Biochemistry, Biophysics, and Structural Biology Commons^™

Wnt Secretion Proteins Modulate Rankl-Induced Expression Of Aire In Thymic Epithelial Cells, Daniel Pollack

Dissertations and Theses

Thymic epithelial cells (TEC) are essential for a proper adaptive immune response by regulating thymocyte development and establishing central tolerance. In the thymus, TECs differentially express Wnt proteins, which activate canonical and non-canonical Wnt signaling pathways. Wnt signaling is thought to regulate cell survival, proliferation, and development although the direct molecular mechanisms in TECs have yet to be elucidated. The inducible inhibition of canonical Wnt signaling with Dkk1 leads to a rapid loss of TEC progenitors as well as a decline in mature Aire-expressing mTECs. Therefore, we explore the role of Wnt ligands potentially responsible for stimulating and/or regulating Wnt …

Determining The Role Played By Aryl Hydrocarbon Receptor (Ahr) In The Colon Carcinoma Tumor Model, Poonam Yakkundi

University of the Pacific Theses and Dissertations

Aryl hydrocarbon receptor (AHR), commonly known as an environmental sensor involved in the metabolism and elimination of xenobiotic substances, is also an important modulator in the development and functioning of the immune system. AHR expression is varied in the T cell subsets with the highest expression in T-helper 17 and T regulatory cells. Work from many researchers has suggested that AHR can act as a tumor promoter or a tumor suppressor depending on the tumor type. Our goal is to understand the role played by AHR in MC38 syngeneic colon carcinoma tumor model. In the absence of AHR, MC38 tumor …

Characterization Of Tetraethyl Orthosilicate-Based Dynamic Hydrogels For Use As Reversible 3-D Cell Culture Matrices, Krisitan Stipe

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Peptide-Drug Conjugate For Her2-Targeted Drug Delivery, Yan Wang

University of the Pacific Theses and Dissertations

Recent strategies for anticancer drug design have been focused on utilizing antibody as a drug or targeted moiety for targeted drug delivery. Antibody−drug conjugates (ADCs) have become a promising new class of targeted therapeutic agents for treatment of cancer. ADCs are designed to preferentially direct a cytotoxic drug to a cell-surface antigen recognized by an antibody. However, there are some challenges in developing ADCs, such as limited solid tumor penetration, high manufacturing costs and antibody-drug stoichiometry. Smaller molecules such as peptides have been shown to specifically bind to cancer related targets. These peptides can be used to form peptide-drug conjugates …

Investigations On Cancer Cell Biological Effects Of Cdk8 Inhibitor Q-12, Zhixin Lu

University of the Pacific Theses and Dissertations

Over the past two decades, protein kinases have been intensively investigated as targets to treat neoplastic diseases. Many protein kinase inhibitors not only have therapeutic potential but are becoming invaluable reagents for the study of cell signaling.

We aspired to use our Cyclin-Dependent Kinase 8 inhibitor, Q-12, as a probe for biomarker discovery for CDK8 inhibitor sensitive tumor types. Q-12 shows potent inhibition of cell viability and induction of apoptosis process in some triple-negative breast cancer and colorectal cancer cell lines in vitro. Western blot results indicate that the reduction of STAT1 phosphorylation could be a robust indicator of CDK8 …

Design And In Vitro Characterization Of Lipids With A Ph-Sensitive Conformational Switch And Their Liposomes For Anticancer Drug Delivery, Shen Zhao

University of the Pacific Theses and Dissertations

The traditional anticancer drugs are distributed in vivo through systemic blood circulation with a very small portion reaching the tumor site. Targeted drug delivery systems are developed in efforts to concentrate the drug molecules in the tissue of interest while reducing the drug distribution to healthy tissues to reduce the side effects. Liposomes are colloidal systems composed of amphiphilic molecules that assemble into vesicle structures in aqueous media. They are common carriers for targeted drug delivery with the advantages of low toxicity, low immunogenicity and the ability of encapsulating both lipophilic and hydrophilic drugs.

