Biochemistry, Biophysics, and Structural Biology Commons^™

The Development Of Skeletal Muscle In Young Horses: An Ultrasonography And Satellite Cell Approach, Emma K. Lavigne

Honors Scholar Theses

Muscle growth in young horses is characterized by an increase in muscle cross-sectional area, which can be accomplished through the activation and differentiation of satellite cells. Satellite cells can be stimulated or inhibited in response to different cytokines and growth factors and are key mediators of muscle hypertrophy and regeneration. The aim of this study was to investigate the growth of the longissimus dorsi (LD) muscle in horses under 5 years of age and to obtain preliminary data on satellite cell behavior in foals. The area, width, height, and subcutaneous fat were measured using ultrasonography at 6-month increments over the …

Efficient In Vitro Development Of Photoreceptors From Human Pluripotent Stem Cells, Joseph C. Reynolds

Dissertations, Masters Theses, Capstones, and Culminating Projects

Degeneration of the rod and cone photoreceptors in the human retina is among the most common causes of blindness. Replacing these damaged photoreceptors may help to restore vision. Repairing the damaged retina relies on the insertion of new, healthy cells. Embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are two possible sources of photoreceptors to restore vision. Previous data shows that human ES cells and iPS cells can be differentiated into photoreceptors and transplanted into the eye to restore some vision. However, this process is inefficient, and costly. Here, we show a new method for inducing photoreceptor production …

Measuring Single Cell Responses To Lapatinib In A Heterogeneous Population, Preety Priya

Dissertations & Theses (Open Access)

Cancer is notonedisease butasaga of diseases and is the outcome of disturbed homeostasis in the normal cells due to the deregulation of its genetic makeup. With advent of technologies thatallowdetailed molecular characterizationoftumors, targeted therapies have emerged as a more promising and specific mode of treatment. However, a major challenge with targeted therapy is the acquired resistance in the cancer cells to these therapies, quite often very rapidly in the course of a few months. One of the major targets in cancer has been the EGFR/ErbB2 network in breast and other cancer types. Prior work from our lab and others have …

Dna Polymerase Θ (Polq) And The Cellular Defense Against Dna Damage, Matthew J. Yousefzadeh

Dissertations & Theses (Open Access)

In mammalian cells, DNA polymerase θ (POLQ) is an unusual specialized DNA polymerase whose in vivo function is under active investigation. The protein is comprised of an N-terminal helicase-like domain, a C-terminal DNA polymerase domain, and a large central domain that spans between the two. This arrangement is also found in the Drosophila Mus308 protein, which helps confer resistance to DNA interstrand crosslinking agents. Homologs of POLQ and Mus308 are found in eukaryotes, including plants, but a comparison of phenotypes suggests that not all of these genes are functional orthologs. Flies with defective Mus308 are sensitive to DNA interstrand crosslinking …

Investigating The Roles Of P63 And P73 Isoforms To Therapeutically Treat P53-Altered Cancers, Avinashnarayan Venkatanarayan

Dissertations & Theses (Open Access)

Investigating the roles of p63 & p73 isoforms to therapeutically treat

p53-altered cancers

Avinashnarayan Venkatanarayan, M.S.

Supervisory Professor: Elsa R. Flores, Ph.D.

The TP53 tumor suppressor is mutated in approximately 50% of human cancers rendering cancer therapies ineffective. p53 reactivation suppresses tumor formation in mice. However, this strategy has proven difficult to implement therapeutically. An alternate approach to overcome p53 loss is to manipulate the p53-family members, p63 and p73, which interact and share structural similarities to p53. p63 and p73, unlike p53 are less frequently mutated and have two major isoforms with distinct functions …

The Effect Of High Terperature On Mating: Developmental Buffering Of S. Cerevisiae To The Environment, Sarah Hosie

Renée Crown University Honors Thesis Projects - All

In Saccharomyces cerevisiae, cellular polarization is an essential structural and functional aspect of growth and development. It is responsible for yielding and maintaining cellular asymmetry, and allows for cells to function. Mating in S. cerevisiae is a process that incorporates cell-to-cell signaling, signal transduction, cellular polarization, plasmogamy, karyogamy, and many other cellular processes. Each of these steps is mediated by a myriad of signaling proteins that are involved in a signaling cascade that is regulated by both extracellular and intracellular signals. Much is known about the mating process and pathway in S. cerevisiae. However, this project aimed to …

