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2011

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Articles 91 - 120 of 1064

Full-Text Articles in Biology

Minimizing Bias In Biomass Allometry: Model Selection And Log‐Transformation Of Data, Joseph Mascaro, Creighton M. Litton, R. Flint Hughes, Amanda Uowolo, Stefan A. Schnitzer Nov 2011

Minimizing Bias In Biomass Allometry: Model Selection And Log‐Transformation Of Data, Joseph Mascaro, Creighton M. Litton, R. Flint Hughes, Amanda Uowolo, Stefan A. Schnitzer

Biological Sciences Faculty Research and Publications

Nonlinear regression is increasingly used to develop allometric equations for forest biomass estimation (i.e., as opposed to the traditional approach of log‐transformation followed by linear regression). Most statistical software packages, however, assume additive errors by default, violating a key assumption of allometric theory and possibly producing spurious models. Here, we show that such models may bias stand‐level biomass estimates by up to 100 percent in young forests, and we present an alternative nonlinear fitting approach that conforms with allometric theory.


Alarm-Calling And Response Behaviors Of The Black-Tailed Prairie Dog In Kansas, Lloyd W. Towers Iii Nov 2011

Alarm-Calling And Response Behaviors Of The Black-Tailed Prairie Dog In Kansas, Lloyd W. Towers Iii

Master's Theses or Doctor of Nursing Practice

Prairie dogs (Cynomys spp.) use alarm calls to warn offspring and other kin of predatory threats. Dialects occur when vocalizations contain consistent differences among populations not isolated by geographic barriers. The Gunnison’s prairie dog (C. gunnisoni) has dialects in its alarm calls. The objectives of my study were to: (1) assess if the black-tailed prairie dog (C. ludovicianus) responded differently to alarm calls from other colonies than it did to alarm calls from its own colony, and (2) detect dialects, if they existed, in the alarm calls of the black-tailed prairie dog. The study included 8 black-tailed prairie dog colonies …


Gravesoil Microbial Community Structure During Carcass Decomposition, Amy E. Maile Nov 2011

Gravesoil Microbial Community Structure During Carcass Decomposition, Amy E. Maile

Department of Entomology: Dissertations, Theses, and Student Research

Dead bodies placed on soil represent unique challenges for investigators. Although processes in soils can be used to estimate postmortem interval, we know very little about how carcasses and insects affect gravesoil microbial communities.

To address this, the current project was composed of two experiments. Experiment one was conducted to investigate the effect of surface type on carcass decomposition and evaluate soil ecology methods. Experiment two was conducted to investigate the presence of an insect population (Lucilia sericata Meigen) on gravesoil microbial communities. Both experiments were conducted in a laboratory setting using freshly killed mouse carcasses. Mouse carcasses were …


Evolution Of Functionally Diverse Alleles Associated With Ptc Bitter Taste Sensitivity In Africa, Michael Campbell Nov 2011

Evolution Of Functionally Diverse Alleles Associated With Ptc Bitter Taste Sensitivity In Africa, Michael Campbell

Department of Biology Faculty Publications

Although human bitter taste perception is hypothesized to be a dietary adaptation, little is known about genetic signatures of selection and patterns of bitter taste perception variability in ethnically diverse populations with different diets, particularly from Africa. To better understand the genetic basis and evolutionary history of bitter taste sensitivity, we sequenced a 2,975 bp region encompassing TAS2R38, a bitter taste receptor gene, in 611 Africans from 57 populations in West Central and East Africa with diverse subsistence patterns, as well as in a comparative sample of 132 non-Africans. We also examined the association between genetic variability at this locus …


Laboratory Diagnosis Of Clostridium Difficile Infection: Can Molecular Amplification Methods Move Us Out Of Uncertainty?, Fred C. Tenover, Ellen Jo Baron, Lance R. Peterson, David Persing Nov 2011

Laboratory Diagnosis Of Clostridium Difficile Infection: Can Molecular Amplification Methods Move Us Out Of Uncertainty?, Fred C. Tenover, Ellen Jo Baron, Lance R. Peterson, David Persing

