Genetics and Genomics Commons^™

Genetic Analysis Of Serf Gene Function In Drosophila Melanogaster And Its Contribution To A Fly Model Of Spinal Muscular Atrophy, Swagata Ghosh

Theses and Dissertations--Biology

The Serf gene is evolutionarily highly conserved but its biological function is not known in any organism. In human, SERF1/H4F5 was first identified as a modifier of the disease Spinal Muscular Atrophy (SMA). SMA is caused by mutations in the Survival Motor Neuron 1(SMN1) gene leading to diminished levels of the Smn protein. More than 90% of patients with the most severe form of SMA have deletions that remove SERF1 as well as mutaions within SMN1. Hence, loss of Serf activity is hypothesized to exacerbate SMA disease progression. The primary motivation of this thesis was to test …

¬Multilocus Phylogeny Of The Lichen Family Megasporaceae, Tim B. Wheeler

Graduate Student Theses, Dissertations, & Professional Papers

The lichen symbiosis is one of the oldest studied mutualisms; in fact, Frank and De Bary coined the term "symbiosis" while studying lichens (Frank, 1877; De Bary 1879). The widespread, stable association between the mycobiont and photobiont in lichens offers an ideal system for the study of co-evolution. The recent application of molecular data to lichens has begun to unveil the complexities involved in these associations (Upreti et al. 2015, Spribille et al. 2016). Lichenized fungi make up a huge fraction of fungal diversity (Nash 2008), yet very little is known of their genetic diversity. Fungal taxonomy is notoriously difficult …

Increased Insertion Number Leads To Increased Sperm Transfer And Fertilization Success In A Nursery Web Spider, Alissa G. Anderson, Eileen Hebets

Eileen Hebets Publications

Across animals, a male's fitness is largely dictated by his ability to fertilize eggs; and there exists a plethora of male adaptations associated with increasing fertilization success. In the nursery web spider, Pisaurina mira, males restrain females prior to and during copulation by wrapping them with silk. Previous research demonstrates that copulatory silk wrapping reduces a male's chance of being sexually cannibalized and increases the number of sperm transfer opportunities (termed insertions) that a male can achieve within a mating. While avoiding cannibalism provides an obvious survival benefit to males, the impact of insertion number on male fitness remains …

Dna Metabarcoding Reveals Provisioning Of Pollution-Sensitive Aquatic Insects, Resource Partitioning, And Dietary Shifts Among Breeding Neotropical Migratory Songbirds In A Riparian Habitat, Brian K. Trevelline

Electronic Theses and Dissertations

Elucidating the diet of Neotropical migratory birds is essential to our understanding of their ecology and to their long-term conservation. Beyond broad taxonomic or morphological categories, however, the diet of Neotropical migrants is poorly documented. Using the molecular techniques of DNA barcoding and next-generation sequencing, we elucidated the diet of Neotropical migratory songbirds breeding in the riparian zones of headwater Appalachian streams. This approach resulted in a genus- or species-level description of diets that improved the current understanding of how songbirds utilize aquatic prey resources in riparian habitats. Furthermore, our approach revealed that breeding songbirds partition prey resources within a …

Determining The Reproductive Patterns Of The Titan Acorn Barnacle (Megabalanus Coccopoma) In Its Introduced Range, Isabel L. Moran Ms.

Honors College Theses

Invasive species are a significant conservation concern given their contribution to native species decline. The barnacle, Megabalanus coccopoma, is a common invasive species in tropical and subtropical regions of both the Pacific and Atlantic oceans. Little is known about the life history and ecology of M. coccopoma, and data on reproductive biology could provide valuable insight into its propensity to establish introduced populations. Most species of barnacle (including M. coccopoma) are hermaphroditic, but self-fertilization is rare in species studied to date. A recent genetic study of introduced M. coccopoma populations in the southeastern US showed high levels of …

Characterization Of A Large Vertebrate Genome And Homomorphic Sex Chromosomes In The Axolotl, Ambystoma Mexicanum, Melissa Keinath

