Cell and Developmental Biology Commons^™

Bacterial Association Networks From Healthy And Cancer-Associated Gut Microbiomes, Mark Loftus

Electronic Theses and Dissertations, 2020-2023

The human gastrointestinal tract is colonized by a diverse community of symbiotic microorganisms, mainly bacteria, that are known to play essential roles in maintaining the health of their human host. Disruption of this bacterial community has been associated with numerous diseases, including Colorectal Cancer (CRC). CRC is one of the leading causes of cancer-related deaths worldwide. As such, focus has been placed on the modulation of the bacterial community within the cancer-associated gut microbiome as the next step in possible CRC treatment and prevention strategies. To use the bacterial community for these purposes, a better understanding of the associations that …

Impact Of The Histidine‐Containing Phosphocarrier Protein Hpr On Carbon Metabolism And Virulence In Staphylococcus Aureus, Linda Pätzold, Anne-Christine Brausch, Evelyn-Laura Bielefeld, Lisa Zimmer, Greg A. Somerville, Markus Bischoff, Rosmarie Gaupp

School of Veterinary and Biomedical Sciences: Faculty Publications

Carbon catabolite repression (CCR) is a common mechanism pathogenic bacteria use to link central metabolism with virulence factor synthesis. In gram‐positive bacteria, catabolite control protein A (CcpA) and the histidine‐containing phosphocarrier protein HPr (encoded by ptsH) are the predominant mediators of CCR. In addition to modulating CcpA activity, HPr is essential for glucose import via the phosphotransferase system. While the regulatory functions of CcpA in Staphylococcus aureus are largely known, little is known about the function of HPr in CCR and infectivity. To address this knowledge gap, ptsH mutants were created in S. aureus that either lack the open reading …

An Evaluation Of The Anti-Carcinogenic Response Of Major Isothiocyanates In Non-Metastatic And Metastatic Melanoma Cells, Melina Mitsiogianni, Sotiris Kyriakou, Ioannis Anestopoulos, Dimitrios T. Trafalis, Maria V. Deligiorgi, Rodrigo Franco, Aglaia Pappa, Mihalis I. Panayiotidi

School of Veterinary and Biomedical Sciences: Faculty Publications

Malignant melanoma is one of the most deadly types of solid cancers, a property mainly attributed to its highly aggressive metastatic form. On the other hand, different classes of isothiocy- anates, a class of phytochemicals, present in cruciferous vegetables have been characterized by considerable anti-cancer activity in both in vitro and in vivo experimental models. In the current study, we investigated the anti-cancer response of five isothiocyanates in an in vitro model of melanoma consisting of non-metastatic (A375, B16F-10) and metastatic (VMM1, Hs294T) malignant melanoma as well as non-melanoma epidermoid carcinoma (A431) and non-tumorigenic melanocyte-neighboring keratinocyte (HaCaT) cells. Our aim …

Il-10 As A Th2 Cytokine: Differences Between Mice And Humans, Mahima T. Rasquinha, Meghna Sur, Ninaad Lasrado, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

The discovery of interleukin (IL)-10 more than 30 years ago marked the beginning of our understanding of how cytokines regulate immune responses, based on cross-regulation between T helper (Th)1 and Th2 cytokines. Although multiple cell types were shown to produce IL-10, its identity as a Th2 cytokine remained strong since it was rigidly associated with Th2 clones in mice, whereas both Th1 and Th2 clones could secrete IL-10 in humans. However, as new Th1/Th2 cell functionalities emerged, anti-inflammatory action of IL-10 gained more attention than its inhibitory effect on Th1 cells, which may occur as an indirect consequence of suppression …

Tetraspanins As Potential Therapeutic Candidates For Targeting Flaviviruses, Waqas Ahmed, Girish Neelakanta, Hameeda Sultana

