Biochemistry, Biophysics, and Structural Biology Commons^™

Newer Insights Into Mmtv Replication: The Human Retroviral Proteins Hiv-1 Tat And Htlv-1 Tax Can Transactivate The Mmtv Novel 5’ Element, Thanumol Abdul Khader

Dissertations

The mouse mammary tumor virus (MMTV) is a prototypic betaretrovirus that causes breast cancer in mice. MMTV regulates its gene expression both at the transcriptional and post transcriptional levels. It has hormonally-regulated promoters controlled by negative regulatory factors in a tissue-specific manner. Recently, we identified a novel 24-nucleotide region at the 5' end of the MMTV genome crucial for MMTV gene expression. Its deletion resulted in disruption of MMTV transcript elongation and stability, leading to a complete loss of Gag gene expression. This conserved element is present within the bifurcated stem loop 4, responsible for gRNA dimerization and encapsidation, into …

Evaluation Of Rotenone Mediated Α-Synuclein Spreading And Neurotoxicity In Intra-Striatal Injection Of Α-Synuclein Pff Model Of Parkinson’S Disease, Engila Khan

Theses

In the last 25 years, the prevalence of Parkinson’s Disease (PD) across the globe has doubled. Clinical manifestations of this progressive neurodegenerative disorder include motor symptoms such as tremors, bradykinesia, postural instability, etc., which occur due to selective loss of dopaminergic neurons in the Substantia nigra (SNC) in the brain. The histopathological feature of PD is the presence of intra-neuronal aggregates of proteins called Lewy bodies, a major constituent of which is α-synuclein (α-syn).

Epidemiological studies to date have reported a connection between exposure to environmental neurotoxins such as Rotenone (a mitochondrial complex 1 inhibitor) and increased risk of PD …

Anti Cancer Activity Of Rhus Coriaria (Sumac) Against 5-Fluorouracil-Resistant Colorectal Cancer Cells, Zohra Nausheen Nizami

Theses

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths, both worldwide and in the UAE. 5-Fluorouracil (5-FU), a pyrimidine analogue, is a chemotherapeutic agent that is an integral component of chemotherapy regimens for CRC treatment. However, 5-FU resistance (intrinsic and/or acquired) inhibits their clinical efficacy. In recent years, there has been a growing popularity for plant-based cancer therapeutics, specifically using phytochemical compounds. Rhus coriaria (Sumac) is a Mediterranean plant whose fruits are used as a spice and medicinal herb. Extracts of Rhus coriaria fruits (RCE) have been reported to exhibit anti-cancer activity against breast cancer and CRC. In …

Modulation Of Chronic Allergic Contact Dermatitis Through B Cells, Sara Saeed Alhmoudi

Theses

Allergic contact dermatitis (ACD) is a common inflammatory disease caused by contact with an allergen and is a T-cell-mediated type IV hypersensitivity reaction. Shortchain fatty acids (SCFAs) showed the ability to modulate immune cells in case of inflammation. Pentanoate is one of the abundant SCFA that showed therapeutic ability by inducing interleukin-10 (IL-10) secretion in lymphocytes. IL-10-producing regulatory B cells have been shown to decrease different inflammatory responses; however, the overall role of B cells in ACD is not well studied. This project aims to explore the role of B cells during chronic ACD and their modulation with the SCFA …

Changes In Lipid Profiles Of Epileptic Mouse Model, Alicia Johnson, Ryan A. Grove, Deepak Madhavan, Cory Honsinger Thomas Boone, Camila Pereira Braga, Hannah Kyllo, Kaeli Samson, Timothy Simeone, Tomáš Helikar, Corrine K. Hanson, Jiri Adamec

Department of Biochemistry: Faculty Publications

Introduction—Approximately 1% of the world’s population is impacted by epilepsy, a chronic neurological disorder characterized by seizures. One-third of epileptic patients are resistant to AEDs, or have medically refractory epilepsy (MRE). One non-invasive treatment that exists for MRE includes the ketogenic diet, a high-fat, low-carbohydrate diet. Despite the KD’s success in seizure attenuation, it has a few risks and its mechanisms remain poorly understood. The KD has been shown to improve metabolism and mitochondrial function in epileptic phenotypes. Potassium channels have implications in epileptic conditions as they have dual roles as metabolic sensors and control neuronal excitation.

