Life Sciences Commons^™

Chimerscope: A Novel Alignment-Free Algorithm For Fusion Gene Prediction Using Paired-End Short Reads, You Li

Theses & Dissertations

Fusion genes are those that result from the fusion of two or more genes, and they are typically generated due to the perturbations in the genome structure in cancer cells. In turn, fusion genes can contribute to tumor formation and progression by promoting the expression of an oncogene, deregulation of a tumor-suppressor, or producing much more active abnormal proteins. More importantly, oncogenic fusion genes are specifically expressed in the tumor cells, which provide enormous diagnostic and therapeutic advantages for cancer treatment. With the development of next-generation sequencing (NGS) technology, RNA-Seq becomes increasingly popular for transcriptomic study because of its high …

Investigations On The Vampire Moth Genus Calyptra Ochsenheimer, Incorporating Taxonomy, Life History, And Bioinformatics (Lepidoptera: Erebidae: Calpinae), Julia L. Snyder

Open Access Theses

The seventeen species and two subspecies described in the genus Calyptra are known to be obligate fruit piercers, with some species being of economic importance. Males within the genus have not only been observed piercing their fruit hosts, but have also been documented to occasionally feed on mammalian blood. The genetic and ecological mechanisms contributing to host preference for either plant or vertebrate hosts in this lineage are unknown. Thus, the focus of this study was to investigate the chemosensory systems between and among Calyptra species exhibiting differential feeding strategies. Before investigating the chemosensory systems within Calyptra, the taxonomy …

Dynamic Regulation Of Dna Demethylation And Rna-Directed Dna Methylation In Arabidopsis, Kai Tang

Open Access Dissertations

DNA methylation is an important epigenetic mark present in many eukaryotes, and is involved in many crucial biological processes, such as gene imprinting, regulation of gene expression, and genome stability. Proper genomic DNA methylation patterns are achieved through the concerted action of DNA methylation and demethylation pathways. In the model plant species Arabidopsis thaliana, ROS1 (REPRESSOR OF SILENCING 1) is one of the DNA demethylases and the key component in the demethylation pathway. Dysfunction of ROS1 leads to increase in DNA methylation level at thousands of genomic loci. However, the features of ROS1 targets are not well understood. In the …

Whole Genome Sequencing As A Tool For Identifying Phenotypic Properties And Underlying Genetic Mechanisms In Staphylococcus Pseudintermedius, Matthew C. Riley

Doctoral Dissertations

Staphylococcus pseudintermedius is a Gram-positive bacterial opportunistic pathogen commonly associated with dermal infections in canines, but capable of causing serious disease in other species. Reports of human infections caused by S. pseudintermedius along with an increase in resistance to multiple antibiotics highlights the importance of this organism. Whole genome sequencing can allow large scale investigation of genetic mechanisms underlying phenotypic properties that contribute to the expansion of successful S. pseudintermedius clonal lineages.

The increase in multidrug and methicillin-resistant S. pseudintermedius (MRSP) may result from horizontal transfer of genetic material between bacterial isolates, yet is thought to be rare in Staphylococci …

Punctuated Evolution Within A Eurythermic Genus (Mesenchytraeus) Of Segmented Worms: Genetic Modification Of The Glacier Ice Worm F1f0 Atp Synthase, Shirley A. Lang

Graduate School of Biomedical Sciences Theses and Dissertations

Segmented worms (Annelida) are among the most successful animal inhabitants of extreme environments worldwide. An unusual group of Mesenchytraeus worms endemic to the Pacific Northwest of North America occupy geographically proximal ecozones ranging from low elevation temperate rainforests to high altitude glaciers. Along this altitudinal transect, Mesenchytraeus representatives from disparate habitat types were collected and subjected to deep mitochondrial and nuclear phylogenetic analyses. Evidence presented here employing modern bioinformatic analyses (i.e., maximum likelihood, Bayesian inference, multi-species coalescent) supports a Mesenchytraeus “explosion” in the upper Miocene (5-10 million years ago) that gave rise to ice, snow and terrestrial worms, derived from …

Computational Analyses Of Mrna Ribosome Loading In Arabidopsis Thaliana, Joseph Benjamin Ernest

Doctoral Dissertations

Translation of mRNA into protein is a critical step in gene expression, but the principles guiding its regulation at the genome level are not completely understood. Translation can be quantified at a genome scale by measuring the ribosome loading of mRNA—the extent to which mRNA is associated with ribosomes. In this dissertation, I present investigations into how genome-wide ribosome loading is controlled in Arabidopsis thaliana. In chapter 1, I give an overview of regulation of ribosome loading and translation. In chapter 2, I present research demonstrating for the first time that genome-wide ribosome loading in plants is partially controlled by …