Biological Sciences Faculty Publications

Tetraspanin family of proteins participates in numerous fundamental signaling pathways involved in viral transmission, virus-specific immunity, and virus-mediated vesicular trafficking. Studies in the identification of novel therapeutic candidates and strategies to target West Nile virus, dengue and Zika viruses are highly warranted due to the failure in development of vaccines. Recent evidences have shown that the widely distributed tetraspanin proteins may provide a platform for the development of novel therapeutic approaches. In this review, we discuss the diversified and important functions of tetraspanins in exosome/extracellular vesicle biology, virus-host interactions, virus-mediated vesicular trafficking, modulation of immune mechanism(s), and their possible role(s) …

Self And Microbiota-Derived Epitopes Induce Cd4⁺ T Cell Anergy And Conversion Into Cd4⁺Foxp3⁺ Regulatory Cells, Michal P. Kuczma, Edyta A. Szurek, Anna Cebula, Vu L. Ngo, Maciej Pietrzak, Piotr Kraj, Timothy L. Denning, Leszek Ignatowicz

Biological Sciences Faculty Publications

The physiological role of T cell anergy induction as a key mechanism supporting self-tolerance remains undefined, and natural antigens that induce anergy are largely unknown. In this report, we used TCR sequencing to show that the recruitment of CD4⁺CD44⁺Foxp3⁻CD73⁺FR4⁺ anergic (Tan) cells expands the CD4⁺Foxp3⁺ (Tregs) repertoire. Next, we report that blockade in peripherally-induced Tregs (pTregs) formation due to mutation in CNS1 region of Foxp3 or chronic exposure to a selecting self-peptide result in an accumulation of Tan cells. Finally, we show that microbial antigens from Akkermansia muciniphila …

Periocular Mesenchyme Heterogeneity During Morphogenesis Of The Vertebrate Ocular Anterior Segment, Kristyn L. Van Der Meulen

Theses and Dissertations--Biology

The vertebrate eye is a complex organ, responsible for the primary sense with which we interact with our environment: vision. Development of the eye is a tightly regulated process, controlled by a vast network of genes. This process begins with eye morphogenesis, when the eye structure is formed through a series of morphogenetic movements and culminates in the creation of the optic cup, lens, and presumptive optic stalk. Next, retinal differentiation creates the critical cell layers of the retina needed to process light waves that enter the eye, including rod and cone photoreceptors, interneurons, and support cells. Failure in either …

Protocadherin-17 Expression And Function In Vertebrate Brain: A Literature Review, Mathea Mcguire

Williams Honors College, Honors Research Projects

For this project, I will be doing a systematic review on protocadherin-17 function in vertebrate brain development and function in the last 10 years. Protocadherins are members of cadherin superfamily. Cadherins are calcium-dependent cell adhesion molecules that are implicated to play crucial roles in the information and maintenance of tissues and organs in vertebrate animals. This review will summarize major findings regarding protocadherin-17 expression and function in major model organisms such as zebrafish and mice, as well as results from human studies. It is hoped that this work will be a valuable source for background knowledge of protocadherin-17 function in …

Leveraging Chemical And Computational Biology To Probe The Cellulose Synthase Complex, B. Kirtley Amos

Theses and Dissertations--Plant and Soil Sciences

Cellular expansion in plants is a complex process driven by the constraint of internal cellular turgor pressure by an expansible cell wall. The main structural element of the cell wall is cellulose. Cellulose is vital to plant fitness and the protein complex that creates it is an excellent target for small molecule inhibition to create herbicides. In the following thesis many small molecules (SMs) from a diverse library were screened in search of new cellulose biosynthesis inhibitors (CBI). Loss of cellular expansion was the primary phenotype used to search for putative CBIs. As such, this was approached in a forward …

The Effect Of Cxcl12 Ligand On Internalization And Dimerization Of Cxcr4 Receptors In Live Cells, Loga Iyer

Williams Honors College, Honors Research Projects

The primary objective of this project was to determine the effect of CXCL12 ligand binding on the CXCR4 receptor, specifically, how it would impact receptor internalization and dimerization. The CXCL12 ligand derives from the stromal cell-derived alpha family [8]. The CXCR4 receptors, known as C-X-C chemokine receptor type 4 play an essential role in controlling cell proliferation. When misregulated, these receptors can drive tumorigenesis and are thus important targets of cancer therapy. These G protein-coupled receptors stimulate a cascade of signaling pathways in specific tissues [1]. These pathways include the positive transcriptional control of CXCR4 via the Nuclear Respiratory Factor-1 …