Biology Faculty Publications

The laboratory diagnosis of Clostridium difficile infection (CDI) continues to be challenging. Recent guidelines from professional societies in the United States note that enzyme immunoassays for toxins A and B do not have adequate sensitivity to be used alone for detecting CDI, yet the optimal method for diagnosing this infection remains unclear. Nucleic acid amplification tests (NAATs) that target chromosomal toxin genes (usually the toxin B gene, tcdB) show high sensitivity and specificity, provide rapid results, and are amenable to both batch and on-demand testing, but these tests were not universally recommended for routine use in the recent guidelines. …


Competencies: A Cure For Pre-Med Curriculum, Winston Anderson, Richard Amasino, Manuel Ares, Utpal Banerjee, Bonnie Bartel, Victor Corces, Catherine Drennan, Sarah C.R. Elgin, Irving Epstein, Ellen Fanning, Louis Guillette, Jo Handelsman, Graham Hatfull, Ronald Hoy, Darcy Kelley, Leslie Leinwand, Richard Losick, Yi Lu, David Lynn, Claudia Neuhauser, Diane O'Dowd, Toto Olivera, Pavel Pevzner, Rebecca Richards-Kortum, Jasper Rine, Robert Sah, Scott Strobel, Graham Walker, David Walt, Isiah Warner, Sue Wessler, Huntington Willard, Richard Zare Nov 2011

Competencies: A Cure For Pre-Med Curriculum, Winston Anderson, Richard Amasino, Manuel Ares, Utpal Banerjee, Bonnie Bartel, Victor Corces, Catherine Drennan, Sarah C.R. Elgin, Irving Epstein, Ellen Fanning, Louis Guillette, Jo Handelsman, Graham Hatfull, Ronald Hoy, Darcy Kelley, Leslie Leinwand, Richard Losick, Yi Lu, David Lynn, Claudia Neuhauser, Diane O'Dowd, Toto Olivera, Pavel Pevzner, Rebecca Richards-Kortum, Jasper Rine, Robert Sah, Scott Strobel, Graham Walker, David Walt, Isiah Warner, Sue Wessler, Huntington Willard, Richard Zare

Biology Faculty Research

No abstract provided.


Former Andrews Professor Ministers To Eunuchs Of India, Ashleigh Jardine Nov 2011

Former Andrews Professor Ministers To Eunuchs Of India, Ashleigh Jardine

Lake Union Herald

No abstract provided.


Linking Fruit Traits To Variation In Predispersal Vertebrate Seed Predation, Insect Seed Predation, And Pathogen Attack, Noelle G. Beckman, Helene C. Muller-Landau Nov 2011

Linking Fruit Traits To Variation In Predispersal Vertebrate Seed Predation, Insect Seed Predation, And Pathogen Attack, Noelle G. Beckman, Helene C. Muller-Landau

Biology Faculty Publications

The importance of vertebrates, invertebrates, and pathogens for plant communities has long been recognized, but their absolute and relative importance in early recruitment of multiple coexisting tropical plant species has not been quantified. Further, little is known about the relationship of fruit traits to seed mortality due to natural enemies in tropical plants. To investigate the influences of vertebrates, invertebrates, and pathogens on reproduction of seven canopy plant species varying in fruit traits, we quantified reductions in fruit development and seed germination due to vertebrates, invertebrates, and fungal pathogens through experimental removal of these enemies using canopy exclosures, insecticide, and …


Temperature, Recreational Fishing And Diapause Egg Connections: Dispersal Of Spiny Water Fleas (Bythotrephes Longimanus), W. Charles Kerfoot, Foad Yousef, Martin M. Hobmeier, Ryan P. Maki, S. Taylor Jarnagin, James H. Churchill Nov 2011

Temperature, Recreational Fishing And Diapause Egg Connections: Dispersal Of Spiny Water Fleas (Bythotrephes Longimanus), W. Charles Kerfoot, Foad Yousef, Martin M. Hobmeier, Ryan P. Maki, S. Taylor Jarnagin, James H. Churchill

