Life Sciences Commons^™

A Description Of Tolerance To Apical Meristem Damage In Wild Populations Of Arabidopsis Thaliana And Its Genetic Basis, Justin Dalrymple

Biology Theses

Since plants cannot actively avoid herbivory, they rely on two primary strategies to maintain their fitness in the face of herbivore pressure: resistance—the deterrence of herbivory via physical and chemical means—and tolerance—recuperation of aboveground mass after herbivory. Although diverse groups have been shown to be tolerant to herbivory, mechanisms of tolerance are not yet well known. There is also very little known about the ecological relevance of tolerance strategies in wild populations. In Arabidopsis thaliana, the apical meristem suppresses growth of axillary meristems to a high degree under normal conditions, but a number of axillary meristemswill grow after apical meristem …

Using Phylogenetically-Informed Annotation (Pia) To Search For Light-Interacting Genes In Transcriptomes From Non-Model Organisms, Daniel L. Speiser, Molly S. Pankey, Alexander K. Zaharoff, Barbara A. Battelle, Heather D. Bracken-Grissom, Jesse W. Breinholt, Seth M. Bybee, Thomas W. Cronin, Anders Garm, Annie R. Lindgren, Nipam H. Patel, Megan L. Porter, Meredith E. Protas, Ajna S. Rivera, Jeanne M. Serb, Kirk S. Zigler, Keith A. Crandall, Todd H. Oakley

Biology Faculty Publications and Presentations

Background: Tools for high throughput sequencing and de novo assembly make the analysis of transcriptomes (i.e. the suite of genes expressed in a tissue) feasible for almost any organism. Yet a challenge for biologists is that it can be difficult to assign identities to gene sequences, especially from non-model organisms. Phylogenetic analyses are one useful method for assigning identities to these sequences, but such methods tend to be time-consuming because of the need to re-calculate trees for every gene of interest and each time a new data set is analyzed. In response, we employed existing tools for phylogenetic analysis to …

Social Immunity And The Expression Of Immune-Related Genes In The Eastern Subterranean Termite, Qi Gao

Electronic Thesis and Dissertation Repository

Individuals living within social groups may benefit from the efficiencies of division of labour, but on the other hand render themselves vulnerable to socially transmitted disease. This cost to social living should promote cooperative barriers to disease transmission, especially in eusocial taxa where spatial and genetic proximity to nestmates are characteristically pronounced. Though studies of the immunity at multiple levels in social species are becoming more common, little is known about how their sociality is deployed to resist contagion. By exposing the Eastern subterranean termite Reticulitermes flavipes to entomopathogenic fungi, I studied their immune responses at multiple levels. At the …

Limited Sex-Biased Neural Gene Expression Patterns Across Strains In Zebrafish (Danio Rerio), Ryan Y. Wong, Melissa M. Mcleod, John Godwin

Biology Faculty Publications

Background: Male and female vertebrates typically differ in a range of characteristics, from morphology to physiology to behavior, which are influenced by factors such as the social environment and the internal hormonal and genetic milieu. However, sex differences in gene expression profiles in the brains of vertebrates are only beginning to be understood. Fishes provide a unique complement to studies of sex differences in mammals and birds given that fish show extreme plasticity and lability of sexually dimorphic characters and behaviors during development and even adulthood. Hence, teleost models can give additional insight into sexual differentiation. The goal of …

Exploring The Complexity Of Intellectual Disability In Fetal Alcohol Spectrum Disorders, Aniruddho Chokroborty-Hoque, Bonnie Alberry, Shiva M. Singh

Biology Publications

Brain development in mammals is long lasting. It begins early during embryonic growth and is finalized in early adulthood. This progression represents a delicate choreography of molecular, cellular, and physiological processes initiated and directed by the fetal genotype in close interaction with environment. Not surprisingly, most aberrations in brain functioning including intellectual disability (ID) are attributed to either gene(s), or environment or the interaction of the two. The ensuing complexity has made the assessment of this choreography, ever challenging. A model to assess this complexity has used a mouse model (C57BL/6J or B6) that is subjected to prenatal alcohol exposure. …

Auxin Input Pathway Disruptions Are Mitigated By Changes In Ausin Biosynthetic Gene Expression In Arabidopsis, Gretchen M. Spiess, Amanda Hausman, Peng Yu, Jerry D. Cohen, Rebekah A. Rampey, Bethany K. Zolman

Biology Faculty Research and Publications

Auxin is a phytohormone involved in cell elongation and division. Levels of indole-3-acetic acid (IAA), the primary auxin, are tightly regulated through biosynthesis, degradation, sequestration, and transport. IAA is sequestered in reversible processes by adding amino acids, polyol or simple alcohols, or sugars, forming IAA conjugates, or through a two-carbon elongation forming indole-3-butyric acid. These sequestered forms of IAA alter hormone activity. To gain a better understanding of how auxin homeostasis is maintained, we have generated Arabidopsis (Arabidopsis tlnaliana) mutants that combine disruptions in the pathways, converting IAA conjugates and indole-3-butyric acid to free IAA. These mutants show phenotypes indicative …

Expression Patterns Of Aba And Ga Metabolism Genes And Hormone Levels During Rice Seed Development And Imbibition: A Comparison Of Dormant And Non-Dormant Rice Cultivars, Yang Liu, Jun Fang, Fan Xu, Jinfang Chu, Cunyu Yan, Michael Schläppi, Youping Wang, Chengcai Chu