Theses and Dissertations--Biology

Changes in the structure, content and morphology of chromosomes accumulate over evolutionary time and contribute to cell, developmental and organismal biology. The axolotl (Ambystoma mexicanum) is an important model for studying these changes because: 1) it provides important phylogenetic perspective for reconstructing the evolution of vertebrate genomes and amphibian karyotypes, 2) its genome has evolved to a large size (~10X larger than human) but has maintained gene orders, and 3) it possesses potentially young sex chromosomes that have not undergone extensive differentiation in the structure that is typical of many other vertebrate sex chromosomes (e.g. mammalian XY chromosomes …

Uncovering Candidate Cold Tolerance Genes In Maize (Zea Mays), Raeann N. Goering

Departmental Honors Projects

With booming populations soon to overwhelm the world's food production capabilities, studying what makes crop organisms, like maize, efficient is crucial to ensure that the demand for food is met. Planting earlier in the spring would lengthen the crop season and produce larger yields provided the crop is tolerant to early spring’s low temperatures. Plants can adjust to abiotic stresses through biochemical changes controlled by transcription of genes. Trained plants can be produced by pre-exposing them to a lesser stress, allowing them to recover, then exposing them to a greater, longer stress. It is hypothesized that trained plants will tolerate …

An Undergraduate Cell Biology Lab: Western Blotting To Detect Proteins From Drosophila Eye, Neha Gogia, Ankita Sarkar, Amit Singh

Biology Faculty Publications

We have developed an undergraduate laboratory to allow detection and localization of proteins in the compound eye of Drosophila melanogaster, a.k.a fruit fly. This lab was a part of the undergraduate curriculum of the cell biology laboratory course aimed to demonstrate the use of Western Blotting technique to study protein localization in the adult eye of Drosophila. Western blotting, a two-day laboratory exercise, can be used to detect the presence of proteins of interests from total protein isolated from a tissue. The first day involves isolation of proteins from the tissue and SDS-PAGE (sodium dodecyl sulfate-polyacrylamide) gel …

Real-Time Quantitative Pcr To Demonstrate Gene Expression In An Undergraduate Lab, Abijeet Singh Mehta, Amit Singh

Biology Faculty Publications

The objective of this teaching note is to develop a laboratory exercise, which allows students to get a hands-on experience of a molecular biology technique to analyze gene expression. The short duration of the biology laboratory for an undergraduate curriculum is the biggest challenge with the development of new labs. An important part of cell biology or molecular biology undergraduate curriculum is to study gene expression. There are many labs to study gene expression in qualitative manner. The commonly used reporter gene expression studies are primarily qualitative. However, there is no hands-on experience exercise to quantitatively determine gene expression. Therefore, …

Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr

College of Graduate Studies: Theses & Dissertations

Color polymorphism in aposematic mimicry systems is a perplexing phenomenon for evolutionary biologists, as theoretically the benefits of converging on a model phenotype should constrain the evolution of phenotypic diversity in these systems (i.e., color polymorphism should not occur). Nevertheless, color polymorphism in mimicry systems is prevalent throughout many taxa. In some of these systems, the evolution of color polymorphism results in the existence of non-mimetic morphs, such as those that are cryptic. The case of ground snakes (Sonora semiannulata) is unique in that color polymorphism encompasses both mimetic and cryptic morphs, as well as individual mimetic and …

Investigating Mirna Functions In Arabidopsis By Short Tandem Target Mimic (Sttm), Yiyou Gu

Dissertations, Master's Theses and Master's Reports

MicroRNA (miRNAs) and other endogenous small RNAs play important role in regulating gene expression in eukaryotes. Till now, several techniques have been developed for miRNA function analysis. Because of the characteristic of miRNAs, the most applicable method for miRNA function research is blocking the whole miRNA family specifically. Here, we report an artificial non-coding transcript termed Short Tandem Target Mimic (STTM) for blocking miRNA activity in Arabidopsis thaliana. The STTM composed of two miRNA target sites with three nucleotides bulge in the miRNA cleavage site, the two-miRNA targets separated by spacer linker. We used this technique blocking several important endogenous …

Responding To Soil Fungal Communities: A Look At Interactions Between Arbuscular Mycorrhizal Fungi And The Common Yellow Monkeyflower, Mariah Mcintosh

