Molecular Biology Commons^™

The Structure Of The Drp1 Lattice On Membrane, Kristy Rochon, Anelise N. Hutson, Jason A. Mears

Faculty Scholarship

Mitochondrial health relies on the membrane fission mediated by dynamin-related protein 1 (Drp1). Previous structural studies of Drp1 on remodeled membranes were hampered by heterogeneity, leaving a critical gap in the understanding of the mitochondrial fission mechanisms. Here we present a cryo-electron microscopy structure of full-length human Drp1 decorated on membrane tubules. Using the reconstruction of average subtracted tubular regions (RASTR) technique, we report that Drp1 forms a locally ordered lattice along the tubule without global helical symmetry. The filaments in the lattice are similar to dynamin rungs with conserved stalk interactions. Adjacent filaments are connected by GTPase domain interactions …

Analysis Of Synaptotagmin Isoforms In Lßt2 Gonadotrophs, Caitlin Vahl

Undergraduate Theses, Capstones, and Recitals

The anterior pituitary is comprised of five cell types which secrete regulatory hormones into the bloodstream. Specifically, gonadotrophs synthesize and release sex hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in response to gonadotropin-releasing hormone (GnRH). GnRH signals from the hypothalamus regulate the differential secretion of LH and FSH from the anterior pituitary. Exocytosis of FSH and LH from dense core vesicles (DCVs) occurs in response to an intracellular calcium signal, sensed by the synaptotagmins proteins. Various isoforms of synaptotagmins exist and each isoform has varying affinity for calcium, causing calcium-regulated exocytosis to be finely controlled. Because LH and FSH …

The Anticancer Activity Of Novel Chromene Derivatives Against Colorectal Cancer Cells, Rym Magramane

Thesis/ Dissertation Defenses

Colorectal cancer (CRC) stands as the third most common cancer globally, accounting for nearly 10% of all newly diagnosed cancer cases. In the UAE, CRC was ranked as the third most frequently diagnosed malignancy, and the leading cause of cancer-associated deaths in 2023. Standard CRC treatment strategies include surgical resection, chemotherapy, immunotherapy, targeted therapy, or a combination of all, depending on the cancer stage and molecular profile. Despite these interventions, disease recurrence is experienced by a considerable number of cancer patients. Hence, there is an urgent need to develop novel alternative treatments to overcome poor prognosis. Recently, cancer research has …

Role Of Gut-Liver-Brain Axis In Neuropsychiatric Symptoms Of Parkinson’S Disease, Raveena Dhanani Ratnayake

Student Theses and Dissertations

Neuropsychiatric symptoms (NPS), such as depression, and anxiety, and mild cognitive impairment (MCI), often precede motor symptoms in Parkinson’s disease (PD), highlighting the need for early biomarkers and mechanistic insights. Gut-microbiome-related metabolites, including secondary bile acids, influence lipid homeostasis and mitochondrial function, impacting neuropsychiatric and neurodegenerative disorders. This study examines metabolic alterations in PD, focusing on lipid metabolism, bile acids, acylcarnitine, and amino acids. Our findings showed significant changes in lipid metabolism, transsulfuration pathway, bile acids, acylcarnitine, and amino acids in PD severity and NPS. Specific lipid subclasses were linked to NPS, cognitive impairment, and motor impairment. Given the limited …

Why Acromegaly Dies: A Systematic Review, Isam Noori Salman, Safaa Ehssan Atta, Baydaa Ahmed Abed, Noor Ulhuda G. Mohammed

Maaen Journal for Medical Sciences

Acromegaly is a rare endocrine clinical syndrome characterized by long-term elevated production of growth hormone (GH) due to a pituitary adenoma tumor. The main problem of acromegaly patients (AC-PTs) is prolonged elevated GH concentration, which leads to increased insulin-like growth factor 1 (IGF-1) production, causing the characteristic tissue and bone overgrowth. The appearance of diabetes in AC-PTs was linked with the high risks of cardiovascular morbidity, indicating that individuals with both conditions face heightened health challenges. Acromegaly typically has a higher cancer incidence rather than the general population. Without early diagnosis and effective treatment, excess GH can have widespread systemic …

