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Molecular Biology

Apoptosis

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Articles 1 - 30 of 58

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Glutathione S-Transferase Class Mu Regulation Of Apoptosis Signal-Regulating Kinase 1 Protein During Vcd-Induced Ovotoxicity In Neonatal Rat Ovaries, Poulomi Bhattacharya, Jill A. Madden, Nivedita Sen, Patricia B. Hoyer, Aileen F. Keating Jul 2019

Glutathione S-Transferase Class Mu Regulation Of Apoptosis Signal-Regulating Kinase 1 Protein During Vcd-Induced Ovotoxicity In Neonatal Rat Ovaries, Poulomi Bhattacharya, Jill A. Madden, Nivedita Sen, Patricia B. Hoyer, Aileen F. Keating

Aileen Keating

4-vinylcyclohexene diepoxide (VCD) destroys ovarian primordial and small primary follicles via apoptosis. In mice, VCD exposure induces ovarian mRNA expression of glutathione S-transferase (GST) family members, including isoform mu (Gstm). Extra-ovarian GSTM negatively regulates pro-apoptotic apoptosis signal-related kinase 1 (ASK1) through protein complex formation, which dissociates during stress, thereby initiating ASK1-induced apoptosis. The present study investigated the ovarian response of Gstm mRNA and protein to VCD. Induction of Ask1 mRNA at VCD-induced follicle loss onset was determined. Ovarian GSTM:ASK1 protein complex formation was investigated and VCD exposure effects thereon evaluated. Phosphatidylinositol-3 kinase (PI3K) regulation of GSTM protein was also ...


Mechanisms Of Oriented Cell Division And Their Roles In Tissue Development, Evan Blake Dewey Apr 2019

Mechanisms Of Oriented Cell Division And Their Roles In Tissue Development, Evan Blake Dewey

Biology ETDs

Properly executed cell division is crucial to development, maintenance, and longevity of multicellular organisms. Defects in both symmetric and asymmetric divisions can lead to improper developmental patterning, as well as genomic instability, disruption of tissue homeostasis, and cancer. Our research focuses on how regulators orchestrate proper cell divisions. Mushroom Body Defect (Mud) is one such regulator, and here we describe how Mud is regulated via the Hippo signaling pathway kinase Warts (Wts), showing Wts phosphorylates Mud to enhance interaction with the polarity protein Partner of Inscuteable, promoting spindle orientation activity. We next focus on another regulator, Shortstop (Shot), describing a ...


The Caspase Cascade During Hibernation In The Golden-Mantled Ground Squirrel, Spermophilus Lateralis, Michael David Treat May 2018

The Caspase Cascade During Hibernation In The Golden-Mantled Ground Squirrel, Spermophilus Lateralis, Michael David Treat

UNLV Theses, Dissertations, Professional Papers, and Capstones

In several human pathologies like heart attack, stroke, neurodegenerative diseases, and autoimmune disorders, widespread cell death, or apoptosis, is a major cause of organ dysfunction and death. Hibernating golden-mantled ground squirrels, Spermophilus lateralis, experience numerous conditions during the winter that are known to be pro-apoptotic in other mammal systems (e.g. extreme hypothermia, ischemia and reperfusion, acidosis, increased reactive oxygen species, bone and muscle disuse). However, studies suggest that hibernators may invoke a protective phenotype to limit widespread cell damage and loss during the hibernation season. Could regulating apoptosis provide protection against the harmful conditions experienced during the hibernation season ...


The Effects Of Oxidative Stress On P75ntr Signaling In Dopaminergic Neurons, Cassandra Marie Escobedo Jan 2018

The Effects Of Oxidative Stress On P75ntr Signaling In Dopaminergic Neurons, Cassandra Marie Escobedo

Online Theses and Dissertations

The p75 neurotrophin receptor (p75NTR) is responsible for implementing cellular death during embryonic development and in response to cellular injury. The receptor has been recognized as a contributor of neurodegeneration in numerous pathological conditions. Cleavage of p75NTR by Tumor Necrosis Factor converting enzyme (TACE) and γ-secretase has been observed to be associated with an increase in neurodegeneration. In a previous study, p75NTR was discovered to become activated in sympathetic neurons in response to oxidative stress induced by 4-hydroxynonenal (HNE) in a ligand-independent mechanism. Furthermore, cleavage of the receptor was demonstrated to contribute to the death of sympathetic neurons following oxidative ...


