scholarly journals Novel Proteomic changes in Yeast Mitochondria provide insights into mitochondrial functioning upon over-expression of human p53

2019 ◽  
Author(s):  
Archana Kumari Redhu ◽  
Jayadeva Paike Bhat
Keyword(s):  
Carbon Source ◽  
Warburg Effect ◽  
Pentose Phosphate ◽  
Yeast Cells ◽  
Yeast Mitochondria ◽  
Over Expression ◽  
Cycle Arrest ◽  
Glycolytic Activity ◽  
Sucrose Fermentation ◽  
Induced Apoptosis

AbstractCancer cells display enhanced glycolytic activity and impaired oxidative phosphorylation even in the presence of adequate oxygen (Warburg effect). Mitochondrial physiology is a promising hit target for anti-cancer therapy because of its key role in Warburg effect and activating apoptosis in mammalian as well as yeast cells. Over-expression of human p53 in S.cerevisiae leads to cell cycle arrest and apotosis. In the present work we show that how S.cerevisiae escapes from p53 induced apoptosis in fermentable carbon source, whereas in case of non-fermentable carbon source this phenomenon is not observed. To shed the light on this aspect we performed a quantitative proteomic analysis of yeast mitochondria isolated from the cells grown on sucrose (fermentation) and glycerol (respiration) with and without p53 over-expression. Through this approach, we identified a total dataset of 1120 proteins with 1% FDR, of which 239(133+106) proteins are differentially experssed in both conditions. Interestingly, we observed that after over-expression of p53 in sucrose grown yeast cells, a complete set of pentose phosphate pathway (PPP) enzymes is up-regulated in the mitochondria that leads to enhanced mitochondrial NADPH production and ROS quenching. Increased association of a hexose transporter (HXT6) and a hexokinase (HXK2) with the mitochondria of fermenting yeast cells upon over-expression of p53, may direct glucose towards PPP inside the mitochondria. In conclusion, our results provide the evidence that up-regulated PPP inside the mitochondria is a key to evade apoptosis by S.cerevisiae upon p53 over-expression.

Hyperpolarized [U-2H, U-13C]Glucose reports on glycolytic and pentose phosphate pathway activity in EL4 tumors and glycolytic activity in yeast cells

2014 ◽  
Vol 74 (6) ◽  
pp. 1543-1547 ◽  
Author(s):  
Kerstin N. Timm ◽  
Johannes Hartl ◽  
Markus A. Keller ◽  
De-En Hu ◽  
Mikko I. Kettunen ◽  
...  
Keyword(s):  
Pentose Phosphate Pathway ◽  
Pentose Phosphate ◽  
Yeast Cells ◽  
Pathway Activity ◽  
Glycolytic Activity

scholarly journals Monitoring yeast mitochondria with peroxiredoxin-based redox probes: the influence of oxygen and glucose availability

2017 ◽  
Vol 7 (2) ◽  
pp. 20160143 ◽  
Author(s):  
Daniel Pastor-Flores ◽  
Katja Becker ◽  
Tobias P. Dick
Keyword(s):  
Pentose Phosphate Pathway ◽  
Redox State ◽  
Pentose Phosphate ◽  
Yeast Cells ◽  
Mitochondrial Matrix ◽  
Yeast Mitochondria ◽  
Dominant Source ◽  
Significant Interest ◽  
Metabolic Conditions ◽  
Glucose Availability

Mitochondrially generated oxidants are believed to play important roles in both physiology and pathophysiology. Therefore, it is of significant interest to better understand the metabolic conditions leading to enhanced mitochondrial oxidant generation. Here, we investigate the influence of oxygen and glucose availability on the redox state of peroxiredoxin-based redox probes, expressed in the cytosol and mitochondrial matrix of yeast cells. We observe that the redox state of peroxiredoxin probes reflects the balance between dioxygen-dependent peroxide generation and glucose-dependent generation of reducing equivalents. The oxidative pentose phosphate pathway appears to be the dominant source of NADPH in the system under study.

p53-independent apoptosis induced by muscle differentiation stimuli in polyomavirus large T-expressing myoblasts

