Genetics Commons^™

A Phylogenetic Analysis Of Dictyostelium Purpureum Based On Nuclear Rdna Sequences, Mahmoud Suliman

Graduate Theses and Dissertations

Dictyostelids (cellular slime molds) are eukaryotic microorganisms that have both unicellular and multicellular stages during their life cycle. In this study, a molecular phylogenetic analysis was conducted for isolates of one species (Dictyostelium purpureum) based DNA sequences of the ITS, 5.8S and SSU regions of nuclear rDNA. Moreover, a detailed morphological study was carried out using images obtained with both dissecting and compound microscopes. Mating experiments were carried out to assess macrocysts formation between each pair of isolates. The constructed molecular phylogenetic trees indicate that (1) D. purpureum isolates are more closely related to each other than to other species …

Investigation Of Genetic Alterations In Emt Suppressor, Dear1, Through Pan-Cancer Analysis And Ultra-Deep Targeted Sequencing In Ductal Carcinoma In Situ, Jacquelyn Reuther

Dissertations and Theses (Open Access)

Ductal carcinoma in situ (DCIS) is thought to be one of the earliest pre-invasive form of and non-obligate precursor to invasive ductal carcinoma (IDC). There is an urgent need to identify predictive and prognostic biomarkers for breast cancers with a heightened risk of progression from DCIS to IDC. Our laboratory has previously discovered a novel TRIM family member, DEAR1 (Ductal Epithelium Associated Ring Chromosome 1, annotated as TRIM62) within chromosome 1p35.1, that is mutated and homozygously deleted in breast cancer and whose expression is downregulated/lost in DCIS. Previous work has shown that DEAR1 is a novel tumor suppressor …

Genetics Of Obesity In Starr County, Texas Mexican Americans, Heather M. Highland

Dissertations and Theses (Open Access)

Currently, over two-thirds of Americans are classified as over-weight or obese. Obesity increases risk for many other diseases including type 2 diabetes, heart disease, stroke, and cancer, making obesity the largest public health problem in America and most other Westernized nations. Hispanics have a higher rate of both obesity and type 2 diabetes, making them a particularly interesting population in which to study obesity. For the last 33 years, the Starr County Health Studies has collected an array of phenotypes and biological samples from residents of Starr County, along Texas-Mexico border. This study includes 825 subjects who were not known …

Elucidating The Role Of Rumi And O-Glucosylation In The Drosophila Eye, Amanda Haltom

Dissertations and Theses (Open Access)

Rumi is a protein O-glucosyltransferase that adds the sugar O-glucose onto the serine in the target sequence C-S-X-S-(P/A)-C found within properly folded EGF repeats. It was first discovered to modify the Drosophila Notch extracellular domain and to be required for Notch signaling in a temperature dependent manner, but other targets of Rumi remained unknown. Several other proteins in the Drosophila proteome harbor multiple consensus sequence highly predictive of O-glucose, including the transmembrane protein Crumbs and the secreted protein Eyes shut (Eys). Both of these proteins are required for proper eye development and mutations in their human homologs …

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

Dissertations and 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 …

Spiritual Exploration In The Prenatal Genetic Counseling Session, Katelynn G. Sagaser

Dissertations and Theses (Open Access)

Religion and spirituality are important components of many individuals’ lives, and spiritual needs may present among persons receiving medical care. Spirituality has been demonstrated to be significant in the coping of women experiencing pregnancy complications (Breen et al. 2006; Price et al. 2007). To characterize the manner in which prenatal genetic counselors might address spiritual issues with their patients, we surveyed 283 patients receiving prenatal genetic counseling using the Brief RCope and a series of questions that examined interest in spiritual exploration. Counselors were concurrently surveyed to identify the spiritual language used within the session and the counselor’s perceived importance …

Evaluating The Nccn Clinical Criteria For Hereditary Breast And Ovarian Cancer Syndrome Genetic Testing, Caiqian Wu

Dissertations and Theses (Open Access)

Hereditary Breast and Ovarian Cancer (HBOC) syndrome predisposes females with a BRCA1 or BRCA2 mutation to an up to 85% lifetime risk for breast cancer and an up to 40% lifetime risk for ovarian cancer. It is crucial for individuals with HBOC to be identified to allow for proper screening, management, and identification of at-risk family members in order to reduce mortality. The National Comprehensive Cancer Network (NCCN) has established clinical guidelines for when to recommend BRCA1/2 testing. A retrospective chart review of 1123 M.D. Anderson Cancer Center breast cancer patients was performed in order to evaluate the positive predictive …

Impact Of Differentiation Status Of Kidney Progenitors In Wilms Tumor Development, Le Huang

Dissertations and Theses (Open Access)

Wilms tumor is one of the most common solid tumors in children. It is an embryonic cancer of the kidney and is thought to arise from undifferentiated renal mesenchyme. However, the differentiation status of cells in the mesenchyme that can give rise to Wilms tumors is unknown. Gene expression analysis of a large panel of Wilms tumor patients has identified different subsets of Wilms tumors that are distinct in their clinical outcomes and gene expression signatures. These subsets express specific genes that correspond to different stages of differentiation during renal development, suggesting that Wilms tumors may arise from transformed cells …