Traction Force Is Modulated By The Calpain Small Subunit And Secreted Galectin-3, Imjoo Jang

Wayne State University Dissertations

Cell migration is a fundamental physical process for wound repair, innate immune response, embryonic development, inflammatory responses as well as cancer metastasis. Biochemical and mechanical cues present inside and outside the cell can modulate the mechanical aspects of cell migration. During cell migration, traction forces are generated by the contraction of the actomyosin cytoskeleton and transmitted to the extracellular matrix through integrin-mediated focal adhesions, facilitating the forward movement of the cell. Although regulating traction force is central to achieving successful cell migration, the detailed mechanism of the force production is still largely unclear. The calpain family of proteases has been …

Entry And Replication Of Negative-Strand Rna Viruses, Kerri Boggs

Theses and Dissertations--Molecular and Cellular Biochemistry

Hendra virus (HeV) and human metapneumovirus (HMPV) are negative-sense, singled-stranded RNA viruses. The paramyxovirus HeV is classified as a biosafety level 4 pathogen due to its high fatality rate and the lack of a human vaccine or antiviral treatment. HMPV is a widespread pneumovirus that causes respiratory tract infections which are particularly dangerous for young children, immunocompromised individuals, and the elderly. Like HeV, no vaccines or therapies are available to combat HMPV infections. These viruses fuse their lipid envelopes with a cell to initiate infection. Blocking cell entry is a promising approach for antiviral development, and many vaccines are designed …

Therapeutic Targeting Of Leukemia Stem Cells To Prevent T-Cell Acute Lymphoblastic Leukemia Relapse, Meghan G. Haney

Theses and Dissertations--Molecular and Cellular Biochemistry

The survival rate of T-cell Acute Lymphoblastic Leukemia (T-ALL) relapse is a dismal 10% of affected adults and 30% of children, largely due to the relapsed disease being more aggressive and treatment resistant than the initial disease. Relapse is thought to occur because conventional chemotherapies are unable to reliably eliminate a unique cell type known as leukemia stem (or propagating) cells (LSCs). LSCs are the only cells within the leukemia with the ability to self-renew and remake or replenish the ALL from a single cell. Currently, the pathways governing self-renewal in LSCs are largely unknown, precluding our ability to successfully …

Reversible Glucan Phosphorylation In The Red Alga, Cyanidioschyzon Merolae, Corey Owen Brizzee

Theses and Dissertations--Molecular and Cellular Biochemistry

Starch and glycogen are an essential component for the majority of species and have been developed to maintain homeostasis in response to environmental changes. Water-soluble glycogen is an excellent source of quick, short-term energy in response to energy demands. In contrast, plants and algae have developed the macromolecule starch that is elegantly suitable for their dependence on external circumstances. Semi-crystalline starch is water-insoluble and inaccessible to most amylolytic enzymes, thus plants and algae have developed a coordinated system so that these enzymes can gain access to the denser starch energy cache. Starch-like semi-crystalline polysaccharides are also found in red algae, …

The Role Of Autophagy And Senescence In The Responses Of Non-Small Cell Lung Cancer Cells To Chemotherapy And Radiation, Nipa H. Patel

Theses and Dissertations

Cancer-associated deaths account for the second-highest mortality rates in the United States. Primary modalities of treatment often include surgery, radiation, and chemotherapy, and may also incorporate targeted therapy and immunotherapy. However, resistance to these treatments remains high, resulting in disease reoccurrence and poor survival rates. While apoptosis or cell death of tumor cells is the ideal outcome for anti-cancer therapy, this is often not the case, and in fact cancer cells may upregulate several pathways, such as autophagy and senescence, as a means to undergo alternative cell fate and evade apoptotic cell death. An essential tumor suppressor gene, TP53, …

Regulation Of Osseous Healing By Macrophage-Derived Wnt Ligands, Jefferson Overlin Abaricia