Role Of Non-Muscle Myosin Ii And Calcium In Zebrafish Midbrain-Hindbrain Boundary Morphogenesis, Srishti Upasana Sahu

Theses and Dissertations

Elucidating the molecular mechanisms that play a role in cellular morphogenesis is critical to our understanding of brain development and function. The midbrain-hindbrain boundary (MHB) is one of the first folds in the vertebrate embryonic brain and is highly conserved across species. We used the zebrafish MHB as a model for determining the molecular mechanisms that regulate these cell shape changes. Cellular morphogenesis is tightly regulated by signaling pathways that rearrange the cytoskeleton and produce mechanical forces that enable changes in cell and tissue morphology. The generation of force within a cell often depends on motor proteins, particularly non-muscle myosins …

Regulation Of Cell Adhesion By The Ferm Proteins, Ptpn14 And Merlin, Patty Dimarco Hewitt

Dissertations & Theses (Open Access)

Cell-cell adhesion is critical for the control of tissue organization and homeostasis. A family of proteins that regulate cell-cell adhesions is the FERM (4.1 protein, Ezrin, Radixin, Moesin) domain-containing proteins.One FERM domain protein, the non-receptor tyrosine phosphatase PTPN14, is mutated or deleted in several human cancers suggesting that it may be involved in tumor development and/or progression. Additionally, the loss of the FERM domain protein Merlin is associated with tumor development and metastasis.Both PTPN14 and Merlin have been shown to localize and possibly regulate adherens junction (AJ) functions. This work sought to determine if …

Overexpression And Gene Profiling Of Asparagine Synthetase In Hybrid Poplar, Kristopher Murray

Renée Crown University Honors Thesis Projects - All

Plants with polysaccharide-rich secondary cell walls have great potential as a source of carbohydrates for bioethanol production. However, the presence of phenolic lignin inhibits the isolation of bioethanol precursors cellulose and hemicellulose from the secondary cell wall. Recent studies have linked nitrogen availability to secondary cell wall development and composition, making nitrogen metabolism genes an interesting target in the improvement of plant cell walls for biofuels production. Plants use a nitrogen assimilation pathway to convert inorganic nitrogen sources into organic sources, included amino acids, which play key roles in metabolism and cell wall development. Asparagine synthetase (AS), a key enzyme …

Characterization Of Ghrelin O-Acyltransferase Active Site, Leslie Patton

Renée Crown University Honors Thesis Projects - All

Ghrelin, first discovered in 1999, is a 28-amino acid peptide hormone involved in the regulation of appetite, insulin secretion and sensitivity, and many neurological effects such as learning, memory, and depression.^1-6 Ghrelin has been identified to have a unique posttranslational octanoylation carried out by the enzyme ghrelin O-acyltransferase (GOAT). This distinctive modification is a point of interest in studying GOAT whereby blocking the acylation of the ghrelin could potentially halt the activity of the peptide hormone and provide a means of treating obesity, diabetes, and other diseases affected by ghrelin levels. The duration of my project involved working …

The Characterization Of Amyloid Fibrils And Novel Synthetic Heparin-Binding Peptides Binding To Cell Surfaces, Nicole Marie Hackenbrack

Chancellor’s Honors Program Projects

No abstract provided.

Inducing And Characterizing M2c Macrophages At A Non-Degradable Implant In Vivo, Geoffrey David Keeler

Graduate Theses and Dissertations

The implantation of biomaterials in the body leads to a reaction known as the foreign body response (FBR) which leads to the eventual encapsulation of the biomaterial. This encapsulation proves to be detrimental to certain biomaterials, such as implanted glucose sensors, which rely on interacting with the extracellular space for proper function. Altering the FBR has become of interest in an effort to increase the longevity and integration of biomaterials. One strategy for altering the FBR is by targeting the macrophage, shown to play an important role in the FBR. In this work, the microdialysis sampling technique was used to …

Impacts Of Micrornas On Skeletal Muscle Protein Synthesis And Mitochondrial Quality, David Lee

Graduate Theses and Dissertations

microRNA (miRNA) post-transcriptional modification is becoming a well-established mechanism for controlling mRNA translation. microRNAs -1, -133, and -206 are under the control of skeletal muscle promoters and affect muscle plasticity and metabolic health. A detailed review on the generation and processing of miRNAs with a view to skeletal muscle brings up intriguing connections in the transcriptional connections between multiple miRNAs. Additionally, exciting new research has defined a role of miRNAs in skeletal muscle mitochondria showing an additional, direct link to metabolic function. Multiple investigations in models of exercise, aging, hypertrophy, and injury have shown how these interventions can affect miRNA …