Stream Microbial Communities As Potential Indicators Of River And Landscape Disturbance In North-Central Arkansas, Wilson Howard Johnson

Graduate Theses and Dissertations

In the past decade, 29 shale basins have been actively developed across 20 states for extraction of natural gas (NG) via horizontal drilling/hydraulic fracturing (=fracking). This includes ~5000 wells within the Fayetteville shale of north-central Arkansas. Development often impacts both river- and landscapes, and management requires catchment-level evaluations over time, with organismal presence/absence as indicators. For this study next-generation sequencing was used to identify/characterize microbial communities within biofilm of eight Arkansas River tributaries, so as to gauge potential catchment influences. Streams spanned a gradient of landscape features and hydrological flows, with four serving as ‘potentially impacted catchment zones’ (PICZ) and …

Development Of An In Silico Kir Genotyping Algorithm And Its Application To Population And Cancer Immunogenetic Analyses, Howard Rosoff

Dissertations & Theses (Open Access)

Gene content determination and variant calling in the complex KIR genomic region are useful for immune system function analysis, pathogenesis and disease risk factor elucidation, immunotherapy development, evolutionary investigations, and human migration modeling. Sequence-specific oligonucleotide and sequence-specific primer PCR methods are the de facto standards for KIR presence/absence identification, but the current platforms are unsuitable for SNP calling, impractical for KIR typing large cohorts of DNA samples, and inapplicable for typing repositories in which sequence data, but not cells or cell analytes, are available. Alternative typing methods, such as in silico sequence-based typing, can address the problems associated with amplicon-based …

Diversity And Distribution Of Diatom Endosymbionts In Amphistegina Spp. (Foraminifera) Based On Molecular And Morphological Techniques, Kwasi H. Barnes

USF Tampa Graduate Theses and Dissertations

Diatoms associated with foraminifers of the genus Amphistegina were assessed using a combination of morphological and molecular techniques. These included: 1) microscopic identification of diatoms cultured from the host, 2) sequencing of portions of the small subunit of the ribosomal RNA gene (18S) and the large subunit of the ribulose-1,5-bisphosphate carboxylase/oxygenase [i.e., RubisCO] gene (rbcL) from DNA extracted directly from the Amphistegina hosts and also from diatoms cultured from these hosts, and 3) denaturing gradient gel electrophoresis (DGGE) profiles of rbcL and internal transcribed spacer 1 (ITS1) PCR amplicons from DNA extracted directly from …

Measuring The Human Gut Microbiome: New Tools And Non Alcoholic Fatty Liver Disease, Ruth G. Wong

Electronic Thesis and Dissertation Repository

With the advent of next generation DNA and RNA sequencing, scientists can obtain a more comprehensive snapshot of the bacterial communities on the human body (known as the `human microbiome'), leading to information about the bacterial composition, what genes are present, and what proteins are produced. The scientific community is in a phase of developing the experiments and accompanying statistical techniques to investigate the mechanisms by which the human microbiome affects health and disease. In this thesis, I explore alternatives to the standard weighted and unweighted UniFrac distance metric that measure the difference between microbiome samples. These alternative weightings allow …

Development And Application Of Comparative Gene Co-Expression Network Methods In Brachypodium Distachyon, Henry David Priest

Arts & Sciences Electronic Theses and Dissertations

Gene discovery and characterization is a long and labor-intensive process. Gene co-expression network analysis is a long-standing powerful approach that can strongly enrich signals within gene expression datasets to predict genes critical for many cellular functions. Leveraging this approach with a large number of transcriptome datasets does not yield a concomitant increase in network granularity. Independently generated datasets that describe gene expression in various tissues, developmental stages, times of day, and environments can carry conflicting co-expression signals. The gene expression responses of the model C3 grass Brachypodium distachyon to abiotic stress is characterized by a co-expression-based analysis, identifying 22 modules …

Restriction Enzyme Generated Next-Generation Sequencing Libraries And Genetic Risk Modifiers Of Brca1 Mutation Carriers, Bradley Downs

Theses & Dissertations

Next-generation sequencing (NGS) is a high throughput technique used to sequence large amounts of DNA in a short amount of time. However, a limitation to NGS is that the generated data is in a single consensus sequence without distinguishing between variants on homologous chromosomes. Separating or phasing the variants from the maternal and paternal chromosomes can provide information about the genetic origin of disease and information about how DNA nucleotide alterations interact in cis. This dissertation explores a new technical method of using restriction enzymes during NGS library preparation and its ability to increase the amount of phasing information that …

Assessment Of Next Generation Sequencing Technologies For De Novo And Hybrid Assemblies Of Challenging Bacterial Genomes, Sagar Mukund Utturkar