Michigan Tech Publications, Part 1

The spiny water flea (Bythotrephes longimanus) is spreading from Great Lakes coastal waters into northern inland lakes within a northern temperature-defined latitudinal band. Colonization of Great Lakes coastal embayments is assisted by winds and seiche surges, yet rapid inland expansion across the northern states comes through an overland process. The lack of invasions at Isle Royale National Park contrasts with rapid expansion on the nearby Keweenaw Peninsula. Both regions have comparable geology, lake density, and fauna, but differ in recreational fishing boat access, visitation, and containment measures. Tail spines protect Bythotrephes against young of the year, but not larger fish, …


Spinal Locomotor Inputs To Individually Identified Reticulospinal Neurons In The Lamprey, James T. Buchanan Nov 2011

Spinal Locomotor Inputs To Individually Identified Reticulospinal Neurons In The Lamprey, James T. Buchanan

Biological Sciences Faculty Research and Publications

Locomotor feedback signals from the spinal cord to descending brain stem neurons were examined in the lamprey using the uniquely identifiable reticulospinal neurons, the Müller and Mauthner cells. The same identified reticulospinal neurons were recorded in several preparations, under reduced conditions, to address whether an identified reticulospinal neuron shows similar locomotor-related oscillation timing from animal to animal and whether these timing signals can differ significantly from other identified reticulospinal neurons. Intracellular recordings of membrane potential in identified neurons were made in an isolated brain stem-spinal cord preparation with a high-divalent cation solution on the brain stem to suppress indirect neural …


Investigating The Roles Of Ndj1 And Tid1 In Crossover Assurance In Saccharomyces Cerevisiae, Rianna Knowles Nov 2011

Investigating The Roles Of Ndj1 And Tid1 In Crossover Assurance In Saccharomyces Cerevisiae, Rianna Knowles

Master's Theses

Meiosis is the specialized process of cell division utilized during gametogenesis in all sexually reproducing eukaryotes, which consists of one round of DNA replication followed by two rounds of chromosome segregation and results in four haploid cells. Crossovers between homologous chromosomes promote proper alignment and segregation of chromosomes during meiosis.

Crossover interference is a genetic phenomenon in which crossovers are non-randomly placed along chromosomes. Crossover assurance ensures that every homologous chromosome pair obtains at least one crossover during Prophase I. Crossovers physically connect homologous pairs, allowing spindle fibers to attach and separate homologs properly. However, some organisms have shown an …


Loss-Of-Function Of Constitutive Expresser Of Pathogenesis Related Genes5 Affects Potassium Homeostasis In Arabidopsis Thaliana, Monica Borghi, Ana Rus, David E. Salt Oct 2011

Loss-Of-Function Of Constitutive Expresser Of Pathogenesis Related Genes5 Affects Potassium Homeostasis In Arabidopsis Thaliana, Monica Borghi, Ana Rus, David E. Salt

Biology Faculty Publications

Here, we demonstrate that the reduction in leaf K+ observed in a mutant previously identified in an ionomic screen of fast neutron mutagenized Arabidopsis thaliana is caused by a loss-of-function allele of CPR5, which we name cpr5-3. This observation establishes low leaf K+ as a new phenotype for loss-of-function alleles of CPR5. We investigate the factors affecting this low leaf K+ in cpr5 using double mutants defective in salicylic acid (SA) and jasmonic acid (JA) signalling, and by gene expression analysis of various channels and transporters. Reciprocal grafting between cpr5 and Col-0 was used to determine the relative importance of …


The Tubulin Deglutamylase Ccpp-1 Regulates The Function And Stability Of Sensory Cilia In C. Elegans, Robert O'Hagan, Brian P. Piasecki, Malan Silva, Prasad Phirke, Ken C Q Nguyen, David H. Hall, Peter Swoboda, Maureen M. Barr Oct 2011

The Tubulin Deglutamylase Ccpp-1 Regulates The Function And Stability Of Sensory Cilia In C. Elegans, Robert O'Hagan, Brian P. Piasecki, Malan Silva, Prasad Phirke, Ken C Q Nguyen, David H. Hall, Peter Swoboda, Maureen M. Barr