Theses and Dissertations

Osseous healing is regulated by various classes of cells and signaling mechanisms. Of these, Wnt signaling has long been known to be critically important in directing the differentiation of mesenchymal stem cells (MSCs) into osteoblasts during bone healing. However, the source of these Wnt ligands is not known. Recently, a body of literature has arisen finding both beneficial and detrimental effects of macrophage-derived Wnt ligands on the regeneration of other tissues (liver, kidney, heart, and intestine), often by regulating inflammatory activation and stem cell behavior. As macrophages have been well-characterized as orchestrators of healing, their use of Wnt signaling to …

Molecular Mechanisms Regulating Optic Fissure Fusion During Zebrafish Eye Development, Megan Weaver

Theses and Dissertations--Biology

Vertebrate retinal development requires timely and precise fusion of the optic fissure. Failure of this event leads to congenital vision impairment in the form of coloboma. Recent studies have suggested hyaloid vasculature to be involved in OF fusion. In order to examine this link, we analyzed optic fissure fusion and hyaloid vasculogenesis in the zebrafish pax2a noi mutant line. We first determined that pax2a^-/- embryos fail to accumulate F-actin in the optic fissure prior to basement membrane (BM) degradation. Furthermore, using 3D and live imaging we observed reduced OF hyaloid vascularization in pax2a^-/- embryos. When examining the connection …

Leveraging Transcriptomic Approaches To Identify Differences In Genetic Programming Driving Two Distinct Wound Healing Mechanisms, Regeneration And Fibrosis, In Acomys And Mus, Shishir K. Biswas

Theses and Dissertations--Biology

Why can some animals and others cannot? This fundamental question has fueled scientists studying regeneration for hundreds of years since early observations in crayfish, salamanders and many other organisms. While most contemporary work in regeneration is done in a handful of species including salamanders, zebrafish and flatforms, these organisms lack a closely-related, non-regenerating sister species from which unique genetic differences can be identified. Additionally, while much has been learned from these organisms, they do not share fundamental biological traits with mammals (endothermy, metabolism and immune system) which limits the ability to translate this research for clinical medicine. To this end, …

Cellular Bioenergetics Regulates Cell Proliferation During Mammalian Regeneration, Sandeep Saxena

Theses and Dissertations--Biology

Mammalian system consists of stress-sensing molecules that regulates their cellular response against damage, injury and oncogenic stress. During vertebrate regeneration, cells responding to injury re-enter the cell cycle and proliferate to form new tissue. Cell cycle re-entry or arrest is at least partly regulated by cellular senescence which negatively impacts the proliferative pool of cells during regeneration. What remains unclear is whether cells in regenerating systems possess an increased propensity to proliferate and are refractory to signals that induce senescence. My thesis work has focused on how fibroblasts from the ear pinna differentially regulate healing in highly regenerative mammals (e.g., …

High Prevalence Of Pre-Existing Serological Cross-Reactivity Against Severe Acute Respiratory Syndrome Coronavirus-2 (Sars- Cov-2) In Sub-Saharan Africa, For Yue Tso, Salum Lidenge, Phoebe B. Peña, Ashley A. Clegg, John R. Ngowi, Julius Mwaiselage, Owen Ngalamika, Peter Julius, John T. West, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective: Significant morbidity and mortality have occurred in the USA, Europe, and Asia due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), whereas the numbers of infections and deaths in sub-Saharan Africa (SSA) have remained comparatively low. It has been hypothesized that exposure of the population in SSA to other coronaviruses prior to the COVID-19 pandemic resulted in some degree of cross-protection against SARS-CoV-2 infection and pathogenesis. We evaluated this hypothesis by comparing SARS-CoV-2 cross-reactive antibodies in pre-pandemic plasma samples collected from SSA and the USA.