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The obligate fungal mutualists arbuscular mycorrhizal fungi (AMF) colonize the roots approximately 80% of vascular plants, generally thought to provide mineral nutrition, pathogen protection, or drought resistance to plants in exchange for photosynthetic carbon. Because of the ecological and evolutionary significance of these interactions, much work has been done to understand this symbiosis at the community level. However, much remains to be understood about how AMF affect plant fitness on an individual level. In this study, we took advantage of the tractability of the emerging model species Mimulus guttatus, the common yellow monkeyflower, to identify genetic differences in how …

Mitochondrial And Nuclear Patterns Of Conflict And Concordance At The Gene, Genome, And Behavioral Scales In Desmognathus Salamanders, Justin D. Kratovil

Theses and Dissertations--Biology

Advancements in molecular sequencing have revealed unexpected cryptic genetic diversity and contrasting evolutionary histories within genes and between genomes of many organisms; often in disagreement with recognized taxonomy. Incongruent patterns between the mitochondrial and nuclear evolutionary history can have several plausible explanations, but widespread systematic conflict inevitably challenges our conceptions of species boundaries when there is discordance between coevolving and coinherited genomes. It is unknown to what degree mitonuclear conflict drives the process of divergence, or how ubiquitous these patterns are across the tree of life. To understand the evolutionary relevance of intergenomic discordance we must identify the conflicting patterns …

Importance Of The Antenniform Legs, But Not Vision, For Homing By The Neotropical Whip Spider Paraphrynus Laevifrons, Verner P. Bingman, Jacob M. Graving, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Amblypygids, or whip spiders, are nocturnal, predatory arthropods that display a robust ability to navigate to their home refuge. Prior field observations and displacement studies in amblypygids demonstrated an ability to home from distances as far away as 10 m. In the current study, micro-transmitters were used to take morning position fixes of individual Paraphrynus laevifrons following an experimental displacement of 10 m from their home refuge. The intention was to assess the relative importance of vision compared with sensory input acquired from the antenniform legs for navigation as well as other aspects of their spatial behavior. Displaced individuals were …

Protective Effect Of Anti-Phosphatidylserine Antibody In A Guinea Pig Model Of Advanced Hemorrhagic Arenavirus Infection, John M. Thomas, Philip E. Thorpe

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Objective: Host derived markers on virally infected cells or virions may provide targets for the generation of antiviral agents. Recently, we identified phosphatidylserine (PS) as a host marker of virions and virally-infected cells.

Methods and Materials: Under normal physiological conditions, PS is maintained on the inner leaflet of the plasma membrane facing the cytosol. Following viral infection, activation or pre-apoptotic changes cause PS to become externalized. We have previously shown that bavituximab, a chimeric human-mouse antibody that binds PS complexed with β2-glycoprotein I (β2GP1), protected rodents against lethal Pichinde virus and cytomegalovirus infections.

Results: Here, we determined the antiviral activity …

Evolution Of Antagonistic Relationships In Proteins: A Case Study Of Radialis- And Diviricata-Like Genes, Ao Gao

Theses and Dissertations

The antagonistic relationship of proteins describes the opponent interactions that result in one protein suppressing the function of another. Developmental genetic studies of Antirrhinum majus demonstrated that two transcription factors from the MYB gene family, RAD and DIV, interact through antagonism to regulate floral dorsoventral asymmetry. Interestingly, similar antagonistic interactions were found among proteins of FSM1 (RAD-like), MYBI (DIV-like), and DRIF in Solanum lycopersicum, which is involved in fruit development. Here, we report on the homology of these antagonistic MYB proteins based on reconstruction of the phylogeny of I-box-like and R-R-type clades, where RAD- and DIV-like belong, …

Cullin-4 Regulates Wingless And Jnk Signaling-Mediated Cell Death In The Drosophila Eye., Meghana Tare, Ankita Sarkar, Shimpi Bedi, Madhuri Kango-Singh, Amit Singh

Biology Faculty Publications

In all multicellular organisms, the fundamental processes of cell proliferation and cell death are crucial for growth regulation during organogenesis. Strict regulation of cell death is important to maintain tissue homeostasis by affecting processes like regulation of cell number, and elimination of unwanted/unfit cells. The developing Drosophila eye is a versatile model to study patterning and growth, where complex signaling pathways regulate growth and cell survival. However, the molecular mechanisms underlying regulation of these processes is not fully understood. In a gain-of-function screen, we found that misexpression of cullin-4 (cul-4), an ubiquitin ligase, can rescue reduced eye mutant phenotypes. Previously, …

