Molecular Biology Commons^™

Exploring Variability Of The Cg18562578 Methylquant Assay For The Forensic Discrimination Of Monozygotic Twins, Sydney E. Arnold

Student Theses

Monozygotic (MZ) twins possess identical DNA sequences, posing a problem for forensic scientists, as they are incapable of distinguishing MZ twins from each other using traditional DNA identification methods. However, the epigenomes of MZ twins will differ and might be used for their forensic discrimination. Here, we explored the variability of an assay previously developed by our laboratory that showed high discrimination potential for MZ twins using buccal swab DNA, cg18562578 MethylQuant. We measured precision at each step: bisulfite conversion, nested PCR, and qPCR, reproducibility, and repeatability. DNA methylation ratios were compared between two analysts carrying each step using the …

Cg18562578 Methylquant Assay For The Discrimination Of Monozygotic Twins, Amber P. Chauca

Student Theses

Monozygotic (MZ) twins have identical DNA, making traditional profiling methods insufficient in their discrimination. However, MZ twins can be differentiated by their levels of DNA methylation. Our research group previously developed a methodology to detect cg18562578 DNA methylation levels in MZ twins based on a two- step PCR approach and a cg18562578 MethylQuant Assay. That study generated data for only 64% of the samples it investigated, and showed a discrimination power of 77% to discriminate between MZ twins. Here, we used the same methodology but a different approach to determine DNA methylation in 73 previously unsuccessful twin pairs. We diluted …

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

Dissertations and Theses

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

Mucin 5ac Modulates Cancer-Associated Fibroblast Heterogeneity Through Epigenetic Regulation, Rachel J. Kehrberg

Theses & Dissertations

Pancreatic cancer is characterized by a stroma component that comprises up to 90% of the tumor. Cancer-associated fibroblasts (CAFs) are a significant component of the stroma and contribute to cancer pathobiology through the secretion of extracellular matrix, growth factors, metabolites, and cytokines. CAFs are a highly heterogeneous population derived from various precursors, including adipose-derived and bone marrow- derived mesenchymal stem cells (AD-MSCs, BM-MSCs) and pancreatic stellate cells (PSCs). In this dissertation, we examine how mucin 5ac (Muc5ac) mediates the maturation of AD-MSCs, BM-MSCs, and PSCs into CAFs and the heterogeneity between CAFs derived from these various precursors. Muc5ac promotes the …

Epigenetic Modification As A Therapeutic Target In Brafv600e-Mutated Metastatic Colorectal Cancer, Hey Min Lee

Dissertations and Theses (Open Access)

Patients with BRAF^V600E-mutated metastatic colorectal cancer (mCRC) experience a worse prognosis and demonstrate only a 5% response rate to BRAF inhibitor treatment. In this study, adaptive resistance, and a potential combination of standard therapies in BRAF^V600E CRC were unveiled. Intriguingly, a robust association of BRAF^V600E mutation and DNA hypermethylation suggests this is a unique subgroup harboring aberrant epigenetic phenotype. Firstly, DNA methyltransferase (DNMT) inhibitor treatment induced profound DNA hypomethylation in vivo, but minimal change in gene expression due to adaptive elevation of the repressive histone methylation, H3K27me3, leading to compensatory suppression of key tumor suppressor genes, …

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …

Migratory Material: Epigenetics & Weaving At The Us-Mexico Border, Valerie Navarrete

Masters Theses

Discourse often sutures the body shut, disallowing representations of identity to outgrow sociopolitical interests. This issue may originate from borders, but also from the unnamable pathology that generational colonial trauma transmits to the mind, body, and environment. Without a direct form of translatability, this thesis proposes a new materialism that deviates from any object-oriented ontology. Untethered and intra-active, epigenetics and weaving represent objects that transform typical ways of knowing and seeing. Their sensitivity to the environment, in addition to their mobility across generations of time, broaden the spatiotemporal loci of the body and its embodiment. Proposing new materials that expand …

New Dna Repair And Demethylation Functions In Uracil Dna Glycosylase Superfamily, Chenyan Chang

