Cell Biology Commons^™

P53 Phosphomimetics Preserve Transient Secondary Structure But Reduce Binding To Mdm2 And Mdmx, Robin Levy, Emily Gregory, Wade Borcherds, Gary W. Daughdrill

Molecular Biosciences Faculty Publications

The disordered p53 transactivation domain (p53TAD) contains specific levels of transient helical secondary structure that are necessary for its binding to the negative regulators, mouse double minute 2 (Mdm2) and MdmX. The interactions of p53 with Mdm2 and MdmX are also modulated by posttranslational modifications (PTMs) of p53TAD including phosphorylation at S15, T18 and S20 that inhibits p53-Mdm2 binding. It is unclear whether the levels of transient secondary structure in p53TAD are changed by phosphorylation or other PTMs. We used phosphomimetic mutants to determine if adding a negative charge at positions 15 and 18 has any effect on the transient …

Identification Of Proteins Interacting With Zebrafish Miro Orthologs In The Yeast Two-Hybrid System, Yiran Tao

Honors Program Theses

The motility of mitochondria is required for providing energy and maintaining basic cellular functions in neurons. Mitochondrial Rho GTPase (Miro) is an essential component of the mitochondrial trafficking machinery, a protein complex that anchors mitochondria to the microtubule motor protein for long-distance transport. As a protein localizing to the mitochondrial outer membrane, Miro regulates the morphology and the motility of mitochondria. Upon mitochondrial depolarization, the PINK1/Parkin pathway is activated to arrest mitochondrial movement by targeting Miro for phosphorylation and ubiquitination in a calcium-sensitive manner. However, it remains unclear what effects the PINK1-dependent phosphorylation has on the structure and binding properties …

The Otud5–Ubr5 Complex Regulates Fact-Mediated Transcription At Damaged Chromatin, Angelo De Vivo, University Of South Florida, Jose Yegres, Jeonghyeon Kim, Sylvia Emly, Younghoon Kee

Molecular Biosciences Faculty Publications

Timely stalling and resumption of RNA polymerases at damaged chromatin are actively regulated processes. Prior work showed an importance of FACT histone chaperone in such process. Here we provide a new role of OTUD5 deubiquitinase in the FACT-dependent process. Through a DUB RNAi screen, we found OTUD5 as a specific stabilizer of the UBR5 E3 ligase. OTUD5 localizes to DNA double strand breaks (DSBs), interacts with UBR5 and represses the RNA Pol II elongation and RNA synthesis. OTUD5 co-localizes and interacts with the FACT component SPT16 and antagonizes the histone H2A deposition at DSB lesions. OTUD5 interacts with UBR5 and …

Effects Of Pag1 On Src-Family Kinase Trafficking In Neuroblastoma Cells, Makenzie E. Mayfield

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The receptor tyrosine kinases (RTKs) are known to help regulate cell behaviors including differentiation, proliferation and migration during embryonic development of the neural crest. RTKs are believed to initiate signaling cascades in response to extracellular cues in part by controlling localization of Src-family kinases (SFKs). The scaffolding protein PAG1 binds SFKs and is believed to influence SFK activity and location within the cell by promoting interaction of SFKs with regulatory proteins and by drawing SFKs into different components of the endocytic pathway. By targeting the PAG1 gene in SH-SY5Y neuroblastoma cells with CRISPR/Cas9 plasmids, we created PAG1-mutant cell-lines in which …

Nanosecond Pulsed Electric Signals Can Affect Electrostatic Environment Of Protiens Below The Threshold Of Conformational Effects: The Case Study Of Sod1 With A Molecular Simulation Study, Elena Della Valle, Paolo Marracino, Olga Pakhomova, Micaela Liberti, Francesca Apollonio

Bioelectrics Publications

Electric fields can be a powerful tool to interact with enzymes or proteins, with an intriguing perspective to allow protein manipulation. Recently, researchers have focused the interest on intracellular enzyme modifications triggered by the application of nanosecond pulsed electric fields. These findings were also supported by theoretical predictions from molecular dynamics simulations focussing on significant variations in protein secondary structures. In this work, a theoretical study utilizing molecular dynamics simulations is proposed to explore effects of electric fields of high intensity and very short nanosecond duration applied to the superoxide dismutase (Cu/Zn-SOD or SOD-1), an important enzyme involved in the …