The Molecular Basis Of Caspase-9 Inactivation By Pka And C-Abl Kinases, Banyuhay Paningbatan Serrano Jan 2018

The Molecular Basis Of Caspase-9 Inactivation By Pka And C-Abl Kinases, Banyuhay Paningbatan Serrano

Doctoral Dissertations

Caspases are the cysteine proteases that facilitate the fundamental pathway of programmed cell death or apoptosis. The activation and function of these powerful enzymes are tightly regulated to ensure the faithful execution of apoptosis and prevent untimely cell death. Many deadly human diseases such as cancer, neurodegeneration and autoimmune disorders have been associated with defective activation and faulty regulation of caspases. As such, caspases are considered as attractive drug targets, which when properly controlled, can lead to effective therapeutics for apoptosis-related diseases. Thus, comprehensive investigations of the structure, function and regulation of caspases are necessary to understand the complex mechanisms ...


Jnk Promotes Epithelial Cell Anoikis By Transcriptional And Post-Translational Regulation Of Bh3-Only Proteins, Nomeda Girnius, Roger J. Davis Nov 2017

Jnk Promotes Epithelial Cell Anoikis By Transcriptional And Post-Translational Regulation Of Bh3-Only Proteins, Nomeda Girnius, Roger J. Davis

UMass Metabolic Network Publications

Developmental morphogenesis, tissue injury, and oncogenic transformation can cause the detachment of epithelial cells. These cells are eliminated by a specialized form of apoptosis (anoikis). While the processes that contribute to this form of cell death have been studied, the underlying mechanisms remain unclear. Here, we tested the role of the cJUN NH2-terminal kinase (JNK) signaling pathway using murine models with compound JNK deficiency in mammary and kidney epithelial cells. These studies demonstrated that JNK is required for efficient anoikis in vitro and in vivo. Moreover, JNK-promoted anoikis required pro-apoptotic members of the BCL2 family of proteins. We show that ...


Differential Involvement Of The Microtubule Cytoskeleton In Insulin Receptor Substrate 1 (Irs-1) And Irs-2 Signaling To Akt Determines The Response To Microtubule Disruption In Breast Carcinoma Cells, Jose Mercado-Matos, Jennifer L. Clark, Andrew J. Piper, Jenny Janusis, Leslie M. Shaw May 2017

Differential Involvement Of The Microtubule Cytoskeleton In Insulin Receptor Substrate 1 (Irs-1) And Irs-2 Signaling To Akt Determines The Response To Microtubule Disruption In Breast Carcinoma Cells, Jose Mercado-Matos, Jennifer L. Clark, Andrew J. Piper, Jenny Janusis, Leslie M. Shaw

UMass Metabolic Network Publications

The insulin receptor substrate (IRS) proteins serve as essential signaling intermediates for the activation of PI3K by both the insulin-like growth factor 1 receptor (IGF-1R) and its close family member, the insulin receptor (IR). Although IRS-1 and IRS-2 share significant homology, they regulate distinct cellular responses downstream of these receptors and play divergent roles in breast cancer. To investigate the mechanism by which signaling through IRS-1 and IRS-2 results in differential outcomes, we assessed the involvement of the microtubule cytoskeleton in IRS-dependent signaling. Treatment with drugs that either stabilize or disrupt microtubules reveal that an intact microtubule cytoskeleton contributes to ...


Regulation Of The Drosophila Initiator Caspase Dronc Through Ubiquitylation, Hatem E. Kamber Kaya Jan 2017

Regulation Of The Drosophila Initiator Caspase Dronc Through Ubiquitylation, Hatem E. Kamber Kaya

GSBS Dissertations and Theses

Apoptosis is a programmed cell death mechanism that is evolutionary conserved from worms to humans. Apoptosis is mediated by initiator and effector caspases. The initiator caspases carry long pro-domains for their interaction with scaffolding proteins to form a cell-death platform, which is essential for their activation. Activated initiator caspases then cleave effector caspases that execute cell death through cleaving downstream targets. In addition to their apoptotic function, caspases also participate in events where caspase activity is not required for cell killing, but for regulating other functions, so-called non-apoptotic functions of caspases. The Drosophila initiator caspase Dronc, the ortholog of mammalian ...