1999 ◽  
Vol 112 (14) ◽  
pp. 2397-2407
Author(s):  
V. Gottifredi ◽  
A. Peschiaroli ◽  
G.M. Fimia ◽  
R. Maione
Keyword(s):  
Muscle Differentiation ◽  
Growth Conditions ◽  
T Antigen ◽  
Dominant Negative ◽  
Dominant Negative Mutant ◽  
Independent Manner ◽  
Over Expression ◽  
Viral Oncogenes ◽  
Cycle Arrest ◽  
Induced Apoptosis

Abnormal proliferation signals, driven by cellular or viral oncogenes, can result in the induction of apoptosis under sub-optimal cell growth conditions. The tumor suppressor p53 plays a central role in mediating oncogene-induced apoptosis, therefore transformed cells lacking p53 are generally resistant to apoptosis-promoting treatments. In a previous work we have reported that the expression of polyomavirus large T antigen causes apoptosis in differentiating myoblasts and that this phenomenon is dependent on the onset of muscle differentiation in the absence of a correct cell cycle arrest. Here we report that polyomavirus large T increases the levels and activity of p53, but these alterations are not involved in the apoptotic mechanism. Apoptosis in polyomavirus large T-expressing myoblasts is not prevented by the expression of a p53 dominant-negative mutant nor it is increased by p53 over-expression. Moreover, forced differentiation induced through the over-expression of the muscle regulatory factor MyoD, leads to apoptosis without altering p53 function and, more significantly, even in a p53-null background. Our results indicate that apoptosis induced by the activation of muscle differentiation pathways in oncogene-expressing cells can occur in a p53-independent manner.

Synergistic Effect of α-Solanine and Cisplatin Induces Apoptosis and Enhances Cell Cycle Arrest in Human Hepatocellular Carcinoma Cells

2020 ◽  
Vol 19 (18) ◽  
pp. 2197-2210 ◽  
Author(s):  
Sherien M. El-Daly ◽  
Shaimaa A. Gouhar ◽  
Amira M. Gamal-Eldeen ◽  
Fatma F. Abdel Hamid ◽  
Magdi N. Ashour ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle ◽  
Synergistic Effect ◽  
Cell Cycle Arrest ◽  
Combination Treatment ◽  
Carcinoma Cells ◽  
Cell Growth Inhibition ◽  
Cycle Arrest ◽  
Induced Apoptosis ◽  
Human Hepatocellular Carcinoma Cells

Aim: The clinical application of cisplatin is limited by severe side effects associated with high applied doses. The synergistic effect of a combination treatment of a low dose of cisplatin with the natural alkaloid α-solanine on human hepatocellular carcinoma cells was evaluated. Methods: HepG2 cells were exposed to low doses of α-solanine and cisplatin, either independently or in combination. The efficiency of this treatment modality was evaluated by investigating cell growth inhibition, cell cycle arrest, and apoptosis enhancement. Results: α-solanine synergistically potentiated the effect of cisplatin on cell growth inhibition and significantly induced apoptosis. This synergistic effect was mediated by inducing cell cycle arrest at the G2/M phase, enhancing DNA fragmentation and increasing apoptosis through the activation of caspase 3/7 and/or elevating the expression of the death receptors DR4 and DR5. The induced apoptosis from this combination treatment was also mediated by reducing the expression of the anti-apoptotic mediators Bcl-2 and survivin, as well as by modulating the miR-21 expression. Conclusion: Our study provides strong evidence that a combination treatment of low doses of α-solanine and cisplatin exerts a synergistic anticancer effect and provides an effective treatment strategy against hepatocellular carcinoma.

scholarly journals Transcriptional Activation in Yeast Cells Lacking Transcription Factor IIA

Genetics ◽  
1999 ◽  
Vol 153 (4) ◽  
pp. 1573-1581 ◽  
Author(s):  
Susanna Chou ◽  
Sukalyan Chatterjee ◽  
Mark Lee ◽  
Kevin Struhl
Keyword(s):  
Transcription Factor ◽  
Transcriptional Activation ◽  
Large Subunit ◽  
Yeast Cells ◽  
Specific Cell ◽  
Wild Type ◽  
Activation Domains ◽  
Cycle Arrest ◽  
General Transcription Factor

