Biochemistry, Biophysics, and Structural Biology Commons^™

Role Of Na⁺/K⁺-Atpase And Sodium–Calcium Exchanger In Digitoxin-Induced Cytotoxicity In Triple Negative Breast Cancer Cells, Alyson Sotomayor Quispe, Marilyn Odom Phd

SPARK Symposium Presentations

Triple Negative Breast Cancer (TNBC) is characterized by the absence of estrogen, progesterone, and HER2 receptors, limiting targeted treatment options. Digitoxin, a drug used to treat heart failure and atrial fibrillation through Na⁺/K⁺-ATPase inhibition, has demonstrated anticancer effects in TNBC cells, including apoptosis via the NF-κB pathway. This study investigates whether the Na⁺/K⁺-ATPase and sodium–calcium exchanger contribute to the mechanism of action of digitoxin in TNBC cells. We hypothesize that these transporters mediate digitoxin-induced cytotoxic effects. To test this, MDA-MB-468 cells were treated with digitoxin, and protein localization and expression were analyzed using immunofluorescence and Western blot. Digitoxin treatment resulted …

Contribution Of G4 Structure To Alzheimer’S Disease And Tau Pathology, Lena Michaela Kallweit

Electronic Theses and Dissertations

The occurrence of Alzheimer’s Disease (AD) is rapidly increasing as our global population ages. With the majority of therapeutic drugs in the last couple of decades failing clinical trials, new molecular targets are needed to combat the expected influx of new AD cases. AD pathogenesis is associated with abnormal protein aggregation, characterized in part by intracellular accumulation of hyperphosphorylated tau (p-tau) in neurofibrillary tangles (NFTs). RNA has been identified as a major non-proteinaceous component of NFTs and has been implicated as an active cofactor in tau aggregation and spread. Recent work has shown that aggregates from AD brains contain almost …

Disrupted Nuclear Function And Nucleocytoplasmic Transport In Parkinson’S Disease, Ichiro M. Matoba

The Cardinal Edge

No abstract provided.

College Of Natural Sciences 2025 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 2 Dean's Message 
Page 3 Department Highlights 
Page 4 One Day for State 
Page 5 Ice cores reveal volcanic eruptions in 13th century 
Page 5 How do our cells interpret stress 
Page 6-7 Faculty Excellence
Page 8 New chemical biology consortium will accelerate cancer research
Page 9 SDSU to combat crop disease, biofilms in new NSF-back project 
Page 9 Science as Art Competition 
Page 10-11 Student Excellence  
Page 12 SDSU researcher developing natural alternative to synthetic dyes
Page 12 Browning Retired
Page 13 Quantum technologies through NSF-backed project
Page 13 NASA Funds CNS Development of Model
Page 14 GGS …

Characterization And Advancement Of Molluscan Venom Gland Cell Model Systems, James V. Parziale

Dissertations, Theses, and Capstone Projects

Venomous mollusks, including cone snails and coleoid cephalopods, produce rich repertoires of bioactive peptides with profound effects on cellular physiology, yet there are few tractable experimental systems that exist to study their development, maintenance, and venom secretion. Although therapeutics such as the cone snail peptide Ziconotide demonstrate the biomedical potential of molluscan venoms, progress in understanding how venom glands form, function, and evolve has been hindered by the lack of reliable husbandry and the complete absence of in vitro cell models. Modern comparative genomics has revealed widespread convergent evolution across venomous lineages, but molluscan datasets remain underrepresented, limiting insights into …

An Antioxidant Cocktail Of Tert-Butylhydroquinone And A Manganese Porphyrin Induces Toxic Levels Of Oxidative Stress In Cancer Cells, Sandra Tamarin, Hannah Jung, Joseph Lamorte, Laura Biesterveld, Gabriel Piñero, Grace Turchetta, Molly Myers, Rebecca Oberley-Deegan, Aimee Eggler

Student Papers, Posters & Projects

Despite significant advancement in cancer treatments, therapies with minimal toxicity to healthy cells are still limited. One targetable weakness of cancer cells is their sensitivity to oxidative stress. We find that the combination of two antioxidants—the common food additive tert-butylhydroquinone (tBHQ) and a manganese porphyrin in clinical trials, MnTnBuOE-2-PyP5+ (MnBuOE)—increases oxidative stress and causes apoptotic death in several cancer cell lines, but not in mouse primary fibroblasts. Investigating the mechanism of cell death, MnBuOE is observed to catalyze the oxidation of tBHQ, producing the electrophilic quinone tert-butylquinone (tBQ). A critical role for tBQ and its electrophilic character was revealed with …