Biological Sciences Faculty Research and Publications

Seed dormancy is an important agronomic trait in cereals. Using deep dormant (N22), medium dormant (ZH11), and non-dormant (G46B) rice cultivars, we correlated seed dormancy phenotypes with abscisic acid (ABA) and gibberellin (GA) metabolism gene expression profiles and phytohormone levels during seed development and imbibition. A time course analysis of ABA and GA content during seed development showed that N22 had a high ABA level at early and middle seed developmental stages, while at late developmental stage it declined to the level of ZH11; however, its ABA/GA ratio maintained at a high level …

Long-Term Genomic And Epigenomic Dysregulation As A Consequence Of Prenatal Alcohol Exposure: A Model For Fetal Alcohol Spectrum Disorders, Morgan L Kleiber, Eric J Diehl, Benjamin I Laufer, Katarzyna Mantha, Aniruddho Chokroborty-Hoque, Bonnie Alberry, Shiva M Singh

Biology Publications

There is abundant evidence that prenatal alcohol exposure leads to a range of behavioral and cognitive impairments, categorized under the term fetal alcohol spectrum disorders (FASDs). These disorders are pervasive in Western cultures and represent the most common preventable source of neurodevelopmental disabilities. The genetic and epigenetic etiology of these phenotypes, including those factors that may maintain these phenotypes throughout the lifetime of an affected individual, has become a recent topic of investigation. This review integrates recent data that has progressed our understanding FASD as a continuum of molecular events, beginning with cellular stress response and ending with a long-term …

The Effects Of Jasmonic Acid And Chemicals In The Ja Pathway On The Defense Systems And Gene Expression In Moss, Physcomitrella Patens And Amblystegium Serpens, Allison Shanks

Undergraduate Honors Thesis Collection

Systemic acquired resistance (SAR) is a defense system used by plants that results in increased resistance to future pathogen infection following an initial pathogen exposure. SAR in vascular plants has been well documented; however, a similar defense system has only recently been documented in non-vascular plants. It is believed that chemicals in the jasmonic acid (JA) pathway are able to activate the SAR response in vascular plants. The non-vascular plant, Amb/ystegium serpens, will be used as a model to test if SAR is triggered by JA and two other molecules in the JA pathway, 12-oxo-phytodieonic acid, and methyl jasmonate. To …

P53 Maintains Hepatic Cell Identity During Liver Regeneration, Zeynep Hande Coban Akdemir

Dissertations & Theses (Open Access)

p53 MAINTAINS HEPATIC CELL IDENTITY DURING LIVER REGENERATION

Zeynep Hande Coban Akdemir, B.S.,M.A.

Advisory Professor: Michelle Craig Barton, Ph.D.

p53 is a tumor suppressor that has been well studied in tumor-derived, cultured cells. However, its functions in normal proliferating cells and tissues are generally overlooked. We propose that p53 functions during the G1-S transition can be studied in normal, differentiated cells during surgery-induced liver regeneration. Two-thirds partial hepatectomy (PH) of mouse liver offers a unique model to compare p53 functions in regenerating versus sham (control) cells. My hypothesis is that intersection of global expression analyses (microarray and RNA sequencing) and …

Transcriptional Control Of Toxoplasma Development, Joshua Byran Radke

USF Tampa Graduate Theses and Dissertations

Toxoplasma gondii is an obligate intracellular protozoan parasite of animals and man. The asexual life cycle of Toxoplasma involves three very distinct, but tightly coordinated developmental stages. In nature, the sporozoite (contained within an oocyst) and bradyzoite (contained within a tissue cyst) initiate infection of the intermediate host, followed by rapid differentiation into the actively replicating tachyzoite. When countered by an effective host response, the tachyzoite differentiates back into the latent bradyzoite and this unique ability of Toxoplasma to interconvert between the replicating tachyzoite and the latent bradyzoite within a single host is the cause of life long infection. The …

Hp1a: A Structural Chromosomal Protein Regulating Transcription, Joel Eissenberg, Sarah C.R. Elgin

Biology Faculty Publications & Presentations

Heterochromatin protein 1 (HP1a in Drosophila) is a conserved eukaryotic chromosomal protein that is prominently associated with pericentric heterochromatin and mediates the concomitant gene silencing. Mechanistic studies implicate HP1 family proteins as 'hub proteins,' able to interact with a variety of chromosomal proteins through the chromo-shadow domain (CSD), as well as to recognize key histone modification sites [primarily histone H3 di/trimethyl Lys9 (H3K9me2/3)] through the chromodomain (CD). Consequently, HP1 has many important roles in chromatin architecture and impacts both gene expression and gene silencing, utilizing a variety of mechanisms. Clearly, HP1 function is altered by context, and potentially by post-translational …

Transcriptome Analysis Of Listeria Monocytogenes Exposed To Biocide Stress Reveals A Multi-System Response Involving Cell Wall Synthesis, Sugar Uptake, And Motility, Aidan Casey, Edward M. Fox, Stephan Schmitz-Esser, Aidan Coffey, Olivia Mcauliffe, Kieran Jordan

Department of Biological Sciences Publications

Listeria monocytogenes is a virulent food-borne pathogen most often associated with the consumption of “ready-to-eat” foods. The organism is a common contaminant of food processing plants where it may persist for extended periods of time. A commonly used approach for the control of Listeria monocytogenes in the processing environment is the application of biocides such as quaternary ammonium compounds. In this study, the transcriptomic response of a persistent strain of L. monocytogenes (strain 6179) on exposure to a sub-lethal concentration of the quaternary ammonium compound benzethonium chloride (BZT) was assessed. Using RNA-Seq, gene expression levels were quantified by sequencing …