Deciphering The Functional Collaboration Of Mid And Bric-A-Brac 2 As Potential Regulators Of Cellular Proliferation Within Adult Drosophila Ovaries, Petra Visic

Master's Theses

Stem cell niches are highly organized and specialized microenvironments located within specific tissues of both vertebrate and invertebrate organisms [1]. In Drosophila melanogaster, three distinct stem cell niches have been identified within the ovary including the germline stem cell (GSC), follicle stem cell (FSC), and escort stem cell (ESC) niche. Recently, Fregoso-Lomas et al. [2] reported that Gurken/Epidermal Growth Factor Receptor (EGFR) signaling is modulated within posterior ovarian follicle cells by Midline (Mid). The mid gene encodes a T-box transcription factor protein that specifies cell fates in the developing heart [3][4], central nervous system [5][6], epidermis [7], and eye …

Divergent Selection For Four-Day Relative Breast Yield And The Effect Of Thermal Manipulations On Growth Characteristics On Lines Selected For Different Processing Dates., James Grant Mason

Graduate Theses and Dissertations

Genetic selections currently utilized in the poultry industry have been highly successful in promoting broiler growth rate and yield. However, these selections may have come at the expense of broiler physiology, as evidenced by an increase in physiological disorders. To address this experimentation was undergone to develop a novel method of selection to promote growth with minimal physiological impact and to assess how a new embryonic technique affects growth in broiler lines exhibiting different growth rates.

In the first experiment, a random bred control (RAN) broiler line was divergently selected for four-day relative breast yield (BY4) resulting in the high …

Heterogeneous Dynamics In Dna Site Discrimination By The Structurally Homologous Dna-Binding Domains Of Ets-Family Transcription Factors, Gaofei He, Ana Tolic, James Bashkin, Gregory Poon

Chemistry & Biochemistry Faculty Works

The ETS family of transcription factors exemplifies current uncertainty in how eukaryotic genetic regulators with overlapping DNA sequence preferences achieve target site specificity. PU.1 and Ets-1 represent archetypes for studying site discrimination by ETS proteins because their DNA-binding domains are the most divergent in sequence, yet they share remarkably superimposable DNA-bound structures. To gain insight into the contrasting thermodynamics and kinetics of DNA recognition by these two proteins, we investigated the structure and dynamics of site discrimination by their DNA-binding domains. Electrophoretic mobilities of complexes formed by the two homologs with circularly permuted binding sites showed significant dynamic differences only …

Repsa-Directed Identification Of Dna-Binding Specificity For Orphan Transcription Factors, Kamir Hiam

Symposium of Student Scholars

The function of many genes and the biological roles of their encoded products are still not well characterized. Given the sequence-specific DNA-binding properties of transcription factor proteins, it is possible to purify them, identify the responsible polypeptide(s), determine their consensus binding sequences, and identify their genomic binding sites. Thus, one can go from cellular extract to proposed biological regulatory roles in relatively short order. Our goal is to identify and characterize orphan DNA-binding proteins in the model organism E. coli K12 using the novel combinatorial technique, REPSA (Restriction Endonuclease Protection Selection Amplification), as well as further develop the REPSA to …

Relative Abundances Of The Recently Introduced Barnacles, Megabalanus Coccopoma And An Unidentified Species Of Megabalanus, In The Southeastern U.S., Jennifer L. Tyson

Honors College Theses

ABSTRACT

Megabalanus coccopoma is a prominent invasive species off the coast of Georgia. Recently, among collected samples thought to be M. coccopoma, several individuals of an unidentified species of barnacle were found. The species has been identified as a Megabalanus species, but is still unidentified to the species level. Species identification is difficult due to morphological variation, inconsistent taxonomic keys, and unknown origin. In this study I developed a method to accurately distinguish M. coccopoma from the unidentified Megabalanus sp. using sequence differences in the mitochondrial Cytochrome Oxidase I (COI) gene. This study will provide an accurate estimate of …

Phenotypic Heterogeneity In Metabolic Traits Among Single Cells Of A Rare Bacterial Species In Its Natural Environment Quantified With A Combination Of Flow Cell Sorting And Nanosims, Matthias Zimmermann, Matthias Zimmermann, Stéphanie Escrig, Thomas Hübschmann, Mathias Kirf, Mathias Kirf, Andreas Brand, Andreas Brand, R. Inglis, R. Inglis, Niculina Musat, Susann Müller, Andres Meibom, Andres Meibom, Martin Ackermann, Martin Ackermann, Frank Schreiber, Frank Schreiber