Dapagliflozin Attenuates Cisplatin-Induced Nephrotoxicity In Rats Through Modulation Of Ros/Nf-Κb, Bcl2/Bax And Pink1/Parkin Signaling Pathways, Esraa K. Khallaf, Eman A. Ramadan, Mohey M. Elmazar, Marwa M. Safar

Pharmacy

Dapagliflozin (DPG), an anti-diabetic drug, has gained attention for its renal protective effects through multiple molecular pathways, yet its impact on mitophagy in cisplatin (CIS) nephrotoxicity remains unclear. This study aimed to examine the impact of DPG against CIS-induced nephrotoxicity in rats, targeting mainly PINK1/Parkin-mediated mitophagy and inflammatory/apoptotic pathways. Male Sprague Dawley rats received DPG (10 mg/kg; p.o) daily for 14 consecutive days and AKI was induced by a single injection of CIS (7 mg/kg; i.p) on day 10. Blood glucose, serum levels of creatinine and urea nitrogen, oxidative stress, inflammatory, apoptotic, mitophagy markers, and histological changes were assessed. DPG …

Generating A Gfp Reporter Via Crispr To Visualize Ssa4 Export, Aara Khairollahi, Rebecca Adams

SPARK Symposium Presentations

In eukaryotic cells, the transport of mRNA from the nucleus to the cytoplasm is a very regulated process controlled by nuclear pore complexes (NPCs). During stress conditions, such as heat shock, most mRNA export is inhibited in Saccharomyces cerevisiae, yet the transcript for SSA4, a gene responsible for refolding denatured essential proteins, is exported. The mechanism behind this selective export remains unknown. To investigate this, we used CRISPR-Cas9 to generate a reporter strain in which the SSA4 open reading frame was replaced or inserted with green fluorescent protein (GFP). This reporter is designed to produce GFP only under conditions that …

Crispr Transgenic Clytia Hemisphaerica As A Vector For Toxin Delivery In A Zebrafish Melanoma Model, Theodore G. Paz

Theses, Dissertations and Culminating Projects

The jellyfish Clytia hemisphaerica has the potential to be used in cancer therapies with the discovery of potential active toxin target regions to be modified for use. The program Venomix is a Uniprot-based database that was utilized in this experiment to generate likely flagged hit regions using Clytia hemisphaerica CDS files run against its database of terrestrial toxins (Furuno et al., 2003; Macrander et al., 2018). By themselves they are indeterminate as to whether they are active toxin region hits (Macrander et al., 2018). With further analysis such as toxin homology in closely related, annotated marine taxa and accounting for …

Fgf Signaling Is Necessary For Newt Lens Regeneration, Leo Alexander Napoleon

Honors Theses and Capstones

The Iberian ribbed newt Pleurodeles waltl can regenerate the lens by transdifferentiating iris pigmented epithelial (IPE) cells into lens epithelial cells (LECs), but the mechanism by which this occurs remains largely uncharacterized. We aim to mechanistically show an early and critical role for FGF signaling by using small molecules to inhibit FGF receptors and observe the histological and intracellular effects. Two inhibitors were found to completely stall lens regeneration. Cell cycle analysis revealed decreased DNA synthesis and uniformly low but unchanged entry to mitosis under signaling inhibition by staining for EdU incorporation and phospho-histone H3 (pH3), respectively. Western blot revealed …

Bpa: Effects Of The "Plastic Era", Bianca G. Pietrangeli

Student Work

Infographic review of sources of BPA and its impacts on human health with a focus on osteoporosis.

Psr Impacts Chromatin Condensation During Spermatogenesis In Nasonia Vitripennis, Jacqueline R. Solomon

CMC Senior Theses

Paternal Sex Ratio (PSR) is a supernumerary, selfish B chromosome found in the jewel wasp (Nasonia vitripennis). PSR is transmitted strictly paternally to progeny, and when present, it causes paternal genome elimination (PGE) just after fertilization. Due to the haplo-diploid reproduction of N. vitripennis, this PGE event results in all-male broods of progeny, ~90% of which carry and transmit PSR. Thus, PGE is beneficial for PSR’s transmission.  A previous study showed that PSR induces PGE by expressing a gene called haploidizer during spermatogenesis. Although how haploidizer functions in PGE is unknown, this finding suggests two basic models: that (i) the …

Comparing The Differences Of Hsp90Α And Hsp90Β In Native Protein Complex Incorporation, Daryna Serediuk

Honors Theses and Capstones

Epichaperomes are long-lasting, stable assemblies of chaperones, co-chaperones, and associated factors that facilitate cell survival in maladaptive cellular states. Their inhibition has emerged as an attractive therapeutic strategy for the treatment of cancer and neurodegenerative diseases (Rodina et al., 2016). Epichaperomes are hallmarks of robust proliferation in cancer cell populations across many cancer types and are abundantly present in several stem cell varieties, including induced pluripotent stem cells, human embryonic kidney cells, and cancer stem cells (Kishinevsky et al., 2018).