All Dissertations

Uracil-DNA glycosylase (UDG) superfamily, which consists of several groups of enzymes that recognize the damaged DNA bases and initiate the base excision repair (BER) pathway, is most important in dealing with DNA deamination and other base modifications. Thymine DNA glycosylase (TDG), which belongs to family 2 in the UDG superfamily, is able to specifically recognize and cleave the 5-methylcytosine (mC) oxidative derivatives including 5-formylcytosine (fC), 5-carboxylcytosine (caC), 5-hydromethyluracil (hmU) caused by active demethylation or DNA damage. My dissertation work is mainly focused on the fC and caC glycosylase activity within UDG superfamily. Chapter 1 is a general introduction to the …

Molecular And Systemic Epigenetic Inheritance: Integrating Development, Genetics, And Evolution, Robert Lickliter, David S. Moore

Pitzer Faculty Publications and Research

Currently, a central problem for theoretical biology is the integration of development with genetics and evolutionary theory. Through the late 20^th century, biologists held that animals resemble their ancestors strictly because of the transgenerational transmission of DNA. This view effectively wrote development out of evolutionary biology. However, many molecular and developmental biologists now understand that phenotypes—anatomical, physiological, and behavioral traits—are not determined by genes (i.e., DNA segments) alone; instead, they emerge epigenetically from developmental processes involving co-acting genetic factors, environmental factors, molecular epigenetic factors, and other non-genetic factors within organisms’ bodies. This insight forces a rethinking of biological inheritance. …

Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson

College of Graduate Studies: Theses & Dissertations

Epigenetics is the study of molecular modification of a genome without changing its base pairs. The most studied type of epigenetic mechanism is DNA methylation, which is capable of turning a gene “on” or “off.” Epigenetic potential is the capacity to which an individual can have methylation on its genome. The more CpGs available, the greater the epigenetic potential. In invasive species, genetic variation has been observed to be paradoxical: not much of it exists on a genomic level, but epigenetically, phenotypic variation can occur. The focus on shift in gene expression in this study is on Toll-Like Receptor 4 …

An Investigation Of Epigenetic Mechanisms Driving The Biology Of Head And Neck Squamous Cell Carcinoma, Scot Carson Callahan

Dissertations and Theses (Open Access)

Head and neck squamous cell carcinoma (HNSCC) is the 6th most common cancer worldwide and is associated with significant morbidity and mortality. To date, the majority of work in the field has focused on genomic alterations such as mutations and copy number alterations. However, the clinical success of targeted therapies that exploit known genomic alterations, such as EGFR mutations, has remained mixed. Over the past decade, the importance of epigenetic regulators has come to the forefront, with the realization that many of these genes are mutated in cancer. Despite this realization, the role of epigenetics in regulating tumorigenesis, progression and …

Plant Homeodomain Finger Protein 20 (Phf20) And Its Homolog Phf20 Like 1 (Phf20l1) Define Two Distinct Non-Specific Lethal (Nsl) Complexes, Hieu Van, Hieu T. Van

Dissertations and Theses (Open Access)

Plant Homeodomain Finger Protein 20 (PHF20) and its homolog PHF20 Like 1 (PHF20L1) are known subunits of the Non-Specific Lethal (NSL) complex, which acetylates lysine residues on histone H4 and regulates gene expression. The current model assumes that PHF20 and PHF20L1 are present together in the NSL complex, although it has never been tested. Performing extensive biochemical analysis, we observed that PHF20 and PHF20L1 were exclusively and independently associated with the NSL complex. Our protein domain analysis showed that the C-termini of PHF20 and PHF20L1 are crucial for their interactions with the respective complexes. Furthermore, enrichment sites of PHF20 and …

Enhancing Therapeutic Approaches For Melanoma Patients Targeting Epigenetic Modifiers., Maria Gracia-Hernandez, Zuleima Munoz, Alejandro Villagra

Biochemistry and Molecular Medicine Faculty Publications

Melanoma is the least common but deadliest type of skin cancer. Melanomagenesis is driven by a series of mutations and epigenetic alterations in oncogenes and tumor suppressor genes that allow melanomas to grow, evolve, and metastasize. Epigenetic alterations can also lead to immune evasion and development of resistance to therapies. Although the standard of care for melanoma patients includes surgery, targeted therapies, and immune checkpoint blockade, other therapeutic approaches like radiation therapy, chemotherapy, and immune cell-based therapies are used for patients with advanced disease or unresponsive to the conventional first-line therapies. Targeted therapies such as the use of BRAF and …

Discovery Of Novel Ubiquitin- And Methylation-Dependent Interactions Using Protein Domain Microarrays, Jianji Chen