Objectives—The …

Probing The Consequences Of Irreversibly Trapping Iron In Bacterioferritin Using Chemical And Genetic Approaches--An Omics Study, Leo S. Fontenot Jr.

LSU Doctoral Dissertations

Antibiotic resistant bacteria pose one of the most urgent threats to public health. Pseudomonas aeruginosa is a multi-drug resistant bacterium for which new antibiotics are urgently needed. My research is focused on understanding and validating iron metabolism as a target for antibiotic development by analyzing the metabolic profiles of iron-starved P. aeruginosa cells caused by irreversibly trapping iron in bacterioferritin. Iron is an essential nutrient for bacteria; however, the reactivity of the Fe²⁺ ion and insolubility of the Fe³⁺ ion present significant challenges to bacterial cells. Iron storage proteins oxidize Fe²⁺ using O₂ and H_{2 …}

Yeast Crf1p: An Activator In Need Is An Activator Indeed, Sanjay Kumar

LSU Doctoral Dissertations

Ribosome biogenesis is an energetically costly process, and tight regulation is required for stoichiometric balance between components. This requires coordination of RNA polymerases I, II, and III. Lack of nutrients or the presence of stress leads to downregulation of ribosome biogenesis, a process for which mechanistic target of rapamycin complex I (mTORC1) is key. mTORC1 activity is communicated by means of specific transcription factors, and in yeast, which is a primary model system in which transcriptional coordination has been delineated, transcription factors involved in regulation of ribosomal protein genes include Fhl1p and its cofactors, Ifh1p and Crf1p. Ifh1p is an …

Neuroendocrine Regulation Of Chemokine Receptor-Mediated Leukocyte Migration Via Heteromeric G Protein-Coupled Receptor Complexes, Garrett Enten

USF Tampa Graduate Theses and Dissertations

Neuroendocrine regulation of the innate immune system is a well-documentedphenomenon. The underlying mechanisms, however, are not well understood. Here we show that at least 20 members of the human chemokine receptor (CR) family heteromerize with one or more members of the α1-adrenergic receptor (AR) family and that all CRs, apart from CXCR1, heteromerize with arginine vasopressin receptor 1A (AVPR1A) in recombinant systems. These heteromeric complexes are detectable in human monocytes and the monocytic leukemia cell line THP-1. Though currently technical limitations prevent the direct visualization of endogenously expressed higher-order hetero-oligomeric receptor complexes, we provide evidence through functional analysis and proximity-based …

Structural And Functional Characterizations Of The Two Mini-Ferritins In Pseudomonas Aeruginosa Revealed The Coexistence Of A Classic Dps (Pa0962) And A Dps-Like (Pa4880) Protein, Rajapaksha Pathirannahalage Nimesha Hansani Rajapaksha

LSU Doctoral Dissertations

In the P. aeruginosa genome, gene PA0962 codes for a probable DNA-binding protein from starved cells (Pa Dps). Pa Dps is assembled from 12 monomers, each consisting of a four-helix bundle fold typical of Dps proteins. A subunit dimer of Pa Dps harbors two ferroxidase centers. Assembly of a dodecameric structure of Pa Dps is favored by the presence of divalent metal ions and at pH 6.0 in the absence or presence of divalent cations. Pa Dps is unable to form the large DNA-protein complexes typical of many Dps proteins. Instead, Pa Dps acts on plasmid DNA to form relaxed …

Substrate Specificity In Abc Transporters Using The E. Coli Methionine Import System, John H. Guardado

