Open Access. Powered by Scholars. Published by Universities.®

Genetics and Genomics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Genetics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1951 - 1980 of 3170

Full-Text Articles in Genetics and Genomics

Population Structure Of Central Stoneroller (Campostoma Anomalum) On The Ozark Plateau In Arkansas And Missouri, Mallory Jane Jeffers Jul 2015

Population Structure Of Central Stoneroller (Campostoma Anomalum) On The Ozark Plateau In Arkansas And Missouri, Mallory Jane Jeffers

Graduate Theses and Dissertations

Stream fishes on the Ozark Plateau have been influenced both by historic events (i.e. vicariance versus dispersal) and ecological forces (i.e. flow regime). To examine the role of these processes, genetic structure of Central Stoneroller (Campostoma anomalum), an ecologically important omnivorous minnow with a broad distribution and elevated abundance, was evaluated across populations in the White River drainage of the Ozark Plateau in Arkansas and Missouri. Fin clips of five to eight individuals were taken at each of 20 sites (N=138 individuals; average=6.9), selected so as to represent two different flow regimes: intermittently flashy (N=10 sites; N=73 individuals; average=7.3/ site) …


Role Of Metabolic Shifts In Protection From Mutation Damage: Characterizing Mitochondrial Membrane Potential In C. Elegans Gas-1 Mutants, Lauren S. Muñoz-Tremblay Jun 2015

Role Of Metabolic Shifts In Protection From Mutation Damage: Characterizing Mitochondrial Membrane Potential In C. Elegans Gas-1 Mutants, Lauren S. Muñoz-Tremblay

PSU McNair Scholars Online Journal

Many terminal human diseases are caused by mutations affecting mitochondrial functioning. Mitochondria are essential organelles responsible for producing cellular energy, adenosine triphosphate (ATP) via oxidative phosphorylation (OXPHOS) at mitochondrial electron transport chains (ETC). Proper ETC functioning relies on maintenance of the electrochemical gradient essential for energy production, known as mitochondrial membrane potential (ΔψM). The inner mitochondrial membrane is the site of the ETC and is most closely in contact with the enzymatic processes occurring within the mitochondrial matrix. Mutations affecting protein components of the ETC are especially troublesome for organelle health. ETC mutants commonly express altered ΔψM, as well as …


Cell Wall Mutants In Arabidopsis Thaliana, Christy Jane Moore Jun 2015

Cell Wall Mutants In Arabidopsis Thaliana, Christy Jane Moore

Theses and Dissertations

Plant cell walls are versatile structures, playing important roles in communication, defense, organization and support. The importance of each of these functions varies by cell type, with specialized cells often utilizing one or two functions more than others. Trichomes, or leaf hairs, and hypocotyl cells for instance, exhibit distinct cell wall characteristics. Trichomes have developed very thick cell walls with several raised structures, known as papillae, on their surfaces. It is believed that these cells function in defense against predators, making it difficult to crawl on the leaf surface, and in protection against ultra violet radiation, through refraction of light …


Mutations That Separate The Functions Of The Proofreading Subunit Of The Escherichia Coli Replicase, Zakiya Whatley, Kenneth N. Kreuzer Jun 2015

Mutations That Separate The Functions Of The Proofreading Subunit Of The Escherichia Coli Replicase, Zakiya Whatley, Kenneth N. Kreuzer

Biology Faculty Publications

The dnaQ gene of Escherichia coli encodes the Ɛ subunit of DNA polymerase III, which provides the 3' - 5' exonuclease proofreading activity of the replicative polymerase. Prior studies have shown that loss of Ɛ leads to high mutation frequency, partially constitutive SOS, and poor growth. In addition, a previous study from our laboratory identified dnaQ knockout mutants in a screen for mutants specifically defective in the SOS response after quinolone (nalidixic acid) treatment. To explain these results, we propose a model whereby, in addition to proofreading, Ɛ plays a distinct role in replisome disassembly and/or processing of stalled replication …


Mongolians In The Genetic Landscape Of Central Asia: Exploring The Genetic Relations Among Mongolians And Other World Populations, Jane E. Brissenden, Judith R. Kidd, Baigalmaa Evsanaa, Ariunaa Togtokh, Andrew J. Pakstis, Françoise Friedlaender, Kenneth K. Kidd, Janet M. Roscoe Jun 2015

Mongolians In The Genetic Landscape Of Central Asia: Exploring The Genetic Relations Among Mongolians And Other World Populations, Jane E. Brissenden, Judith R. Kidd, Baigalmaa Evsanaa, Ariunaa Togtokh, Andrew J. Pakstis, Françoise Friedlaender, Kenneth K. Kidd, Janet M. Roscoe

