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Articles 1261 - 1290 of 1702

Full-Text Articles in Genetics and Genomics

Aba Signaling Is Necessary But Not Sufficient For Rd29b Transcriptional Memory During Successive Dehydration Stresses In Arabidopsis Thaliana, Laetitia Virlouvet, Yong Ding, Hiroaki Fujii, Zoya Avramova, Michael Fromm Jan 2014

Aba Signaling Is Necessary But Not Sufficient For Rd29b Transcriptional Memory During Successive Dehydration Stresses In Arabidopsis Thaliana, Laetitia Virlouvet, Yong Ding, Hiroaki Fujii, Zoya Avramova, Michael Fromm

School of Biological Sciences: Faculty Publications

Plants subjected to a prior dehydration stress were seen to have altered transcriptional responses during a subsequent dehydration stress for up to 5 days after the initial stress. The abscisic acid (ABA) inducible RD29B gene of Arabidopsis thaliana was strongly induced after the first stress and displayed transcriptional memory with transcript levels nine-fold higher during the second dehydration stress. These increased transcript levels were due to an increased rate of transcription and are associated with an altered chromatin template during the recovery interval between the dehydration stresses. Here we use a combination of promoter deletion/substitutions, mutants in the trans-acting …


Nocturnal Homing In The Tropical Amblypygid Phrynus Pseudoparvulus (Class Arachnida, Order Amblypygi), Eileen Hebets, E.J. Gering, Verner P. Bingman, Daniel D. Wiegmann Jan 2014

Nocturnal Homing In The Tropical Amblypygid Phrynus Pseudoparvulus (Class Arachnida, Order Amblypygi), Eileen Hebets, E.J. Gering, Verner P. Bingman, Daniel D. Wiegmann

Eileen Hebets Publications

Arthropods are renowned for their navigational capabilities, with numerous examples known from insects and crustaceans. Early studies of amblypygids (Class Arachnida, Order Amblypygi) also suggest complex nocturnal navigation, despite their apparent lack of visual adaptations to the low-light conditions of a tropical understory. In a series of two studies, we use the tropical amblypygid, Phrynus pseudoparvulus, to assess their nocturnal homing ability. Our first experiment displaced and tracked resident and nonresident individuals. Resident individuals, displaced up to 4.5 m from their home refuges and released onto their home tree, were more likely to return to their previously occupied refuge than …


Detection Of Predator Cues Alters Mating Tactics In Male Wolf Spiders, Dustin J. Wilgers, Daniel Wickwire, Eileen Hebets Jan 2014

Detection Of Predator Cues Alters Mating Tactics In Male Wolf Spiders, Dustin J. Wilgers, Daniel Wickwire, Eileen Hebets

Eileen Hebets Publications

Males of the wolf spider, Rabidosa punctulata, exhibit condition-dependent alternative mating tactics, whereby small, poor condition males engage in multimodal courtship while large, good condition males adopt a direct mount tactic that forgoes courtship. This study explores the possibility that tactic-specific costs can help explain this unintuitive pattern of mating tactic expression. Specifically, we hypothesize that courtship signaling is costly with respect to eavesdropping by predators and that males can alter their tactic expression based upon the perceived environmental predation risk. We test this by first examining the risk of predation associated with different mating tactics. We use a …


H3k27me3 And H3k4me3 Chromatin Environment At Super-Induced Dehydration Stress Memory Genes Of Arabidopsis Thaliana, Ning Liu, Zoya Avramova, Michael Fromm Jan 2014

H3k27me3 And H3k4me3 Chromatin Environment At Super-Induced Dehydration Stress Memory Genes Of Arabidopsis Thaliana, Ning Liu, Zoya Avramova, Michael Fromm

School of Biological Sciences: Faculty Publications

Pre-exposure to a stress may alter the plant’s cellular, biochemical, and/or transcriptional responses during future encounters as a “memory” from the previous stress. Genes increasing transcription in response to a first dehydration stress, but producing much higher transcript levels in a subsequent stress, represent the super-induced “transcription memory” genes in Arabidopsis thaliana. The chromatin environment (histone H3 tri-methylations of Lys 4 and Lys 27, H3K4me3, and H3K27me3) studied at five dehydration stress memory genes revealed existence of distinct memory-response subclasses that responded differently to CLF deficiency and displayed different transcriptional activities during the watered recovery periods. Among the most …