Endoplasmic Reticulum Stress-Induced Hepatocellular Death Pathways Mediate Liver Injury And Fibrosis Via Stimulator Of Interferon Genes., Arvin Iracheta-Vellve, Jan Petrasek, Benedek Gyongyosi, Abhishek Satishchandran, Patrick Lowe, Karen Kodys, Donna Catalano, Charles D. Calenda, Evelyn A. Kurt-Jones, Kate A. Fitzgerald, Gyongyi Szabo Dec 2016

Endoplasmic Reticulum Stress-Induced Hepatocellular Death Pathways Mediate Liver Injury And Fibrosis Via Stimulator Of Interferon Genes., Arvin Iracheta-Vellve, Jan Petrasek, Benedek Gyongyosi, Abhishek Satishchandran, Patrick Lowe, Karen Kodys, Donna Catalano, Charles D. Calenda, Evelyn A. Kurt-Jones, Kate A. Fitzgerald, Gyongyi Szabo

Katherine A. Fitzgerald

Fibrosis, driven by inflammation, marks the transition from benign to progressive stages of chronic liver diseases. Although inflammation promotes fibrogenesis, it is not known whether other events, such as hepatocyte death, are required for the development of fibrosis. Interferon Regulatory Factor 3 (IRF3) regulates hepatocyte apoptosis and production of Type-I interferons (IFNs). In the liver, IRF3 is activated via Toll-like receptor 4 (TLR4) signaling or the ER adapter, Stimulator of Interferon Genes (STING). We hypothesized that IRF3-mediated hepatocyte death is an independent determinant of chemically-induced liver fibrogenesis. To test this, we performed acute or chronic carbontetrachloride (CCl4) administration to WT ...


Endoplasmic Reticulum Stress-Induced Hepatocellular Death Pathways Mediate Liver Injury And Fibrosis Via Stimulator Of Interferon Genes., Arvin Iracheta-Vellve, Jan Petrasek, Benedek Gyongyosi, Abhishek Satishchandran, Patrick Lowe, Karen Kodys, Donna Catalano, Charles D. Calenda, Evelyn A. Kurt-Jones, Kate A. Fitzgerald, Gyongyi Szabo Dec 2016

Endoplasmic Reticulum Stress-Induced Hepatocellular Death Pathways Mediate Liver Injury And Fibrosis Via Stimulator Of Interferon Genes., Arvin Iracheta-Vellve, Jan Petrasek, Benedek Gyongyosi, Abhishek Satishchandran, Patrick Lowe, Karen Kodys, Donna Catalano, Charles D. Calenda, Evelyn A. Kurt-Jones, Kate A. Fitzgerald, Gyongyi Szabo

Gyongyi Szabo

Fibrosis, driven by inflammation, marks the transition from benign to progressive stages of chronic liver diseases. Although inflammation promotes fibrogenesis, it is not known whether other events, such as hepatocyte death, are required for the development of fibrosis. Interferon Regulatory Factor 3 (IRF3) regulates hepatocyte apoptosis and production of Type-I interferons (IFNs). In the liver, IRF3 is activated via Toll-like receptor 4 (TLR4) signaling or the ER adapter, Stimulator of Interferon Genes (STING). We hypothesized that IRF3-mediated hepatocyte death is an independent determinant of chemically-induced liver fibrogenesis. To test this, we performed acute or chronic carbontetrachloride (CCl4) administration to WT ...


Tnf-Like Weak Inducer Of Apoptosis (Tweak) : Not So Weak After All., Joseph Dekward Mcmillan Iv Dec 2016

Tnf-Like Weak Inducer Of Apoptosis (Tweak) : Not So Weak After All., Joseph Dekward Mcmillan Iv

Electronic Theses and Dissertations

Background: Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a proinflammatory cytokine belonging to the TNF super family. TWEAK produces a variety of cellular responses through the binding to fibroblast growth factor inducible 14 (Fn14), a member of TNF receptor superfamily. Although Fn14 lacks a death domain, TWEAK has been found to induce apoptosis in some cell types by perturbing the activity of certain pathways such as TNF-receptor signaling. TWEAK is also known to regulate proliferation and differentiation of myogenic cells. We have previously reported that the TWEAK-Fn14 system causes skeletal muscle wasting both in vitro and ...