The core protein of the eukaryotic heat shock protein machinery, Heat Shock Protein 90 (Hsp90), is a central chaperone that …

A Framework For Characterizing The Peripheral Immune Isonome Using Long-Read Single-Cell Rna Sequencing And Its Relevance To Neurological Disease, Patricia Hayes Doyle

Theses and Dissertations--Neuroscience

Long-read single-cell RNA sequencing provides an opportunity to understand human health and disease at isoform resolution, revealing cellular diversity and disease mechanisms difficult to resolve with bulk or short-read methodologies.

Using a modified PIPseq workflow and computational pipeline adapted for Oxford Nanopore (ONT) sequencing, we profiled isoform usage across immune cells, integrating marker expression and isoform discovery, generating the largest long-read single-cell dataset of human immune cells from a single individual to date. We identified non-canonical protein-coding variants of GZMB and CD3G enriched in unexpected cell types. We also discovered novel transcripts from CMC1 and LYAR with cell-type-specific signatures that …

Fluorescent Protein Imaging Approaches Uncover Dynamic Subcellular Distribution Of Core Clock Proteins In Neurospora Crassa, Ziyan Wang

Dartmouth College Ph.D Dissertations

Circadian clocks are endogenous self-sustained timekeeping systems that allow organisms to anticipate and adapt to daily environmental cycles. Found in diverse forms of life, these molecular clocks regulate the expression of ~ 40% of the genome in animals, fungi, and plants. In animals and fungi, circadian oscillators are built on transcription-translation feedback loops (TTFLs), in which positive regulators drive the expression of negative regulators which, once synthesized and imported into the nucleus, inhibit their own activators. This precisely regulated negative feedback incorporates multiple steps of delays that are essential for generating ~24-hour rhythms. Through these mechanisms, circadian clocks temporally coordinate …

Investigating The Effects Of Nucleopore Defects On The Cellular Response To Stress In Als/Ftd Ipsc-Derived Neurons, Alicia Christine Collins

Open Access Dissertations

Amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) is a progressive neurodegenerative disease spectrum characterized by motor dysfunction, cognitive decline, and death within a few years of clinical onset. Hallmark features of ALS/FTD include defects in nucleocytoplasmic transport (NCT) and abnormal cytoplasmic mislocalization and aggregation of the RNA-binding protein TDP-43, both of which have been shown to be exasperated by oxidative stress (OS). It remains unclear how these processes are connected and how they collectively contribute to neurodegeneration. To fill this gap of knowledge, we used human embryonic kidney cells, neuroblastoma cells, and induced pluripotent stem cell-derived cortical neurons harboring the ALS/FTD C9ORF72 …

Perfluorooctane Sulfonate (Pfos)-Induced Disruption Of Mitochondrial Activity And Cell Adhesion In Liver Cells, Phuong Dam Nam Tran

Graduate Theses/Dissertations

Perfluorooctane sulfonate (PFOS) is a persistent environmental pollutant associated with potential hepatoxic effects and other health risks. Despite its widespread distribution, the mechanisms underlying its toxicities remain to be fully understood. To investigate PFOS toxicology, my study utilized HepG2 and THLE-2 human hepatic cell models to replicate conditions reflecting PFOS accumulation in the liver. Cell viability, cell stress, and cell death assays were conducted to assess the toxicological influence of the chemical on both cell lines. Total RNA extraction was performed, followed by cDNA sequencing, and RT-qPCR. The XTT viability assay revealed a dose-dependent decrease in number of viable cells …

How Semiflightless Birds Adapt: A Survey From Barú, Costa Rica, Eli P. Laloudakis

Scripps Senior Theses

When we think of birds, we think of flight. Because of this, scientific research often focuses on how birds evolved flight and how their wings function during flight. However, not all birds can fly or fly well, as wings wax and wane on developmental, seasonal, and evolutionary time scales (Dial and Heers 2021). Consequently, rudimentary wings can be found in developing birds, secondarily flightless or semiflightless birds, birds that undergo simultaneous molts, and extinct theropods with “protowings” (structures that preceded fully functional wings). Secondarily flightless and semiflightless birds often evolve where there is no/low predation, abundant year-round food supply, and …