Comparative Genomic Analysis Of Two Serotype 1/2b Listeria Monocytogenes Isolates From Analogous Environmental Niches Demonstrates The Influence Of Hypervariable Hotspots In Defining Pathogenesis, Aidan Casey, Kieran Jordan, Aidan Coffey, Edward M. Fox, Olivia Mcauliffe

Department of Biological Sciences Publications

The vast majority of clinical human listeriosis cases are caused by serotype 1/2a, 1/2b, 1/2c, and 4b isolates of Listeria monocytogenes. The ability of L. monocytogenes to establish a systemic listeriosis infection within a host organism relies on a combination of genes that are involved in cell recognition, internalization, evasion of host defenses, and in vitro survival and growth. Recently, whole genome sequencing and comparative genomic analysis have proven to be powerful tools for the identification of these virulence-associated genes in L. monocytogenes. In this study, two serotype 1/2b strains of L. monocytogenes with analogous isolation sources, but …

A Microbiomic Approach To The Characterization Of The Impacts And Influences Of Viral, Bacterial, And Harmful Algal Bloom Toxins On The Bottlenose Dolphin, Corey David Russo

Dissertations

As apex predators that display high site fidelity Tursiops truncatus (bottlenose dolphin) are indicators of marine ecosystem health. Bottlenose dolphins, additionally, display pathogenesis and immune response similar to that of humans. Humans and coastal bottlenose dolphins, in particular, are constantly exposed to the same industrial, agricultural and domestic toxins and pathogens, contaminants and pollutants. Thus, studies on the bottlenose dolphin are also valuable in bridging the gap between ocean and human health. Bottlenose dolphins are susceptible to viral bacterial and toxin infection. Infection in the bottlenose dolphin manifests itself in the form of mass stranding events, unusual mortality events, chronic …

Examination Of The Relevance Of Pi3k And Pten Pathway In Ustilago Maydis., Nathaniel Edward Dalton

Electronic Theses and Dissertations

Ustilago maydis is a fungal pathogen that is an obligate parasite on Zea mays (Corn) in order to undergo and complete its sexual life cycle. The cells grow as a haploid form until they meet a compatible partner and undergo a dimorphic switch from a budding yeast-like cell type to a filamentous dikaryon. Infection of the host plant is characterized by leaf chlorosis, anthocyanin content, and formation of large galls that develop on the stem, leaves, cobs, and flowers. Many signaling cascades such as MAPK and PKA are involved in the regulation of the infection lifecycle. The Phosphatidylinosotiol 3 Kinase/ …

Identification And Characterization Of Genes Involved In Metabolism Of N5 Monoene Precursors To N5 Anacardic Acids In The Trichomes Of Pelargonium X Hortorum., Richa A. Singhal

Electronic Theses and Dissertations

Unusual monoenoic fatty acids (UMFA’s) and specialized metabolites called anacardic acids (AnAc) are produced in glandular trichomes of Pelargonium ´ hortorum (geranium). The UMFA’s, 16:1^∆11 and 18:1^∆13 are precursors for the synthesis of unsaturated AnAc 22:1n5and 24:1n5 that contribute to pest resistance in geraniums. UMFAs and their derived AnAc metabolites not only provide a useful biological marker that differentiates the biosynthetic pathway for unusual mononenes from the common fatty acids (i.e. stearic, palmitic, oleic, linoleic and linolenic) but also have industrial, medical and agricultural applications. Fatty acid biosynthesis enzymes like acyl carrier proteins (ACPs); thioesterases (TEs) and β-ketoacyl-ACP …

Minority Middle And High School Students' Interest In Science: An Exploration Of Teachers' Perceptions, Caroline Makere

Dissertations

A high school teacher conducted a study about minority middle and high school students’ interest in science. The problem was to find out why African American and Hispanic students were showing very little interest in science. The researcher used four middle school science teachers and nine high school science teachers, all from inner city schools in a big city of the Midwest United States except for one middle school teacher from a nearby suburb. The participants answered a survey questionnaire followed with a face-to-face recorded interview. The findings of the study confirmed that students showed little interest in science due …