Human Biology Open Access Pre-Prints

Genetic data on North Central Asian populations are underrepresented in the literature, especially autosomal markers. In the present study we use 812 single nucleotide polymorphisms that are distributed across all the human autosomes and that have been extensively studied at Yale to examine the affinities of two recently collected, samples of populations: rural and cosmopolitan Mongolians from Ulaanbaatar and nomadic, Turkic-speaking Tsaatan from Mongolia near the Siberian border. We compare these two populations to one another and to a global set of populations and discuss their relationships to New World populations. Specifically, we analyze data on 521 autosomal loci (single …


Genetic Changes To A Transcriptional Silencer Element Confers Phenotypic Diversity Within And Between Drosophila Species, Winslow C. Johnson, Alison J. Ordway, Masayoshi Watada, Jonathan N. Pruitt, Thomas M. Williams, Mark Rebeiz Jun 2015

Genetic Changes To A Transcriptional Silencer Element Confers Phenotypic Diversity Within And Between Drosophila Species, Winslow C. Johnson, Alison J. Ordway, Masayoshi Watada, Jonathan N. Pruitt, Thomas M. Williams, Mark Rebeiz

Biology Faculty Publications

The modification of transcriptional regulation has become increasingly appreciated as a major contributor to morphological evolution. However, the role of negative-acting control elements (e.g. silencers) in generating morphological diversity has been generally overlooked relative to positive-acting “enhancer” elements. The highly variable body coloration patterns among Drosophilid insects represents a powerful model system in which the molecular alterations that underlie phenotypic diversity can be defined. In a survey of pigment phenotypes among geographically disparate Japanese populations of Drosophila auraria, we discovered a remarkable degree of variation in male-specific abdominal coloration. In testing the expression patterns of the major pigment-producing enzymes, …


Origins Of An Unmarked Georgia Cemetery Using Ancient Dna Analysis, Andrew T. Ozga, Raúl Y. Tito, Brian M. Kemp, Hugh Matternes, Alexandra Obregon-Tito, Leslie Neal, Cecil M. Lewis, Jr. Jun 2015

Origins Of An Unmarked Georgia Cemetery Using Ancient Dna Analysis, Andrew T. Ozga, Raúl Y. Tito, Brian M. Kemp, Hugh Matternes, Alexandra Obregon-Tito, Leslie Neal, Cecil M. Lewis, Jr.

Human Biology Open Access Pre-Prints

Determining the origins of those buried within undocumented cemeteries is of incredible importance to historical archaeologists and in many cases, the nearby communities. In the case of Avondale Burial Place, a cemetery in Bibb County, Georgia, in use from 1820 to 1950, all written documentation of those interred within it has been lost. Osteological and archaeological evidence alone could not describe, with confidence, the ancestral origins of the 101 individuals buried there. In the present study, we utilize ancient DNA extraction methods to investigate the origins of Avondale Burial Place through the use of well-preserved skeletal fragments from 20 individuals …


Divergence Of Vertebrate And Insect Specific Toxin Genes Between Three Species Of Widow Spider, Shannon G. Kahn May 2015

Divergence Of Vertebrate And Insect Specific Toxin Genes Between Three Species Of Widow Spider, Shannon G. Kahn

Honors College Theses

The Brown widow spider, Latrodectus geometricus, is an introduced species to the southern United States (Brown 2008). The Brown widow is a member of the widow spider genus Latrodectus which includes the southern Black widow (L. mactans) and 29 other venomous species. All species of widow spiders produce venom which is used against both predator and prey. These venoms are composed of several different species-specific toxins, each encoded by a different gene (Graudins 2012). Previous research has shown that positive selection pressures affect the venom of snakes and snails, thus aiding in adaptive potential of the species …


Fisheries Management Paper No 274 - Finfish Resources Of The Peel-Harvey Estuary - Harvest Strategy 2015-2020 (Version 1.0), Department Of Fisheries, Western Australia May 2015

Fisheries Management Paper No 274 - Finfish Resources Of The Peel-Harvey Estuary - Harvest Strategy 2015-2020 (Version 1.0), Department Of Fisheries, Western Australia

Fisheries Management Papers

WEST COAST ESTUARINE MANAGED FISHERY (AREA 2)

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 …


Characterization Of A Novel Clade Of Transporters In Phytophthora, Stephanie Padula, Paul F. Morris Dr, Howard Casey Cromwell Dr., Menaka Ariyaratne, Andrew Wagner May 2015