Featured Student Work

ATP-binding cassette (ABC) transporters use the energy of ATP to move substrates across membranes against a concentration gradient. The role of ABC transporters is crucial in several essential cellular functions and mutations in ABC transporters in humans have been linked to several conditions, including cystic fibrosis, liver disease, and diabetes. Despite their central roles in homeostasis, the mechanism of ABC transporters remains poorly understood. Our research is focused on studying an ABC importer in E. coli, as a model system, to examine the mechanism of substrate specificity and transport. The bacterial methionine import system consists of a membrane-embedded transporter, MetNI, …

The Effects Of Vaping Coil Temperature On The Viability Of Veillonella Parvula And Streptococcus Mutans, Marvelous O. Aluko

Harrisburg University Research Symposium: Highlighting Research, Innovation, & Creativity

No abstract provided.

Using Hyperosmotic Shock To Study The Cell Wall Of Myxococcus Xanthus, Ian Sabol

Harrisburg University Research Symposium: Highlighting Research, Innovation, & Creativity

No abstract provided.

Effects Of Growth Rate On Peptidoglycan Crosslink Density Of E. Coli Using Fluorescent Labeling, Morgan Olszewski

Harrisburg University Research Symposium: Highlighting Research, Innovation, & Creativity

Peptidoglycan (PG) is a polymer composed of polysaccharides and crosslinked peptide chains found in bacterial cell walls. It helps to protect the cell from environmental stress and maintain cell morphology throughout its life cycle and further generations. The PG is made up of two sugars, N-acetyl muramic acid (NAM) and N-acetyl glucosamine (NAG). NAM and NAG are connected by glycosidic linkages to form repeated chains. The chains are formed in layers, which are interconnected via a polypeptide stem linked by a peptide bridge. During cell growth, continuous turnover of existing PG occurs by severing existing crosslinks, inserting new PG into …

Thermodynamic Frustration Of Tad2 And Prr Contribute To Autoinhibition Of P53, Emily Gregory

USF Tampa Graduate Theses and Dissertations

The intrinsically disordered transcription factor and tumor suppressor p53 binds to promoter response element DNA upon cellular stress and activates genes associated with cell cycle arrest, senescence, and apoptosis. Disruption of sequence specific binding to target gene promoters is heavily implicated in human health, where a majority of cancers contain mutations localized to the DNA binding domain (DBD) of p53. p53 DNA binding is regulated by posttranslational modifications, associations with cellular factors, and by an autoinhibitory intramolecular interaction. The autoinhibitory intramolecular interaction occurs when the disordered N-terminal transactivation domain (TAD) interacts with the ordered DBD. Previous work in the Daughdrill …

Bola3 And Nfu1 Link Mitoribosome Iron–Sulfur Cluster Assembly To Multiple Mitochondrial Dysfunctions Syndrome, Hui Zhong, Alexandre Janer, Oleh Khalimonchuk, Hana Antonicka, Eric A. Shoubridge, Antoni Barrientos

Department of Biochemistry: Faculty Publications

The human mitochondrial ribosome contains three [2Fe–2S] clusters whose assembly pathway, role, and implications for mitochondrial and metabolic diseases are unknown. Here, structure-function correlation studies show that the clusters play a structural role during mitoribosome assembly. To uncover the assembly pathway, we have examined the effect of silencing the e xpression of Fe–S cluster biosynthetic and delivery factors on mitoribosome stability. We find that the mitoribosome receives its [²Fe–2S] clusters from the GLRX5-BOLA3 node. Additionally, the assembly of the small subunit depends on the mitoribosome biogenesis factor METTL17, recently reported containing a [⁴Fe–4S] cluster, which we …

Novel Treatments For Pxe: Targeting The Systemic And Local Drivers Of Ectopic Calcification, Ida Joely Jacobs, Qiaoli Li