Antiestrogens As Bone Protective Therapeutics For Estrogen Receptor-Positive Breast Cancer In The Presence Of Osteoporosis, Faith E. Parker, Emily K. Zboril, David C. Boyd, Rachel Myrick, J. Chuck Harrell

Undergraduate Research Posters

Breast cancer (BC) is one of the most significant causes of mortality among women and the second leading cause of cancer death in women. The estrogen receptor (ER) is a key oncogenic driver in the majority of breast cancer. ER+ BC is the most common molecular subtype of BC. Management of ER+ breast cancer varies depending on menopausal status. For premenopausal women, the goal is to suppress estradiol production from the ovaries with surgical oophorectomy and/or aromatase inhibitors. In postmenopausal women, endocrine therapy (ET) serves to suppress estradiol production from sources other than the ovaries. During the menopausal transition, estradiol …

Patterns Of Ovarian And Gonadotropin Hormones In Emerging Adult Oral Contraceptive Users, Summer Mcormond

Undergraduate Research Posters

Oral contraceptives (OCs) are often initiated during adolescence and emerging adulthood, a period of continued maturation of the hypothalamic–pituitary–gonadal (HPG) axis. Because hormonal exposure during this window may shape emotional, biological, and reproductive outcomes, it is important to understand the specific formulations young women take and the hormonal profiles these formulations produce. This study characterizes OC formulation features and measured hormone levels in young adult OC users (n = 30).

Ethinyl estradiol (EE) doses ranged from 0.01–0.035 mg (mean = 0.022 mg), with 70% using ≤0.02 mg. Pill regimens included 21/7 packs (83%), 24/4 packs (10%), and 84/7 regimens (3%). …

Exploring Anticholinergic Neurotoxicity: Diphenhydramine's Impact On Neuro-2a Cell Morphology, Expression, And Viability, Jordan B. Mcintyre

Honors Undergraduate Theses

Anticholinergic medications, such as diphenhydramine (commonly known as Benadryl), are increasingly recognized for their association with cognitive impairment and neurodegenerative disease. These medications, which inhibit the action of acetylcholine, a neurotransmitter essential for the formation and utilization of the central and peripheral nervous system, have been implicated in conditions such as dementia and may impact fundamental cellular processes like neurogenesis and cell proliferation. This study investigates the effects of diphenhydramine on neurogenesis when introduced to Neuro-2a cells during differentiation. For all studies cells were plated on coverslips or in 6-well plates with differentiation media containing 0 ng/mL, 50 ng/mL, …

Evaluating Novel Targeted Combination Therapies For Gastrointestinal Cancers, Joseph A. Goode

Graduate Studies Theses and Dissertations 2026

Gastrointestinal (GI) cancers remain among the leading causes of cancer-related mortality worldwide, with therapeutic resistance continuing to limit the effectiveness of current treatments. Three complementary studies were conducted to identify therapeutic vulnerabilities and evaluate novel combination strategies in pancreatic ductal adenocarcinoma (PDAC) and colorectal cancer (CRC).  First, dual inhibition of fibroblast growth factor receptor 4 (FGFR4) and phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling was investigated in PDAC models. A combination of targeted drug treatments reduced viability, clonogenic survival, migration, and suppressed signaling pathways involved in translational control. This supported a functional interaction between FGFR4 and PI3K-mTOR co-activation in …

The Importance Of The Proline Residue In The Ldiapa Motif Of Cholera Toxin, Akash Bharathan

Honors Undergraduate Theses

Cholera is currently on its seventh global pandemic, disproportionately affecting developing countries. Vibrio cholerae, the bacterial etiologic agent, is able to cause infection by adhering to intestinal epithelial cells and secreting cholera toxin (CT), an AB-type exotoxin that dysregulates signaling pathways. Previous research by the Teter lab has shown that Hsp90, a host cytosolic chaperone, is required for CT to enter the cytosol where it produces toxic effects. Hsp90 binds to CT at two specific motifs, RPPDEI and LDIAPA. The prolines in the RPPDEI motif are essential for binding, but the proline in the LDIAPA has yet to be …

Targeted And Screening Based Approaches To Analyze Drm Transcriptional Repressor Complex Activity In Caenorhabditis Elegans, Emily Washeleski

Dissertations, Master's Theses and Master's Reports

The molecular machinery that control the eukaryotic cell cycle, specifically the processes that mediate the switch between cellular division or quiescence, are essential for cellular and organismal viability. However, how the same machinery integrates with developmental or differentiation programs is less well understood. In Caenorhabditis elegans, the 8-subunit DRM complex (for Dp, Rb and MuvB), whose subunits belong to the Synthetic Mulitivulva (SynMuv) B class genes, is a central regulator of the cell cycle but also prevents inappropriate cell fate specification. The conserved mammalian DREAM complex (for Dp, Rb, E2F, And MuvB) is best known as a transcriptional repressor …