Department of Biology Faculty Scholarship and Creative Works

Background: Posttranslational modifications (PTMs) such as acetylation, detyrosination, and polyglutamylation have long been considered markers of stable microtubules and have recently been proposed to guide molecular motors to specific subcellular destinations. Microtubules can be deglutamylated by the cytosolic carboxypeptidase CCP1. Loss of CCP1 in mice causes cerebellar Purkinje cell degeneration. Cilia, which are conserved organelles that play important diverse roles in animal development and sensation, contain axonemes comprising microtubules that are especially prone to PTMs. Results: Here, we report that a CCP1 homolog, CCPP-1, regulates the ciliary localization of the kinesin-3 KLP-6 and the polycystin PKD-2 in male-specific sensory neurons …


The Group-Level Consequences Of Sexual Conflict In Multigroup Populations, Omar Tonsi Eldakar, Andrew C. Gallup Oct 2011

The Group-Level Consequences Of Sexual Conflict In Multigroup Populations, Omar Tonsi Eldakar, Andrew C. Gallup

Biology Faculty Articles

In typical sexual conflict scenarios, males best equipped to exploit females are favored locally over more prudent males, despite reducing female fitness. However, local advantage is not the only relevant form of selection. In multigroup populations, groups with less sexual conflict will contribute more offspring to the next generation than higher conflict groups, countering the local advantage of harmful males. Here, we varied male aggression within-and between-groups in a laboratory population of water striders and measured resulting differences in local population growth over a period of three weeks. The overall pool fitness (i.e., adults produced) of less aggressive pools exceeded …


Guantánamo Bodies: Law, Media, And Biopower, Cary H. Federman, Dave Holmes Oct 2011

Guantánamo Bodies: Law, Media, And Biopower, Cary H. Federman, Dave Holmes

Department of Justice Studies Faculty Scholarship and Creative Works

The idea of the Guantánamo detainee as a Muselmann, the lowest order of concentration camp inmates, contains within it important implications for the new understanding of sovereignty in the era of Guantánamo, in an age of exception. The purpose of this article is to explain the status of those who are detained at Guantánamo Bay. Stated broadly, in assessing that status, we will emphasize the connection between the altered meaning of sovereignty that has accompanied the placing of prisoners in an American penal colony in Cuba and the biopolitical status of the prisoners who reside there. More particularly, we …


Electrosensory Ampullary Organs Are Derived From Lateral Line Placodes In Bony Fishes, Melissa S. Modrell, William E. Benis, R. Glenn Northcutt, Marcus C. Davis, Clare V.H. Baker Oct 2011

Electrosensory Ampullary Organs Are Derived From Lateral Line Placodes In Bony Fishes, Melissa S. Modrell, William E. Benis, R. Glenn Northcutt, Marcus C. Davis, Clare V.H. Baker

Faculty Articles

Electroreception is an ancient subdivision of the lateral line sensory system, found in all major vertebrate groups (though lost in frogs, amniotes and most ray-finned fishes). Electroreception is mediated by 'hair cells' in ampullary organs, distributed in fields flanking lines of mechanosensory hair cell-containing neuromasts that detect local water movement. Neuromasts, and afferent neurons for both neuromasts and ampullary organs, develop from lateral line placodes. Although ampullary organs in the axolotl (a representative of the lobe-finned clade of bony fishes) are lateral line placode-derived, non-placodal origins have been proposed for electroreceptors in other taxa. Here we show morphological and molecular …


River Drying Lowers The Diversity And Alters The Composition Of An Assemblage Of Desert Riparian Arthropods, Kevin E. Mccluney, John L. Sabo Oct 2011

River Drying Lowers The Diversity And Alters The Composition Of An Assemblage Of Desert Riparian Arthropods, Kevin E. Mccluney, John L. Sabo

Biological Sciences Faculty Publications

Summary 1. Many studies have shown negative effects of river drying on in‐stream animals. However, the influence of river drying on riparian animals remains poorly studied. We examined ground‐dwelling riparian arthropod assemblages along a drying section of the semi‐arid San Pedro River in southeastern Arizona, U.S.A.