Transcriptional Regulation Of Neurogenic Atrophy-Induced Gene Expression By Muscle Ring Finger-1 And Myogenic Regulatory Factors, Theodore Olson Jan 2014

Transcriptional Regulation Of Neurogenic Atrophy-Induced Gene Expression By Muscle Ring Finger-1 And Myogenic Regulatory Factors, Theodore Olson

UNF Graduate Theses and Dissertations

Skeletal muscle wasting is a consequence of numerous physiological conditions, including denervation, corticosteroid treatment, immobilization, and aging. The E3 ubiquitin ligases, MuRF1 and MAFbx, are induced under nearly all atrophy conditions and are believed to play a key role in protein degradation in atrophying muscle. However, the preliminary data described in this study provides new evidence that MuRF1 may also act as a transcriptional modulator of atrophy-induced gene activity, including the regulation of MAFbx and MuRF1 expression. To characterize the transcriptional regulation of MuRF1 and MAFbx, reporter gene constructs containing fragments of the proximal promoter regions of these genes were …


A Small Subset Of Fruitless Subesophageal Neurons Modulate Early Courtship In Drosophila, David Tran, Geoffrey Meissner, Rachael French, Bruce Baker Jan 2014

A Small Subset Of Fruitless Subesophageal Neurons Modulate Early Courtship In Drosophila, David Tran, Geoffrey Meissner, Rachael French, Bruce Baker

Faculty Publications, Biological Sciences

We show that a small subset of two to six subesophageal neurons, expressing the male products of the male courtship master regulator gene products fruitlessMale (fruM), are required in the early stages of the Drosophila melanogaster male courtship behavioral program. Loss of fruM expression or inhibition of synaptic transmission in these fruM(+) neurons results in delayed courtship initiation and a failure to progress to copulation primarily under visually-deficient conditions. We identify a fruM-dependent sexually dimorphic arborization in the tritocerebrum made by two of these neurons. Furthermore, these SOG neurons extend descending projections to the thorax and abdominal ganglia. These anatomical …


Genetic Sex Conditions And Redefining Sex, Jayce O'Shields Dec 2013

Genetic Sex Conditions And Redefining Sex, Jayce O'Shields

Student Scholarship

Western culture has a tendency to value binaries and discreet categories that separate its social structure and provide a sense of order and organization. The value placed on binaries and categories may be advantageous in some aspects, but when it starts to infringe upon the legal and medical rights of individuals not easily placed in either binary category, it can become less advantageous.

A baby is usually classified as either male or female shortly after birth, and all future legal, social, and economic actions and rights of that individual are more or less decided according to this classification. A problem …


Single Nucleotide Polymorphisms Linked To Essential Hypertension In Kasigau, Kenya, Julia Carol Freeman Dec 2013

Single Nucleotide Polymorphisms Linked To Essential Hypertension In Kasigau, Kenya, Julia Carol Freeman

Masters Theses & Specialist Projects

Hypertension, or high blood pressure (BP), is an ever-growing epidemic in the developing world. Understanding the genetics behind essential hypertension (EH), or hypertension with no known cause, is especially important. In this study, three single nucleotide polymorphisms (SNPs) known to be linked to an increase in susceptibility to EH were quantified from a cohort of Kenyans living in the Kasigau region. The SNPs are located in three genes that are part of the renin angiotensin system, the primary regulatory pathway in humans controlling BP. They include: AGT (rs699), AGTR1 (rs5186), and HSD11β2 (rs5479). Overall, by using a fluorescent-based RT-PCR technique, …


Determining Parentage And The Effects Of Relatedness On Play Partner Preference In Belding's Ground Squirrels, Jessica Weidenbach Dec 2013

Determining Parentage And The Effects Of Relatedness On Play Partner Preference In Belding's Ground Squirrels, Jessica Weidenbach

