubiquitination and degradation. Herein, we found that Pirh2 is a key regulator of AIP4 that inhibits p73 function. Pirh2 physically interacts with AIP4 and significantly downregulates AIP4 expression. This downregulation is shown to involve the ubiquitination of AIP4 by Pirh2. Importantly, we demonstrated that the ectopic expression of Pirh2 inhibits the AIP4–p73 negative regulatory pathway, which was restored when depleting endogenous Pirh2 utilizing Pirh2-siRNAs. We further observed that Pirh2 decreases AIP4-mediated p73 ubiquitination. At the translational level and specifically regarding p73 cell cycle arrest function, Pirh2 still ensures the arrest of p73-mediated G1 despite AIP4 expression. Our study reveals a novel link between two E3 ligases previously thought to be unrelated in regulating the same effector substrate, p73. These findings open a gateway to explain how E3 ligases differentiate between regulating multiple substrates that may belong to the same family of proteins, as it is the case for the p53 and p73 proteins.

scholarly journals Regulation of Krüppel-Like Factor 15 Expression by Herpes Simplex Virus Type 1 or Bovine Herpesvirus 1 Productive Infection

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1148
Author(s):  
Fouad S. El-mayet ◽  
Kelly S. Harrison ◽  
Clinton Jones
Keyword(s):  
Steady State ◽  
Promoter Activity ◽  
Bovine Herpesvirus ◽  
Productive Infection ◽  
Bovine Herpesvirus 1 ◽  
Protein Levels ◽  
Herpesvirus 1 ◽  
Simplex Virus ◽  
Hsv 1

Expression of Krüppel-like factor 15 (KLF15), a stress-induced transcription factor, is induced during bovine herpesvirus 1 (BoHV-1) reactivation from latency, and KLF15 stimulates BoHV-1 replication. Transient transfection studies revealed that KLF15 and glucocorticoid receptor (GR) cooperatively transactivate the BoHV-1-immediate-early transcription unit 1 (IEtu1), herpes simplex virus type 1 (HSV-1) infected cell protein 0 (ICP0), and ICP4 promoters. The IEtu1 promoter drives expression of bICP0 and bICP4, two key BoHV-1 transcriptional regulatory proteins. Based on these studies, we hypothesized infection is a stressful stimulus that increases KLF15 expression and enhances productive infection. New studies demonstrated that silencing KLF15 impaired HSV-1 productive infection, and KLF15 steady-state protein levels were increased at late stages of productive infection. KLF15 was primarily localized to the nucleus following infection of cultured cells with HSV-1, but not BoHV-1. When cells were transfected with a KLF15 promoter construct and then infected with HSV-1, promoter activity was significantly increased. The ICP0 gene, and to a lesser extent, bICP0 transactivated the KLF15 promoter in the absence of other viral proteins. In contrast, BoHV-1 or HSV-1 encoded VP16 had no effect on KLF15 promoter activity. Collectively, these studies revealed that HSV-1 and BoHV-1 productive infection increased KLF15 steady-state protein levels, which correlated with increased virus production.

scholarly journals MiR-489-3p inhibits cell proliferation, migration, and invasion, and induces apoptosis, by targeting the BDNF-mediated PI3K/AKT pathway in glioblastoma

2020 ◽  
Vol 15 (1) ◽  
pp. 274-283
Author(s):  
Bo Zheng ◽  
Tao Chen
Keyword(s):  
Cell Proliferation ◽  
Luciferase Reporter ◽  
Akt Pathway ◽  
Migration And Invasion ◽  
Bdnf Mrna ◽  
Protein Levels ◽  
Rna Immunoprecipitation ◽  
Underlying Mechanisms ◽  
Induced Apoptosis ◽  
Protein Cell

AbstractAmong astrocyte tumors, glioblastoma (GBM) is the most malignant glioma, highly aggressive and invasive, with extremely poor prognosis. Previous research has reported that microRNAs (miRNAs) participate in the progression of many cancers. Thus, this study aimed to explore the role and the underlying mechanisms of microRNA (miR)-489-3p in GBM progression. The expression of miR-489-3p and brain-derived neurotrophic factor (BDNF) mRNA was measured by quantitative real-time polymerase chain reaction. Western blot analysis was used to detect BDNF protein and the PI3K/AKT pathway-related protein. Cell proliferation, apoptosis, migration, and invasion were analyzed using CKK-8 assay, flow cytometry, and transwell assay, respectively. The interaction between BDNF and miR-489-3p was explored by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. MiR-489-3p was down-regulated and BDNF was up-regulated in GBM tissues and cells. MiR-489-3p re-expression or BDNF knockdown inhibited GBM cell proliferation, migration, and invasion, and promoted apoptosis. BDNF was a target of miR-489-3p, and BDNF up-regulation reversed the effects of miR-489-3p on GBM cells. The protein levels of p-AKT and p-PI3K were notably reduced in GBM cells by overexpression of miR-489-3p, but were rescued following BDNF up-regulation. Therefore, miR-489-3p inhibited proliferation, migration, and invasion, and induced apoptosis, by targeting the BDNF-mediated PI3K/AKT pathway in GBM, providing new strategies for clinical treatment of GBM.