Endoplasmic Reticulum Stress-Induced Hepatocellular Death Pathways Mediate Liver Injury And Fibrosis Via Stimulator Of Interferon Genes., Arvin Iracheta-Vellve, Jan Petrasek, Benedek Gyongyosi, Abhishek Satishchandran, Patrick Lowe, Karen Kodys, Donna Catalano, Charles D. Calenda, Evelyn A. Kurt-Jones, Kate A. Fitzgerald, Gyongyi Szabo Nov 2016

Endoplasmic Reticulum Stress-Induced Hepatocellular Death Pathways Mediate Liver Injury And Fibrosis Via Stimulator Of Interferon Genes., Arvin Iracheta-Vellve, Jan Petrasek, Benedek Gyongyosi, Abhishek Satishchandran, Patrick Lowe, Karen Kodys, Donna Catalano, Charles D. Calenda, Evelyn A. Kurt-Jones, Kate A. Fitzgerald, Gyongyi Szabo

GSBS Student Publications

Fibrosis, driven by inflammation, marks the transition from benign to progressive stages of chronic liver diseases. Although inflammation promotes fibrogenesis, it is not known whether other events, such as hepatocyte death, are required for the development of fibrosis. Interferon Regulatory Factor 3 (IRF3) regulates hepatocyte apoptosis and production of Type-I interferons (IFNs). In the liver, IRF3 is activated via Toll-like receptor 4 (TLR4) signaling or the ER adapter, Stimulator of Interferon Genes (STING). We hypothesized that IRF3-mediated hepatocyte death is an independent determinant of chemically-induced liver fibrogenesis. To test this, we performed acute or chronic carbontetrachloride (CCl4) administration to WT ...


The Beneficial Role Of Extracellular Reactive Oxygen Species In Apoptosis-Induced Compensatory Proliferation, Neha Diwanji, Andreas Bergmann Aug 2016

The Beneficial Role Of Extracellular Reactive Oxygen Species In Apoptosis-Induced Compensatory Proliferation, Neha Diwanji, Andreas Bergmann

Molecular, Cell and Cancer Biology Publications

Apoptosis-induced proliferation (AiP) maintains tissue homeostasis following massive stress-induced cell death. During this phenomenon, dying cells induce proliferation of the surviving cells to compensate for the tissue loss, and thus restore organ size. Along with wound healing and tissue regeneration, AiP also contributes to tumor repopulation following radiation or chemotherapy. There are several models of AiP. Using an "undead" AiP model that causes hyperplastic overgrowth of Drosophila epithelial tissue, we recently demonstrated that extracellular reactive oxygen species (eROS) are produced by undead epithelial cells, and are necessary for inducing AiP and overgrowth. Furthermore, hemocytes, the Drosophila blood cells, are seen ...


Investigation Of Novel Functions For Dna Damage Response And Repair Proteins In Escherichia Coli And Humans, Benjamin A. Hilton May 2016

Investigation Of Novel Functions For Dna Damage Response And Repair Proteins In Escherichia Coli And Humans, Benjamin A. Hilton

Electronic Theses and Dissertations

Endogenous and exogenous agents that can damage DNA are a constant threat to genome stability in all living cells. In response, cells have evolved an array of mechanisms to repair DNA damage or to eliminate the cells damaged beyond repair. One of these mechanisms is nucleotide excision repair (NER) which is the major repair pathway responsible for removing a wide variety of bulky DNA lesions. Deficiency, or mutation, in one or several of the NER repair proteins is responsible for many diseases, including cancer. Prokaryotic NER involves only three proteins to recognize and incise a damaged site, while eukaryotic NER ...