Local Modulation And Measurement Of Macrophage-Derived Bioactive Proteins From Implanted Biomaterials In Rat, Geetika Bajpai

Graduate Theses and Dissertations

Fibrosis around the implanted medical devices is a severe problem that can plague long-term device reliability. Activation of macrophage phenotype (macrophage polarization) has emerged as a new and possible means for reducing fibrosis in the fields of biomaterials and regenerative medicine. Macrophages are phagocytic cells that respond to microenvironmental cues that direct their phenotype. Macrophage activation has been widely studied in mouse and human in the context of tumor biology, yet little information is available regarding how macrophage activation could be used in a biomaterials context. Further, rats rather than mice are the common subjects in biomaterials experiments. A significant …

A Lipopolysaccharide-Induced Dna-Binding Protein For A Class Ii Gene In B Cells Is Distinct From Nf-Kappa B, Ellen M. Gravallese, Mark R. Boothby, Cynthia M. Smas, Laurie H. Glimcher

Ellen M. Gravallese

Class II (Ia) major histocompatibility complex molecules are cell surface proteins normally expressed by a limited subset of cells of the immune system. These molecules regulate the activation of T cells and are required for the presentation of antigens and the initiation of immune responses. The expression of Ia in B cells is determined by both the developmental stage of the B cell and by certain external stimuli. It has been demonstrated previously that treatment of B cells with lipopolysaccharide (LPS) results in increased surface expression of Ia protein. However, we have confirmed that LPS treatment results in a significant …

Translesion Synthesis And Mutations: On The Mutagenic Properties Of The Two Dna Lesions, 8-Oxo-G And Pt-Gg, And The Functions Of Y-Family Dna Polymerases And Rev3l On The Bypass Of Each Of The Dna Lesions In Mammalian Cells, Lizhen Guo

Electronic Thesis and Dissertation Repository

I studied the capabilities of the two DNA lesions 8-oxo-guanine and cisplatin intrastrand crosslinked 1,2-d(GpG) or Pt-GG to cause mutations in mammalian cells. Using isogenic cell lines generated from mice with selective gene knockouts of distinct DNA polymerases as models, I deduced the biological functions of the translesion DNA polymerases Pol eta, Pol kappa, Pol iota, Rev1 and Rev3L on bypassing each of the lesions 8-oxo-G and Pt-GG. My study takes advantage of the Next Generation Sequencing (NGS) technology to determine mutagenic effects of the DNA lesions in vivo and effects of translesion DNA polymerases on bypassing the lesions. Through …

Analysis Of Chd Remodelers During Development: A Tale In Two Organisms, Brett Bishop

Open Access Dissertations

The correct development of different organisms requires the precise timing of genes important for development transitions. Organisms have recruited ATP-dependent chromatin remodelers to ensure the correct timing of gene expression during developmental transitions. Here I show how different CHD ATP-dependent chromatin remodelers regulate developmental transitions of different organisms. I show that PICKLE not only promotes H3K27me3 during development to repress developmental genes but also is targeted to these genes. The association of PICKLE to these genes suggests that both repression and H3K27me3 levels is a direct action of PICKLE on these loci. Using zebrafish as a model system, I show …

Investigating Notch Signaling And Sequential Segmentation In The Fairy Shrimp, Thamnocephalus Platyurus, Sara Izzat Khalil

Senior Theses and Projects

Segmentation is a key feature of arthropod diversity and evolution. In the standard model for arthropod development, Drosophila melanogaster, segments develop simultaneously by a progressive subdivision of the embryo. By contrast, most arthropods add segments sequentially from a posterior region called the growth zone and in a manner similar to vertebrates.