Master's Theses

I investigated 1) multiple paternity in Belding’s ground squirrels (Urocitellus beldingi) and 2) social partner preferences in juvenile U. beldingi. Prior work with blood allozymes demonstrated multiple paternity in U. beldingi litters. I evaluated paternity using microsatellite DNA analysis, which is more accurate than examining blood allozymes. My results indicate that multiple paternity in U. beldingi is more extensive than previously shown, occurring in about 90% of litters with more than one juvenile, and averaging 2.95 fathers in multiply sired litters. I also evaluated the hypothesis that play and other social behavior promotes bonding among juvenile female …


The Roles Of Phenotypic Plasticity And Genotypic Specialization In High Altitude Adaptation, Danielle M. Tufts Dec 2013

The Roles Of Phenotypic Plasticity And Genotypic Specialization In High Altitude Adaptation, Danielle M. Tufts

School of Biological Sciences: Dissertations, Theses, and Student Research

In vertebrates living at high altitude, arterial hypoxemia may be ameliorated by reversible changes in the oxygen-carrying capacity of the blood (regulated by erythropoiesis) and/or changes in blood–oxygen affinity (regulated by allosteric effectors of hemoglobin function). These hematological traits often differ between taxa that are native to different elevational zones, but it is often unknown whether the observed physiological differences reflect fixed, genetically based differences or environmentally induced acclimatization responses (phenotypic plasticity). Here, we report measurements of hematological traits related to blood–O2 transport in populations of deer mice (Peromyscus maniculatus) that are native to high- and low-altitude …


Reflections On The Cost Of "Low-Cost" Whole Genome Sequencing: Framing The Health Policy Debate, Timothy Caulfield, Jim Evans, Amy Mcguire, Christopher Mccabe, Tania M. Bubela, Robert Cook-Deegan, Jennifer Fishman, Stuart Hogarth, Fiona A. Miller, Vardit Ravitsky Nov 2013

Reflections On The Cost Of "Low-Cost" Whole Genome Sequencing: Framing The Health Policy Debate, Timothy Caulfield, Jim Evans, Amy Mcguire, Christopher Mccabe, Tania M. Bubela, Robert Cook-Deegan, Jennifer Fishman, Stuart Hogarth, Fiona A. Miller, Vardit Ravitsky

Office of the Provost

The cost of whole genome sequencing is dropping rapidly. There has been a great deal of enthusiasm about the potential for this technological advance to transform clinical care. Given the interest and significant investment in genomics, this seems an ideal time to consider what the evidence tells us about potential benefits and harms, particularly in the context of health care policy. The scale and pace of adoption of this powerful new technology should be driven by clinical need, clinical evidence, and a commitment to put patients at the centre of health care policy.


Novel Neuroprotective Function Of Apical-Basal Polarity Genecrumbs In Amyloid Beta 42 (Aβ42) Mediated Neurodegeneration, Andrew Steffensmeier, Meghana Tare, Oorvashi Roy Puli, Rohan Modi, Jaison Nainaparampil, Madhuri Kango-Singh, Amit Singh Nov 2013

Novel Neuroprotective Function Of Apical-Basal Polarity Genecrumbs In Amyloid Beta 42 (Aβ42) Mediated Neurodegeneration, Andrew Steffensmeier, Meghana Tare, Oorvashi Roy Puli, Rohan Modi, Jaison Nainaparampil, Madhuri Kango-Singh, Amit Singh

Biology Faculty Publications

Alzheimer's disease (AD, OMIM: 104300), a progressive neurodegenerative disorder with no cure to date, is caused by the generation of amyloid-beta-42 (Aβ42) aggregates that trigger neuronal cell death by unknown mechanism(s). We have developed a transgenic Drosophilaeye model where misexpression of human Aβ42 results in AD-like neuropathology in the neural retina. We have identified an apical-basal polarity gene crumbs (crb) as a genetic modifier of Aβ42-mediated-neuropathology. Misexpression of Aβ42 caused upregulation of Crb expression, whereas downregulation of Crb either by RNAi or null allele approach rescued the Aβ42-mediated-neurodegeneration. Co-expression of full length Crb with Aβ42 increased severity of Aβ42-mediated-neurodegeneration, …


Homeotic Gene Teashirt (Tsh) Has A Neuroprotective Function In Amyloid-Beta 42 Mediated Neurodegeneration, Michael T. Moran, Meghana Tare, Madhuri Kango-Singh, Amit Singh Nov 2013