2. We found strong differences in assemblage composition, taxon diversity and the abundance of key taxa between dry and flowing sites, with higher diversity and abundance of most taxa at flowing sites.

3. Changes in assemblage composition, taxon diversity and abundance of representative taxa were associated with a combined measure of water availability that …


Accumulation Of Cadmium In Near-Isogenic Lines Of Durum Wheat (Triticum Turgidum L. Var Durum): The Role Of Transpiration, C. J. Quinn, A. Mohammad, Sheila M. Macfie Oct 2011

Accumulation Of Cadmium In Near-Isogenic Lines Of Durum Wheat (Triticum Turgidum L. Var Durum): The Role Of Transpiration, C. J. Quinn, A. Mohammad, Sheila M. Macfie

Biology Publications

Concentrations of cadmium in the grain of durum wheat (Triticum turgidum L. var durum) are often above the internationally acceptable limit of 0.2 mg kg−1. Cultivars that vary in concentrations of cadmium in the grain have been identified but the physiology behind differential accumulation has not been determined. Three pairs of near-isogenic lines (isolines) of durum wheat that vary in aboveground cadmium accumulation (8982-TL ‘high’ and ‘low’, W9260-BC ‘high’ and ‘low’, and W9261-BG ‘high’ and ‘low’) were used to test the hypothesis that the greater amounts of cadmium in shoots of the ‘high’ isolines are correlated with …


Novel Metabolic Attributes Of Cyanothece, A Group Of Unicellular Nitrogen Fixing Cyanobacteria., Anindita Bandyopadhyay, Thanura Elvitigala, Eric Welsh, Jana Stöckel, Michelle Liberton, Hongtao Min, Louis A. Sherman, Himadri B. Pakrasi Oct 2011

Novel Metabolic Attributes Of Cyanothece, A Group Of Unicellular Nitrogen Fixing Cyanobacteria., Anindita Bandyopadhyay, Thanura Elvitigala, Eric Welsh, Jana Stöckel, Michelle Liberton, Hongtao Min, Louis A. Sherman, Himadri B. Pakrasi

Department of Biological Sciences Faculty Publications

The genus Cyanothece comprises unicellular cyanobacteria that are morphologically diverse and ecologically versatile. Studies over the last decade have established members of this genus to be important components of the marine ecosystem, contributing significantly to the nitrogen and carbon cycle. System-level studies of Cyanothece sp. ATCC 51142, a prototypic member of this group, revealed many interesting metabolic attributes. To identify the metabolic traits that define this class of cyanobacteria, five additional Cyanothece strains were sequenced to completion. The presence of a large, contiguous nitrogenase gene cluster and the ability to carry out aerobic nitrogen fixation distinguishCyanothece as a genus …


Breeding Ecology Of The Pileated Woodpecker, Brandon Lennon Noel Oct 2011

Breeding Ecology Of The Pileated Woodpecker, Brandon Lennon Noel

Student Theses and Dissertations

The purported rediscovery of the ivory-billed woodpecker (Campephilus principalis) in the Cache River National Wildlife Refuge in 2004 was a monumental moment in conservation biology. Although controversy surrounds this and other sightings of ivory-billed woodpeckers within bottomland hardwood forests, the rediscovery of a species thought to have gone extinct revitalized optimism focused on its conservation. What knowledge we possess about ivory-billed woodpeckers comes from research done by James Tanner in the 1930s and his data are pseudo-replicated from just a few pairs. Tanner suggested that sweetgum-oak forest cover types were better quality habitats for ivory-billed woodpeckers and other woodpecker species …


Primary Literature Across The Undergraduate Curriculum: Teaching Science Process Skills And Content, Emily S.J. Rauschert, Joseph Dauer, Jennifer L. Momsen, Ariana Sutton-Grier Oct 2011

Primary Literature Across The Undergraduate Curriculum: Teaching Science Process Skills And Content, Emily S.J. Rauschert, Joseph Dauer, Jennifer L. Momsen, Ariana Sutton-Grier

Biological, Geological, and Environmental Faculty Publications

No abstract provided.