Recent work, mainly focused on insects, suggests that Notch signaling might play a role in arthropods that segment sequentially. These studies document a potential regulatory similarity between sequentially segmenting arthropods and vertebrates. In vertebrates, somite formation involves a molecular oscillator that functions as a pacemaker, driving periodic expression …

Redox Regulation Of Ras Proteins In Dictyostelium Discoideum, Boris Castillo Chabeco

FIU Electronic Theses and Dissertations

Reactive oxygen species are a normal consequence of life in an aerobic environment. However when they deviate from the narrow permissible range in cells, oxidative damage can occur. Dictyostelium discoideum is a model organism ideal for the study of cell signaling events such as those affected by oxidative stress. It was previously shown that Ras signaling in Dictyostelium is affected by genetic inactivation of the antioxidant enzyme Superoxide dismutase C (SodC) and in vitro data suggests that the NKCD motif of Ras is the redox target of superoxide.

The main objective of this project was to determine the mechanism of …

Relationship Between Heat-Labile Enterotoxin Secretion Capacity And Virulence In Wild Type Porcine-Origin Enterotoxigenic Escherichia Coli Strains, Prageeth Wijemanne, Jun Xing, Emil M. Berberov, David B. Marx, David H. Francis, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

Heat-labile enterotoxin (LT) is an important virulence factor secreted by some strains of enterotoxigenic Escherichia coli (ETEC). The prototypic human-origin strain H10407 secretes LT via a type II secretion system(T2SS). We sought to determine the relationship between the capacity to secrete LT and virulence in porcine-origin wild type (WT) ETEC strains. Sixteen WT ETEC strains isolated from cases of severe diarrheal disease were analyzed by GM1ganglioside enzyme- linked immunosorbent assay tomeasure LT concentrations in culture supernatants. All strains had detectable LT in supernatants by 2 h of culture and 1 strain, which was particularly virulent in gnotobiotic piglets (3030-2), had …

Environmental Microbes And Uveitis: Is Microbial Exposure Always Bad?, Chandirasegaran Massilamany, A. Gangaplara, J. Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

The eye generally is considered to be an immune-privileged organ, but this notion is being increasingly challenged as ocular antigens can be expressed in the generative lymphoid organs, resulting in attainment of self-tolerance. What triggers a break in this tolerant state is a fundamental question in autoimmunity research. The general belief is that exposure to environmental microbes can break self-tolerance in genetically susceptible individuals, leading to the induction of autoimmune responses. The molecular mimicry hypothesis has been proposed as one major mechanistic, pathway through which microbes, by generating crossreactive immune responses, can induce ocular damage of the kind that might …

Promoting Genome Stability Via Multiple Dna Repair Pathways, Scott Cukras

USF Tampa Graduate Theses and Dissertations

Maintaining genome integrity is indispensible for cells to prevent and limit accruement of deleterious mutations and to promote viable cell growth and proliferation. Cells possess a myriad of mechanisms to detect, prevent and repair incurred cellular damage. Here we discuss various proteins and their accompanying cellular pathways that promote genome stability. We first investigate the NEDD8 protein and its role in promoting homologous recombination repair via multiple Cullin E3 ubiquitin ligases. We provide specific mechanisms through which, UBE2M, an E2 conjugating enzyme, neddylates various Cullin ligases to render them catalytically active to degrade their substrates by the proteasome. We show …

Theoretical Investigation Of Intra- And Inter-Cellular Spatiotemporal Calcium Patterns In Microcirculation, Jaimit B. Parikh

FIU Electronic Theses and Dissertations

Microcirculatory vessels are lined by endothelial cells (ECs) which are surrounded by a single or multiple layer of smooth muscle cells (SMCs). Spontaneous and agonist induced spatiotemporal calcium (Ca²⁺) events are generated in ECs and SMCs, and regulated by complex bi-directional signaling between the two layers which ultimately determines the vessel tone. The contractile state of microcirculatory vessels is an important factor in the determination of vascular resistance, blood flow and blood pressure. This dissertation presents theoretical insights into some of the important and currently unresolved phenomena in microvascular tone regulation. Compartmental and continuum models of isolated EC …

Clique Topology Reveals Intrinsic Geometric Structure In Neural Correlations, Chad Giusti, Eva Pastalkova, Carina Curto, Vladimir Itskov

Department of Mathematics: Faculty Publications

Detecting meaningful structure in neural activity and connectivity data is challenging in the presence of hidden nonlinearities, where traditional eigenvalue-based methods may be misleading. We introduce a novel approach to matrix analysis, called clique topology, that extracts features of the data invariant under nonlinear monotone transformations. These features can be used to detect both random and geometric structure, and depend only on the relative ordering of matrix entries. We then analyzed the activity of pyramidal neurons in rat hippocampus, recorded while the animal was exploring a 2D environment, and confirmed that our method is able to detect geometric organization using …