Dissertations and Theses (Open Access)

Post-translational modifications (PTMs) drive signal transduction by interacting with "reader" proteins. Protein domain microarray is a high throughput platform to identify novel readers for PTMs. In this dissertation, I applied two protein domain microarrays identifying novel readers for histone H2Aub1 and H2Bub1, and H3TM K4me3. Ubiquitinations of histone H2A at K119 (H2Aub1) and histone H2B at K120 (H2Bub1) function in distinct transcription regulation and DNA damage repair pathways, likely mediated by specific "reader" proteins. There are only two H2Aub1-specific readers identified and no known H2Bub1-specific readers. Using a ubiquitin-binding domain microarray, I discovered the phospholipase A2-activating protein (PLAA) PFU domain …

Initial And Advanced Stages Of Microbiota Establishment Within The Tsetse Fly, Miguel Eduardo Medina Munoz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Symbiosis is a long-term physical association between two or more species, although little is known regarding its evolutionary origins, particularly at the genetic level. Tsetse flies are the vector of African trypanosomes, causative agents of Human and Animal African Trypanosomiases. Tsetse provide an ideal model for studying initial and advanced stages of symbiosis. Tsetse have a simple digestive tract microbiota primarily consisting of two bacteria; the ancient mutualist Wigglesworthia glossinidia and the recently acquired Sodalis glossinidius. This work presents a chronological study in evolutionary terms of the history of a microbial-insect association. First, I present concepts on symbiosis and …

Discrimination Of Monozygotic Twins Using Dna Methylation Levels Of One Cpg Site At Chromosome 3, Dino O. Robinson

Student Theses

Conventional STR typing, commonly used in forensics for human identification, poses a problem in criminal cases and paternity disputes involving monozygotic (MZ) twins because they share identical DNA sequences. To date, no routine method is available in forensics to differentiate between individuals of MZ pairs. Recently, epigenetic methods measuring differential DNA methylation patterns have been applied to MZ twin differentiation. In this study, we investigated the potential to identify MZ twins using a previously identified DNA methylation site in chromosome 3, cg18562578, in a sample of 129 MZ and 37 dizygotic (DZ) twin pairs. We used bisulfite converted saliva DNA …

Understanding The Molecular And Cellular Functions Of Odd-Skipped Related 1 In Outflow Tract Development, Menglan Xiang

Theses and Dissertations

The cardiac outflow tract (OFT) is a transient conduit that connects the embryonic heart chambers to the vascular network. Transcription factor Osr1 promotes the proliferation and cell cycle progression of second heart field (SHF), an essential cell population that contribute to the developing OFT. In this study, we investigated the role of Osr1 in OFT development on cellular and molecular levels using a systems biology approach. We observed OFT rotation and elongation defects, as well as double-outlet right ventricle and overriding aorta as a result of SHF-specific deletion of Osr1. Using genetic inducible fate mapping, we showed that Osr1-expressing SHF …

Divergent Transcriptional Regulation Of Suppressors Of Cytokine Signaling Genes In Adipocytes, Paula Mota De Sa

LSU Doctoral Dissertations

The Janus Kinase - Signal Transducer and Activator of Transcription (JAK-STAT) signaling pathway transduces several signals crucial for development and homeostasis. Suppressors of cytokine signaling (SOCS) proteins control JAK-STAT signaling via a negative feedback loop. The transcription factor STAT5 is known to play a significant role in fat cell development and function, and several studies suggest that acetylation may affect STAT5 transcriptional activity. To test this hypothesis, we treated 3T3-L1 adipocytes with growth hormone (GH) to activate STAT5 in the presence or absence of histone deacetylase (HDAC) inhibitors. STAT5 acetylation levels were low in adipocytes and mostly unchanged by the …

Advanced Proteomic And Epigenetic Characterization Of Ethanol-Induced Microglial Activation, Jennifer Guergues Guergues

USF Tampa Graduate Theses and Dissertations

Microglia, the resident immune cells of the brain, can exhibit a broad range of activation phenotypes and have been implicated in several diseases and disorders of the central nervous system. Here, we described a method optimized for sensitive and rapid quantitative proteomic analysis of microglia that involves suspension trapping (S-Trap) for efficient and reproducible protein extraction from a microglial cell count expected from an individual mouse brain (~300K) while also simultaneously providing the first comprehensive proteomic characterization of a novel adult-derived mouse microglial cell line. This enhanced method was used throughout all subsequent works and was especially necessary when we …