Developing A Tool To Measure Resistance To Sustainable Food Choices: A Pilot Study In Ireland And The Netherlands, Kate Flanagan, Bart Sinteur, Patricia J. Bulsing, John M. Kearney

SURE Journal: Science Undergraduate Research Experience Journal

Consumer uptake of a sustainable diet is critical for addressing environmental challenges and promoting public health. Understanding why consumers resist adopting sustainable eating habits can inform targeted interventions and policies. This pilot study examines whether a newly developed scale can effectively detect consumer resistance to a sustainable diet. Currently, there is a lack of research on a tool to measure consumer resistance to a sustainable diet, highlighting the need for a reliable instrument.

The aim of this study is to develop a scale, based on existing literature, to measure consumer resistance to a sustainable diet. Additionally, the study aims to …

Editorial-Sure Journal Volume 7, Issue 2, Geraldine M. Dowling, Eva Campion, Sinead Loughran, Ariane Perez-Gavilan, Josephine Treacy

SURE Journal: Science Undergraduate Research Experience Journal

No abstract provided.

Development Of Self-Assembled Polymeric Polyplexes For Microrna Delivery: Toward Treatment Of Alcohol-Associated Liver Disease, Marjina Akter Kalpana

Theses & Dissertations

Self-assembled polymeric polyplexes have the potential to serve as an RNA interference (RNAi) delivery platform for the combined inhibition of CXCR4 and miR-155 in the treatment of alcohol-associated liver disease (AALD). A central challenge in RNA delivery is balancing the extracellular stability of polyplexes, cellular uptake, and intracellular release of RNA cargo. We developed polymeric polyplexes using the CXCR4-antagonist polymer PAMD, designed to target CXCR4 on activated hepatic stellate cells (HSCs) and deliver therapeutic miRNA to activated Kupffer cells (KCs) in fibrotic liver. We improved the polyplexes by cholesterol modification of PAMD and by PEGylation of PAMD-Ch. The cholesterol modification …

Functionality Of The Ryanodine Receptor Type 1 (Ryr1) In The Development Of Malignant Hyperthermia (Mh), Cesar Medina, Joshua Owens

Student Scholar Symposium

Malignant Hyperthermia (MH) is a rare but potentially lethal pharmacogenetic disorder, affecting roughly 1 in 30,000 children and 1 in 100,000 adults undergoing surgery. MH can be triggered by agents used for general anesthesia. These may include volatile anesthetics such as sevoflurane, isoflurane, desflurane, halothane or depolarizing neuromuscular blockers such as succinylcholine. Upon administration of a trigger, an MH susceptible (MHS) patient can develop a hypermetabolic state during the intraoperative or postoperative periods. If not treated quickly, an MH episode could result in organ dysfunction or death. The primary mechanisms involved in the development of an MH crisis include the …

Context Dependent Regulation Of Dicer Function During Oocyte-To-Embryo Transition, Nick A. Newkirk

Dissertations and Theses (Open Access)

Over two decades ago, Dicer was discovered as the primary enzyme responsible for the generation of small RNAs known as the microRNAs (miRNAs) and short interfering RNAs (siRNAs). Spatiotemporal regulation of Dicer-dependent small-RNA biogenesis affects many aspects of biology, including aging, disease progression, fertility, and cancer. Interestingly, a distinct population of Dicer-dependent small RNAs, known as the endogenous siRNAs (endo-siRNAs), are uniquely abundant in the germ cells and gametes, and are critical for normal fertility. Despite their function regulating new life, the mechanisms controlling their biogenesis and subsequent germ cell functions remain poorly defined. Work to parse these mechanisms in …

A Molecular Mechanism Of Epithelial To Mesenchymal Transition (Emt): An Evidence Based Lesson Applying Molecular Biology Through The Lens Of Cancer, Sophie Hasson, Melissa Rowland-Goldsmith

Open Educational Resources

This lesson aims to strengthen students’ critical thinking and molecular biology data analysis skills as well as their understanding of concepts related to the hallmark of cancer: tissue invasion and metastasis. Students begin by learning about the invasion of cancer cells, Epithelial-Mesenchymal Transition (EMT), and an important protein involved in EMT: E-cadherin. They then apply molecular biology knowledge to analyze data from multiple papers to infer the relationship between Snail and E-cadherin in different types of cancers. Next, they continue to interpret data from many papers to determine that a repressor transcription factor is present during EMT in cancer cells …