scholarly journals PBRM1 Cooperates with YTHDF2 to Control HIF-1α Protein Translation

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1425
Author(s):  
Alena Shmakova ◽  
Mark Frost ◽  
Michael Batie ◽  
Niall S. Kenneth ◽  
Sonia Rocha
Keyword(s):  
Protein Expression ◽  
Cellular Response ◽  
Transcriptional Activity ◽  
Mrna Translation ◽  
Protein Translation ◽  
Signalling Pathways ◽  
Independent Function ◽  
Protein Levels ◽  
Associated Proteins ◽  
Core Components

PBRM1, a component of the chromatin remodeller SWI/SNF, is often deleted or mutated in human cancers, most prominently in renal cancers. Core components of the SWI/SNF complex have been shown to be important for the cellular response to hypoxia. Here, we investigated how PBRM1 controls HIF-1α activity. We found that PBRM1 is required for HIF-1α transcriptional activity and protein levels. Mechanistically, PBRM1 is important for HIF-1α mRNA translation, as absence of PBRM1 results in reduced actively translating HIF-1α mRNA. Interestingly, we found that PBRM1, but not BRG1, interacts with the m6A reader protein YTHDF2. HIF-1α mRNA is m6A-modified, bound by PBRM1 and YTHDF2. PBRM1 is necessary for YTHDF2 binding to HIF-1α mRNA and reduction of YTHDF2 results in reduced HIF-1α protein expression in cells. Our results identify a SWI/SNF-independent function for PBRM1, interacting with HIF-1α mRNA and the epitranscriptome machinery. Furthermore, our results suggest that the epitranscriptome-associated proteins play a role in the control of hypoxia signalling pathways.

scholarly journals Circular RNA circCSPP1 knockdown attenuates doxorubicin resistance and suppresses tumor progression of colorectal cancer via miR-944/FZD7 axis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lanlan Xi ◽  
Quanlin Liu ◽  
Wei Zhang ◽  
Linshan Luo ◽  
Jingfeng Song ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Tumor Growth ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Protein Levels ◽  
Cell Progression ◽  
Rna Immunoprecipitation ◽  
Induced Apoptosis

Abstract Background Circular RNAs (circRNAs) have been reported to play vital roles in colorectal cancer (CRC). However, only a few circRNAs have been experimentally validated and functionally described. In this research, we aimed to reveal the functional mechanism of circCSPP1 in CRC. Methods 36 DOX sensitive and 36 resistant CRC cases participated in this study. The expression of circCSPP1, miR-944 and FZD7 were detected by quantitative real time polymerase chain reaction (qRT-PCR) and the protein levels of FZD7, MRP1, P-gp and LRP were detected by western blot. Cell proliferation, migration, invasion, and apoptosis were assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay, transwell assay, or flow cytometry analysis, respectively. The interaction between miR-944 and circCSPP1 or frizzled-7 (FZD7) was predicted by Starbase 3.0 and verified by the dual luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down assay. Xenograft tumor assay was performed to examine the effect of circCSPP1 on tumor growth in vivo. Results The expression of circCSPP1 and FZD7 was upregulated while miR-944 expression was downregulated in doxorubicin (DOX)-resistant CRC tissues and cells. CircCSPP1 knockdown significantly downregulated enhanced doxorubicin sensitivity, suppressed proliferation, migration, invasion, and induced apoptosis in DOX-resistant CRC cells. Interestingly, we found that circCSPP1 directly downregulated miR-944 expression and miR-944 decreased FZD7 level through targeting to 3′ untranslated region (UTR) of FZD7. Furthermore, circCSPP1 mediated DOX-resistant CRC cell progression and doxorubicin sensitivity by regulating miR-944/FZD7 axis. Besides, circCSPP1 downregulation dramatically repressed CRC tumor growth in vivo. Conclusion Our data indicated that circCSPP1 knockdown inhibited DOX-resistant CRC cell growth and enhanced doxorubicin sensitivity by miR-944/FZD7 axis, providing a potential target for CRC therapy.

Sign in / Sign up

Export Citation Format

Share Document