Prior research indicated the advantages of …

Influence Of The Estrous Cycle And Female Sex Hormones On Ghb Toxicokinetics, Hao Wei

University of the Pacific Theses and Dissertations

Gamma-Hydroxybutyrate (GHB) is an endogenous short-chain fatty acid formed from Gamma-aminobutyric acid (GABA). Clinically, GHB is marketed in the United States as Xyrem to treat narcolepsy with cataplexy and in Europe for the treatment of alcohol withdrawal and narcolepsy. However, the illicit use and abuse of GHB occurs due to its sedative/hypnotic and euphoric effects. Monocarboxylate transporters (MCTs and SMCTs) are integral membrane proteins that control the bidirectional transport of endogenous substrates including lactate, acetate and pyruvate. They have also been found to transport and mediate the clearance and distribution of GHB. MCTs demonstrate a wide tissue distribution, including brain, …

In Vitro Genetic Code Expansion And Selected Applications, Emil S. Iqbal

Theses and Dissertations

The ability of incorporation non-canonical amino acids (ncAAs) using translation offers researchers the ability of extend the functionality of proteins and peptides for many applications including synthetic biology, biophysical and structural studies, and discovery of novel ligands. Here we describe the three projects where the addition of ncAAs to in vitro translation systems creates useful chemical biology techniques. In the first, a fluorinated histidine derivative is used to create a novel affinity tag that allows for the selective purification of peptides from a complex mixture of proteins. In the second, the high promiscuity of an editing-deficient valine-tRNA synthetase (ValRS T222P) …

Evaluation Of Extracellular Matrix Composition And Rheology As Determinants Of Growth, Invasion, And Response To Photodynamic Therapy In 3d Cell Culture Models Of Pancreatic Ductal Adenocarcinoma, Gwendolyn M. Cramer

Graduate Doctoral Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is a notoriously lethal disease characterized by prominent stromal involvement, which plays complex roles in regulating tumor growth and therapeutic response. The extracellular matrix (ECM)-rich stroma has been implicated as a barrier to drug penetration, although stromal depletion strategies have had mixed clinical success. It remains less clear how biophysical interactions with the ECM regulate invasive progression and susceptibilities to specific therapies. Here, an integrative approach combining 3D cell culture and quantitative imaging techniques is used to evaluate invasive behavior and motility as determinants of response to classical chemotherapy and photodynamic therapy (PDT), in which light …

Tfpiα Interacts With Fva And Fxa To Inhibit Prothrombinase During The Initiation Of Coagulation, Jeremy P. Wood, Helle H. Petersen, Bingke Yu, Xiaoai Wu, Ida Hilden, Alan E. Mast

Gill Heart & Vascular Institute Faculty Publications

Tissue factor pathway inhibitor α (TFPIα) inhibits prothrombinase, the thrombin-generating complex of factor Xa (FXa) and factor Va (FVa), during the initiation of coagulation. This inhibition requires binding of a conserved basic region within TFPIα to a conserved acidic region in FXa-activated and platelet-released FVa. In this study, the contribution of interactions between TFPIα and the FXa active site and FVa heavy chain to prothrombinase inhibition were examined to further define the inhibitory biochemistry. Removal of FXa active site binding by mutation or by deletion of the second Kunitz domain (K2) of TFPIα produced 17- or 34-fold weaker prothrombinase inhibition, …

9-Aminoacridine Inhibits Ribosome Biogenesis And Synergizes With Cytotoxic Drugs To Induce Selective Killing Of P53-Deficient Cells, Leonid Anikin, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Common cancer treatments target rapidly dividing cells and do not discriminate between cancer and normal host cells. One approach to mitigating negative side‐effects of cancer treatment is to temporarily arrest cell cycle progression and thus protect normal cells during cytotoxic treatments, a concept called cyclotherapy. We recently proposed that transient inhibition of post‐transcriptional steps of ribosome biogenesis (RBG) can be used to selectively arrest p53‐positive host cells and not p53‐null cancer cells. In this study, we investigated whether cytoprotective RBG inhibition can be achieved through small molecule treatment.