Homeotic Gene Teashirt (Tsh) Has A Neuroprotective Function In Amyloid-Beta 42 Mediated Neurodegeneration, Michael T. Moran, Meghana Tare, Madhuri Kango-Singh, Amit Singh

Biology Faculty Publications

Background: Alzheimer's disease (AD) is a debilitating age related progressive neurodegenerative disorder characterized by the loss of cognition, and eventual death of the affected individual. One of the major causes of AD is the accumulation of Amyloid-beta 42 (Aβ42) polypeptides formed by the improper cleavage of amyloid precursor protein (APP) in the brain. These plaques disrupt normal cellular processes through oxidative stress and aberrant signaling resulting in the loss of synaptic activity and death of the neurons. However, the detailed genetic mechanism(s) responsible for this neurodegeneration still remain elusive.

Methodology/Principal Findings: We have generated a transgenic Drosophila eye model where …


Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs Oct 2013

Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Set1 complex, a histone methyltransferase complex found in S. cerevisiae (budding yeast), is the only histone methyltransferase responsible for catalyzing methylation of histone H3 at Lysine 4. It possesses homologues in other species, humans included. While yeast only have the Set1 complex, the human homologues of the yeast Set1 complex include mixed-lineage leukemia family (MLL1-4), Set1 A, Set1 B, among others. MLL1-4 has been shown to play a role in transcription, cell type specification, and the development of leukemia. One application of characterizing the role of a protein is that the information gained can provide insight into the function …


Fast Quantitative Real-Time Pcr-Based Screening For Common Chromosomal Aneuploidies In Mouse Embryonic Stem Cells, Charlotte D'Hulst, Irena Parvanova, Delia Tomoiaga, Maria L. Sapar, Paul Feinstein Sep 2013

Fast Quantitative Real-Time Pcr-Based Screening For Common Chromosomal Aneuploidies In Mouse Embryonic Stem Cells, Charlotte D'Hulst, Irena Parvanova, Delia Tomoiaga, Maria L. Sapar, Paul Feinstein

Publications and Research

Chromosomal integrity has been known for many years to affect the ability of mouse embryonic stem cells (mESCs) to contribute to the germline of chimeric mice. Abnormal chromosomes are generally detected by standard cytogenetic karyotyping. However, this method is expensive, time consuming, and often omitted prior to blastocyst injection, consequently reducing the frequency of mESC-derived offspring. Here, we show a fast, accurate, and inexpensive screen for identifying the two most common aneuploidies (Trisomy 8 and loss of chromosome Y) in genetically manipulated mESCs using quantitative real-time PCR (qPCR). Screening against these two aneuploidies significantly increases the fraction of normal mESC …


Signatures Of Rapid Evolution In Urban And Rural Transcriptomes Of White-Footed Mice (Peromyscus Leucopus) In The New York Metropolitan Area, Stephen Edward Harris, Jason Munshi-South, Craig Oberfell, Rachel O'Neill Aug 2013

Signatures Of Rapid Evolution In Urban And Rural Transcriptomes Of White-Footed Mice (Peromyscus Leucopus) In The New York Metropolitan Area, Stephen Edward Harris, Jason Munshi-South, Craig Oberfell, Rachel O'Neill

Publications and Research

Urbanization is a major cause of ecological degradation around the world, and human settlement in large cities is accelerating. New York City (NYC) is one of the oldest and most urbanized cities in North America, but still maintains 20% vegetation cover and substantial populations of some native wildlife. The white-footed mouse, Peromyscus leucopus, is a common resident of NYC’s forest fragments and an emerging model system for examining the evolutionary consequences of urbanization. In this study, we developed transcriptomic resources for urban P. leucopus to examine evolutionary changes in protein-coding regions for an exemplar “urban adapter.” We used Roche 454 …


Genome-Wide Analyses Of Shavenbaby Target Genes Reveals Distinct Features Of Enhancer Organization, Delphine Menoret, Marc Santolini, Isabelle Fernandes, Rebecca Spokony, Jennifer Zanet, Ignacio Gonzalez, Yvan Latapie, Pierre Ferrer, Hervé Rouault, Kevin P. White, Philippe Besse, Vincent Hakim, Stein Aerts, Francois Payre, Serge Plaza Aug 2013