Lifelines Fall 2011, Southern Adventist University Oct 2011

Lifelines Fall 2011, Southern Adventist University

Lifelines - Biology Department Newsletter

The Fall 2011 issue of Lifelines features articles on biology student research, the pre-professional campout, and new professors Dr. Timothy Trott and Dr. Lucinda Hill.


2011 Meeting Missing Abstracts Oct 2011

2011 Meeting Missing Abstracts

Virginia Journal of Science

Abstracts not included in Virginia Journal of Science Volume 62, No. 1 and 2, presented at the 89th Annual Meeting of the Virginia Academy of Science, May 25-27, 2011, at the University of Richmond, Richmond VA.


Ribozyme Stability, Exon Skipping, And A Potential Role For Rna Helicase In Group I Intron Splicing By Coxiella Burnetii, Linda D. Hicks, Indu Warrier, Rahul Raghavan, Michael F. Minnick Oct 2011

Ribozyme Stability, Exon Skipping, And A Potential Role For Rna Helicase In Group I Intron Splicing By Coxiella Burnetii, Linda D. Hicks, Indu Warrier, Rahul Raghavan, Michael F. Minnick

Biological Sciences Faculty Publications

The 23S rRNA gene of Coxiella burnetii, the agent of Q fever in humans, contains an unusually high number of conserved, selfish genetic elements, including two group I introns, termed Cbu.L1917 (L1917) and Cbu.L1951 (L1951). To better understand the role that introns play in Coxiella's biology, we determined the intrinsic stability time periods (in vitro half-lives) of the encoded ribozymes to be similar to 15 days for L1917 and similar to 5 days for L1951, possibly due to differences in their sizes (551 and 1,559 bases, respectively), relative degrees of compactness of the respective RNA structures, and amounts of single-stranded …


The Roles Of Transcription And Genotoxins Underlying P53 Mutagenesis In Vivo, Barbara E. Wright, Karen H. Schmidt, Aaron T. Hunt, J Stephen Lodmell, Michael F. Minnick, Dennis K. Reschke Oct 2011

The Roles Of Transcription And Genotoxins Underlying P53 Mutagenesis In Vivo, Barbara E. Wright, Karen H. Schmidt, Aaron T. Hunt, J Stephen Lodmell, Michael F. Minnick, Dennis K. Reschke

Biological Sciences Faculty Publications

Transcription drives supercoiling which forms and stabilizes single-stranded (ss) DNA secondary structures with loops exposing G and C bases that are intrinsically mutable and vulnerable to non-enzymatic hydrolytic reactions. Since many studies in prokaryotes have shown direct correlations between the frequencies of transcription and mutation, we conducted in silico analyses using the computer program, mfg, which simulates transcription and predicts the location of known mutable bases in loops of high-stability secondary structures. Mfg analyses of the p53 tumor suppressor gene predicted the location of mutable bases and mutation frequencies correlated with the extent to which these mutable bases were exposed …


The Pleiotropic Effects Of Lc8 On The Anchoring Protein In Flagellar Radial Spoke Complex, Anjali Gupta Oct 2011

The Pleiotropic Effects Of Lc8 On The Anchoring Protein In Flagellar Radial Spoke Complex, Anjali Gupta

Dissertations (1934 -)

The goal of this thesis is to elucidate the assembly mechanism of macromolecular complexes in the microtubule-based axoneme in flagella. The axoneme is comprised of more than 400 distinct polypeptides. While all axonemal proteins are synthesized in the cell body, they need to be imported to the tip of the growing flagella for the final assembly. They are then assembled into distinctive structural complexes and integrated into precise positions relative to each other. The assembled macromolecular complexes operate in concert enabling the axoneme to beat rhythmically as a biological machine. This arduous process involves multiple reactions and meticulous regulation. However, …


Mechanisms Of Neuronal Death Induced By Environmental Toxicants In Murine Cortical Culture, Travis Rush Oct 2011

Mechanisms Of Neuronal Death Induced By Environmental Toxicants In Murine Cortical Culture, Travis Rush

Dissertations (1934 -)

This study was directed at examining the neurotoxic mechanisms of several classes of environmental toxicants implicated in neurodegenerative disease. Primary cortical cultures were exposed to organophosphorus pesticides, heavy metals and the cyanobacterial toxin, beta-N-methylamino-L-alanine (BMAA). Several components relating to neuronal injury were assessed in each study and novel aspects are described.