Lighting Up The Cell: Developing A Luminescent Lanthanide Probe For Detecting Rnas, Jonathan Savell

Honors Projects

An anion detecting luminescent probe, Tb:DO2A-Cs124, was repurposed for use in RNA imaging. Potential RNA aptamers were identified for the molecule using Capture-SELEX and MinION sequencing. Fluorimetry data revealed these aptamers did not allow for the probe to luminesce in the presence of target RNAs due to adenosine monophosphate’s ability to quench the emission signal.

A Hormone-Dependent Trna Half Promotes Cell Cycle Progression Via Destabilization Of P21 Mrna, Takuya Kawamura, Megumi Shigematsu, Yohei Kirino

Department of Biochemistry and Molecular Biology Faculty Papers

tRNA halves are among the most abundant short non-coding RNAs in the cellular transcriptome. Here we report that in androgen receptor-positive LNCaP prostate cancer cells, the hormone-dependent 5'-tRNALysCUU half promoted cell proliferation by facilitating cell cycle progression. Global mRNA profiling upon the 5'-tRNALysCUU half depletion revealed that the mRNA of p21, a negative regulator of the cell cycle, is post-transcriptionally destabilized via a 5'-tRNALysCUU half-driven mechanism. YBX1, identified as a protein interacting with 5'-tRNALysCUU half in the cytosol, was shown to stabilize p21 mRNA. Specific sequences resembling the 5'-tRNALysCUU half, located in the 3'-UTR of p21 mRNA and termed LL588, …

Breaking The Rules: Post-Translational Modifications And Proteome Dynamics During Anoxia, Chelsea Jordan Hughes

Dissertations and Theses

Most organisms are ill-equipped to survive anoxia, but some organisms have developed molecular strategies to mitigate the cellular stressors associated with a lack of oxygen. While it is established that anoxic survival is contingent on metabolic suppression, it is unclear what mechanisms support this change in gene expression. Gene expression is regulated by a variety of mechanisms within the cell, including alteration of chromatin structure through histone modifications and protein modifications which contribute to the ever-changing proteomic landscape of the cell. Protein modifications such as ubiquitylation can lead to the degradation of proteins, while modifications to transcription factors can change …

Elucidating The Roles Of Eukaryotic Initiation Factors Involved In Dap5 Mediated Translation, Jacob Nk Quartey

Dissertations, Theses, and Capstone Projects

Translation initiation in eukaryotes is a highly regulated process essential for accurate protein synthesis. It is a dynamic process that involves a complex interplay between messenger RNAs (mRNAs), ribosomal subunits, and a host of initiation factors, ensuring precise start codon selection and the subsequent assembly of the translation machinery. This process has well been known to be mediated by the eukaryotic Initiation Factor (eIF4F), which consists of the cap binding protein eIF4E, the scaffolding protein eIF4GI, and the helicase factor eIF4A.The recognition and binding of eIF4E to the m⁷G cap structure of the mRNA is essential for the …

Investigating A Link Between Dna Repair And Dna Replication In Escherichia Coli Using A Bacterial Two-Hybrid System, Lo Cooper

University Honors Theses

Cells rely on nucleotide excision repair (NER) to remove bulky DNA lesions, such as those caused by UV light. In Escherichia coli, NER involves the UvrABC complex, and includes two main pathways, global genomic repair and transcription-coupled repair (TCR). While TCR, which preferentially removes lesions that block RNA polymerase on the transcribed strand of active genes, is well studied, less is known about whether a similar coupling between repair proteins and replisomes blocked by damaged DNA exists. Such a process has been suggested by a high throughput interactome study, using the replisome subunit HolC as bait and the damage …

Kinetic Analysis Reveals T6a-Protein Specificity For T6a And Hn6a Trna Modifications, Cassandra Mae Harker