Intratumoral Delivery Of Plasmid Il12 Via Electroporation Leads To Regression Of Injected And Noninjected Tumors In Merkel Cell Carcinoma, Shailender Bhatia, Natalie V. Longino, Natalie J. Miller, Rima Kulikauskas, Jayasri G. Iyer, Dafina Ibrani, Astrid Blom, David R. Byrd, Upendra Parvathaneni, Christopher Twitty, Jean S. Campbell, Mai H. Le, Sharron Gargosky, Robert H. Pierce, Richard Heller, Adil Daud, Paul Nghiem

Bioelectrics Publications

Purpose: Interleukin-12 (IL12) promotes adaptive type I immunity and has demonstrated antitumor efficacy, but systemic administration leads to severe adverse events (AE), including death. This pilot trial investigated safety, efficacy, and immunologic activity of intratumoral delivery of IL12 plasmid DNA (tavo) via in vivo electroporation (i.t.-tavo-EP) in patients with Merkel cell carcinoma (MCC), an aggressive virus-associated skin cancer.

Experimental Design: Fifteen patients with MCC with superficial injectable tumor(s) received i.t.-tavo-EP on days 1, 5, and 8 of each cycle. Patients with locoregional MCC (cohort A, N = 3) received one cycle before definitive surgery in week 4. …

Nanosecond Pulsed Electric Fields Induce Endoplasmic Reticulum Stress Accompanied By Immunogenic Cell Death In Murine Models Of Lymphoma And Colorectal Cancer, Alessandra Rossi, Olga N. Pakhomova, Peter A. Mollica, Maura Casciola, Uma Mangalanathan, Andrei G. Pakhomov, Claudia Muratori

Bioelectrics Publications

Depending on the initiating stimulus, cancer cell death can be immunogenic or non-immunogenic. Inducers of immunogenic cell death (ICD) rely on endoplasmic reticulum (ER) stress for the trafficking of danger signals such as calreticulin (CRT) and ATP. We found that nanosecond pulsed electric fields (nsPEF), an emerging new modality for tumor ablation, cause the activation of the ER-resident stress sensor PERK in both CT-26 colon carcinoma and EL-4 lymphoma cells. PERK activation correlates with sustained CRT exposure on the cell plasma membrane and apoptosis induction in both nsPEF-treated cell lines. Our results show that, in CT-26 cells, the activity of …

Regorafenib Enhances Lethality Of Sildenafil And Curcumin In Colorectal Cancer Cells, Kervin Benjamin Owusu

Theses and Dissertations

In the United States, more than 130,000 people will be diagnosed with colorectal cancer (CRC) each year and an estimated 50,000 people will die from the disease. Standard of care (SOC) therapies for CRC combine multiple cytotoxic chemotherapeutic drugs. These combinations have varying degrees of effectiveness and can often result in significant patient morbidity. For second recurrence patients, the multi-kinase inhibitor, regorafenib, is an approved agent, but is often poorly tolerated at current doses. In the current study, we propose to develop therapeutic regime of combining agents with modest toxicity profiles: curcumin and sildenafil with regorafenib. Using clinically achievable enterohepatic …

The Dna Dependent Protein Kinase Catalytic Subunit Maintains Genomic Stability, Brandon Lee Sklavanitis

Graduate Research Theses & Dissertations

GBM is the most common CNS derived malignancy diagnosed each year. The median survival time to date is between 14.6 to 16.7 months for patients suffering from the disease. Clinical trials and research has yet to yield a breakthrough treatment. The invasive nature of GBM to surrounding tissue typically poses a challenge for complete surgical resection of the tumor, and radiotherapy remains a predominant treatment modality. The NHEJ pathway is main repair pathway responsible for repairing lethal radiation damage. As a result, this study used the CRISPR-Cas9 system to genetically engineer two GBM cell lines lacking expression of an essential …

Comparative Tumorigenic Amino Acid Starvation And Integrated Stress Responses In Epithelial Vs. Mesenchymal Hcc Cells With Asct2 Or Lat1 Transporter Knockouts, Stephanie Lois Cooper Woodin