Modulation Of Cell Death Signaling And Cell Proliferation By The Interaction Of Homoserine Lactones And Paraoxonase 2., Aaron Mackallan Neely May 2016

Modulation Of Cell Death Signaling And Cell Proliferation By The Interaction Of Homoserine Lactones And Paraoxonase 2., Aaron Mackallan Neely

Electronic Theses and Dissertations

Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule that functions to facilitate bacteria-bacteria communication. C12 has also been reported to affect many aspects of human host cell physiology, including evoking cell death in various types of cells. However, the signaling pathway(s) leading to C12-triggerred cell death remains unclear. To clarify cell death signaling induced by C12, we examined mouse embryonic fibroblasts (MEFs) deficient in one or more caspases. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in cells, probably through the direct induction of mitochondrial membrane permeabilization. Previous ...


Characterization And Target Identification Of Ak301: A Novel Mitotic Arrest Agent, Michael J. Bond, Avijeet S. Chopra, Marina Bleiler, Michelle Yeagley, Eric Scocchera Apr 2016

Characterization And Target Identification Of Ak301: A Novel Mitotic Arrest Agent, Michael J. Bond, Avijeet S. Chopra, Marina Bleiler, Michelle Yeagley, Eric Scocchera

University Scholar Projects

The Giardina Laboratory has recently identified AK301 as a novel mitotic arrest agent. This work aimed to characterize the arrest state induced by AK301 (EC50 ~ 150nM) and identify the cellar targets responsible for the arrest. It was found that AK301 arrest is readily reversible upon withdrawal of AK301. Cells that slip from mitosis after removal of AK301 are sensitized to apoptosis. This was found to be unique for AK301 when compared to other mitotic arrest agents like colchicine, vincristine, and BI2536. Arrested cells were found to have increased ATM activity as well as an upregulation of p53 and several ...


Non-Thermal Atmospheric Plasma Induces Ros-Independent Cell Death In U373mg Glioma Cells And Augments The Cytotoxicity Of Temozolomide, Gillian Conway, Alan Casey, Vladimir Milosavljevic, Yupeng Liu, Orla L. Howe, Patrick Cullen, James Curtin Feb 2016

Non-Thermal Atmospheric Plasma Induces Ros-Independent Cell Death In U373mg Glioma Cells And Augments The Cytotoxicity Of Temozolomide, Gillian Conway, Alan Casey, Vladimir Milosavljevic, Yupeng Liu, Orla L. Howe, Patrick Cullen, James Curtin

Articles

Non-thermal atmospheric plasma (NTAP) is an ionised gas produced under high voltage that can generate short-lived chemically active species and induce a cytotoxic insult in cancer cells. Cell-specific resistance to NTAP-mediated cytotoxicity has been reported in the literature. The aim of this study was to determine whether resistance against NTAP could be overcome using the human glioma cell line U373MG.

Methods:

Non-thermal atmospheric plasma was generated using a Dielectric Barrier Device (DBD) system with a maximum voltage output of 120 kV at 50 Hz. The viability of U373MG GBM cells and HeLa cervical carcinoma cells was determined using morphology, flow ...


Mir494 Reduces Renal Cancer Cell Survival Coinciding With Increased Lipid Droplets And Mitochondrial Changes, Punashi Dutta, Edward Haller, Arielle Sharp, Meera Nanjundan Jan 2016

Mir494 Reduces Renal Cancer Cell Survival Coinciding With Increased Lipid Droplets And Mitochondrial Changes, Punashi Dutta, Edward Haller, Arielle Sharp, Meera Nanjundan

Cell Biology, Microbiology, and Molecular Biology Faculty Publications

Background: miRNAs can regulate cellular survival in various cancer cell types. Recent evidence implicates the formation of lipid droplets as a hallmark event during apoptotic cell death response. It is presently unknown whether MIR494, located at 14q32 which is deleted in renal cancers, reduces cell survival in renal cancer cells and if this process is accompanied by changes in the number of lipid droplets.

Methods: 769-P renal carcinoma cells were utilized for this study. Control or MIR494 mimic was expressed in these cells following which cell viability (via crystal violet) and apoptotic cell numbers (via Annexin V/PI staining) were ...