Abstract The general transcription factor IIA (TFIIA) forms a complex with TFIID at the TATA promoter element, and it inhibits the function of several negative regulators of the TATA-binding protein (TBP) subunit of TFIID. Biochemical experiments suggest that TFIIA is important in the response to transcriptional activators because activation domains can interact with TFIIA, increase recruitment of TFIID and TFIIA to the promoter, and promote isomerization of the TFIID-TFIIA-TATA complex. Here, we describe a double-shut-off approach to deplete yeast cells of Toa1, the large subunit of TFIIA, to <1% of the wild-type level. Interestingly, such TFIIA-depleted cells are essentially unaffected for activation by heat shock factor, Ace1, and Gal4-VP16. However, depletion of TFIIA causes a general two- to threefold decrease of transcription from most yeast promoters and a specific cell-cycle arrest at the G2-M boundary. These results indicate that transcriptional activation in vivo can occur in the absence of TFIIA.

scholarly journals Silencing ZEB2 Induces Apoptosis and Reduces Viability in Glioblastoma Cell Lines

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 901
Author(s):  
Sahar Safaee ◽  
Masoumeh Fardi ◽  
Nima Hemmat ◽  
Neda Khosravi ◽  
Afshin Derakhshani ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Brain Tumor ◽  
Brain Tumors ◽  
Cell Lines ◽  
Scratch Test ◽  
Cycle Arrest ◽  
U373 Cell ◽  
Brain Tumor Cell ◽  
Induced Apoptosis ◽  
Glioma Tumors

Background: Glioma is an aggressive type of brain tumor that originated from neuroglia cells, accounts for about 80% of all malignant brain tumors. Glioma aggressiveness has been associated with extreme cell proliferation, invasion of malignant cells, and resistance to chemotherapies. Due to resistance to common therapies, glioma affected patients’ survival has not been remarkably improved. ZEB2 (SIP1) is a critical transcriptional regulator with various functions during embryonic development and wound healing that has abnormal expression in different malignancies, including brain tumors. ZEB2 overexpression in brain tumors is attributed to an unfavorable state of the malignancy. Therefore, we aimed to investigate some functions of ZEB2 in two different glioblastoma U87 and U373 cell lines. Methods: In this study, we investigated the effect of ZEB2 knocking down on the apoptosis, cell cycle, cytotoxicity, scratch test of the two malignant brain tumor cell lines U87 and U373. Besides, we investigated possible proteins and microRNA, SMAD2, SMAD5, and miR-214, which interact with ZEB2 via in situ analysis. Then we evaluated candidate gene expression after ZEB2-specific knocking down. Results: We found that ZEB2 suppression induced apoptosis in U87 and U373 cell lines. Besides, it had cytotoxic effects on both cell lines and reduced cell migration. Cell cycle analysis showed cell cycle arrest in G0/G1 and apoptosis induction in U87 and U373 cell lines receptively. Also, we have found that SAMAD2/5 expression was reduced after ZEB2-siRNA transfection and miR-214 upregulated after transfection. Conclusions: In line with previous investigations, our results indicated a critical oncogenic role for ZEB2 overexpression in brain glioma tumors. These properties make ZEB2 an essential molecule for further studies in the treatment of glioma cancer.

scholarly journals Overexpression of a Vesicle Trafficking Gene, OsRab7, Enhances Salt Tolerance in Rice

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaojue Peng ◽  
Xia Ding ◽  
Tianfang Chang ◽  
Zhoulong Wang ◽  
Rong Liu ◽  
...  
Keyword(s):  
Salt Tolerance ◽  
Transgenic Rice ◽  
Agricultural Production ◽  
Vesicle Trafficking ◽  
Yeast Cells ◽  
Root Tip ◽  
Over Expression ◽  
Crop Tolerance ◽  
Vacuolar Trafficking ◽  
Main Factor

High soils salinity is a main factor affecting agricultural production. Studying the function of salt-tolerance-related genes is essential to enhance crop tolerance to stress.Rab7is a small GTP-binding protein that is distributed widely among eukaryotes. Endocytic trafficking mediated byRab7plays an important role in animal and yeast cells, but the current understanding ofRab7in plants is still very limited. Herein, we isolated a vesicle trafficking gene,OsRab7, from rice. Transgenic rice over-expressingOsRab7exhibited enhanced seedling growth and increased proline content under salt-treated conditions. Moreover, an increased number of vesicles was observed in the root tip ofOsRab7transgenic rice. TheOsRab7over-expression plants showed enhanced tolerance to salt stress, suggesting that vacuolar trafficking is important for salt tolerance in plants.

Sign in / Sign up

Export Citation Format

Share Document