Biology Department Faculty Works

Populations of genetically identical microorganisms residing in the same environment can display marked variability in their phenotypic traits; this phenomenon is termed phenotypic heterogeneity. The relevance of such heterogeneity in natural habitats is unknown, because phenotypic characterization of a sufficient number of single cells of the same species in complex microbial communities is technically difficult. We report a procedure that allows to measure phenotypic heterogeneity in bacterial populations from natural environments, and use it to analyze N2 and CO2 fixation of single cells of the green sulfur bacterium Chlorobium phaeobacteroides from the meromictic lake Lago di Cadagno. We incubated lake …

Species Interactions Differ In Their Genetic Robustness, Lon Chubiz, Brian Granger, Daniel Segrè, William Harcombe

Biology Department Faculty Works

Conflict and cooperation between bacterial species drive the composition and function of microbial communities. Stability of these emergent properties will be influenced by the degree to which species’ interactions are robust to genetic perturbations. We use genome-scale metabolic modeling to computationally analyze the impact of genetic changes when Escherichia coli and Salmonella enterica compete, or cooperate. We systematically knocked out in silico each reaction in the metabolic network of E. coli to construct all 2583 mutant stoichiometric models. Then, using a recently developed multi-scale computational framework, we simulated the growth of each mutant E. coli in the presence of S. …

Investigating The Initial Detection Stage Of Meiotic Silencing By Unpaired Dna In The Model Organism Neurospora Crassa, Pegan A. Sauls

Theses and Dissertations

In an attempt to neutralize transposable elements or retrovirus invasions Neurospora crassa will rely on one of its many genome defense mechanism, Meiotic Silencing by Unpaired DNA (MSUD). MSUD works in a two-step process that first detects unpaired sequences between homologous chromosomes followed by downstream silenced expression of the sequence. The ultimate silencing stage of MSUD is widely accepted to operate through an RNAi-like system. However, the mechanics of the detection step of MSUD remains elusive. The research presented attempts to elaborate on how the initial stage of MSUD occurs and its specifics. First, a genetic approach is utilized to …

Parallel And Divergent Evolutionary Solutions For The Optimization Of An Engineered Central Metabolism In Methylobacterium Extorquens Am1, Sean Carroll, Lon Chubiz, Deepa Agashe, Christopher Marx

Biology Department Faculty Works

Bioengineering holds great promise to provide fast and efficient biocatalysts for methanol-based biotechnology, but necessitates proven methods to optimize physiology in engineered strains. Here, we highlight experimental evolution as an effective means for optimizing an engineered Methylobacterium extorquens AM1. Replacement of the native formaldehyde oxidation pathway with a functional analog substantially decreased growth in an engineered Methylobacterium, but growth rapidly recovered after six hundred generations of evolution on methanol. We used whole-genome sequencing to identify the basis of adaptation in eight replicate evolved strains, and examined genomic changes in light of other growth and physiological data. We observed great variety …

Fisheries Management Paper No.273 - Blue Swimmer Crab Resource Of The Peel-Harvey Estuary Harvest Strategy, 2015-2020. Version 1.0, Department Of Fisheries, Western Australia

Fisheries Management Papers

Harvest strategies for aquatic resources managed by the Western Australian Department of Fisheries (the Department) are formal documents prepared to support the decision-making processes required to ensure the management of these resources are consistent with the principles of Ecologically Sustainable Development (ESD). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA), Section 3, and the draft Aquatic Resources Management Bill 2013 (ARMB), Clause 9, which will replace the FRMA once enacted.

The publication of these strategies is intended to make the decision-making considerations and processes for the management of specified aquatic resources …

Genetic, Agronomic And Compositional Characterization Of Brown Midrib Sweet Sorghum Lignocellulosic Biomass For Ethanol Production, Luis A. Rivera Burgos

Open Access Dissertations

Sorghum is a promising bioenergy crop due to its unique phenotypic and genotypic attributes. Quality (low lignin and high stem sugar concentration) and quantity (biomass yield, plant height, plant maturity, etc.) biomass traits are key contributors to ethanol yield and production. In this study, a 236 sorghum recombinant inbred line (RIL) population was subjected to genetic, agronomic and compositional characterization for ethanol yield and production. We found that the sweet mutation enhances biomass quantity traits in the RILs which translates to higher ethanol production and biomass quality which improves ethanol yield. The variance components showed from moderate to high heritability …

The Evolutionary Origination And Diversification Of A Dimorphic Gene Regulatory Network Through Parallel Innovations In Cis And Trans, Eric M. Camino, John C. Butts, Alison J. Ordway, Jordan E. Vellky, Mark Rebeiz, Thomas M. Williams

Biology Faculty Publications

The origination and diversification of morphological characteristics represents a key problem in understanding the evolution of development. Morphological traits result from gene regulatory networks (GRNs) that form a web of transcription factors, which regulate multiple cis-regulatory element (CRE) sequences to control the coordinated expression of differentiation genes. The formation and modification of GRNs must ultimately be understood at the level of individual regulatory linkages (i.e., transcription factor binding sites within CREs) that constitute the network. Here, we investigate how elements within a network originated and diversified to generate a broad range of abdominal pigmentation phenotypes among Sophophora fruit flies. …