Direct Regulation Of Apoptosis By Linear Ubiqutin Chain Assembly Complex (Lubac) And Feedback Regulation Of Lubac Function By Caspases, Donghyun Joo Aug 2015

Direct Regulation Of Apoptosis By Linear Ubiqutin Chain Assembly Complex (Lubac) And Feedback Regulation Of Lubac Function By Caspases, Donghyun Joo

UT GSBS Dissertations and Theses (Open Access)

Tumor Necrosis Factor-alpha (TNF-α) is a cytokine that plays a role in various cellular processes such as proliferation, differentiation (mainly through NF-κB signaling) and death (via apoptosis signaling). Recently, linear ubiquitination by LUBAC (linear ubiquitin chain assembly complex) was reported to have a regulatory function in TNF-α mediated NF-κB activation. Although LUBAC is suggested to control not only NF-kB signaling but also the apoptosis pathway, the precise mechanism of apoptosis regulation remains unknown. Moreover, NF-κB and apoptosis pathways have opposed but fundamental functions for various cellular processes. Although these two pathways actively interplay to balance the death and survival, the ...


Chronic Inflammation As A Result Of Hepatitis C Virus Infection: A Review Of The Literature, Samantha L. Lane May 2015

Chronic Inflammation As A Result Of Hepatitis C Virus Infection: A Review Of The Literature, Samantha L. Lane

DePaul Discoveries

Approximately 170 million people are infected with Hepatitis C virus (HCV) worldwide5,6. It is estimated that roughly 80% of those infected suffer from persistent infection with the virus; this persistence of infection is progressive, and over time can lead to fibrosis, cirrhosis, and hepatocellular carcinoma7. Chronic inflammation and apoptotic deregulation are both hallmarks of chronic HCV infection, and many molecular pathways are initiated in both the innate and adaptive immune responses during infection with this viral pathogen. The aim of this review was to survey some of the major molecular mechanisms responsible for the induction of chronic ...


The Epigenetic Regulators Atrx And Ctcf Are Required For Mouse Neuroprogenitor Cell Survival And Brain Development, Lauren Ashley Watson Apr 2015

The Epigenetic Regulators Atrx And Ctcf Are Required For Mouse Neuroprogenitor Cell Survival And Brain Development, Lauren Ashley Watson

Electronic Thesis and Dissertation Repository

Emerging evidence implicates the regulation of higher-order chromatin structure in brain development, maturation, and function. Human mutations in two important regulators of chromatin structure, ATRX and CTCF, cause microcephaly and intellectual disability and have been identified in several cancers, suggesting an important role for these proteins in the developing brain and to suppress tumorigenesis. This thesis demonstrates that chromatin structure is critical to the differentiation and survival of neural progenitor cells, and explores the mechanisms of ATRX and CTCF function in brain development. The first chapter identifies that Atrx deficiency induces replicative DNA damage at telomeres and pericentromeric heterochromatin, and ...


Stat6 Mediates Interleukin-4 Growth Inhibition In Human Breast Cancer Cells, Jennifer L. Gooch, B. Christy, D. Yee Mar 2015

Stat6 Mediates Interleukin-4 Growth Inhibition In Human Breast Cancer Cells, Jennifer L. Gooch, B. Christy, D. Yee

Jennifer L. Gooch

In addition to acting as a hematopoietic growth factor, interleukin-4 (IL-4) inhibits growth of some transformed cells in vitro and in vivo. In this study, we show that insulin receptor substrate (IRS)-1, IRS-2, and signal transducer and activator of transcription 6 (STAT6) are phosphorylated following IL-4 treatment in MCF-7 breast cancer cells. STAT6 DNA binding is enhanced by IL-4 treatment. STAT6 activation occurs even after IRS-1 depletion, suggesting the two pathways are independent. To examine the role of STAT6 in IL-4-mediated growth inhibition and apoptosis, a full-length STAT6 cDNA was transfected into MCF-7 cells. Transient overexpression of STAT6 resulted ...


Cross-Talk Between The Tumor Suppressors Par-4 And P53, Tripti Shrestha Bhattarai Jan 2015

Cross-Talk Between The Tumor Suppressors Par-4 And P53, Tripti Shrestha Bhattarai

Theses and Dissertations--Toxicology and Cancer Biology

This work describes the fascinating interplay between two tumor suppressors Prostate apoptosis response-4 (Par-4) and p53. The guardian of the genome, p53, is frequently mutated in human cancers, and may contribute to therapeutic resistance. However, p53 is intact and functional in normal tissues, and we observed that specific activation of p53 in normal fibroblasts could induce apoptosis selectively in p53-deficient cancer cells. This paracrine apoptotic effect was executed by Par-4 secreted in response to p53 activation. Accordingly, activation of p53 in wild-type mice, but not in p53-/- or Par-4-/- mice, caused systemic elevation of Par-4 that induced apoptosis of p53-deficient ...