Genome-Wide Analyses Of Shavenbaby Target Genes Reveals Distinct Features Of Enhancer Organization, Delphine Menoret, Marc Santolini, Isabelle Fernandes, Rebecca Spokony, Jennifer Zanet, Ignacio Gonzalez, Yvan Latapie, Pierre Ferrer, Hervé Rouault, Kevin P. White, Philippe Besse, Vincent Hakim, Stein Aerts, Francois Payre, Serge Plaza

Publications and Research

Background: Developmental programs are implemented by regulatory interactions between Transcription Factors (TFs) and their target genes, which remain poorly understood. While recent studies have focused on regulatory cascades of TFs that govern early development, little is known about how the ultimate effectors of cell differentiation are selected and controlled. We addressed this question during late Drosophila embryogenesis, when the finely tuned expression of the TF Ovo/Shavenbaby (Svb) triggers the morphological differentiation of epidermal trichomes.

Results: We defined a sizeable set of genes downstream of Svb and used in vivo assays to delineate 14 enhancers driving their specific expression in trichome …


A Study On The Regulation Of Amino Acids And Glucose Sensing Pathways In Saccharomyces Cerevisiae, Mengying Chiang Aug 2013

A Study On The Regulation Of Amino Acids And Glucose Sensing Pathways In Saccharomyces Cerevisiae, Mengying Chiang

LSU New Orleans Theses and Dissertations

Nutrient availability regulates eukaryotic cell growth. This study focuses on two signaling pathways, involved in sensing amino acids and carbon sources, which allow cells to respond appropriately to their presence. The first part of this study shows that Ssy1, a plasma membrane localized sensor in the Ssy1-Ptr3-Ssy5 (SPS) amino acid sensing pathway, can detect 19 common L-amino acids with different potencies and affinities based on the physiochemical structure of amino acids. Substituents around alpha carbon are critical for amino acid sensing by Ssy1. Furthermore, a high concentration of cysteine is toxic to cells. Inactivation of SPS signaling confers resistance to …


Identifying Molecular Markers Associated With Salt And Boron Tolerance In Poplar Trees, Darshanpreet Gill, Nathan Follen, Davis W. Cheng, Kyan Salehi, Gary Banuelos, James P. Prince Aug 2013

Identifying Molecular Markers Associated With Salt And Boron Tolerance In Poplar Trees, Darshanpreet Gill, Nathan Follen, Davis W. Cheng, Kyan Salehi, Gary Banuelos, James P. Prince

STAR Program Research Presentations

Standard irrigation practices promote salt and boron accumulation in soils on the Westside of Central California. The build-up of these inorganic salts leads to the degradation of arable land and reduction of crop production. Different clones of poplar trees have been shown to grow in salt- and boron-contaminated soils, and in doing so, gradually remove significant amounts of these inorganic salts from the soil. In an effort to identify molecular markers linked with salt and boron tolerance in poplars, 31 PCR primer pairs have been designed based on candidate genes identified from the literature, and an additional 31 PCR primer …


Defining The Requirements For Early Gene Expression In Bacteriophage Hk639, Amanda L. Seaton Aug 2013

Defining The Requirements For Early Gene Expression In Bacteriophage Hk639, Amanda L. Seaton

Masters Theses & Specialist Projects

Lambdoid phages suppress transcription termination to fully express their genes. Antitermination of early gene expression in most lambdoid phages is mediated by an interaction between the N protein and a number of host-encoded factors. Bacteriophage HK022 does not rely on a protein for antitermination. To promote full expression of early phage genes, the transcripts of the HK022 put sites interact directly with RNA polymerase to convert it to a termination resistant form. Bacteriophage HK639 also uses RNA-mediated antitermination. However, it only possesses a single put-like element in its left operon. Because most lambdoid phages, including HK022, have antiterminator elements in …


Development Of Tools To Assess The Effects Of Lunasin On Normal Development And Tumor Progression In Drosophila Melanogaster, Gillian E. Jones Aug 2013