Investigating The Role Of The Chromosome 19 Microrna Cluster In Human Trophoblast Differentiation And Infantile Hemangioma, Ezinne Francess Mong

USF Tampa Graduate Theses and Dissertations

Trophoblast differentiation and invasion is essential for normal implantation and establishment of the maternal-fetal interface, which allows for proper nutrient exchange and support of the fetus. For this to occur, cytotrophoblasts must undergo an epithelial to mesenchymal transition and differentiate into migratory and invasive extravillous trophoblasts (EVTs) that invade the maternal decidua and myometrium. Trophoblast differentiation, migration and invasion is highly regulated by a complex network of signaling pathways, adhesion molecules and transcription factors and is important for the remodeling of maternal spiral arteries from low flow, high resistance to high flow, low resistance vessels to allow optimal perfusion of …

Role Of P300 Zz Domain In Chromatin Association And Histone Acetylation, Yongming Xue

Dissertations and Theses (Open Access)

Transcription is strictly regulated by numerous factors including transcription coactivators. The p300 protein and its close paralogue CREB-binding protein (CREBBP, aka CBP) are well-known transcriptional coactivators that have intrinsic lysine acetyltransferase activity. The functions of p300/CBP largely rely on their capabilities to bind to chromatin and to acetylate the histone substrates. However, the molecular mechanisms underlying the regulation of these processes are not fully understood.

Through combination of various biochemical, biophysical and molecular approaches, we show that the ZZ-type zinc finger (ZZ) domain of p300 functions as a histone reader that specifically binds the N-terminal tail of histone H3. Crystal …

Genetic And Epigenetic Investigations On Pulmonary Hypertension Syndrome In Meat Type- Chickens, Khaloud Alzahrani

Graduate Theses and Dissertations

This dissertation presents a collection of studies that investigate the genetic and epigenetic associations to ascites phenotype in broiler chickens. Ascites is a significant metabolic disease associated with fast-growing meat-type chickens (broilers) and is a terminal result of pulmonary hypertension syndrome PHS. It is a multi-factorial syndrome caused by interactions between genetic, physiological, environmental, and managemental factors. It was estimated that ascites accounts for losses of about US$1 billion annually worldwide and for over 25% of broilers mortality. Although traditional and molecular genetic methods in the selection and in performance improvements, has greatly reduced ascites frequency, yet it has not …

The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland

Dissertations and Theses (Open Access)

DNA methylation is an essential epigenetic modification in mammals, as it plays important regulatory roles in multiple biological processes, such as gene transcription, maintenance of chromosomal structure and genomic stability, genomic imprinting, retrotransposon silencing, and X-chromosome inactivation. Dysregulation of DNA methylation is associated with various human diseases. For example, cancer cells usually show global hypomethylation and regional hypermenthylation, which have been implicated in genomic instability and tumor suppressor silencing, respectively. Although great progress has been made in elucidating the biological functions of DNA methylation over the last several decades, how DNA methylation patterns and levels are regulated and dysregulated is …

Investigation Of Alcohol-Induced Changes In Hepatic Histone Modifications Using Mass Spectrometry Based Proteomics, Crystina Leah Kriss

USF Tampa Graduate Theses and Dissertations

Alcohol liver disease (ALD) is a major health concern throughout the world. Currently, in the United States, 17 million people suffer from alcoholism, of which 1.4 million people are receiving treatment [1, 2]. The link between ethanol metabolism, reactive oxygen species (ROS) and liver injury in ALD has been well characterized over the last couple decades [3-10]. Ethanol metabolism relies on the availability of the cofactor NAD+ for the oxidation of ethanol into acetate, consequently causing alterations in redox potential. Redox dysfunction within the mitochondria can affect multiple pathways important in maintaining cellular homeostasis. Chapter 1 provides an introduction to …

Characterizing The Requirement Of The Cmi/Trr Compass-Like Complex During Drosophila Development, Timothy Nickels

