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Full-Text Articles in Life Sciences

Polyq-Dependent Rna–Protein Assemblies Control Symmetry Breaking, Changhwan Lee, Patricia Occhipinti, Amy S. Gladfelter Jul 2015

Polyq-Dependent Rna–Protein Assemblies Control Symmetry Breaking, Changhwan Lee, Patricia Occhipinti, Amy S. Gladfelter

Dartmouth Scholarship

Dendritic growth in fungi and neurons requires that multiple axes of polarity are established and maintained within the same cytoplasm. We have discovered that transcripts encoding key polarity factors including a formin, Bni1, and a polarisome scaffold, Spa2, are nonrandomly clustered in the cytosol to initiate and maintain sites of polarized growth in the fungus Ashbya gossypii. This asymmetric distribution requires the mRNAs to interact with a polyQ-containing protein, Whi3, and a Pumilio protein with a low-complexity sequence, Puf2. Cells lacking Whi3 or Puf2 had severe defects in establishing new sites of polarity and failed to localize Bni1 protein. Interaction …


The Effects Of Hpa Axis Genetic Variation And Early Life Stress On Cortisol Levels In Preschool Age Children And On Amygdala And Hippocampus Volumes, Reactivity, And Connectivity At School Age, David Pagliaccio May 2015

The Effects Of Hpa Axis Genetic Variation And Early Life Stress On Cortisol Levels In Preschool Age Children And On Amygdala And Hippocampus Volumes, Reactivity, And Connectivity At School Age, David Pagliaccio

Arts & Sciences Electronic Theses and Dissertations

Internalizing psychopathology has been linked to increased cortisol reactivity and alterations in limbic brain structure and function, yet the mechanisms underlying these alterations are unclear. One key hypothesis is that stress plays a major causal role in these mechanisms. Animal studies find that chronic stress or glucocorticoid administration lead to alterations in hippocampal and amygdala structure and function. Relatedly, life stress is a major risk factors for depression while candidate gene studies have related variation in hypothalamic-pituitary-adrenal (HPA) axis genes to increased prevalence and severity of depression. The present work tested the hypothesis that genetic profile scores combining variance across …


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 …


Regulatory Paradigms For Modern Breeding, Drew L. Kershen, Wayne A. Parrott Apr 2015

Regulatory Paradigms For Modern Breeding, Drew L. Kershen, Wayne A. Parrott

Drew L. Kershen

Modern breeding, based upon molecular biology using genetic information, has made rapid advances. Breeders using rDNA techniques properly can think of this technique as traditional biotechnology. Within the past ten years, breeders have begun to use newer techniques [site-directed nuclease techniques (SDNs), RNAi, and synthetic biology] to create and to develop plants and animals with desired genetic traits. In this chapter printed in the NABC 26 Report (May 2015), the authors address the question: What is the appropriate regulatory paradigm for modern breeding?


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

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

Biology Faculty Articles

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 used ancient DNA extraction methods in well-preserved skeletal fragments from 20 individuals buried in Avondale Burial Place to investigate the origins of the …


An Approach For Determining And Measuring Network Hierarchy Applied To Comparing The Phosphorylome And The Regulome, Chao Cheng, Erik Andrews, Koon-Kiu Yan, Matthew Ung, Daifeng Wang, Mark Gerstein Mar 2015

An Approach For Determining And Measuring Network Hierarchy Applied To Comparing The Phosphorylome And The Regulome, Chao Cheng, Erik Andrews, Koon-Kiu Yan, Matthew Ung, Daifeng Wang, Mark Gerstein

Dartmouth Scholarship

Many biological networks naturally form a hierarchy with a preponderance of downward information flow. In this study, we define a score to quantify the degree of hierarchy in a network and develop a simulated-annealing algorithm to maximize the hierarchical score globally over a network. We apply our algorithm to determine the hierarchical structure of the phosphorylome in detail and investigate the correlation between its hierarchy and kinase properties. We also compare it to the regulatory network, finding that the phosphorylome is more hierarchical than the regulome.