Development Of Tools To Assess The Effects Of Lunasin On Normal Development And Tumor Progression In Drosophila Melanogaster, Gillian E. Jones

Masters Theses & Specialist Projects

Soy contains many bioactive molecules known to elicit anti-cancer effects. One such peptide, Lunasin, has been shown to selectively act on newly transformed cells while having no cytotoxic effect on non-tumorigenic or established cancer cell lines. In this study we attempt to understand the developmental effects of Lunasin overexpression in vivo and create reagents that will help us understand Lunasin’s anti tumorigenic effects in an intact organism. cDNA encoding lunasin and EGFP-lunasin were cloned into pUAST and microinjected into Drosophila embryos. Tissue-specific overexpression of EGFP-Lun in the resulting transgenic lines was accomplished by crossing transgenics to various GAL4 driver lines. …


The Importance Of Epigenetic Phenomena In Regulating Activity Of The Genetic Material, Sin Chan Aug 2013

The Importance Of Epigenetic Phenomena In Regulating Activity Of The Genetic Material, Sin Chan

Senior Honors Projects

Genetics has taught us that genes are represented as discrete sequences within a larger DNA molecule found embedded within the chromosomes of a living cell. Collectively these chromosomes and their associated genes carry all of the instructions for life. Until recently, the prevailing thought has been that genes are destiny in the life of an individual since the genes carry the information that determines the general traits and characteristics associated with that individual. The relatively recent understanding of mechanisms that underlie epigenetic phenomena has led to a rethinking of this concept. Epigenetics describes cellular mechanisms that explain how two individuals …


Recurrent Modification Of A Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity, William A. Rogers, Joseph R. Salomone, David J. Tacy, Eric M. Camino, Kristen A. Davis, Mark Rebeiz, Thomas M. Williams Aug 2013

Recurrent Modification Of A Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity, William A. Rogers, Joseph R. Salomone, David J. Tacy, Eric M. Camino, Kristen A. Davis, Mark Rebeiz, Thomas M. Williams

Biology Faculty Publications

The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE), little is known about the mutational and molecular paths of parallel CRE evolution. InDrosophila melanogaster fruit flies, the Bric-à-brac (Bab) transcription factors control the development …


Prkca: Identification Of A Novel Downstream Target Of Wt1, Devin Jones Aug 2013

Prkca: Identification Of A Novel Downstream Target Of Wt1, Devin Jones

Dissertations and Theses (Open Access)

Wilms tumor is a childhood tumor of the kidney arising from the undifferentiated metanephric mesenchyme. Tumorigenesis is attributed to a number of genetic and epigenetic alterations. In 20% of Wilms tumors, Wilms tumor gene 1 (WT1) undergoes inactivating homozygous mutations causing loss of function of the zinc finger transcription factor it encodes. It is hypothesized that mutations in WT1 result in dysregulation of downstream target genes, leading to aberrant kidney development and/or Wilms tumor. These downstream target genes are largely unknown, and identification is important for further understanding Wilms tumor development. Heatmap data of human Wilms tumor protein …


The Rate And Effects Of Spontaneous Mutation On Fitness Traits In The Social Amoeba, Dictyostelium Discoideum, David W. Hall, Sara Fox, Jennie J. Kuzdzal-Fick, Joan E. Strassmann, David C. Queller Jul 2013

The Rate And Effects Of Spontaneous Mutation On Fitness Traits In The Social Amoeba, Dictyostelium Discoideum, David W. Hall, Sara Fox, Jennie J. Kuzdzal-Fick, Joan E. Strassmann, David C. Queller

Biology Faculty Research

We performed a mutation accumulation (MA) experiment in the social amoeba Dictyostelium discoideum to estimate the rate and distribution of effects of spontaneous mutations affecting eight putative fitness traits. We found that the per-generation mutation rate for most fitness components is 0.0019 mutations per haploid genome per generation or larger. This rate is an order of magnitude higher than estimates for fitness components in the unicellular eukaryote Saccharomyces cerevisiae, even though the base-pair substitution rate is two orders of magnitude lower. The high rate of fitness-altering mutations observed in this species may be partially explained by a large mutational target …