Doctoral Dissertations

In past decade, tremendous progress has been made in DNA sequencing methodologies in terms of throughput, speed, read-lengths, along with a sharp decrease in per base cost. These technologies, commonly referred to as next-generation sequencing (NGS) are complimented by the development of hybrid assembly approaches which can utilize multiple NGS platforms. In the first part of my dissertation I performed systematic evaluations and optimizations of nine de novo and hybrid assembly protocols across four novel microbial genomes. While each had strengths and weaknesses, via optimization using multiple strategies I obtained dramatic improvements in overall assembly size and quality. To select …

Computational Identification Of Terpene Synthase Genes And Their Evolutionary Analysis, Qidong Jia

Doctoral Dissertations

Terpenoids, the largest and most structurally and functionally diverse class of natural compounds on earth, are mostly synthesized by plants to be involved in various plant environment interactions. Some terpenoids are classified as primary metabolites essential for plant growth and development. Terpene synthases (TPSs), the key enzymes for terpenoid biosynthesis, are the major determinant of the tremendous diversity of terpenoid carbon skeletons. The TPS genes represent a mid-size family of about 30-100 functional genes in almost all major sequenced plant genomes. TPSs are also found in fungi and bacteria, but microbial TPS genes share low levels of sequence similarity and …

The Application Of The Hadoop Software Framework In Bioinformatics Programs, Dan Wang

Open Access Dissertations

The project described in this dissertation proposal attempted to improve the efficiency and scalability performance as well as the usability and user experience of three Bioinformatics applications - DNA/peptide sequence similarity comparison, digital DNA library subtraction, and DNA/peptide sequence de-duplication - by 1) adopting the Hadoop MapReduce algorithms and distributed file system and 2) implementing the fully automated Hadoop programs into a user friendly graphical user interface (GUI). In addition, the researcher was also interested in investigating the advantages and limitations of applying the Hadoop software framework as a general methodology in parallelizing Bioinformatics programs.

After considering the original calculation …

Evaluating The Performance Of In Silico Predictive Models On Detecting Splice-Altering Variants, Erica Cayton

Dissertations, Masters Theses, Capstones, and Culminating Projects

As with any complex biological pathway, the splicing process has both advantages and obstacles with respect to the diversity and fidelity of protein production. The potential benefits of being able to produce multiple versions of a gene (isoforms) must be weighed against the additional complexity introduced by the noisy and mechanistically complicated process of splicing. Indeed, research has found that errors in splicing can be implicated in an increasing number of disorders. Variants that cause disease may operate by disrupting splicing; however many of the variants are frequently annotated as disrupting function through a missense mutation, or via an unknown …

A Bioinformatics Approach To Addressing The Responses Of Rice Aleurone Cells To Hormones Abscisic Acid And Gibberellic Acid, Kenneth Arthur Watanabe

UNLV Theses, Dissertations, Professional Papers, and Capstones

The hormone abscisic acid (ABA) is biosynthesized by higher plants in response to various abiotic stresses such as drought and antagonizes the growth and germination-promoting hormone gibberellic acid (GA). The seed is a model system for studying desiccation tolerance and germination. The thin layer of cells surrounding the seed, the aleurone layer, plays a direct role in seed germination and an indirect role in desiccation tolerance. The goal of my research is to address the molecular mechanism underlying the responses of rice aleurone cells to ABA and GA, by taking a genomics approach. An accurate and complete annotation of the …

Expression Of Zinc Fingers And Homeoboxes 2 (Zhx2) And Zhx2 Target Genes In Multiple Tissues Of Wild-Type And Zhx2 Knockout Mice, Minen Al-Kafajy

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

The Spear lab has had a long-standing interest in gene regulation in the liver during development and disease. Several years ago, these studies identified a novel transcriptional regulator called Zinc fingers and homeoboxes 2 (Zhx2), which is a member of a small family that includes Zhx1 and Zhx3. All Zhx proteins contain two amino-terminal C2-H2 zinc fingers and four or five carboxy-terminal homeodomains. Previous studies indicate that Zhx proteins can form homodimers and heterodimers with each other.

Zhx2 regulates numerous hepatic genes, including alpha-fetoprotein (AFP) and H19. Genes controlling lipid and cholesterol homeostasis are also regulated by …

A Pipeline For Creation Of Genome-Scale Metabolic Reconstructions, Shaun W. Norris

Theses and Dissertations

The decreasing costs of next generation sequencing technologies and the increasing speeds at which they work have lead to an abundance of 'omic datasets. The need for tools and methods to analyze, annotate, and model these datasets to better understand biological systems is growing. Here we present a novel software pipeline to reconstruct the metabolic model of an organism in silico starting from its genome sequence and a novel compilation of biological databases to better serve the generation of metabolic models. We validate these methods using five Gardnerella vaginalis strains and compare the gene annotation results to NCBI and the …