Department of Biochemistry and Molecular Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable multisystem ectopic calcification disorder. The gene responsible for PXE, ABCC6, encodes ABCC6, a hepatic efflux transporter regulating extracellular inorganic pyrophosphate (PPi), a potent endogenous calcification inhibitor. Recent studies demonstrated that in addition to the deficiency of plasma PPi, the activated DDR/PARP signaling in calcified tissues provides an additional possible mechanism of ectopic calcification in PXE. This study examined the effects of etidronate (ETD), a stable PPi analog, and its combination with minocycline (Mino), a potent inhibitor of DDR/PARP, on ectopic calcification in an Abcc6-/- mouse model of PXE. Abcc6-/- mice, at 4 weeks of …

Molecular Event In Hrp Apoptosis, Laura Valdez

Research Colloquium

Background: Human retinal pericytes (HRP) are contractile cells providing support for endothelial cells of capillaries, essential in the regulation of retinal vasculature. Early stages of DR are characterized by the loss of HRP, leading to angiogenesis. Our preliminary studies identified monocyte-derived macrophages secrete TGF-β1, inducing the expression and secretion of a TGFβ1-Induced, pro-apoptotic BIGH3 protein leading to apoptosis of HRP. Based on a preliminary study in renal cells (unpublished data), CTP with an RGD domain is released from BIGH3 by proteolysis leading to renal cell apoptosis. In the present study, we employed Western Blots to determine if a similar molecular …

Irbp In Diabetic Retinopathy – Cell Culture & Ophthalmic Pathology Studies, Laura Valdez

Research Colloquium

Background: Interphotoreceptor-Retinoid-Binding-Protein (IRBP) is restricted to the subretinal space by the external limiting membrane and RPE zonulae occludens. Its expression is reduced in diabetic retinopathy (DR) and increased expression is protective. Hypoxia decreases viable conelike photoreceptors (661W) but increased VEGF, suggesting a role of photoreceptors in proliferative DR (PDR) (Rodriguez et al, Arch Clin Exp. Ophthal 3:23,2021). Here, we investigated the effects of high glucose and VEGF on IRBP expression by 661W and rod-like Y79 cells and distribution of IRBP and albumin in human globes with PDR and NPDR.

Methods:  661W and Y79 cells were cultured in DMEM or RPMI …

Xrk3f2 Inhibits P62 Signaling And Augments Myeloma Killing By Proteasome Inhibitors, Ellen Trautman, Colin Crean, David Halladay, Attaya Suvannasankha

Annual Student Research Poster Session

Background:

Despite advancements in therapy, multiple myeloma (MM) remains an incurable blood cancer. Our mission is to maximize the efficacy of a primary treatment for myeloma, proteasome inhibitors (PIs) which cause intracellular waste buildup, leading to ER stress and cell death. p62(sequestosome-1) provides an alternate pathway when the proteasome is inhibited, by breaking down cytotoxic material via autophagy. Upregulation of p62 is associated with PI resistance. We identified a small molecule, XRK3F2, that binds to the ZZ domain of p62 and inhibits its autophagic function. We hypothesized that XRK3F2 would improve MM killing when combined with PIs.

Methods Used:

We …

Sars-Cov-2: Tale Of A Microscopic Murderer, Josiah P. Garner

Quest

Independent Study

Research in progress for BIOL1406: Biology for Science Majors I

Faculty Mentor: Amina Tassa, Ph.D.

I am delighted to introduce Josiah Garner’s “SARS-CoV-2: Tale of a Microscopic Murderer.” This independent study assignment explores the impact of a novel, deadly, and worldwide virus. The assignment also examines the fast development of vaccines to control the spread and reduce the symptoms of the virus.

