Medicine and Health Sciences Commons^™

Gasdermins In Apoptosis: New Players In An Old Game., Corey Rogers, Emad S. Alnemri

Department of Biochemistry and Molecular Biology Faculty Papers

Apoptosis is a form of programmed cell death (PCD) that plays critical physiological roles in removing superfluous or dangerous cell populations that are unneeded or threatening to the health of the host organism. Although the molecular pathways leading to activation of the apoptotic program have been extensively studied and characterized starting in the 1970s, new evidence suggests that members of the gasdermin superfamily are novel pore-forming proteins that augment apoptosis by permeabilizing the mitochondria and participate in the final stages of the apoptotic program by inducing secondary necrosis/pyroptosis. These findings may explain outstanding questions in the field such as why …

The Role Of Atf4 In Amyloid-Beta-Induced Neuronal Death., Gillian Petroff

Electronic Thesis and Dissertation Repository

Alzheimer’s disease (AD) is partially characterized by excessive accumulation of amyloid-b (Ab) in the brain. Ab oligomers have greater toxicity than Ab fibrils and induce neuronal stress. The Integrated Stress Response (ISR) is activated in response to cellular stress and increases expression of activating transcription factor 4 (ATF4) and its target genes. Prolonged activation has been shown to induce aberrant cell death, and increased markers of the ISR have been found in the brains of AD patients. However, the exact mechanism of amyloid-b-induced death is largely unknown. We aimed to determine if Ab-induced neuronal death occurs through ATF4-mediated upregulation of …

Caspases And Cancer: Connections Through Circular Dichroism Spectroscopy, Sarah M. Hethcox

Honors College Theses

While excessive cell death inevitably leads to negative effects, the endurance of damaged cells in the presence of death signals can be equally detrimental to health. Apoptosis, or programmed cell death, is a highly regulated process in which cues from within or from outside a cell can trigger an irreversible sequence of signals that carry out cell destruction known as the apoptotic cascade. A group of enzymes called caspases play a vital role in this cascade with some participating as initiators and others acting as effectors of protein cleavage and intracellular breakdown. Although it is normal for the activity of …

Role Of Atm In T Cell Dysfunction During Chronic Viral Infections, Juan Zhao

Electronic Theses and Dissertations

Hepatitis C virus (HCV) or human immunodeficiency virus (HIV) infection leads to a phenomenon of inflammaging, in which chronic infection or inflammation induces an immune aged phenotype with T cell dysfunction. Thus, HCV or HIV infection has been deemed as a model to study the mechanisms of T cell infammaging and viral persistence in humans. In this dissertation, T cell homeostasis, DNA damage and repair machineries were investigated in patients with chronic HCV or HIV infection at risk for inflammaging. We found a significant depletion in CD4 T cells, which was correlated with their apoptosis in chronically HCV/HIVinfected patients, compared …

Interaction Between The Bag1s Isoform And Hsp70 Mediates The Stability Of Anti-Apoptotic Proteins And The Survival Of Osteosarcoma Cells Expressing Oncogenic Myc., Victoria J. Gennaro, Helen Wedegaertner, Steven B. Mcmahon

Department of Biochemistry and Molecular Biology Faculty Papers

BACKGROUND: The oncoprotein MYC has the dual capacity to drive cell cycle progression or induce apoptosis, depending on the cellular context. BAG1 was previously identified as a transcriptional target of MYC that functions as a critical determinant of this cell fate decision. The BAG1 protein is expressed as multiple isoforms, each having an array of distinct biochemical functions; however, the specific effector function of BAG1 that directs MYC-dependent cell survival has not been defined.

METHODS: In our studies the human osteosarcoma line U2OS expressing a conditional MYC-ER allele was used to induce oncogenic levels of MYC. We interrogated MYC-driven survival …

Dynamic Light Scattering Optical Coherence Tomography To Probe Motion Of Subcellular Scatterers., Nico J J Arezza, Marjan Razani, Michael C Kolios

Medical Biophysics Publications

Optical coherence tomography (OCT) is used to provide anatomical information of biological systems but can also provide functional information by characterizing the motion of intracellular structures. Dynamic light scattering OCT was performed on intact, control MCF-7 breast cancer cells and cells either treated with paclitaxel to induce apoptosis or deprived of nutrients to induce oncosis. Autocorrelations (ACs) of the temporal fluctuations of OCT intensity signals demonstrate a significant decrease in decorrelation time after 24 h in both the paclitaxel-treated and nutrient-deprived cell groups but no significant differences between the two groups. The acquired ACs were then used as input for …

Vitamin E Δ-Tocotrienol Sensitizes Human Pancreatic Cancer Cells To Trail-Induced Apoptosis Through Proteasome-Mediated Down-Regulation Of C-Flip, Rony A. Francois, Anying Zhang, Kazim Husain, Chen Wang, Sean Hutchinson, Michael Kongnyuy, Surinder K. Batra, Domenico Coppola, Said M. Sebti, Mokenge P. Malafa

Journal Articles: Biochemistry & Molecular Biology

Background: Vitamin E δ-tocotrienol (VEDT), a vitamin E compound isolated from sources such as palm fruit and annatto beans, has been reported to have cancer chemopreventive and therapeutic effects.

Methods: We report a novel function of VEDT in augmenting tumor necrosis factor-related apoptosis-inducing ligand- (TRAIL-) induced apoptosis in pancreatic cancer cells. The effects of VEDT were shown by its ability to trigger caspase-8-dependent apoptosis in pancreatic cancer cells.

Results: When combined with TRAIL, VEDT significantly augmented TRAIL-induced apoptosis of pancreatic cancer cells. VEDT decreased cellular FLICE inhibitory protein (c-FLIP) levels without consistently modulating the expression of decoy death receptors 1, …

Using Peptide Mimetics To Probe Protein-Protein Interactions Significant In Cancers, Robert H. Whitaker

All ETDs from UAB

Protein-protein interactions are critical for cell life. One aspect of cellular regulation where such protein-protein interactions occur is in the highly regulated process of programmed cell death (or apoptosis). Apoptosis is critical for normal tissue homeostasis, differentiation, and if dysregulated is a driver of disease including cancers. At the center of apoptotic regulation is the BCL2 protein family whose intra-familial protein-protein interactions balance cell stress signaling either allowing the cell to survive or inducing mitochondrial cell death. These BCL2 protein interactions are accomplished through the BH3 motif. While unique to the BCL2 family, a similar motif, the reverse BH3, has …