A Protective Role Of Autophagy In A Drosophila Model Of Friedreich's Ataxia (Frda), Luan Wang Jan 2015

A Protective Role Of Autophagy In A Drosophila Model Of Friedreich's Ataxia (Frda), Luan Wang

Wayne State University Dissertations

Friedreich’s ataxia (FRDA) is an inherited autosomal recessive neurodegenerative disease. It affects 1 in every 50,000 people in central Europe and North America. FRDA is caused by deficiency of Frataxin, an essential mitochondrial iron chaperone protein, and the associated oxidative stress damages. Autophagy, a housekeeping process responsible for the bulk degradation and turnover of long half-life proteins and organelles, is featured by the formation of double-membrane vacuoles and lysosomal degradation. Previous researches indicate that Danon’s disease, the inherited neural disorder disease that shares similar symptoms with FRDA, is due to the malfunction of autophagy. Based on this ...


The Role Of The Ku70 Vwa Domain In The Response To Dna Double Strand Breaks, Victoria L. Fell Nov 2014

The Role Of The Ku70 Vwa Domain In The Response To Dna Double Strand Breaks, Victoria L. Fell

Electronic Thesis and Dissertation Repository

Ku is an abundant, highly conserved DNA binding protein found in both prokaryotes and eukaryotes that plays essential roles in the maintenance of genome integrity. In eukaryotes, Ku is a heterodimer comprised of two subunits, Ku70 and Ku80, and is best characterized for its central role as the initial DNA end binding factor in the “classical” non-homologous end joining (C-NHEJ) pathway, the main DNA double-strand break (DSB) repair pathway in mammals. At the break, Ku directly and indirectly interacts with several C-NHEJ factors and processing enzymes, serving as the scaffold for the entire DNA repair complex. In this work we ...


Nuclear Pore Component Nup98 Is A Potential Tumor Suppressor And Regulates Posttranscriptional Expression Of Select P53 Target Genes, Stephan Singer, Ruiying Zhao, Anthony M. Barsotti, Anette Ouwehand, Mina Fazollahi, Elias Coutavas, Kai Breuhahn, Olaf Neumann, Thomas Longerich, Tobias Pusterla, Maureen A. Powers, Keith M. Giles, Peter J. Leedman, Jochen Hess, David Grunwald, Harmen J. Bussemaker, Robert H. Singer, Peter Schirmacher, Carol Prives Nov 2014

Nuclear Pore Component Nup98 Is A Potential Tumor Suppressor And Regulates Posttranscriptional Expression Of Select P53 Target Genes, Stephan Singer, Ruiying Zhao, Anthony M. Barsotti, Anette Ouwehand, Mina Fazollahi, Elias Coutavas, Kai Breuhahn, Olaf Neumann, Thomas Longerich, Tobias Pusterla, Maureen A. Powers, Keith M. Giles, Peter J. Leedman, Jochen Hess, David Grunwald, Harmen J. Bussemaker, Robert H. Singer, Peter Schirmacher, Carol Prives

David Grünwald

The p53 tumor suppressor utilizes multiple mechanisms to selectively regulate its myriad target genes, which in turn mediate diverse cellular processes. Here, using conventional and single-molecule mRNA analyses, we demonstrate that the nucleoporin Nup98 is required for full expression of p21, a key effector of the p53 pathway, but not several other p53 target genes. Nup98 regulates p21 mRNA levels by a posttranscriptional mechanism in which a complex containing Nup98 and the p21 mRNA 3'UTR protects p21 mRNA from degradation by the exosome. An in silico approach revealed another p53 target (14-3-3sigma) to be similarly regulated by Nup98. The ...