University Honors Theses

Transfer RNA (tRNA) is essential for accurate translation of genetic information and plays a role in cellular processes such as lipid aminoacylation and bacterial conjugation. Base modifications help tRNA fold correctly and function properly. An important base modification, N6-threonylcarbamoyladenosine (t6A) occurs at position A37 in the anticodon-stem-loop of tRNA. This modification is crucial for decoding ANN codons. Interestingly, an Archeal organism, Methanocaldococcus jannaschii, can have either t6A and hydroxynorvalylcarbamoyl-6- adenosine (hn6A) modification at the same position on tRNAs. As Tsa proteins catalyze the formation of both t6A and hn6A modifications, this raises the question of whether discrimination between these …

Genetic Factors Of Campylobacter Jejuni Required For Its Interactions With Free-Living Amoeba, Deepti Pranay Samarth, Asim Z. Abbasi, Young Min Kwon

Poultry Science Faculty Publications and Presentations

Acanthamoeba, a free-living amoeba ubiquitous in environmental water, has been considered as the environmental reservoir of certain bacterial pathogens, including Campylobacter jejuni, an intracellular human pathogen causing self-limiting gastroenteritis. Acanthamoeba-C. jejuni interaction mechanisms may help clarify how the otherwise fastidious bacterium C. jejuni survives in environmental waters. In this study, we constructed single deletion mutants of C. jejuni strain 81-176 for the 10 selected genes (motAB, ciaB, kpsE, virB11, cheY, flaAB, cstII, docB, sodB, and cadF) previously shown to be important for the interaction (invasion and intracellular survival) of C. jejuni with mammalian hosts. We used a modified gentamicin protection …

Characterization Of Sars-Cov-2 Replication And Transcription Complexes Via Structural And Evolutionary Approaches, Amelie Ghirardo, Ben Shabatian, Avishai Aghelian, Kyle Tau, Eleonora Gianti

Undergraduate Research

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused around 700M cases and over 7M COVID-19-related deaths recorded worldwide (World Health Organization, March 2025). Aiming to effectively combat this and other disease-causing Coronaviruses (CoV), unprecedented research efforts led to the development of new vaccines and antiviral therapies. Due to emergence of variants of concern (VOCs) with increased transmissibility, immune evasion from vaccination, and potential to resist the available treatments, SARS-CoV-2 continues to represent a major threat to global health. Hence, there is a pressing need to discover new antivirals with broad-spectrum efficacy against multiple SARS-CoV-2 variants and related CoVs. This project …

Ion-Dna Interactions As A Key Determinant Of Uracil Dna Glycosylase Activity., Sharon N Greenwood, Alexis N Dispensa, Matthew Wang, Justin R Bauer, Timothy D Vaden, Zhiwei Liu, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Because of their ubiquitous presence, ions interact with numerous macromolecules in the cell and affect critical biological processes. Here, we discuss how cations including Mg²⁺ alter the enzymatic activity of a DNA glycosylase by tuning its affinity for DNA. The response of uracil DNA glycosylase (UNG2) to Mg²⁺ ions in solution is biphasic and paradoxical, where low concentrations of the ion stimulate the enzyme, but high concentrations inhibit the enzyme. We analyzed this phenomenon by modeling experimental data with a statistical framework that we empirically derived to understand molecular systems that display biphasic behaviors. Parameters from our statistical …

Generation Of A Transgenic Vector For The Purpose Of Transforming Charcoal Rot Resistance Into Soybeans (Glycine Max), John M. Bear Jr

Electronic Theses & Dissertations

Charcoal rot, caused by Macrophomina phaseolina, is among the most devastating fungal pathogens affecting G. max, particularly in drought-susceptible regions such as the midwestern United States. Traditional agricultural practices have included crop rotation and irrigation, which have proved ineffective or economically unfeasible. Charcoal rot infects over 500 other species of plants and can overwinter as dormant sclerotia which can germinate once soybeans are re-planted and infect young plants. As a result, transgenic solutions have offered a promising alternative for the development of disease-resistant soybeans. This thesis documents the construction of a transgenic vector to express BOZO, a …