Method: Pre-COVID-19 pandemic plasma samples from SSA and the USA were collected and tested by …

The 20th Anniversary Meeting Of The Rocky Mountain Virology Association, Joel Rovnak, Laura A. St Clair, Carley Mcalister, Chinemerem P. Ogbu, Jessica Smolenske, Randall J. Cohrs, Rushika Perera

Nebraska Center for Virology: Faculty Publications

Due to the COVID-19 pandemic and multiple devastating forest fires, the 2020 meeting of the Rocky Mountain Virology Association was held virtually. The three-day gathering featured talks describing recent advances in virology and prion research. The keynote presentation described the measles virus paradox of immune suppression and life-long immunity. Special invited speakers presented information concerning visualizing antiviral effector cell biology in mucosal tissues, uncovering the T-cell tropism of Epstein-Barr virus type 2, a history and current survey of coronavirus spike proteins, a summary of Zika virus vaccination and immunity, the innate immune response to flavivirus infections, a discussion concerning prion …

Chlorovirus Pbcv-1 Multidomain Protein A111/114r Has Three Glycosyltransferase Functions Involved In The Synthesis Of Atypical N-Glycans, Eric Noel, Anna Notaro, Immacolata Speciale, Garry A. Duncan, Cristina De Castro, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

The structures of the four N-linked glycans from the prototype chlorovirus PBCV-1 major capsid protein do not resemble any other glycans in the three domains of life. All known chloroviruses and antigenic variants (or mutants) share a unique conserved central glycan core consisting of five sugars, except for antigenic mutant virus P1L6, which has four of the five sugars. A combination of ge- netic and structural analyses indicates that the protein coded by PBCV-1 gene a111/114r, conserved in all chloroviruses, is a glycosyltransferase with three putative domains of approximately 300 amino acids each. Here, in addition to in silico sequence …

Strategies Targeting Hemagglutinin As A Universal Influenza Vaccine, Brianna L. Bullard, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Influenza virus has significant viral diversity, both through antigenic drift and shift, which makes development of a vaccine challenging. Current influenza vaccines are updated yearly to in- clude strains predicted to circulate in the upcoming influenza season, however this can lead to a mismatch which reduces vaccine efficacy. Several strategies targeting the most abundant and im- munogenic surface protein of influenza, the hemagglutinin (HA) protein, have been explored. These strategies include stalk-directed, consensus-based, and computationally derived HA immunogens. In this review, we explore vaccine strategies which utilize novel antigen design of the HA protein to improve cross-reactive immunity for development …

Zika Virus Infection Induces Endoplasmic Reticulum Stress And Apoptosis In Placental Trophoblasts, Philma Glora Muthuraj, Prakask K. Sahoo, Madison Kraus, Taylor Bruett, Arun S. Annamalai, Aryamav Pattnaik, Asit K. Pattnaik, Siddappa N. Byrareddy, Sathish Kumar Natarajan

Nebraska Center for Virology: Faculty Publications

Zika virus (ZIKV) infection to a pregnant woman can be vertically transmitted to the fetus via the placenta leading to Congenital Zika syndrome. This is characterized by microcephaly, retinal defects, and intrauterine growth retardation. ZIKV induces placental trophoblast apoptosis leading to severe abnormalities in the growth and development of the fetus. However, the molecular mechanism behind ZIKV-induced apoptosis in placental trophoblasts remains unclear. We hypothesize that ZIKV infection induces endoplasmic reticulum (ER) stress in the trophoblasts, and sustained ER stress results in apoptosis. HTR-8 (HTR-8/SVneo), a human normal immortalized trophoblast cell and human choriocarcinoma-derived cell lines (JEG-3 and JAR) were …

Of Pigs And Men: The Best-Laid Plans For Prevention And Control Of Swine Fevers, Jishu Shi, Lihua Wang, David Scott Mcvey

School of Veterinary and Biomedical Sciences: Faculty Publications

John Steinbeck drew the title of his novel “Of Mice and Men” from a line in a Robert Burns poem “To a mouse”: “The best-laid plans of mice and men/Go often awry.” Unlike John Steinbeck who used the title to mirror the characters who were struggling during the Great Depression to the mouse whose nest was accidentally destroyed by the poet (Burns 1785), we chose this line to emphasize that the best-laid plan can go wrong in infectious disease control and prevention. Here, we will discuss the contributing factors behind the global successes and failures in the prevention and control …