Master's Theses

The MLR family of COMPASS-like complexes are histone methyltransferase complexes that are associated with the activation of gene enhancers. In D. melanogaster, Cara mitad (Cmi, also known as Lpt) and Trithorax related (Trr) are central subunits of a complex orthologous to mammalian Lysine methyltransferase 2 C and D (KMT2C and KMT2D, also known as MLL3 and MLL2/4) that catalyze H3K4 monomethylation. Previous studies have demonstrated that mutations in these genes are associated with cancer and developmental disorders, but the mechanisms by which these alterations contribute to disease states are unknown. The Cmi-containing COMPASS-like complex and orthologous vertebrate complexes have been …

The Dlk1-Meg3 Locus In Malignant Cells Of Proposed Primordial Germ Cell Origins., Zachariah Payne Sellers

Electronic Theses and Dissertations

Primordial germ cells (PGCs) are hypothesized to deposit hematopoietic stem cells (HSCs) along their migration route through the embryo during the early stages of embryogenesis. PGCs also undergo global chromatin remodeling, including the erasure and reestablishment of genomic imprints, during this migration. While PGCs do not spontaneously form teratomas, their malignant development into germ cell tumors (GCTs) in vivo is often accompanied by the retention of hypomethylation at the IGF2-H19 imprinting control differentially methylated region (DMR). Previous studies in bimaternal embryos determined that proper genomic imprinting at two paternally imprinted loci was necessary for their growth and development: Igf2-H19 and …

Epigenetic Editing To Validate Findings From Methylome-Wide Association Studies Of Neuropsychiatric Disorders, Robin F. Chan

Theses and Dissertations

DNA methylation is necessary for learning, memory consolidation and has been implicated in a number of neuropsychiatric disorders. Obtaining high quality and comprehensive data for the three common forms of methylation in brain is challenging for methylome-wide association studies (MWAS). To address this we optimized a panel of enrichment methods for screening the brain methylome. Results show that these enrichment techniques approach the coverage and fidelity of the current gold standard bisulfite based techniques. Our MBD-based method can also be used with low amounts of genomic material from limited human biomaterials. Psychiatric disorders have high prevalence and are often chronic …

New Open Conformation Of Smyd3 Implicates Conformational Selection And Allostery, Nicholas Spellmon, Xiaonan Sun, Wen Xue, Joshua Holcomb, Srinivas Chakravarthy, Weifeng Shang, Brian Fp Edwards, Nualpun Sirinupong, Chunying Li, Zhe Yang

Biochemistry and Molecular Biology Faculty Publications

SMYD3 plays a key role in cancer cell viability, adhesion, migration and invasion. SMYD3 promotes formation of inducible regulatory T cells and is involved in reducing autoimmunity. However, the nearly “closed” substrate-binding site and poor in vitro H3K4 methyltransferase activity have obscured further understanding of this oncogenically related protein. Here we reveal that SMYD3 can adopt an “open” conformation using molecular dynamics simulation and small-angle X-ray scattering. This ligand-binding-capable open state is related to the crystal structure-like closed state by a striking clamshell-like inter-lobe dynamics. The two states are characterized by many distinct structural and dynamical differences and the conformational …

Epigenetic Characterization Of Human Retina Cells, Nicholas R. Dunham

Senior Honors Projects, 2010-2019

DNA methylation is an epigenetic modifier that modulates gene expression in plant and vertebrate genomes. The aim of this study was to characterize the role of DNA methylation in the human retina, particularly within rod and cone photoreceptor retinal neurons. Previous studies investigating DNA methylation in murine retinal cells and retina-derived human retinoblastoma immortalized cell culture lines demonstrate an inverse relationship between DNA methylation and transcriptional activity. Here, we used gene-specific bisulfite pyrosequencing analysis to measure DNA methylation in the genomes of human ocular cells in an effort to characterize the role of this important epigenetic modifier. These results can …

Epigenetic Regulation Of Gene Expression During Spermatogenesis, Karishma Nayak

Senior Honors Projects

In the US livestock production industry, improving reproductive efficiency will improve animal welfare and maintain reasonable costs of meat and milk for consumers. In recent research, abnormalities in epigenetic markers in sperm during spermatogenesis, has been linked to male subfertility in many species. Epigenetics is the study of changes in organisms caused by modifications of gene expression, including DNA methylation, rather than alteration of the genetic code itself. When this process is disturbed, it can negatively impact semen therefore decreasing its fertility. Through further research on how DNA methylation influences gene expression during spermatogenesis and its impact on sperm quality, …