The Role Of Mapk And Scf In The Destruction Of Med13 In Cyclin C Mediated Cell Death, David C Stieg, Stephen D Willis, Joseph Scuorzo, Mia Song, Vidyaramanan Ganesan, Randy Strich, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Departmental Research

In response to stress, the yeast¹ and mammalian² cyclin C translocate from the nucleus to the cytoplasm, where it associates with the GTPase Drp1/Dnm1 to drive mitochondrial fragmentation and apoptosis. Therefore, the decision to release cyclin C represents a key life or death decision. In unstressed cells, the cyclin C‐Cdk8 kinase regulates transcription by associating with the Mediator of RNA polymerase II. We previously reported that the Mediator component Med13 anchors cyclin C in the nucleus³. Loss of Med13 function leads to constitutive cytoplasmic localization of cyclin C, resulting in fragmented mitochondria, hypersensitivity to stress and …

Snf1 Dependent Destruction Of Med13 Is Required For Programmed Cell Death Following Oxidative Stress In Yeast, Stephen D Willis, David C Stieg, R. Shah, Randy Strich, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Departmental Research

All eukaryotic cells, when faced with unfavorable environmental conditions, have to decide whether to mount a survival or cell death response. The conserved cyclin C and its kinase partner Cdk8 play a key role in this decision. Both are members of the Cdk8 kinase module that, along with Med12 and Med13, associate with the core mediator complex of RNA polymerase II. In S. cerevisiae, oxidative stress triggers Med13 destruction¹, which thereafter releases cyclin Ci nto the cytoplasm. Cytoplasmic cyclin C associates with mitochondria where it induces hyper-fragmentation and programmed cell death². This suggests a model in …

Translocation Of Cyclin C During Oxidative Stress Is Regulated By Interactions With Multiple Trafficking Proteins, Daniel G J Smethurst, Katrina F Cooper, Randy Strich

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Eukaryotic cells take cues from their environment and interpret them to enact a response. External stresses can produce a decision between adjusting to behaviors which promote surviving the stress, or enacting a cell death program. The decision to undergo programmed cell death (PCD) is controlled by a complex interaction between nuclear and mitochondrial signals. The mitochondria are highly dynamic organelles that constantly undergo fission and fusion. However, a dramatic shift in mitochondrial morphology toward fission occurs early in the PCD process. We have identified the transcription factor cyclin C as the biochemical trigger for stress‐induced mitochondrial hyper‐fragmentation in yeast (Cooper …

Mechanistic Insights Into The Regulation Of Mitochondrial Fission By Cyclin C, Vidyaramanan Ganesan, Katrina F Cooper, Randy Strich

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Cyclin C is a component of the mediator complex of RNA polymerase II that localizes to the nucleus under normal conditions. In response to stress, cyclin C translocates to the cytosol and mitochondria and mediates stress‐induced mitochondrial fission and apoptosis. The molecular mechanisms by which cyclin C induces mitochondrial fission are unknown. Using in vitro experimental approaches, we sought to investigate the mechanistic basis of cyclin C mediated mitochondrial fission.

Structural And Functional Insights Into The Role Of Bamd And Bame Within The Β-Barrel Assembly Machinery In Neisseria Gonorrhoeae, Aleksandra E. Sikora, Igor H. Wierzbicki, Ryszard A. Zielke, Rachael F. Ryner, Konstantin V. Korotkov, Susan K. Buchanan, Nicholas Noinaj

Molecular and Cellular Biochemistry Faculty Publications

The β-barrel assembly machinery (BAM) is a conserved multicomponent protein complex responsible for the biogenesis of β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria. Given its role in the production of OMPs for survival and pathogenesis, BAM represents an attractive target for the development of therapeutic interventions, including drugs and vaccines against multidrug-resistant bacteria such as Neisseria gonorrhoeae. The first structure of BamA, the central component of BAM, was from N. gonorrhoeae, the etiological agent of the sexually transmitted disease gonorrhea. To aid in pharmaceutical targeting of BAM, we expanded our studies to BamD and BamE within …