Graduate Research Theses & Dissertations

The previously established roles of the amino acid glutamine have recently been expanded to include not only protein and nucleotide synthesis, as well as contributing significantly to energy production via mitochondrial hydrolysis of glutamine to glutamate, but also the role of this molecule in the reductive carboxylation of α-ketoglutarate resulting in carbon atoms used in cell membrane biosynthesis. Additionally, glutamine participates in maintaining glutathione homeostasis as well as regulation of anabolic signaling. Given its central role in anabolic processes, glutamine is preferentially transported into human cancer cells at a significant rate as compared to normal cells. This distinction has prompted …

Effect Of Oil Palm Phenolics (Opp) On Pancreatic Cancer Cell Lines, Inaam Abdul Karim

Wayne State University Theses

Pancreatic cancer (paca) is currently the fifth causes of cancer-related deaths in the United States. It’s an aggressive form of cancer with very low survival rates because of delayed diagnosis and limited treatment options. Gemcitabine is the chemotherapy drug that provides minimal benefits along with many side effects. The aim of this study was to examine the in vitro effects of oil palm phenolics (OPP) fraction-5, the water-soluble component of palm oil, in human pancreatic cancer cell models. Two pancreatic cancer cell lines (Panc-1 and BxPC-3) were categorized into control and treatment groups. The control group received cell culture media …

The Role Of Rock Signaling On Salivary Gland Organoid Formation, Matthew Koslow

Legacy Theses & Dissertations (2009 - 2024)

Salivary glands are crucial organs that are responsible for secreting saliva which is important for the breakdown of carbohydrates, providing lubrication of the mouth, and maintenance of oral health. Patients diagnosed with Sjögren's Syndrome or receiving treatment for head and neck cancer, can permanently lose salivary gland function, which is referred to as salivary hypofunction. As a result, these patients develop Xerostomia, or the feeling of dry mouth, and suffer from an overall decreased quality of life. To combat the negative effects of salivary hypofunction, stem cell therapy is an attractive option, as implantation of specific cell populations can rescue …

Of Donuts And Promo : In Silico Approaches To Identification Of Transcriptional Regulators Of Salivary Acinar Differentiation, Connor Cillian Duffy

Legacy Theses & Dissertations (2009 - 2024)

The salivary gland is an organ often taken for granted by most people. However, its proper function is essential for several everyday activities, such as speaking, swallowing, and tasting. As such, impaired salivary gland function, such as that caused by Sjögren’s Syndrome or radiotherapy for head and neck cancers, can lead to a significantly reduced quality of life. The cells that produce saliva in salivary glands are known as acinar cells, which arise from proacinar cells generated during embryonic development. As such, in studying the promoter regions of proacinar and acinar genes, it may be possible to identify common transcription …

Mechanisms Of Trinucleotide Repeat Instability During Dna Synthesis, Kara Y. Chan

Theses and Dissertations--Toxicology and Cancer Biology

Genomic instability, in the form of gene mutations, insertions/deletions, and gene amplifications, is one of the hallmarks in many types of cancers and other inheritable genetic disorders. Trinucleotide repeat (TNR) disorders, such as Huntington’s disease (HD) and Myotonic dystrophy (DM) can be inherited and repeats may be extended through subsequent generations. However, it is not clear how the CAG repeats expand through generations in HD. Two possible repeat expansion mechanisms include: 1) polymerase mediated repeat extension; 2) persistent TNR hairpin structure formation persisting in the genome resulting in expansion after subsequent cell division. Recent in vitro studies suggested that a …

Vitamin D Receptor Gene Polymorphisms Knowledge And Breast Cancer In Texas, Ejike Roland Egwuekwe

Walden Dissertations and Doctoral Studies

Breast cancer is a world health problem and is a leading cause of cancer-related death among women in the United States. However, breast cancer risks were reported to be reduced through exposure to Vitamin D through its Receptors identified as the p53 target gene. The purpose of this study was to assess the associations between VDR gene polymorphisms knowledge/awareness and decisions to reduce breast cancer risks and likelihood of mammogram screening among women in Texas. Data from survey were used. Roy adaptation model was the theoretical framework that guided this quasi- experimental, quantitative research. The dependent variables were decisions to …