Elucidating The Signalling Pathway Of Mer Tyrosine Kinase Receptor In Efferocytosis, Ekenedelichukwu Azu Aug 2014

Elucidating The Signalling Pathway Of Mer Tyrosine Kinase Receptor In Efferocytosis, Ekenedelichukwu Azu

Electronic Thesis and Dissertation Repository

Efferocytosis is the clearance of apoptotic cells and is necessary for homeostasis. Mer Tyrosine Kinase (MerTK) is a crucial efferocytic receptor whose loss is associated with chronic inflammatory diseases and autoimmunity. While previous studies have shown that MerTK mediates efferocytosis through a unique mechanism that requires integrins, MerTK signalling pathway remains unknown. Given this unusual internalization mechanism, I hypothesized that MerTK signals and engages integrins through a novel signalling pathway different from that used by other phagocytic receptors. Therefore, this study aimed to identify the signalling pathways activated by MerTK, utilizing conventional cell biology and pharmacological approaches.

I found that ...


Calcium-Mediated Pore Expansion And Cell Death Following Nanoelectroporation, Olga N. Pakhomova, Betsy Gregory, Iurii Semenov, Andrei G. Pakhomov Jan 2014

Calcium-Mediated Pore Expansion And Cell Death Following Nanoelectroporation, Olga N. Pakhomova, Betsy Gregory, Iurii Semenov, Andrei G. Pakhomov

Bioelectrics Publications

Opening of long-lived pores in the cell membrane is the principal primary effect of intense, nanosecond pulsed electric field (nsPEF). Here we demonstrate that the evolution of pores, cell survival, the time and the mode of cell death (necrotic or apoptotic) are determined by the level of external Ca2+ after nsPEF. We also introduce a novel, minimally disruptive technique for nsEP exposure of adherent cells on indium tin oxide (ITO)-coated glass coverslips, which does not require cell detachment and enables fast exchanges of bath media. Increasing the Ca2+ level from the nominal 2–5 μM to 2 ...


Inhibition Of Lung Carcinogenesis By Polymethoxyflavones, Noppawat Charoensinphon Sep 2013

Inhibition Of Lung Carcinogenesis By Polymethoxyflavones, Noppawat Charoensinphon

Open Access Dissertations

Lung cancer is the leading cause of cancer-related death worldwide. Exclusively found in citrus peels, the inhibitory effects of polymethoxyflavones (PMFs) on 3 human non-small cell lung cancer cells have been investigated. Results showed that monodemethylated PMFs at 5-position potently inhibited lung cancer cells than those of their permethoxylated counterparts. The inhibition of cancer cells caused by monodemethylated PMFs was associated with both extensive cell cycle arrest and apoptosis as a result of modulation of key oncogenic signaling proteins. Treatment with different bioactive compounds in combination may enhance inhibitory effects on lung cancer due to their synergistic interaction among these ...


Glutathione S-Transferase Class Mu Regulation Of Apoptosis Signal-Regulating Kinase 1 Protein During Vcd-Induced Ovotoxicity In Neonatal Rat Ovaries, Poulomi Bhattacharya, Jill A. Madden, Nivedita Sen, Patricia B. Hoyer, Aileen F. Keating Feb 2013

Glutathione S-Transferase Class Mu Regulation Of Apoptosis Signal-Regulating Kinase 1 Protein During Vcd-Induced Ovotoxicity In Neonatal Rat Ovaries, Poulomi Bhattacharya, Jill A. Madden, Nivedita Sen, Patricia B. Hoyer, Aileen F. Keating

Animal Science Publications

4-vinylcyclohexene diepoxide (VCD) destroys ovarian primordial and small primary follicles via apoptosis. In mice, VCD exposure induces ovarian mRNA expression of glutathione S-transferase (GST) family members, including isoform mu (Gstm). Extra-ovarian GSTM negatively regulates pro-apoptotic apoptosis signal-related kinase 1 (ASK1) through protein complex formation, which dissociates during stress, thereby initiating ASK1-induced apoptosis. The present study investigated the ovarian response of Gstm mRNA and protein to VCD. Induction of Ask1 mRNA at VCD-induced follicle loss onset was determined. Ovarian GSTM:ASK1 protein complex formation was investigated and VCD exposure effects thereon evaluated. Phosphatidylinositol-3 kinase (PI3K) regulation of GSTM protein was also ...