Traf3 Negatively Regulates Platelet Activation And Thrombosis, Rui Zhang, Guoying Zhang, Binggang Xiang, Xiaofeng Chen, Lijang Tang, Shaojun Shi, Yani Liu, Xun Ai, Ping Xie, Zhenyu Li

Internal Medicine Faculty Publications

CD40 ligand (CD40L), a member of the tumor necrosis factor (TNF) superfamily, binds to CD40, leading to many effects depending on target cell type. Platelets express CD40L and are a major source of soluble CD40L. CD40L has been shown to potentiate platelet activation and thrombus formation, involving both CD40-dependent and -independent mechanisms. A family of proteins called TNF receptor associated factors (TRAFs) plays key roles in mediating CD40L-CD40 signaling. Platelets express several TRAFs. It has been shown that TRAF2 plays a role in CD40L-mediated platelet activation. Here we show that platelet also express TRAF3, which plays a negative role in …

The Pul37 Tegument Protein Guides Alphaherpesvirus Retrograde Axonal Transport To Promote Neuroinvasion, Alexsia L. Richards, Patricia J. Sollars, Jared D. Pitts, Austin M. Stults, Ekaterina E. Heldwein, Gary E. Pickard, Gregory A. Smith

School of Veterinary and Biomedical Sciences: Faculty Publications

A hallmark property of the neurotropic alpha-herpesvirinae is the dissemination of infection to sensory and autonomic ganglia of the peripheral nervous system following an initial exposure at mucosal surfaces. The peripheral ganglia serve as the latent virus reservoir and the source of recurrent infections such as cold sores (herpes simplex virus type I) and shingles (varicella zoster virus). However, the means by which these viruses routinely invade the nervous system is not fully understood. We report that an internal virion component, the pUL37 tegument protein, has a surface region that is an essential neuroinvasion effector. Mutation of this region rendered …

Validation Of Minimally-Invasive Sample Collection Methods For Measurement Of Telomere Length, Stephanie A. Stout, Jue Lin, Natalie Hernandez, Elysia Poggi Davis, Elizabeth Blackburn, Judith E. Carroll, Laura M. Glynn

Psychology: Faculty Scholarship

Objective: The discovery of telomere length (TL) as a biomarker of cellular aging and correlate of age-related disease has generated a new field of research in the biology of healthy aging. Although the most common method of sample collection for TL is venous blood draw, less-invasive DNA collection methods are becoming more widely used. However, how TL relates across tissues derived from these sample collection methods is poorly understood. The current study is the first to characterize the associations in TL across three sample collection methods: venous whole blood, finger prick dried blood spot and saliva.

Methods: TL …

One-Step Hot Formamide Extraction Of Rna From Saccharomyces Cerevisiae, Daniel Shedlovskiy, Natalia Shcherbik, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Current methods for isolating RNA from budding yeast require lengthy and laborious steps such as freezing and heating with phenol, homogenization with glass beads, or enzymatic digestion of the cell wall. Here, extraction with a solution of formamide and EDTA was adapted to isolate RNA from whole yeast cells through a rapid and easily scalable procedure that does not require mechanical cell lysis, phenol, or enzymes. RNA extracted with formamide-EDTA can be directly loaded on gels for electrophoretic analysis without alcohol precipitation. A simplified protocol for downstream DNase treatment and reverse transcription reaction is also included. The formamide-EDTA extraction of …

Brain Energy Homeostasis And The Regulation Of N-Acetyl-Aspartate Metabolism In Development And Disease, Samantha Zaroff