Giardia Lamblia Growth In Viscoelastic Fluids, Kelly Watanabe

CMC Senior Theses

Giardia lamblia is a single-celled protozoan parasite that when ingested, causes diarrheal disease and infects 33% of people in developing countries. Previous studies observe Giardia in water-like fluids, but Giardia's infectious environment consists of viscoelastic mucus in the small intestine. Therefore, Giardia was cultured in viscoelastic fluids, and its population growth was observed in vitro. To create shear-thinning viscoelastic fluids, 0.2% and 0.4% long-chain polyacrylamide (LCPAM) was added to cell culture media. Giardia was cultured in control media, 0.2% LCPAM, and 0.4% LCPAM, and population growth was quantitatively determined over time. Increasing LCPAM concentration resulted in a solution with …

Mutations Of Fus Cause Aggregation Of Rna Binding Proteins, Disruptions In Protein Synthesis, And Dysregulation Of Nonsense Mediated Decay, Marisa Elizabeth Kamelgarn

Theses and Dissertations--Toxicology and Cancer Biology

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by motor neuron death and subsequent muscle atrophy. Approximately 15% of ALS cases are inheritable, and mutations in the Fused in Sarcoma (FUS) gene contribute to approximately 5% of these cases, as well as about 2% of sporadic cases. FUS performs a diverse set of cellular functions, including being a major regulator of RNA metabolism. FUS undergoes liquid- liquid phase transition in vitro, allowing for its participation in stress granules and RNA transport granules. Phase transition also contributes to the formation of cytoplasmic inclusions found in the …

Effects Of A Systemic High Urea Concentration On The Endometrial And Embryonic Transcriptomes Of The Mare, Yatta Linhares Boakari

Theses and Dissertations--Veterinary Science

Pregnancy loss remains a major source of economic cost to the equine industry. Frequently, the exact causes of pregnancy loss remain unknown. It has been shown, in other species, that increased dietary protein leading to elevated blood urea nitrogen concentrations (BUN) can be a factor in decreased survival of the early embryo. Our studies provided novel information regarding the effects of elevated BUN on endometrium and embryos from mares as well as insights on changes in their gene expression. Our first objective was to develop an experimental model to elevate BUN during diestrus using intravenous urea infusion. We analyzed the …

Mechanisms And Immunogenicity Of Nspef-Induced Cell Death In B16f10 Melanoma Tumors, Alessandra Rossi, Olga N. Pakhomova, Andrei G. Pakhomov, Samantha Weygandt, Anna A. Bulysheva, Len E. Murray, Peter A. Mollica, Claudia Muratori

Bioelectrics Publications

Accumulating data indicates that some cancer treatments can restore anticancer immunosurveillance through the induction of tumor immunogenic cell death (ICD). Nanosecond pulsed electric fields (nsPEF) have been shown to efficiently ablate melanoma tumors. In this study we investigated the mechanisms and immunogenicity of nsPEF-induced cell death in B16F10 melanoma tumors. Our data show that in vitro nsPEF (20-200, 200-ns pulses, 7 kV/cm, 2 Hz) caused a rapid dose-dependent cell death which was not accompanied by caspase activation or PARP cleavage. The lack of nsPEF-induced apoptosis was confirmed in vivo in B16F10 tumors. NsPEF also failed to trigger ICD-linked responses such …

Identifying Critical Genes For Cholesterol Metabolism In Macrophages Using Crispr-Cas9 Whole-Genome Screens, Kevin Wanniarachchi

Electronic Theses and Dissertations

Macrophage foam cells contribute to atherosclerotic plaque formation, a pathology that underlies heart disease, peripheral arterial disease and stroke. Foam cells form when macrophages take up excessive amounts of low-density lipoprotein (LDL) leading to elevated cellular levels of neutral lipids, which are packaged into lipid droplet organelles. Despite the high public health priority motivating research of cardiovascular disease processes, current understanding of macrophage cholesterol metabolism including mechanisms of LDL uptake, cholesterol trafficking, lipid droplet biogenesis, lipid droplet degradation and cholesterol efflux is limited. Here, we implemented a CRISPR-Cas9 whole genome screening strategy to identify critical genes regulating macrophage cholesterol metabolism. …