Special Issue: Shiga Toxin-Producing Escherichia Coli, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

Globally, Shiga toxin-producing Escherichia coli (STEC) is an important cause of diarrheal disease, most notably hemorrhagic colitis, and post-diarrheal sequela, such as hemolytic-uremic syndrome (HUS) [1]. Cattle are a major reservoir of STEC, with approx- imately half of the cases in humans attributable to foodborne exposure [2]. Prevention of human illness has mainly been through food safety measures [2]. Despite extensive research, no other generally accepted and effective preventive measures or therapies for STEC infections in human patients are available [3]. Many questions remain about STEC virulence factors, pathogenesis, detection, and other aspects that necessitate a continua- tion of basic …

Inhibition Of Zika Virus Replication By G-Quadruplex-Binding Ligands, Prativa Majee, Aryamav Pattnaik, Bikash R. Sahoo, Uma Shankar, Asit K. Pattnaik, Amit Kumar, Debasis Nayak

School of Veterinary and Biomedical Sciences: Faculty Publications

Zika virus (ZIKV), a mosquito-transmitted Flavivirus, emerged in the last decade causing serious diseases and affecting human health globally. Currently, no licensed vaccines or antivirals are available to combat ZIKV, although several vaccine candidates are in the pipeline. In recent years, the presence of non-canon- ical G-quadruplex (GQ) secondary structures in viral genomes has ignited significant attention as potential targets for anti- viral strategy. In this study, we identified several novel conserved potential GQ structures by analyzing published ZIKV genome sequences using an in-house algorithm. Bio- physical and biochemical analysis of the RNA sequences con- taining these potential GQ sequences …

A New Mathematical Theory For The Dynamics Of Large Tumor Populations, A Potential Mechanism For Cancer Dormancy & Recurrence And Experimental Observation Of Melanoma Progression In Zebrafish, Adeyinka A. Lesi

Dissertations and Theses

Cancer, a family of over a hundred disease varieties, results in 600,000 deaths in the U.S. alone. Yet, improvements in imaging technology to detect disease earlier, pharmaceutical developments to shrink or eliminate tumors, and modeling of biological interactions to guide treatment have prevented millions of deaths. Cancer patients with initially similar disease can experience vastly different outcomes, including sustained recovery, refractory disease or, remarkably, recurrence years after apparently successful treatment. The current understanding of such recurrences is that they depend on the random occurrence of critical mutations. Clearly, these biological changes appear to be sufficient for recurrence, but are they …

Molecular And Genetic Studies On A Sipd/Ipad-Related Virulence Spike Protein From Immune-Suppressive Particles Of A Drosophila Parasitoid, Carlo Miguel A. Sevilla

Dissertations and Theses

Parasitoid wasps are effective biological control agents that have evolved intricate host immune suppression strategies to overcome host immune defenses. The most important anti-parasite defense mechanism is encapsulation, where the host’s blood cells surround the wasp egg. In the Drosophila/Leptopilina host-parasitoid system, extracellular vesicles (EVs) are oviposited along with the wasp egg. The EVs possess spikes and contain hundreds of proteins, some of which enable wasp eggs to escape encapsulation by changing the morphology and function of hemocytes, or killing them. Previous studies have identified an abundant surface/spike protein (SSp40) from Leptopilina heterotoma EVs. While p40, a predicted …

Regulation Of Actin Assembly, Mechanics, And Structure By Intracellular Environmental Factors, Nicholas Castaneda

Electronic Theses and Dissertations, 2020-2023

The assembly, mechanics, and structure of actin cytoskeleton are critical for eukaryotic cellular processes such as structural support, cellular motility, and intracellular transport. Actin assembly occurs in crowded intracellular environments containing many ions and macromolecules. While the individual roles of cation and crowding on actin assembly and mechanics are well established, how the combined cation and crowding effects modulate the formation, mechanics and structural transitioning of actin filaments and bundles are not fully understood. Here, we investigate the impacts of various cation and crowded environments on the bending stiffness, length, organization, secondary structure, and kinetics of actin filaments and bundles. …