The main action of organophosphorous insecticides is generally believed to be the inhibition of acetylcholinesterase. However, these compounds are now recognized to inhibit many other enzymes and cause neuronal death through a variety of mechanisms. I found that exposure to chlorpyrifos or diazinon caused concentration-dependent neurotoxicity that could not …


Transcriptomic Characterization Of A Synergistic Genetic Interaction During Carpel Margin Meristem Development In Arabidopsis Thaliana, April N. Wynn, Elizabeth E. Rueschhoff, Robert G. Franks Oct 2011

Transcriptomic Characterization Of A Synergistic Genetic Interaction During Carpel Margin Meristem Development In Arabidopsis Thaliana, April N. Wynn, Elizabeth E. Rueschhoff, Robert G. Franks

Biological Sciences Research

In flowering plants the gynoecium is the female reproductive structure. In Arabidopsis thalianaovules initiate within the developing gynoecium from meristematic tissue located along the margins of the floral carpels. When fertilized the ovules will develop into seeds. SEUSS (SEU) and AINTEGUMENTA (ANT) encode transcriptional regulators that are critical for the proper formation of ovules from the carpel margin meristem (CMM). The synergistic loss of ovule initiation observed in the seu ant double mutant suggests that SEU and ANT share overlapping functions during CMM development. However the molecular mechanism underlying this synergistic interaction is unknown. Using …


Demasculinization And Feminization Of Male Gonads By Atrazine: Consistent Effects Across Vertebrate Classes, Krista A. Mccoy Oct 2011

Demasculinization And Feminization Of Male Gonads By Atrazine: Consistent Effects Across Vertebrate Classes, Krista A. Mccoy

Integrative Biology Faculty and Staff Publications

Atrazine is the most commonly detected pesticide contaminant of ground water, surface water, and precipitation. Atrazine is also an endocrine disruptor that, among other effects, alters male reproductive tissues when animals are exposed during development. Here, we apply the nine so-called “Hill criteria” (Strength, Consistency, Specificity, Temporality, Biological Gradient, Plausibility, Coherence, Experiment, and Analogy) for establishing cause–effect relationships to examine the evidence for atrazine as an endocrine disruptor that demasculinizes and feminizes the gonads of male vertebrates. We present experimental evidence that the effects of atrazine on male development are consistent across all vertebrate classes examined and we present a …


The Rice Miniature Inverted Repeat Transposable Element Mping Is An Effective Insertional Mutagen In Soybean, C. Nathan Hancock, Feng Zhang, Kristen Floyd, Aaron O. Richardson, Peter Lafayette, Donna Tucker, Susan R. Wessler, Wayne A. Parrott Oct 2011

The Rice Miniature Inverted Repeat Transposable Element Mping Is An Effective Insertional Mutagen In Soybean, C. Nathan Hancock, Feng Zhang, Kristen Floyd, Aaron O. Richardson, Peter Lafayette, Donna Tucker, Susan R. Wessler, Wayne A. Parrott

Faculty Publications

Insertional mutagenesis of legume genomes such as soybean (Glycine max) should aid in identifying genes responsible for key traits such as nitrogen fixation and seed quality. The relatively low throughput of soybean transformation necessitates the use of a transposon-tagging strategy where a single transformation event will produce many mutations over a number of generations. However, existing transposon-tagging tools being used in legumes are of limited utility because of restricted transposition (Ac/Ds: soybean) or the requirement for tissue culture activation (Tnt1: Medicago truncatula). A recently discovered transposable element from rice (Oryza …