Characterization Of A Novel Clade Of Transporters In Phytophthora, Stephanie Padula, Paul F. Morris Dr, Howard Casey Cromwell Dr., Menaka Ariyaratne, Andrew Wagner

Honors Projects

The oomycete Phytophthora parasitica has a worldwide distribution and is an economically important pathogen of more than 100 species4. RNA-seq analysis showed that one gene, PPTG_16698 has the 5th highest level of expression of all transport proteins in the zoospore stage, and is highly conserved throughout Phytophthora species. This project attempts to characterize the important biological role that PPTG_16698 plays in P. parasitica and other oomycetes. Three strategies have been implemented to accomplish this goal: growth analysis by heterologous expression in yeast, metabolite analysis in yeast, and construction of a GFP fusion protein to enable localization of …


An Inquiry-Infused Introductory Biology Laboratory That Integrates Mendel's Pea Phenotypes With Molecular Mechanisms, Philip Kudish, E. Schlag, Nicholas J. Kaplinsky May 2015

An Inquiry-Infused Introductory Biology Laboratory That Integrates Mendel's Pea Phenotypes With Molecular Mechanisms, Philip Kudish, E. Schlag, Nicholas J. Kaplinsky

Biology Faculty Works

We developed a multi-week laboratory in which college-level introductory biology students investigate Mendel's stem length phenotype in peas. Students collect, analyze and interpret convergent evidence from molecular and physiological techniques. In weeks 1 and 2, students treat control and experimental plants with Gibberellic Acid (GA) to determine whether uncharacterized short mutant lines are GA responsive. These data allow students to place the mutation in the GA signal transduction pathway. During weeks 2 and 3, plants are genotyped for Mendel's "le" mutation using a derived cleaved polymorphic sequences (dCAPS) PCR assay. This laboratory allows students to make a direct connection between …


Overexpression And Gene Profiling Of Asparagine Synthetase In Hybrid Poplar, Kristopher Murray May 2015

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 …


Development Of Genetic Goat And Hamster Models Of Atrial Fibrillation And Long Qt Syndrome; And Genetic Hamster Models Of Middle East Respiratory Syndrome, Dane A. Rasmussen May 2015

Development Of Genetic Goat And Hamster Models Of Atrial Fibrillation And Long Qt Syndrome; And Genetic Hamster Models Of Middle East Respiratory Syndrome, Dane A. Rasmussen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Atrial fibrillation (AF) and long QT syndrome (LQTS) are potentially lethal heart rhythm disorders that can be caused by mutations in the potassium channel gene KCNQ1. Middle East Respiratory Syndrome (MERS) is a viral infection with the potential to replicate the devastating effects of the SARS outbreak in 2003. All three of these diseases are in need of genetic animal models.

To address these needs, my thesis project focused on the development of genetic goat and hamster models of AF and LQTS, and genetic hamster models of MERS. Because of the goat’s similar organ size/physiology and the hamster’s similar lipid …


Deciphering The Functional Collaboration Of Mid And Bric-A-Brac 2 As Potential Regulators Of Cellular Proliferation Within Adult Drosophila Ovaries, Petra Visic May 2015

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 May 2015

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 …


The Hippo Pathway Effector Yki Downregulates Wg Signaling To Promote Retinal Differentiation In The Drosophila Eye, Erika Lynn Wittkorn, Ankita Sarkar, Kristine Garcia, Madhuri Kango-Singh, Amit Singh May 2015

The Hippo Pathway Effector Yki Downregulates Wg Signaling To Promote Retinal Differentiation In The Drosophila Eye, Erika Lynn Wittkorn, Ankita Sarkar, Kristine Garcia, Madhuri Kango-Singh, Amit Singh

Biology Faculty Publications

The evolutionarily conserved Hippo signaling pathway is known to regulate cell proliferation and maintain tissue homeostasis during development. We found that activation of Yorkie (Yki), the effector of the Hippo signaling pathway, causes separable effects on growth and differentiation of theDrosophila eye. We present evidence supporting a role for Yki in suppressing eye fate by downregulation of the core retinal determination genes. Other upstream regulators of the Hippo pathway mediate this effect of Yki on retinal differentiation. Here, we show that, in the developing eye, Yki can prevent retinal differentiation by blocking morphogenetic furrow (MF) progression and R8 specification. …


A Phylogenetic Analysis Of Dictyostelium Purpureum Based On Nuclear Rdna Sequences, Mahmoud Suliman May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 …


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 Apr 2015

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 Apr 2015

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 Apr 2015

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 Apr 2015

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 Apr 2015

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 Apr 2015

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 …