Assessing The Effects Of Streptozotocin-Induced Hyperglycemia On Amyloid Beta Accumulation And Cognitive Behavior In A Mouse Model Of Alzheimer’S Disease-Related Pathology, Andrew Adonay Ortiz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer’s disease (AD) is an irreversible and devastating neurodegenerative disease characterized by progressive synaptic, dendritic, glial, and neuronal loss, collectively leading to impairments in learning, memory, and deterioration of cognitive and behavioral functions. AD is the most common form of dementia accounting for 60-80% of all cases. AD affects approximately 7 million Americans and is the 6th leading cause of death in the US. Furthermore, by 2050, the US is projected to spend over $1.1 trillion on AD-related treatments. Pathological hallmarks of AD include beta-amyloid (Aβ) plaques, intracellular neurofibrillary tangles (NFTs), and chronic neuroinflammation, which can promote and exacerbate both …

Detection And Quantification Of Total Airborne Fungi And Coccidioides Species In Environmental Samples, Theresa T. Roehr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fungal exposure can cause acute and chronic illnesses or exacerbate existing illnesses. Some fungi are opportunistic pathogens and can lead to serious systemic fungal infections. In 2020, more than 150 million cases of severe fungal infections were reported globally resulting in an estimated 1.7 million deaths. Coccidioidomycosis, or Valley fever, is classified as a serious fungal infection caused by the fungi Coccidioides immitis and C. posadasii. These particular fungi are prevalent in the soil of the Southwestern United States, including Las Vegas, Nevada. In 2024, there were a total of 269 cases of Valley fever reported in Nevada, and …

Mannose: The Hands Of Fate – Overexpressing A Pinus Taeda Hemicellulose Biosynthesis Gene In Populus Tremula × Alba Leads To Increased Height And A Modified Cell Wall Sugar Profile, Joseph Baxter Colbert

Dissertations - ALL

Lignocellulosic biomass as an input for biofuel generation has gained popularity in recent decades due to attainable feedstock ubiquity and an anatomical propensity to fix and sequester carbon. A major challenge facing the integration of such feedstocks is the presence of recalcitrant polymers that are extant in their cell walls, namely lignin and various hemicellulose species. Many studies have illustrated methods in which cell wall modification through genetic means has produced phenotypic improvements with regard to biomaterial generation, though to this point, none have overexpressed exogenous hemicellulose genes to shift the composition of the Populus tremula × alba cell walls. …

Drivers And Mechanisms Of Golgi Fragmentation As A Modulator Of Disease, Amanda Macke

Theses & Dissertations

The Golgi apparatus plays a pivotal role in post-translational modification, trafficking, and secretion of proteins, ensuring proper cellular function. As a result, its fragmentation has been implicated in multiple pathological conditions, including alcohol-induced liver injury and prostate cancer (PCa). Despite its known impact on cellular homeostasis, the molecular mechanisms governing Golgi fragmentation remain to be clarified. Additionally, we have only just begun to understand the vast consequences of Golgi disorganization on disease progression.

This dissertation investigates the drivers and mechanisms of Golgi fragmentation, with a focus on its role as a modulator of disease. Using both in vitro and in …

Understanding The Role Of Sabp2-Interacting Proteins Sip432: A Premnaspirodiene Oxygenase Enzyme In Stress Signaling, Cristiana F. Martinez

Undergraduate Honors Theses

This study focuses on the characterization of a SABP2-interacting protein (SIP)-432. SIP432 is a putative premnaspirodiene oxygenase-like P450 enzyme. Premnaspirodiene is a 15-carbon compound that can be converted into antimicrobial compounds by a hydroxylation reaction. The interaction of SIP432 with SABP2, a critical component of salicylic acid-mediated plant immunity, implies a role for SIP432 in plant stress signaling. This study uses the T-DNA knockout mutant of Arabidopsis thaliana SIP432 (homolog of NtSIP432) to help understand its role in abiotic and biotic stress responses. Plants were subjected to abiotic and biotic stress to understand their role in stress response pathways. Gene …