A Bioinformatics Approach To Revealing The Genetic Basis For Host Range Specificity, Hayley A. Norian Feb 2015

A Bioinformatics Approach To Revealing The Genetic Basis For Host Range Specificity, Hayley A. Norian

James Madison Undergraduate Research Journal (JMURJ)

Bacteriophages, or phages, are viruses that infect bacteria. Mycobacteriophages are bacteriophages that specifically infect the genus Mycobacterium. This genus of bacteria includes human pathogens such as Mycobacterium tuberculosis, Mycobacterium leprae and Mycobacterium ulcerans, which cause tuberculosis, leprosy and Buruli ulcer, respectively. The full genome sequences of 654 mycobacteriophages are currently available. Collectively, these 654 phages encode 69,581 genes. Only 20.25% of these genes have at least one known homologue in NCBI, the National Center for Biotechnology Information, leaving roughly 80% of all known mycobacteriophage genes without even a predicted function. Bacteriophages are highly host-specific and typically only infect a small …


Genetic Structure And Demographic Analysis Of Key Deer (Odocoileus Virginianus Clavium), Vicki Villanova Jan 2015

Genetic Structure And Demographic Analysis Of Key Deer (Odocoileus Virginianus Clavium), Vicki Villanova

Electronic Theses and Dissertations

Recent improvements in genetic analyses have paved the way in using molecular data to answer questions regarding evolutionary history, genetic structure, and demography. Key deer are a federally endangered subspecies assumed to be genetically unique (based on one allozyme study), homogeneous, and have a female-biased population of approximately 900 deer. I used 985bp of the mitochondrial cytochrome b gene and 12 microsatellite loci to test two hypotheses: 1) if the Moser Channel is a barrier to gene flow, I should expect that Key deer are differentiated and have reduced diversity compared to mainland deer and (2) if isolation on islands …


Assessment Of A Metaviromic Dataset Generated From Nearshore Lake Michigan, Siobhan C. Watkins, Neil Kuehnle, C Anthony Ruggeri, Kema Malki, Katherine Bruder, Jinan Elayyan, Kristina Damisch, Naushin Vahora, Paul O'Malley, Brianne Ruggles-Sage, Zachary Romer, Catherine Putonti Jan 2015

Assessment Of A Metaviromic Dataset Generated From Nearshore Lake Michigan, Siobhan C. Watkins, Neil Kuehnle, C Anthony Ruggeri, Kema Malki, Katherine Bruder, Jinan Elayyan, Kristina Damisch, Naushin Vahora, Paul O'Malley, Brianne Ruggles-Sage, Zachary Romer, Catherine Putonti

Bioinformatics Faculty Publications

Bacteriophages are powerful ecosystem engineers. They drive bacterial mortality rates and genetic diversity, and affect microbially mediated biogeochemical processes on a global scale. This has been demonstrated in marine environments; however, phage communities have been less studied in freshwaters, despite representing a potentially more diverse environment. Lake Michigan is one of the largest bodies of freshwater on the planet, yet to date the diversity of its phages has yet to be examined. Here, we present a composite survey of viral ecology in the nearshore waters of Lake Michigan. Sequence analysis was performed using a web server previously used to analyse …


Polycystin-2 (Pkd2), Eccentric (Xnta), And Meckelin (Mks3) In The Ciliated Model Organism Paramecium Tetraurelia, Megan Smith Valentine Jan 2015

Polycystin-2 (Pkd2), Eccentric (Xnta), And Meckelin (Mks3) In The Ciliated Model Organism Paramecium Tetraurelia, Megan Smith Valentine

Graduate College Dissertations and Theses

Paramecium tetraurelia is a ciliated single cell used as a model organism for the study of ciliopathies. Ciliopathies are mammalian diseases involving the dysfunction of cilia, including cilia maintenance, construction, and signaling. P. tetraurelia and its cilia provides an excellent non-canonical system for the investigation and elucidation of proteins important for the structure, maintenance and function of cilia and ciliary beating. We utilize features of this cell such as its 1000's of cilia and highly organized and patterned cell surface to observe changes in swimming behavior or disruptions in the ordered cell surface which are not feasible in mammalian cells. …


High-Throughput Screening Of Age-Related Changes In Caenorhabditis Elegans, Neil Copes Jan 2015

High-Throughput Screening Of Age-Related Changes In Caenorhabditis Elegans, Neil Copes

USF Tampa Graduate Theses and Dissertations

This project was developed to identify novel methods for high-throughput culturing and screening of C. elegans to investigate age-related metabolic changes and to survey the proteomic and metabolomic factors associated with age-related changes. To accomplish these goals we developed a novel way to grow C. elegans in liquid culture in 96-well microplates for several weeks without suffering significant fluid loss due to evaporation and without needing to shake or unseal the plates for aeration. We also developed methods for assaying the total volume of live C. elegans in microplate cultures using a fluorescence microplate reader and for performing RNAi experiments …