Molecular Genetics Commons^™

Gonadal Absence Of Ceh-22: Degradation Of Ceh-22 In The Gonads Of Caenorhabditis Elegans, Andreya C. White

Undergraduate Theses

The reproductive system of hermaphrodite Caenorhabditis elegans (C. elegans) comprises two gonadal arms, each with a terminating distal tip cell (DTC), connected by a common uterus. The DTC has two functions: leader and niche. In C. elegans, ceh-22/nkx2,5 has been found to work together with Wnt signaling to determine the fates of the DTC (Lam et al., 2006). This is an indication that ceh-22 aids in the specification of DTCs. Our research aims to determine the specific function of ceh-22 in the gonad of both male and hermaphrodite C. elegans. This will be accomplished by observing …

A Natural Short Sleep Mutation Promotes Longevity Through Mitochondrial Respiration In Drosophila, Pritika Pandey

LSU Doctoral Dissertations

Aging is an irreversible process characterized by progressive physiological decline and an increased risk of metabolic disorders, cognitive impairment, cardiovascular diseases, and neurodegeneration. Disruptions to the circadian clock—whether due to genetic mutations or behavioral factors—accelerate aging and age-related pathologies, highlighting a strong link between circadian regulation and longevity. However, certain individuals harbor a dec2^P384R mutation, which enables natural short sleep without the detrimental effects of chronic sleep deprivation. This suggests that these individuals have evolved adaptations that activate pro-health pathways, allowing them to function optimally with reduced sleep. To investigate the genetic mechanisms underlying these changes, we developed a …

Robust Sex Determination In The Caenorhabditis Nigoni Germ Line, Jonathan P Harbin, Yongquan Shen, Shin-Yi Lin, Kevin Kemper, Eric S Haag, Erich M Schwarz, Ronald E Ellis

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Sexual characteristics and reproductive systems are dynamic traits in many taxa, but the developmental modifications that allow change and innovation are largely unknown. A leading model for this process is the evolution of self-fertile hermaphrodites from male/female ancestors. However, these studies require direct analysis of sex-determination in male/female species, as well as in the hermaphroditic species that are related to them. In Caenorhabditis nematodes this has only become possible recently, with the discovery of new species. Here, we use gene editing to characterize major sex-determination genes in C. nigoni, a sister to the widely studied hermaphroditic species C. briggsae. These …

Missense Mutation Of Msh6 Leucine 696 Has No Apparent Effect On The Dna Mismatch Repair Process, Razan H. Hammad, Rafia Rashid, Essence Tarrence, Christopher Bolden, Joanna E. Haye-Bertolozzi

XULAneXUS

Lynch Syndrome and Constitutional Mismatch Repair Deficiency are human diseases implicated in mutations of DNA mismatch repair (MMR) genes. This experiment tested a mutation of an MMR gene, MSH6, and evaluated how the mutation affected overall MMR effectiveness. Using the yeast Saccharomyces cerevisiae, we performed the CAN1 forward mutation assay to study msh6-L696F and its implications in the MMR process. We hypothesized that there would be a significant change in molecular function in the Msh6 protein in the presence of this mutation. Bioinformatic tools predicted that this amino acid change would have deleterious effects on MMR function. However, …

Life After Death: Investigating The Resistance And Recovery Of Fungal Communities To Foundation Tree Mortality, Jessie F. Marlenee

Biology ETDs

Tree mortality can have cascading effects on the composition and resilience of interacting fungal communities. Yet, little is known about the impact tree mortality, distinct from abiotic drivers (i.e., drought), has on these communities. This dissertation focuses on the resilience of fungal communities to experimental tree mortality in a piñon-juniper woodland. In chapter one, I found that piñon mortality reduced piñon fine root biomass and piñon mycorrhizal fungal diversity, whereas juniper mycorrhizal fungi were unaffected by juniper mortality. In chapter two, I revealed that piñon mortality altered the composition and spatial structure of mycorrhizal and saprotrophic fungi in the soil, …

Hierarchical Lineage Tracing To Unravel Mechanisms Of Cancer Treatment Resistance, Rachel Danielle Saxe

Dartmouth College Ph.D Dissertations

Cancer cells adapt to treatment, leading to the emergence of clones that are more aggressive and resistant to anti-cancer therapies. We have a limited understanding of the development of treatment resistance as we lack technologies to map the evolution of cancer under the selective pressure of treatment. To address this, we developed a hierarchical, dynamic lineage tracing method called FLARE (Following Lineage Adaptation and Resistance Evolution). We use this technique to track the progression of acute myeloid leukemia (AML) cell lines through exposure to Cytarabine (AraC), a front-line treatment in AML, in vitro and in vivo. We map distinct cellular …

Focal Adhesion Genes And Proteins Are Differentially Expressed Across Cell Types In Down Syndrome, Brian Yoon

Senior Theses

Down syndrome (DS), caused by an extra copy of chromosome 21, leads to widespread gene expression changes through mechanisms such as transcriptional dysregulation and altered protein interactions. These disruptions contribute to a range of clinical features, including impaired wound healing, immune dysfunction, and neurodevelopmental abnormalities. This study focused on how DS affects fibroblast morphology and motility—processes critical for tissue repair and brain development. Using quantitative immunocytochemistry and image analysis, we found that DS fibroblasts displayed a broader, less polarized shape, with increased cell perimeter and reduced aspect ratio. However, levels of key adhesion proteins like vinculin, FAK, and β-actin were …

Investigating Sk-3 Based Spore Killing In Neurospora Crassa Through Deletion Analysis Of Dna Intervals I383 And I394, Paulina Paulikas

Senior Theses – Biological Sciences

Neurospora fungi are found around the world. The species N. crassa is a popular model for use in genetics research. N. crassa produces sexual spores, called ascospores, during mating between strains of opposite mating types. N. crassa also produces spore sacs called asci, and each ascus typically contains eight viable ascospores. However, some Neurospora fungi carry selfish genetic elements called Spore killers, and when a strain carrying a Spore killer mates with a spore killing-susceptible strain, asci contain four black viable ascospores and four white inviable ascospores. In this project, I investigated a Spore killer called Sk-3. To act as …

Examining The Mechanism Of Spore Sacs Undergoing Sk-3-Based Spore Killing After Deletion Of Neurospora Crassa Dna Intervals I382 And I400, Makenna Klann

Senior Theses – Biological Sciences

Neurospora crassa is a well-known model organism for studying eukaryotic genetics, particularly non-Mendelian inheritance mechanisms such as meiotic drive. In N. crassa, meiotic drive can be observed in fungal spore killing, where Spore killer-3 (Sk-3) is a selfish genetic element transmitted to offspring through spore killing. Sk-3 is thought to contain two principal components: a killer (poison) gene and a resistance (antidote) gene. While the resistance gene (rsk) has been identified, the killer gene remains unknown. Building on previous research that identified a 1.3 kb DNA interval (i350) essential for Sk-3-based spore killing, I …

Determining The Effects That Deletion Of I386 And I408 Have On Sk-3-Type Spore Killing, Kole Damkoehler

Senior Theses – Biological Sciences

Neurospora crassa is a genus of fungus that exhibits a phenomenon called Sk-3 spore killing. Sk-3 spore killing occurs when an Sk-3 killer strain mates with an Sk-3 sensitive strain, and it results in the death of half of the offspring. A DNA interval called i350, located on N. crassa Chromosome III, has previously been identified as critical for spore killing. Here, to obtain a more detailed understanding of this DNA interval, the effects of the deletion of related DNA intervals i386 and i408 on spore killing has been studied. Deletion of i386 resulted in no disruption of spore …

Crispr-Induced Mutagenesis Of Arabidopsis Thaliana Gene Apetala3, Hazel Frans, Tara Phelps-Durr

SACAD: Scholarly Activities

This project aims to create CRISPR-CAS9 mutations in the APETELA3 (AP3) gene of the model plant Arabidopsis thaliana. AP3 is a class B gene critical to the petal and stamen development of Arabidopsis flowers. AP3 is defined in a MADS domain, which binds directly to DNA and may be responsible for the expression of the CaRG-box genes. AP3 works in conjunction with PISTILLATA (PI), AGAMOUS (AG), APETALA1 (AP1), and SEPALLATA (SEP) genes to specify the development in the second and third whorls of the flower. While several alleles of AP3 already exist, these alleles are strong alleles that knockout gene …

A Study To Identify The Causal Rare Genetic Variants In Primary Open And Closed Angle Glaucoma, Pseudoexfoliation Syndrome, And Associated Glaucoma, Suganya K

Theses and Dissertations

BACKGROUND: Glaucoma is the second most common cause of blindness globally typically diagnosed with a triad of clinical symptoms of increased intraocular pressure (IOP) with associated optic disc, optic nerve head (ONH) changes, and visual field defects. Genetic and environmental factors are some of the strong aetiology factors for glaucoma and identification of these factors has a potential implication in the management of the disease and its outcome. There is a paradigm shift towards understanding the genetics of glaucoma, wherein the variants in the nuclear, mitochondrial genome and other regulatory regions are being identified as contributing risk factors.

METHODOLOGY AND …

The Design, Construction, And Testing Of Mrna Vaccine Against Equine Herpes Virus, Bhawana Devkota

LSU Master's Theses

Equine Herpesvirus-1 (EHV 1) is a worldwide significant pathogen that causes respiratory illness, abortion, and neurological disorders in equine. Current vaccines, including live attenuated, inactivated, and subunit platforms, do not prevent viral latency, mucosal shedding, or cross-strain immunity, requiring alternative approaches. To address these gaps, this project explores the design, synthesis, and in vitro testing of an mRNA vaccine targeting immunogenic EHV 1 glycoprotein (gB, gC, gD, gG, and gM). Epitopes were computationally predicted using the Immune Epitope Database (IEDB), codon-optimized for Bos taurus, and cloned into pUCIDT vectors using SP6/T7 promoters. In vitro transcription (IVT) used nucleotide modifications …

Cloning And Expression Of Scamp3 In Escherichia Coli Bl21(De3) With In Silico Sequence-Based Cancer Epitopes Prediction, Selly Setiati Rajagukguk, Sabar Pambudi, Astari Dwiranti, Doddy Irawan Setyo Utomo, Anom Bowolaksono

Makara Journal of Science

Secretory carrier membrane protein 3 (SCAMP3) is a crucial membrane protein involved in intracellular vesicle traffick-ing and exocytosis. The SCAMP3 expression has been observed in diverse cancer types, such as melanoma, glioma, hepatocellular and breast cancer. Increased SCAMP3 expression has been reported in certain cancer cells relative to that in normal cells, suggesting the potential role of SCAMP3 in cancer development or progression. In this study, we successfully cloned and expressed SCAMP3 in Escherichia coli strain BL21(DE3). SCAMP3 was amplified and insert-ed directionally into the prokaryotic expression vector pET21d(+). The transformation of recombinant plasmid into E. coli BL21(DE3) cells were …

Emerging Technologies For Forensic Genetic Identification, Lilly Llanos

Senior Honors Theses

There are many new innovations in forensic science that are being developed for the identification of biological evidence. These techniques include next-generation DNA sequencing, DNA phenotyping, and forensic genetic genealogy. This thesis will explore each, as well as newer applications of proteomics. The methodologies, reliability, practicality of cost and training, moral implications, and past research of each will be discussed. Finally, some ideas for future research and steps to drive growth and greater understanding will be suggested. This will encourage further innovations and the increased acceptance of forensic evidence in court. Each method was found to have both advantages and …

Cargo Hitchhiking Autophagy - A Hybrid Autophagy Pathway Utilized In Yeast, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Macroautophagy is a catabolic process that maintains cellular homeostasis by recycling intracellular material through the use of double-membrane vesicles called autophagosomes. In turn, autophagosomes fuse with vacuoles (in yeast and plants) or lysosomes (in metazoans), where resident hydrolases degrade the cargo. Given the conservation of autophagy,

Microbial Source Tracking Protocols For Differentiation Of Fecal Bacteria From Cow, Deer, And Horse, Nika Shams, Michael Beach

Symposium of Student Scholars

Microbial source tracking (MST) attempts to identify specific animal sources of fecal contamination in the environment. While traditional fecal coliform enumeration can give a general measure of contamination, the specificity imparted by modern MST provides a more informative assessment of contaminants and their likelihood to affect human health outcomes.

We have been developing an MST system that detects DNA biomarkers from the gram-negative bacterial genus Bacteroides and the family Lachnospiraceae. They are strict anaerobes found in large quantities in the intestines of animals. Unlike E. coli or Enterococci, host-specific strains of Bacteroides and Lachnospiraceae exist. To this end, we …

Identification Of Novel Argonaute Proteins Using A Metagenomic Mining Approach, Lobna Abdallah Ghonaim

Theses and Dissertations

Gene editing is one of the most promising tools in science. It enables precise modifications of an organism's genetic material. Metagenomics is considered a powerful tool that unlocks the broad genetic potential found in uncultured microbial communities. Exploring the genetic diversity of uncultured microbial communities helps identify novel functional proteins with unique properties and make the best use of these diverse microbial ecosystems.

We developed and employed a metagenomic-based approach to mine more than 1000 metagenomes for prokaryotic argonaute proteins (pAgos), a potential gene editing machinery encoded in bacterial and archaeal genomes. Our workflow involved strict quality control, sequence assembly, …

Extracellular Vesicles Released By All Patients Contain Hne-Adducted Proteins: Implications Of Collateral Damage., Jenni Ho, Suriyan Sukati, Tamara Taylor, Sherry Carter, Brittany Fuller, Amy Marmo, Caryn Sorge, John D'Orazio, D Allan Butterfield, Subbarao Bondada, Heidi Weiss, Daret K St Clair, Luksana Chaiswing

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Off-target neuronal injury is a serious side-effect observed in cancer survivors. It has previously been shown that pediatric acute lymphoblastic leukemia (ALL) survivors have a decline in neurocognition compared to healthy age-matched counterparts. Elevated oxidative stress has been documented to be a mediator in off-target tissue damage in cancer survivors. Early detection of oxidative stress markers may provide an opportunity to prevent off-target tissue damage. Extracellular vesicles (EVs) have surfaced as a potential diagnostic tool due to molecular cargo they contain. We investigated the potential for EVs to be a sensitive indicator of oxidative stress and off-target tissue damage by …

The Role Of Secondary And Tertiary Structure In The Cap-Independent Translation Of Fgf-9 And Hif-1-Alpha, Amanda Michelle Whittaker

Dissertations, Theses, and Capstone Projects

Under normoxic conditions, eukaryotes initiate translation of RNA through eIF4E recognition of the 5’ cap. However, under cellular stress, eukaryotic translation must be initiated through a 4E-independent, or “cap-independent” mechanism, involving eukaryotic initiation factor 4G (eIF4G) binding directly to the 5’ untranslated regions (5’ UTR) of the RNA. eIF4G binding then recruits the ribosome to the transcript. While this mechanism is useful for translation of apoptotic transcripts and transcripts involved in cell survival, cap-independent translation is also utilized by oncogenic RNA for tumorigenesis. Previous work by our lab and others has categorized this recruitment and initiation mechanism as either internal-ribosome-entry-site …

Mitochondrial Mrna And The Small Subunit Rrna In Budding Yeasts Undergo 3'-End Processing At Conserved Species-Specific Elements, Michael Anikin, Michael F Henry, Viktoria Hodorova, Hristo B Houbaviy, Jozef Nosek, Dimitri G Pestov, Dmitriy A Markov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Respiration in eukaryotes depends on mitochondrial protein synthesis, which is performed by organelle-specific ribosomes translating organelle-encoded mRNAs. Although RNA maturation and stability are central events controlling mitochondrial gene expression, many of the molecular details in this pathway remain elusive. These include

Investigating The Thermodynamic Properties Of Fat10 And Fat10ylated Proteins, Aravind R

Theses and Dissertations

Degradation of proteins by the proteasome is crucial in regulating protein levels in the cell. Post-translational modifications, such as ubiquitylation and Fat10ylation, trigger proteasomal degradation of the substrate proteins. While ubiquitylation orchestrates multiple cellular processes, Fat10ylation is primarily involved in the inflammatory response. Unlike ubiquitin, recycled upon substrate degradation, Fat10 is degraded along with its substrate. Although the thermodynamic properties of the substrate are critical for effective proteasomal degradation, they remain poorly understood for the Fat10-proteasome pathway.

Here, we demonstrate that Fat10 exhibits markedly lower thermodynamic stability and faster unfolding kinetics compared to ubiquitin. This is due to the absence …

The Cdk8 Kinase Module: A Novel Player In The Transcription Of Translation Initiation And Ribosomal Genes, Brittany Friedson, Stephen D Willis, Natalia Shcherbik, Alicia N Campbell, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Survival following stress is dependent upon reprogramming transcription and translation. Communication between these programs following stress is critical for adaptation but is not clearly understood. The Cdk8 kinase module (CKM) of the Mediator complex modulates the transcriptional response to various stresses. Its involvement in regulating translational machinery has yet to be elucidated, highlighting an existing gap in knowledge. Here, we report that the CKM positively regulates a subset of ribosomal protein (RP) and translation initiation factor (TIF)-encoding genes under physiological conditions in Saccharomyces cerevisiae. In mouse embryonic fibroblasts and HCT116 cells, the CKM regulates unique sets of RP and TIF …

Identification Of Benzothiophene-Derived Inhibitors Of Flaviviruses By Targeting Rna-Dependent Rna Polymerase, Leah Liu Wang, Shazeed-Ul Karim, Aidan Hand, Ryan Brunkhorst, Mackenna Petersen, Sarah Altam, Yi Liu, Luwen Zhang, Fengwei Bai, Shi-Hua Xiang

School of Biological Sciences: Faculty Publications

Flaviviruses such as Dengue, West Nile, and Zika viruses are mosquito-borne RNA viruses that can cause serious diseases in humans. To develop effective drugs for treating these viruses’ infections, we create a new approach for developing common or shared drugs that may work for several different viral species of flaviviruses. It is based on the conserved RNA-dependent RNA polymerase (RdRp), which is the key enzyme for viral replication. We built up a common structure of RdRps (POLcon) from their consensus sequence. A conserved Triple-D structural motif was identified at the active site of POLcon that has been used for virtual …

Clonal Variation In Effector Gene Expression As A Mechanism For Pathogenic Adaptation In Magnaporthe Oryzae, Rebekah J. Ellsworth

Theses and Dissertations--Plant Pathology

Magnaporthe oryzae is a filamentous fungal pathogen that causes destructive diseases in cereals, including rice blast, wheat blast, and gray leaf spot. It is responsible for 10–30% annual yield losses in rice (Nalley et al., 2016) and up to 100% loss in wheat under favorable conditions (Kohli et al., 2011). Disease management typically relies on the use of resistant cultivars, but M. oryzae rapidly overcomes host resistance by mutating or deleting avirulence (AVR) genes recognized by host immune receptors. This rapid adaptation, often occurring within one to two growing seasons, presents a major challenge to breeding for durable resistance.

The …

Utilizing Β-Gal To Visualize Selective Transport Of The Ssa4 Gene In S.Cerevisiae, Ian M. Staertow, Rebecca L. Adams Phd

Science University Research Symposium (SURS)

In eukaryotic cells such as Saccharomyces cerevisiae, protein synthesis begins with the transport of mRNA from the nucleus to the cytoplasm. In order for mRNA to leave the nucleus, it must first bind to specific transport proteins which can then facilitate transport via the nuclear pore complex (NPC), a selectively permeable membrane within the cell's nuclear envelope. Under environmental stress, such as heat shock, S. cerevisiae cells modulate transport rates. In this case, in heat stress or “heat shock” most mRNA transcripts will remain in the nucleus. The SSA4 transcript encodes for a chaperone protein which facilitates the subsequent export …

Borreliosis And Doxycycline Treatment Disrupt Gut Microbiota And Immune Responses In Nonhuman Primates, Ethan G. Napier, Isaac R. Cinco, Sheridan B. Wagner, Ethan V. Stuart, Qi Qiao, Joshua Taylor, Brian Stevenson, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Borrelia burgdorferi (Bb) is the spirochete that causes Lyme disease (LD). Transmission to humans occurs via bites of infected Ixodes spp. ticks. Doxycycline is often used to treat LD patients, which is sometimes delayed due to current diagnostic challenges. Recently, several lines of evidence show dysbiosis of the gut microbiome in LD patients, which may be a host factor contributing to pathogenesis and symp tomology but is still an understudied area in the field. To address this knowledge gap, we longitudinally compared the immune response and gut microbial composi tion of Japanese macaques after intradermal infection with Bb strain 297 …

Chronic Alcohol Consumption Induces Phenotypic And Functional Alterations Consistent With A Hyper-Inflammatory State In Peripheral Blood Mononuclear Cell-Derived Microglia In A Rhesus Macaque Model, Hami Hemati, Madison B. Blanton, Heather E. True, Jude Koura, Rupak Khadka, Kathleen A. Grant, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Alcohol-induced dysregulation of microglial activity is associated with neuroinflammation, cognitive decline, heightened risk for neurodegenerative diseases, alcohol dependence, and escalation of alcohol drinking. Given the challenge of longitudinally sampling primary microglia, we optimized an in vitro method to differentiate peripheral blood mononuclear cells (PBMC) from rhesus macaque (RM) into induced microglia-like cells (RM-iMGLs). The RM-iMGLs displayed transcriptional profiles distinct from monocyte progenitors and closely resembling primary microglia. Notably, morphological features showed that differentiated RM-iMGLs derived from subjects with chronic alcohol consumption (CAC), while bigger, exhibited a bipolar-like morphology. Additionally, dysregulation in key inflammatory and regulatory markers, along with increased baseline …

Role Of Chemotype In Aggressiveness, Toxicity, And Competitive-Ness Of Fusarium Graminearum On Wheat, Simran Goyal

Theses and Dissertations--Plant Pathology

Fusarium Head Blight (FHB) of wheat, caused by the fungus Fusarium graminearum, is a devastating disease that led to epidemics in the U.S. during the 1990s, resulting in economic losses exceeding $2.6 billion. Typical symptoms include bleached spikelets and shriveled grains, often contaminated with trichothecene mycotoxins that make them unsafe for food or feed. FHB severity and mycotoxin production are influenced by a complex interplay between host genotype, environmental factors, and pathogen genotype. Integrated management practices that include the use of more resistant cultivars, crop rotation, and fungicide applications help to reduce disease incidence and severity. Disease forecasting models …

Impact Of Obesity On The Gut Microbiome And Inflammatory Markers During Siv Infection And Antiretroviral Therapy, Casey M. Mcguire, Isaac R. Cinco, Diana Takahashi, Kristin A. Sauter, Melissa Kirigiti, Ilhem Messaoudi, Jonah B. Sacha, Charles T. Roberts, Paul Kievit

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Dysbiosis and impaired gut barrier integrity contribute to chronic immune activation associated with both obesity and HIV infection. Given the increased incidence of obesity in people living with HIV, we explored the impact of obesity on the gut microbiome and microbial translocation (MT) biomarkers during HIV infection and antiretroviral therapy (ART). Lean and obese rhesus macaques were infected with simian immunodeficiency virus (SIV) and subsequently treated with ART. Obese animals exhibited higher initial MT and inflammation biomarkers that remained constant throughout the study, while lean animals exhibited significant increases in these biomarkers that approached levels observed in obese animals. Lean …