Josiah’s paper focuses on the early history of the emergence of COVID-19, the world response, and vaccine development. He demonstrates critical thinking skills and effectively utilizes various research methods to obtain and communicate his information. Josiah …

Characterizing The Utility Of A Near Infrared Click Beetle Luciferase For Bli Applications, Giovanni Duca

Master's Theses

Bioluminescent imaging systems (BLI) have become a valuable tool for doing real-time in vivo studies. BLI systems typically allow for the imaging of surface and subsurface level tissues but as depth increases, the resolution decreases while the signal to noise ratio increases. Deep tissue imaging is therefore a major limitation for BLI. To address this limitation there has been a consistent movement in luciferase research to create long wavelength emitting luciferases that still have a high photon emission rate. Longer wavelengths of light are able to penetrate deeper tissues due to having a lower amount of absorbance and scattering from …

Raman Spectral Cytopathology For Cancer Diagnostic Applications, Fiona Lyng, Damian Traynor, Isha Behl, Declan O'Dea, Hugh Byrne

Books/Book Chapters

Histopathology is currently regarded as the “gold standard” patient sampling technique for cancer diagnostics. It involves extraction of a tissue sample, or biopsy, which is then sectioned and stained for evaluation by a pathologist [1]. Cytopathology, on the other hand, is the field of disease diagnosis at the cellular level [2], necessitating only the microscopic evaluation of samples of cells which can be harvested by less invasive methods such as exfoliative brushing, needle probes or from biofluids. Based on the identification of abnormalities in cellular appearance, cytopathology is currently widely used to aid in the screening of cancer, as well …

Factors Influencing Instructors’ Adoption And Continued Use Of Computing Science Technologies: A Case Study In The Context Of Cell Collective, Changsoo Song, Resa M. Helikar, Wendy Smith, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Acquiring computational modeling and simulation skills has become ever more critical for students in life sciences courses at the secondary and tertiary levels. Many modeling and simulation tools have been created to help instructors nurture those skills in their classrooms. Understanding the factors that may motivate instructors to use such tools is crucial to improve students’ learning, especially for having authentic modeling and simulation learning experiences. This study designed and tested a decomposed technology acceptance model in which the perceived usefulness and perceived ease of use constructs are split between the teaching and learning sides of the technology to examine …

College Of Natural Sciences Newsletter, September - October 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 2 New Faculty an Staff for the Fall 2023 Semester
Page 3 Awards
Page 4 Student Ambassadors in CNS
Page 5 Meet our Jacks
Page 6-8 Events
Page 9-11 Media Coverage of CNS
Page 12-13 Spring 2023 Dean's List
Page 14 Open PRAIRIE Data

Computational Investigation Of Mononuclear Iron Water Oxidation Catalyst Design, Kristal Stevens, Emily Jarvis

Chemistry and Biochemistry Faculty Works

Hydrogen production from non-carbon sources is an essential component of clean and sustainable technology for reducing greenhouse gas emissions from fuels. Water oxidation, which splits water molecules into hydrogen (protons) and molecular oxygen, is a thermodynamically challenging, multistep reaction achieved in photosynthetic organisms via photocatalysis by the Oxygen Evolving Complex (OEC) of Photosystem II. Mononuclear water oxidation catalysts that aim to mimic nature typically rely on heavy, rare metals such as ruthenium and iridium. Replacing these metals with iron is particularly appealing because it is abundant, benign, and inexpensive. We use density functional theory to characterize the catalytic ability of …

Structural Insights Into The Cl-Par-4 Protein: Ionic Requirements, Conformational Transitions, And Interaction With Cisplatin, Krishna Kumar Raut

Chemistry & Biochemistry Theses & Dissertations

Cancer continues to be the leading global cause of death, with challenges in early diagnosis, drug resistance, non-specific drug targeting, and cancer recurrence and metastasis posing formidable obstacles in cancer therapy. In this context, Prostate Apoptosis Response-4 (Par-4), a pro-apoptotic tumor suppressor protein, emerged as a promising therapeutic target due to its ability to selectively induce apoptosis in cancer cells, thereby minimizing the drug-associated adverse effects. However, a comprehensive understanding of the structural features of Par-4, specifically the caspase-cleaved fragment (cl-Par-4), is crucial for therapeutic advancements.