Evolution Of A Higher Intracellular Oxidizing Environment In Caenorhabditis Elegans Under Relaxed Selection, Joanna Joyner-Matos, Kiley A. Hicks, Dustin Cousins, Michelle Keller, Dee R. Denver, Charles F. Baer, Suzanne Estes Jun 2013

Evolution Of A Higher Intracellular Oxidizing Environment In Caenorhabditis Elegans Under Relaxed Selection, Joanna Joyner-Matos, Kiley A. Hicks, Dustin Cousins, Michelle Keller, Dee R. Denver, Charles F. Baer, Suzanne Estes

Biology Faculty Publications and Presentations

We explored the relationship between relaxed selection, oxidative stress, and spontaneous mutation in a set of mutationaccumulation (MA) lines of the nematode Caenorhabditis elegans and in their common ancestor. We measured steady-state levels of free radicals and oxidatively damaged guanosine nucleosides in the somatic tissues of five MA lines for which nuclear genome base substitution and GC-TA transversion frequencies are known. The two markers of oxidative stress are highly correlated and are elevated in the MA lines relative to the ancestor; point estimates of the per-generation rate of mutational decay (DM) of these measures of oxidative stress are similar to …


Science Fiction And The Myth Of Trajectory Evolution, Jocelyn D. Pickreign Jun 2013

Science Fiction And The Myth Of Trajectory Evolution, Jocelyn D. Pickreign

The Macalester Review

Stephen Jay Gould first proposed the idea of “iconographies of progress.” Today, one of the most prominent forms of progress iconography is the science fiction story. Science fiction as a genre frequently portrays evolution as a linear trajectory of increasing complexity, and in doing so, furthers a worldview that is not unlike the pre-Darwin understanding of human beings as both the center and the pinnacle of the natural world.


Review Of "Translational Stem Cell Research: Issues Beyond The Debate On The Moral Status Of The Human Embryo" Edited By K. Hug And G. Hermerén, John B. Jenkins Jun 2013

Review Of "Translational Stem Cell Research: Issues Beyond The Debate On The Moral Status Of The Human Embryo" Edited By K. Hug And G. Hermerén, John B. Jenkins

Biology Faculty Works

No abstract provided.


Investigating Potential Target Genes Of The Rfx Transcription Factor Daf-19 In Caenorhabditis Elegans, He Zhang May 2013

Investigating Potential Target Genes Of The Rfx Transcription Factor Daf-19 In Caenorhabditis Elegans, He Zhang

Lawrence University Honors Projects

Neurodegenerative diseases, such as Alzheimer’s disease, are characterized by an age-related decrease in the synaptic activity of the patient’s brain. Previous research suggested that a RFX transcription factor DAF-19 in the nematode Caenorhabditis elegans (C. elegans) may be involved in the maintenance of synaptic protein levels. Particularly, worms that were DAF-19A/B defective showed reduced synaptic activities when compared to their age-matched controls.

This study investigated the role of DAF-19A/B isoforms in the C. elegans nervous system. Three genes, F46G11.3, F57B10.9, and F58E2.3 were selected as potential downstream targets of DAF-19A/B based on their potential neuronal expression. …


Occurrence And Genetic Diversity Of Lemon Sharks (Negaprion Brevirostris) At A Nursery Ground At The Chandeleur Islands, Louisiana., Jonathan F. Mckenzie May 2013

Occurrence And Genetic Diversity Of Lemon Sharks (Negaprion Brevirostris) At A Nursery Ground At The Chandeleur Islands, Louisiana., Jonathan F. Mckenzie

LSU New Orleans Theses and Dissertations

Anecdotal evidence suggested that immature lemon sharks (Negaprion brevirostris) occur at the Chandeleur Islands in southeastern Louisiana. From May 2009 to August 2011, the Nekton Research Laboratory at the University of New Orleans regularly sampled habitats at the Chandeleur Islands to confirm the presence of immature individuals of this species. During these efforts, 147 immature lemon sharks (neonates, young-of-the-year, and juveniles) were collected. Each shark was PIT tagged and a tissue sample was taken for genetic analyses. Sizes ranged from 56 – 177 cm total length. Sharks showed a preference for sandy substrate and smaller individuals showed significant preference …