Graduate School of Biomedical Sciences Theses and Dissertations

N-acetylaspartate (NAA) is a non-invasive clinical marker of neuronal metabolic integrity because of its strong proton magnetic resonance spectroscopy (H-MRS) peak and direct correlation with energetic integrity. Specifically, NAA is used to track the progression of neurodegenerative diseases due to the characteristic reduction of whole brain levels of NAA which occur simultaneously with reduced glucose utilization and mitochondrial dysfunction, but prior to the onset of disease specific pathology. However, NAA will also significantly increase simultaneously with energetic integrity during periods of recovery or remission in applicable disorders, such as traumatic brain injuries. Unfortunately, it remains enigmatic exactly why NAA is …

Zika Virus Encoding Nonglycosylated Envelope Protein Is Attenuated And Defective In Neuroinvasion, Arun S. Annamalai, Aryamav Pattnaik, Bikash R. Sahoo, Ezhumalai Muthukrishnan, Sathish Kumar Natarajan, David Steffen, Hiep Vu, Gustavo Delho, Fernando Osorio, Thomas M. Petro, Shi-Hua Xiang, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Zika virus (ZIKV), a mosquito-transmitted flavivirus responsible for sporadic outbreaks of mild and febrile illness in Africa and Asia, reemerged in the last decade causing serious human diseases, including microcephaly, congenital malformations, and Guillain-Barré syndrome. Although genomic and phylogenetic analyses suggest that genetic evolution may have led to the enhanced virulence of ZIKV, experimental evidence supporting the role of specific genetic changes in virulence is currently lacking. One sequence motif, VNDT, containing an N-linked glycosylation site in the envelope (E) protein, is polymorphic; it is absent in many of the African isolates but present in all isolates from the recent …

Type Ix Secretion System: Characterization Of An Effector Protein And An Insight Into The Role Of C-Terminal Domain Dimeration In Outer Membrane Translocation., Lahari Koneru

Electronic Theses and Dissertations

Porphyromonas gingivalis and Tannerella forsythia are two of the primary pathogens that are associated in the etiology and progression of chronic periodontitis. In T. forsythia, KLIKK proteases are the recently identified group of proteolytic enzymes that are secreted through Type IX secretion system (T9SS). Among, these KLIKK proteases a synergistic relationship was observed between karilysin and mirolysin in invading the host complement system for the survival of the bacteria. Since, karilysin has been already characterized, in this study we propose to study about mirolysin through structural, biochemical and biological characterization. The obtained results from the experiments has shown the …

Developing Algorithms For Quantifying The Super Resolution Microscopic Data: Applications To The Quantification Of Protein-Reorganization In Bacteria Responding To Treatment By Silver Ions, Sai Divya Challapalli

Graduate Theses and Dissertations

Histone-like nucleoid structuring proteins (HNS) play significant roles in shaping the chromosomal DNA, regulation of transcriptional networks in microbes, as well as bacterial responses to environmental changes such as temperature fluctuations. In this work, the intracellular organization of HNS proteins in E. coli bacteria was investigated utilizing super-resolution fluorescence microscopy, which surpasses conventional microscopy by 10–20 fold in spatial resolution. More importantly, the changes of the spatial distribution of HNS proteins in E. coli, by addition of silver ions into the growth medium were explored. To quantify the spatial distribution of HNS in bacteria and its changes, an automatic method …

Zika Virus Encoding Nonglycosylated Envelope Protein Is Attenuated And Defective In Neuroinvasion, Arun Saravanakumar Annamalai, Aryamav Pattnaik, Bikash R. Sahoo, Ezhumalai Muthukrishnan, Sathish Kumar Natarajan, David Steffen, Hiep Vu, Gustavo A. Delhon, Fernando Osorio, Thomas M. Petro, Shi-Hua Xiang, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

ABSTRACT Zika virus (ZIKV), a mosquito-transmitted flavivirus responsible for sporadic outbreaks of mild and febrile illness in Africa and Asia, reemerged in the last decade causing serious human diseases, including microcephaly, congenital malformations, and Guillain-Barré syndrome. Although genomic and phylogenetic analyses suggest that genetic evolution may have led to the enhanced virulence of ZIKV, experimental evidence supporting the role of specific genetic changes in virulence is currently lacking. One sequence motif, VNDT, containing an N-linked glycosylation site in the envelope (E) protein, is polymorphic; it is absent in many of the African isolates but present in all isolates from the …