This dissertation investigated the effects of various ions, both monovalent and divalent, on the …

Copy Number Variation That Influences The Ionizing Radiation Sensitivity Of Oral Squamous Cell Carcinoma, Tadahide Izumi, Piotr G. Rychahou, Li Chen, Molly H. Smith, Joseph Valentino

Markey Cancer Center Faculty Publications

Genome instability in cancer cells causes not only point mutations but also structural variations of the genome, including copy number variations (CNVs). It has recently been proposed that CNVs arise in cancer to adapt to a given microenvironment to survive. However, how CNV influences cellular resistance against ionizing radiation remains unknown. PRMT5 (protein arginine methyltransferase 5) and APE1 (apurinic/apyrimidinic endonuclease 1), which enhance repair of DNA double-strand breaks and oxidative DNA damage, are closely localized in the chromosome 14 of the human genome. In this study, the genomics data for the PRMT5 and APE1 genes, including their expression, CNVs, and …

Distinct Camp Signaling Microdomains Differentially Regulate Melanosomal Ph And Pigmentation, Maftuna Yusupova, Dalee Zhou, Jaewon You, Jeydi Gonzalez-Guzman, Megha B. Ghanta, Hong Pu, Zalfa Abdel-Malek, Qiuying Chen, Steven S. Gross, John August D'Orazio, Shosuke Ito, Kazumasa Wakamatsu, Melissa L. Harris, Jonathan H. Zippin

Markey Cancer Center Faculty Publications

cAMP signaling is a well-established regulator of melanin synthesis. Two distinct cAMP signaling pathways—the transmembrane adenylyl cyclase pathway, activated primarily by the MC1R, and the soluble adenylyl cyclase (sAC) pathway—affect melanin synthesis. The sAC pathway affects melanin synthesis by regulating melanosomal pH, and the MC1R pathway affects melanin synthesis by regulating gene expression and post-translational modifications. However, whether MC1R genotype affects melanosomal pH is poorly understood. We now report that loss of function MC1R does not affect melanosomal pH. Thus, sAC signaling appears to be the only cAMP signaling pathway that regulates melanosomal pH. We also addressed whether MC1R genotype …

Phosphatidic Acid Binding To Patched Contributes To The Inhibition Of Smoothened And Hedgehog Signaling In Drosophila Wing Development, Jie Zhang, Yajuan Liu, Chi Wang, Craig W. Vander Kooi, Jianhang Jia

Markey Cancer Center Faculty Publications

Hedgehog (Hh) signaling controls growth and patterning during embryonic development and homeostasis in adult tissues. Hh binding to the receptor Patched (Ptc) elicits intracellular signaling by relieving Ptc-mediated inhibition of the transmembrane protein Smoothened (Smo). We uncovered a role for the lipid phosphatidic acid (PA) in the regulation of the Hh pathway in Drosophila melanogaster. Deleting the Ptc C-terminal tail or mutating the predicted PA-binding sites within it prevented Ptc from inhibiting Smo in wing discs and in cultured cells. The C-terminal tail of Ptc directly interacted with PA in vitro, an association that was reduced by Hh, and increased …

Regulated Translocation Of Neutral Sphingomyelinase-2 To The Plasma Membrane Drives Insulin Resistance In Steatotic Hepatocytes, Salim S. El-Amouri, Alexander A. Karakashian, Erhard Bieberich, Mariana N. Nikolova‑Karakashian

Markey Cancer Center Faculty Publications

Abstract Obesity-associated diabetes is linked to the accumulation of ceramide in various organs, including the liver. The exact mechanisms by which ceramide contributes to diabetic pathology are unclear, but one proposed scenario is that ceramide accumulation may inhibit insulin signaling pathways. It is unknown however whether the excess ceramide is generated proximal to the insulin receptor, that is, at the plasma membrane (PM), where it could affect the insulin signaling pathway directly, or the onset of insulin resistance is due to ceramide- induced mitochondrial dysfunction and/or lipotoxicity. Using hepatic cell lines and primary cultures, gain- and loss- of function approach, …