Physiological Function Of Fus: An Rna Binding Protein In Motor Neuron Disease, Liuqing Yang

Theses and Dissertations--Molecular and Cellular Biochemistry

FUS is an RNA binding protein implicated in the motor neuron disease— amyotrophic lateral sclerosis (ALS, also called Lou Gehrig’s disease). ALS is a fatal neurodegenerative disease characterized by progressive motor neuron death. Mutations in the FUS gene cause about 4% of familial ALS (FUS ALS). Mutated FUS protein mislocalizes from the motor neuron nucleus to the cytoplasm and forms inclusions in the cytoplasm. It is unclear how FUS mislocalization induces motor neuron dysfunction and degeneration. This dissertation research was designed to investigate the physiological functions of FUS in the nucleus, with a purpose to shed light on the pathogenesis …

Epigenetic Role Of Ptip In Mouse Spermatogenesis, Chengjing Liu

Theses, Dissertations and Capstones

In mammals, spermatogenesis is a biological process inside the testis to produce spermatozoa from spermatogonia. This process is governed by both genetic and epigenetic mechanisms and thus is a powerful system for epigenetic research. Methylation of histone 3 lysine 4 (H3K4) is an epigenetic mark, which has been found to be dynamically modulated in mouse male germ cells during spermatogenesis. Pax2 Transactivation domain Interaction Protein (PTIP) has been recently identified as part of a H3K4 methyltransferase complex. In this study, I hypothesize that PTIP is an essential epigenetic regulator in mouse spermatogenesis. To test this hypothesis, I first established a …

Nitric Oxide Generating/Releasing Materials, Honying Liang, Parimala Nacharaju, Adam J. Friedman, Joel Friedman

Dermatology Faculty Publications

Harnessing the impressive therapeutic potential of nitric oxide (NO) remains an ongoing challenge. This paper describes several of the current strategies both with respect to the underlying chemistry and physics and to the applications where they have shown promise. Included in this overview are molecular systems such as NONOates that release NO through chemical reactions and delivery vehicles such as nanoparticles that can generate, store, transport and deliver NO and related bioactive forms of NO such as nitrosothiols. Although there has been much positive movement, it is clear that we are only at the early stages of knowing how to …

Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo

Open Access Dissertations

Biologists use mechanistic explanations to understand behaviors of the immense complexity of molecular and cellular systems. In undergraduate biology courses, students are expected to explain molecular and cellular mechanisms, but teaching this skill presents many challenges due to the highly abstract, intangible nature of the cellular world, the influence of everyday language, and the tendency of students to overestimate how much they can explain. Therefore, across three studies this dissertation addresses these obstacles to teach undergraduate biology students to explain molecular and cellular mechanisms. ^ The first step was to model how biology experts explain molecular and cellular mechanisms, and …

Differential Protein Expression During Tail Regeneration Of Anolis Carolinensis, Victor Hong, Benjamin Thornton

Research in Biology

Some invertebrate and vertebrate species have the ability to regenerate a lost limb. The lizard species are unique in that they can autotomize their tails and regrow them back. In this study, the proteomic change occurring within the regenerating tail of Anolis carolinensis (Green anole) during 72 h period was examined. We ran 2-dimension electrophoresis to separate the proteins and utilized SameSpots software to find 6 different spots that had altered expression of protein. Within those spots, proteins involved in immunity, energetics, and protein folding and degradation were identified. The proteins that were up-regulated were transferrin, nucleotide-binding domain of the …

Proteasome Inhibition As A Potential Anti-Breast Cancer Therapy: Mechanisms Of Action And Resistance-Reversing Strategies, Rahul Rajesinh Deshmukh

Wayne State University Dissertations

AMPK activation and Ubiquitin Proteasome System (UPS) inhibition have gained great attention as therapeutic strategies for the treatment of certain types of cancers. While AMPK serves as a master regulator of cellular metabolism, UPS regulates protein homeostasis. Although the crosstalk between them is suggested, the relationship between these two important pathways is not very clear. We observed that proteasome inhibition leads to AMPK activation in human breast cancer cells. We report that a variety of proteasome inhibitors activate AMPK in all of the tested cancer cell lines. Our data using Liver Kinase B1 (LKB1)-deficient cancer cells suggests that proteasome inhibitor-induced …