The Functions Of Setd5 And Mir-221 In Embryonic Stem Cell Differentiation, Tsai-Yu Chen

Dissertations and Theses (Open Access)

Embryonic stem cells (ESCs) are a widely used model system to study cellular differentiation because of their pluripotent characteristics, and ESC differentiation is an epigenetic process. In an effort to identify a new epigenetic factor that is required for ESC differentiation, the function of SETD5 in ESCs was studied for this thesis. Results show that SETD5 is essential for retinoic acid (RA)-induced differentiation of mouse ESCs and for RA-induced expression of critical developmental genes (e.g., Hoxa1 and Hoxa2) and neuron-related genes (e.g., Nestin and Pax6). SETD5 was upregulated during ESC differentiation. Additional results demonstrated that SETD5 bound to …

Insights Into The Therapeutic Potential Of Salt Inducible Kinase 1: A Novel Mechanism Of Metabolic Control, Randi Fitzgibbon

Dissertations and Theses (Open Access)

Salt inducible kinase 1 (SIK1) has been considered a stress-inducible kinase since it was first cloned in 1999. Continued efforts since this time have been dedicated to characterizing the structure and function of SIK1. Such research has laid the ground work for our understanding of SIK1 action and regulation in tissue and stimuli dependent manners. The fundamental findings of this dissertation continue in this tradition and include investigations of SIK1 regulatory mechanisms in skeletal muscle cells, the cellular and physiological effects of SIK1 loss of function in vitro and in vivo, and intracellular metabolic and mitochondrial regulation by this …

Endocytic Trafficking Of The Amyloid Precursor Protein In Rat Cortical Neurons, Sahily Reyes

Dissertations and Theses (Open Access)

Amyloid-beta (Aβ) aggregation and deposition into extracellular plaques is a hallmark of the most common forms of dementia, including Alzheimer’s disease. The Aβ-containing plaques result from pathogenic cleavage of amyloid precursor protein (APP) by secretases resulting in intracellular production of Aβ peptides that are secreted and accumulate extracellularly. Despite considerable progress towards understanding APP processing and Aβ aggregation, the mechanisms underlying endosomal production of Aβ peptides and their secretion remain unclear. Using endosomes isolated from cultured primary neurons, we determined that the trafficking of APP from the endosomal membrane into internal vesicles of late endosome/multivesicular bodies (MVB) is dependent on …

Role Of Cannabinoid Receptor Type 2 (Cb2) In Late Stage Atherosclerosis, Makenzie Fulmer

Electronic Theses and Dissertations

Atherosclerosis is a chronic inflammatory disorder of medium and large vessels. Immune signaling and dyslipidemia are two of several processes which influence lesion development in atherosclerosis. Cannabinoids, such as those found in marijuana, exert their effects through two cannabinoid receptors, CB1 and CB2. Recent studies using CB2 knockout mice and CB2-selective ligands have shed light on a protective role of CB2 in early stages of atherosclerosis. However, the role of CB2 in advanced stages of atherosclerosis remains unclear. To determine if CB2 plays a role in advanced atherosclerotic lesion composition and progression, we investigated the effects of systemic CB2 gene …

Harmonizing Lipidomics: Nist Interlaboratory Comparison Exercise For Lipidomics Using Srm 1950-Metabolites In Frozen Human Plasma, J Bowden, C Ulmer, C Jones, J Koelmel, L Abdullah, Houli Jiang, Michal Schwartzman, Amaury Cazenave-Gassiot, Antonio Checa, Michelle Cinel, Romain Colas, Serge Cremers, Edward Dennis, James Evans, Alexander Fauland, Jun Han, Houli Jiang, Michal Schwartzman

NYMC Faculty Publications

As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks …