Cell and Developmental Biology Commons^™

Sars‑Cov‑2 Entry Into And Evolution Within A Skilled Nursing Facility, Nicole R. Sexton, Parker Parker Cline, Emily N. Gallichotte, Emily Fitzmeyer, Michael C. Young, Ashley J. Janich, Kristy L. Pabilonia, Nicole Ehrhart, Gregory D. Ebel

Nebraska Center for Virology: Faculty Publications

SARS-CoV-2 belongs to the family Coronaviridae which includes multiple human pathogens that have an outsized impact on aging populations. As a novel human pathogen, SARS-CoV-2 is undergoing continuous adaptation to this new host species and there is evidence of this throughout the scientific and public literature. However, most investigations of SARS-CoV-2 evolution have focused on largescale collections of data across diverse populations and/or living environments. Here we investigate SARS-CoV-2 evolution in epidemiologically linked individuals within a single outbreak at a skilled nursing facility beginning with initial introduction of the pathogen. The data demonstrate that SARSCoV- 2 was introduced to the …

Structural Diversity And Stress Regulation Of The Plant Immunity-Associated Calmodulin-Binding Protein 60 (Cbp60) Family Of Transcription Factors In Solanum Lycopersicum (Tomato), Vanessa Shivnauth, Sonya Pretheepkumar, Eric J. R. Marchetta, Christina A. M. Rossi, Keaun Amani, Christian Castroverde

Biology Faculty Publications

Cellular signaling generates calcium (Ca2+) ions, which are ubiquitous secondary messengers decoded by calcium-dependent protein kinases, calcineurins, calreticulin, calmodulins (CAMs), and CAM-binding proteins. Previous studies in the model plant Arabidopsis thaliana have shown the critical roles of the CAM-BINDING PROTEIN 60 (CBP60) protein family in plant growth, stress responses, and immunity. Certain CBP60 factors can regulate plant immune responses, like pattern-triggered immunity, effector-triggered immunity, and synthesis of major plant immune-activating metabolites salicylic acid (SA) and N-hydroxypipecolic acid (NHP). Although homologous CBP60 sequences have been identified in the plant kingdom, their function and regulation in most species remain unclear. In …

Yes-Associated Protein-1 Overexpression In Ocular Surface Squamous Neoplasia; A Potential Diagnostic Marker And Therapeutic Target, Peter Julius, Stepfanie N. Siyumbwa, Fred Maate, Phyllis Moonga, Guobin Kang, Trevor Kaile, John T. T., Charles Wood

Nebraska Center for Virology: Faculty Publications

Yes-associated protein-1 (YAP-1) is a Hippo system transcription factor, which serves as an oncogene in squamous cell carcinoma, and several solid tumors when the Hippo pathway is dysregulated. Yet, the activity of YAP-1 in ocular surface squamous neoplasia (OSSN) has not been determined. Here, we investigate the relationship between YAP-1 overexpression and OSSN. Using a cross-sectional study design, we recruited 227 OSSN patients from the University Teaching Hospitals in Lusaka, Zambia. Immunohistochemistry was used to assess YAP-1 protein overexpression in tumor tissue relative to surrounding benign squamous epithelium. OSSN patient samples (preinvasive, n = 62, 27% and invasive, n = …

Regulation Of The Wnt/Wingless Receptor Lrp6/Arrow By The Deubiquitylating Complex Usp46, Zachary T. Spencer

Dartmouth College Ph.D Dissertations

The evolutionarily conserved Wnt/Wingless signal transduction pathway is critical for the proper development of all animals and implicated in numerous diseases in adulthood. Upon binding of the Wnt/Wingless ligand, a cascade of events culminates in inactivation of the destruction complex, a negative regulator of the pathway, and the subsequent formation of singalosomes which mediate pathway activation. A critical component of signalosome formation is the Wnt/Wingless receptor LRP6/Arrow. Upon canonical pathway activation, LRP6/Arrow undergoes activation via phosphorylation by several kinases and complexes with another Wnt/Wingless receptor Frizzled, along with several cytoplasmic components. While many studies have investigated the regulatory mechanisms of …

The Pros Of Changing Trna Identity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance.

Atomistic Assessment Of Drug-Phospholipid Interactions Consequent To Cancer Treatment: A Study Of Anthracycline Cardiotoxicity, Yara Elsayed Ahmed

Theses and Dissertations

Despite being one of the most effective chemotherapeutic agents developed to date, Anthracyclines are notorious for their cardiotoxicity. Their clinical use is frequently limited both in dosage and in prescription due to the severe cardiac damage they cause. The mechanism of anthracycline-induced cardiotoxicity is not yet fully understood. However, it is hypothesized that interactions with the myocardial membrane play an important role in imparting cardiotoxicity. In this study, we use molecular dynamics simulations and density functional theory calculations to study the anthracycline drug molecules and the interactions that they have with the myocardial membrane. We construct a myocardial membrane model …

Viral Dna Accumulation Regulates Replication Efficiency Of Chlorovirus Osy-Ne5 In Two Closely Related Chlorella Variabilis Strains, Ahmed Esmael, Irina V. Agarkova, David D. Dunigan, You Zhou, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Many chloroviruses replicate in Chlorella variabilis algal strains that are ex-endosymbionts isolated from the protozoan Paramecium bursaria, including the NC64A and Syngen 2-3 strains. We noticed that indigenous water samples produced a higher number of plaque-forming viruses on C. variabilis Syngen 2-3 lawns than on C. variabilis NC64A lawns. These observed differences led to the discovery of viruses that replicate exclusively in Syngen 2-3 cells, named Only Syngen (OSy) viruses. Here, we demonstrate that OSy viruses initiate infection in the restricted host NC64A by synthesizing some early virus gene products and that approximately 20% of the cells produce a …

Ethical Issues And Standards Of Responsible Research Conduct And Monitoring In An Adventist Institution Of Higher Learning - The Babcock Experience, Kayode O. Ogunwenmo, Godswill N. Anyasor, Grace O. Tayo

Adventist Human-Subject Researchers Association

Ethical issues and standards of responsible research conduct involving human participants are important considerations in any institution of higher learning and in particular Adventist institutions. Research conduct and ethics are reviewed and approved before they begin by the Babcock University Health Research Ethics Committee (BUHREC)

Influenza C And D Viruses Demonstrated A Differential Respiratory Tissue Tropism In A Comparative Pathogenesis Study In Guinea Pigs, Chithra C. Sreenivasan, Runxia Liu, Rongyuan Gao, Yicheng Guo, Ben M. Hause, Milton Thomas, Ahsan Naveed, Travis Clement, Dana Rausch, Jane Christopher-Hennings, Eric Nelson, Julian Druce, Miaoyun Zhao, Radhey S. Kaushik, Qingsheng Li, Zizhang Sheng, Dan Dan, Feng Li

Nebraska Center for Virology: Faculty Publications

Influenza C virus (ICV) is increasingly associated with community-acquired pneumonia (CAP) in children and its disease severity is worse than the influenza B virus, but similar to influenza A virus associated CAP. Despite the ubiquitous infection landscape of ICV in humans, little is known about its replication and pathobiology in animals. The goal of this study was to understand the replication kinetics, tissue tropism, and pathogenesis of human ICV (huICV) in comparison to the swine influenza D virus (swIDV) in guinea pigs. Intranasal inoculation of both viruses did not cause clinical signs, however, the infected animals shed virus in nasal …

Zinc Treatment Reverses And Anti-Zn-Regulated Mirs Suppress Esophageal Carcinomas In Vivo, Louise Fong, Kay Huebner, Ruiyan Jing, Karl Smalley, Christopher R Brydges, Oliver Fiehn, John Farber, Carlo M Croce

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Esophageal squamous cell carcinoma (ESCC) is a deadly disease with few prevention or treatment options. ESCC development in humans and rodents is associated with Zn deficiency (ZD), inflammation, and overexpression of oncogenic microRNAs: miR-31 and miR-21. In a ZD-promoted ESCC rat model with upregulation of these miRs, systemic antimiR-31 suppresses the miR-31-EGLN3/STK40-NF-κB-controlled inflammatory pathway and ESCC. In this model, systemic delivery of Zn-regulated antimiR-31, followed by antimiR-21, restored expression of tumor-suppressor proteins targeted by these specific miRs: STK40/EGLN3 (miR-31), PDCD4 (miR-21), suppressing inflammation, promoting apoptosis, and inhibiting ESCC development. Moreover, ESCC-bearing Zn-deficient (ZD) rats receiving Zn medication showed a 47% …

Adenoviral-Vectored Epigraph Vaccine Elicits Robust, Durable, And Protective Immunity Against H3 Influenza A Virus In Swine, Erika M. Petro-Turnquist, Matthew J. Pekarek, Nicholas Jeanjaquet, Cedric Wooledge, David J. Steffen, Hiep Vu, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Current methods of vaccination against swine Influenza A Virus (IAV-S) in pigs are infrequently updated, induce strain-specific responses, and have a limited duration of protection. Here, we characterize the onset and duration of adaptive immune responses after vaccination with an adenoviral-vectored Epigraph vaccine. In this longitudinal study we observed robust and durable antibody responses that remained above protective titers six months after vaccination. We further identified stable levels of antigen-specific T cell responses that remained detectable in the absence of antigen stimulation. Antibody isotyping revealed robust class switching from IgM to IgG induced by Epigraph vaccination, while the commercial comparator …

Quantitative And Qualitative Analysis Of Mutation In Pam-1 Of Model Organism Caenorhabditis Elegans., Jessica Stein, Jessica Stein

Honors College Theses

The pam-1 gene in the model roundworm Caenorhabditis elegans governs meiotic exit and establishment of cellular polarity in the single-celled C. elegans embryo. Mutation of the pam-1 gene results in reduced fertility and fecundity in adult C. elegans and disrupts the anatomy of the germinal gonad. The aim of this study is to qualitatively and quantitatively define the changes in the germline cells associated with mutations to the pam-1 gene. Specifically, we examined the stages of germ cell development within the gonads of adult worms, both wild-type and pam-1 compromised, and identified the changes in the length of the mitotic, …

Orthologs Of The C. Elegans Heterochronic Genes Have Divergent Functions In C. Briggsae, Maria Ivanova, Eric G. Moss

Rowan-Virtua Research Day

The heterochronic genes of C. elegans comprise the best-studied pathway controlling the timing of tissue and organ formation in an animal. To begin to understand the evolution of this pathway, the significance of each factor, and the relationships among the components, we characterized 11 C. briggsae orthologs of C. elegans heterochronic genes. Using CRISPR/Cas9, we made a variety of alleles and found that several mutant phenotypes differ in significant ways from those of C. elegans. Although most orthologs displayed defects in developmental timing, those phenotypes could differ in which stages they controlled, the penetrance and expressivity of the phenotypes, or …

Review Of Biomedical Applications Of Cardiovascular Tissue Engineering, Natalie M. Howard

Honors College Theses

Tissue engineering can be defined as processes that aim to generate three-dimensional functional tissues in vitrothat have been favorably altered according to the structural, biochemical, electrophysiological, and biomechanical properties of the desired tissue before implantation into the human body. In relation to cardiac tissues, these properties would include the ability to conduct action potentials, withstand systolic pressure, permit sufficient O₂ and CO₂penetration, sufficient vascularization to supply nutrients for cellular activity, surface topology that enables cellular communication, and more. As heart diseases and instances of myocardial infarction continue to rise worldwide, there is an increasing need for …

Transcriptional Regulation Of Stem Cell Function In The Drosophila Central Nervous System, Amalia S. Parra

Biology ETDs

Development of multicellular organisms depends on coordination of various molecular mechanisms to ensure proper tissue size and structure. This is accomplished through intrinsic and extrinsic cues that regulate cell growth and proliferation both spatially and temporally. These well-coordinated signals are present from early developmental stages and remain active throughout development to ensure tissue structure is appropriate for function. This is particularly important in early cell types that form specialized lineages such as stem cells or those found throughout the body such as epithelia. While much progress has been made in understanding growth regulatory mechanisms, several fundamental aspects remain unknown. This …

A Dna-Peptide Crosslink (Dpc) Increases Mutagenicity In Sos-Induced Escherichia Coli, Alessandra Bassani

Honors Scholar Theses

Bacteria, such as Escherichia coli, have an inducible system in response to DNA damage termed the SOS response. This system is activated when the replicative DNA polymerase (Pol) III encounters a lesion, uncouples from DNA helicase, and single-stranded DNA (ssDNA) accumulates at the replication fork. In this study, we investigated DNA-peptide crosslink (DpC), a common lesion that results from cross-linking of proteins or peptides, UV irradiation, and alkylating agents. To increase survival following formation of a lesion, the SOS response can utilize homologous recombination, translesion synthesis (TLS), or excision repair. With TLS, the levels of DNA Pol II, IV, …

Validating A New In Vivo Model To Study Als, Izabela J. Cimachowska

Student Theses and Dissertations

Buildup of oxidative stress and mitochondrial dysfunction are well known characteristics of both sporadic and hereditary amyotrophic lateral sclerosis (ALS). While both forms of the disease seem to arise from common cellular dysfunction, the genetic disease is studied to a much greater extent. Engineering novel animal models of the sporadic form of the disease is crucial for development of druggable targets to treat ALS and understand the underlying mechanisms. Interestingly, accumulation of oxidative stress by exacerbated emission of reactive oxygen species (ROS) from presynaptic mitochondria is a hallmark of both hereditary and sporadic ALS. Previous work by our laboratory showed …

Methyltransferase, Glucose Adaptation, And Import Complex In Trypanosoma Brucei, Emily Knight

All Dissertations

Trypanosoma brucei is a kinetoplastid parasite responsible for human African trypanosomiasis (HAT) and nagana, a livestock wasting disease, which both endemic to sub-Saharan Africa. Unique to kinetoplastids are the specialized peroxisomes, named glycosomes, which compartmentalize the first several steps of glycolysis and gluconeogenesis, nucleotide sugar biosynthesis, and many other metabolic processes. Kinetoplastids are unique in that they have a single mitochondrion. In this work, I present the first study into SET domain proteins in any kinetoplastid parasites. We have characterized a predicted SET domain protein, TbSETD3, that localizes to the mitochondrion and a depletion of the protein results in growth …

Unique Transcriptional Profiles Underlie Osteosarcomagenesis Driven By Different P53 Mutants, Dhruv Chachad

Dissertations and Theses (Open Access)

Missense mutations in the DNA binding domain of the Trp53 gene are characterized as structural (p53R172H) or contact (p53R245W) mutations based on their effect on the conformation of the protein. These mutations show gain-of-function activities such as increased metastatic incidence as compared to p53 loss, often mediated by their interaction with a repertoire of transcription factors. These interactions are largely context specific. In order to understand the mechanisms by which these mutations drive osteosarcoma progression, we created a mouse model, wherein either the p53 structural mutant p53R172H, or the contact mutant, p53R245W, are expressed specifically in …

P53 Dimers Elicit Unique Tumor Suppressive Activities Through An Altered Metabolic Program, Jovanka Gencel-Augusto

Dissertations and Theses (Open Access)

p53 is the most frequently mutated tumor suppressor in human cancer. As a tetrameric transcription factor, mutation of the p53 Tetramerization Domain (TD) is a mechanism by which cancers abrogate wild-type (WT) p53 function. p53 TD mutations result in a protein that preferentially forms monomers or dimers. These are also normal p53 states under basal cellular conditions. Although it is accepted that tetrameric p53 is required for full tumor suppressive activities, the physiological relevance of monomeric and dimeric states of p53 is not well understood. We have established in vivo models for monomeric and dimeric p53 which model Li-Fraumeni Syndrome …

Targeting Metabolic Alterations Associated With Smooth Muscle Α-Actin Pathogenic Variant Attenuates Moyamoya-Like Cerebrovascular Disease, Anita Kaw

Dissertations and Theses (Open Access)

Heterozygous pathogenic variants in ACTA2, encoding smooth muscle α-actin (α-SMA), predispose to thoracic aortic aneurysms and dissections. De novo missense variants disrupting ACTA2 arginine 179 (p.Arg179) cause a multisystemic disease termed smooth muscle dysfunction syndrome (SMDS), which is characterized by early onset thoracic aortic disease and moyamoya disease-like (MMD) cerebrovascular disease. The MMD-like cerebrovascular disease in SMDS patients is marked by bilateral steno-occlusive lesions in the distal internal carotid arteries (ICAs) and their branches. To study the molecular mechanisms that underlie the ACTA2 p.Arg179 variants, a smooth muscle-specific Cre-lox knock-in mouse model of the heterozygous Acta2 R179C variant, termed …

Regulation Of De Novo And Maintenance Dna Methylation By Dnmt3a And Dnmt3b, Yang Zeng

Dissertations and Theses (Open Access)

DNA methylation (5-methylcytosine, 5mC) is essential for the regulation of gene expression and integrity of the mammalian genome. It occurs predominantly in the context of CpG dinucleotides to form a symmetrical pattern on both DNA strands, which allows DNA methylation patterns to be semi-conservatively maintained during DNA replication. There are two classes of DNA methyltransferases (DNMTs): DNMT3A and DNMT3B function primarily as de novo methyltransferases that establish DNA methylation patterns, whereas DNMT1 is the major enzyme responsible for maintaining DNA methylation patterns by converting hemi-methylated CpGs to fully methylated CpGs during DNA replication. Two accessory factors also play critical regulatory …

Genetic Regulation Of Müllerian Duct Regression, Malcolm Moses

Dissertations and Theses (Open Access)

Mammals, including humans, develop progenitor tissues for both male and female reproductive tract organs before they fully differentiate into a male or female tract. The progenitor tissue for the male reproductive tract is known as the Wolffian duct (WD), and the progenitor tissue for the female reproductive tract is the Müllerian duct (MD). The WD further differentiates into the vas deferens, epididymis, and seminal vesicle, while the MD differentiates into the oviduct, uterus and upper vagina. An essential step in sex differentiation for males is the regression of the MD. This regression initiates with anti-Müllerian hormone (Amh) transcription …

Gonads Without Glp-1: Silencing Glp-1 In The Male Somatic Gonad In Caenorhabditis Elegans, Matthew Titus

Undergraduate Theses

In C. elegans, the gene glp-1 encodes for a Notch receptor called GLP-1, one of two found in C. elegans’ genome. The gene has been previously implicated in the development of the hermaphroditic germline as well as playing a role in the mitosis/meiosis decision. Genetic screening has further identified it as potentially playing a role in the development of the male somatic gonad, making it an ideal candidate for a reverse genetic. We did this by silencing glp-1 and observing if any alterations to the gonad’s phenotype occur.

Normally this could be done by performing a gene knockout. …

Understanding The Expression And Role Of Pros-1 In The Male Gonad Of C. Elegans, Jack Bozik

Undergraduate Theses

The gene pros-1 is a transcription factor that is highly expressed within neuronal sheath cells, glial cells, and excretory canal cells. pros-1 plays a role in cell determination of those cell types in the nematode C. elegans, which promotes organismal development. But the degree to which pros-1 presence is important is still not fully understood, because there are many genes involved in development that when mutated or damaged can result in unexpected phenotypes or even total loss of function to a certain developmental mechanism. What makes pros-1 valuable to research is that it is a functional homologue to a …

Role Of Cdx4 And Sp5l In Zebrafish Development, Wesley Tsai

Honors Theses

The Caudal Type Homeobox transcription factors cdx are a family of genes found in vertebrates that regulates body regionalization and anterior-posterior patterning. They are also responsible for regulating axial elongation, but the mechanisms behind this behavior are not known. Previous studies in mouse embryonic stem cells have shown that the cdx genes are necessary for upregulating the gene sp5 which may be linked to axial elongation. Sp5 is a zinc-finger transcription factor belonging to the specificity protein (sp) family. Our group has used in-situ hybridization experiments on zebrafish embryos to show that sp5-like (sp5l) is transcribed within tailbud tissues that …

Analysis Of Wild Rodent Gut Microbiota As A Function Of Exposure To Ticks And Tick-Borne Pathogens, Joshua Pandian

Honors Theses

Due to advances in high-throughput parallel sequencing, researchers have conducted novel studies exploring relationships between microbiome compositions and different aspects of organism health. Some of these studies have shown that the gut microbiome of rodent models has effects on organism health and behavior and that infection with pathogens and the composition of the skin microbiome are linked to changes in gut microbiome composition. While previous studies have shown how vector microbiota impact vector behavior and pathogen transmission, the effect vectors have on reservoir species microbiomes has been a less prominent focus. We were interested in the relationships between tick parasitism, …

Pyrus Calleryana Extracts Reduce Germination Of Native Grassland Species, Suggesting The Potential For Allelopathic Effects During Ecological Invasion, Michaela J. Woods, Jonathan T. Bauer, Dena Schaeffer, Ryan W. Mcewan

Biology Faculty Publications

Invasive plant species’ success may be a result of allelopathy, or the release of secondary metabolites that are harmful for surrounding plant species. Allelopathy can be mediated through the abiotic environment by chemical sorption or transformation, so the substrate on which interactions occur can lead to differential outcomes in allelopathic potential. One aggressive invader, Pyrus calleryana, has become dominant in many ecosystems throughout Eastern US, and has reduced the abundance of native species where it invades. Thus, our goal was to identify if P. calleryana had allelopathic potential by testing the impact of leaf and flower leachate on gemination …

Application Of A Novel Lytic Jerseyvirus Phage Lpsent1 For The Biological Control Of The Multidrug-Resistant Salmonella Enteritidis In Foods, Rashad R. Al-Hindi, Mona G. Alharbi, Ibrahim Alotibi, Sheren A. Azhari, Khloud M. Algothmi, Ahmed Esmael

Nebraska Center for Virology: Faculty Publications

Non-typhoidal Salmonella is the tremendously predominant source of acquired foodborne infection in humans, causing salmonellosis which is a global threat to the healthcare system. This threat is even worse when it is combined with the incidence of multidrug-resistant Salmonella strains. Bacteriophage therapy has been proposed as a promising potential candidate to control a diversity of foodborne infective bacteria. The objective of this study designed to isolate and characterize lytic phages infecting zoonotic multi-drug resistant and strong biofilm producer Salmonella enterica serovar Enteritidis EG.SmE1 and then apply the isolated phage/s as a biocontrol agent against infections in ready-to-eat food articles including …

The Sars-Cov-2 Utr’S Intrudes Host Rbp’S And Modulates Cellular Splicing, Anjali Singh, Kush Kumar Pandey, Shubham Kumar Agrawal, Rupesh K. Srivastava, Sankar Bhattacharyya, Bhupendra Verma

Nebraska Center for Virology: Faculty Publications

SARS-CoV-2 is a novel coronavirus that causes a potentially fatal respiratory disease known as coronavirus disease (COVID-19) and is responsible for the ongoing pandemic with increasing mortality. Understanding the host-virus interaction involved in SARS-CoV-2 pathophysiology will enhance our understanding of the mechanistic basis of COVID-19 infection. The characterization of post-transcriptional gene regulatory networks, particularly pre-mRNA splicing, and the identification and characterization of host proteins interacting with the 5' and 3'UTRs of SARS-CoV-2 will improve our understanding of posttranscriptional gene regulation during SARS-CoV-2 pathogenesis. Here, we demonstrate that either SARS-CoV-2 infection or exogenous overexpression of the 5' and 3’UTRs of the …