Discrete Mutations In Colorectal Cancer Correlate With Defined Microbial Communities In The Tumor Microenvironment, Michael B. Burns, Emmanuel Montassier, Juan Abrahante, Timothy K. Starr, Dan Knights, Ran Blekhman

Biology: Faculty Publications and Other Works

Variation in the gut microbiome has been linked to colorectal cancer (CRC), as well as to host genetics. However, we do not know whether genetic mutations in CRC tumors interact with the structure and composition of the microbial communities surrounding the tumors, and if so, whether changes in the microbiome can be used as a predictor for tumor mutational status. Here, we characterized the association between CRC tumor mutational landscape and its proximal microbial communities by performing whole exome sequencing and microbiome profiling in tumors and normal colorectal tissue samples from the same patient. We find a significant association between …

Design Of Novel Ion Channel Modulators, Vladimir Yarov-Yarovoy

Science Seminar Series

Function and modulation of neuronal sodium channels are critical for the neuromodulation of electrical excitability and synaptic transmission in neurons - the basis for many aspects of signal transduction, learning, memory and physiological regulation. Mutations in neuronal voltage-gated sodium channel genes are responsible for various human neurological disorders. Furthermore, human neuronal voltage-gated sodium channels are primary targets of therapeutic drugs used as local anesthetics and for treatment of neurological and cardiac disorders. Yarov-Yarovoy's lab is working on rational design of novel therapeutically useful blockers of voltage-gated sodium channels for treatment of pain and epilepsy. Serious, chronic pain affects at least …

A New Timepiece: An Epigenetic Mitotic Clock, Brock C. Christensen, Karl T. Kelsey

Dartmouth Scholarship

A new mitotic clock and mathematical approach that incorporates DNA methylation biology common among human cell types provides a new tool for cancer epigenetics research.

Rna-Seq Of Borrelia Burgdorferi In Multiple Phases Of Growth Reveals Insights Into The Dynamics Of Gene Expression, Transcriptome Architecture, And Noncoding Rnas, William K. Arnold, Christina R. Savage, Catherine A. Brissette, Janakiram Seshu, Jonathan Livny, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Borrelia burgdorferi, the agent of Lyme disease, differentially expresses numerous genes and proteins as it cycles between mammalian hosts and tick vectors. Insights on regulatory mechanisms have been provided by earlier studies that examined B. burgdorferi gene expression patterns during cultivation. However, prior studies examined bacteria at only a single time point of cultivation, providing only a snapshot of what is likely a dynamic transcriptional program driving B. burgdorferi adaptations to changes during culture growth phases. To address that concern, we performed RNA sequencing (RNA-Seq) analysis of B. burgdorferi cultures at early-exponential, mid-exponential, and early-stationary phases …

Promises And Challenges Of Eco-Physiological Genomics In The Field: Tests Of Drought Responses In Switchgrass. Plant Physiology, John T. Lovell, Eugene V. Shakirov, Scott Schwartz, David B. Lowry, Michael J. Aspinwall, Samuel H. Taylor, Jason Bonnette, Juan Diego Palacio-Mejia, Christine V. Hawkes, Philip A. Fay, Thomas E. Juenger

Biological Sciences Faculty Research

Identifying the physiological and genetic basis of stress tolerance in plants has proven to be critical to understanding adaptation in both agricultural and natural systems. However, many discoveries were initially made in the controlled conditions of greenhouses or laboratories, not in the field. To test the comparability of drought responses across field and greenhouse environments, we undertook three independent experiments using the switchgrass reference genotype Alamo AP13. We analyzed physiological and gene expression variation across four locations, two sampling times, and three years. Relatively similar physiological responses and expression coefficients of variation across experiments masked highly dissimilar gene expression responses …

Evolutionary Interpretations Of Mycobacteriophage Biodiversity And Host-Range Through The Analysis Of Codon Usage Bias, Laura A. Esposito, Swati Gupta, Fraida Streiter, Ashley Prasad, John J. Dennehy

Publications and Research

In an genomics course sponsored by the Howard Hughes Medical Institute (HHMI), undergraduate students have isolated and sequenced the genomes of more than 1,150 mycobacteriophages, creating the largest database of sequenced bacteriophages able to infect a single host, Mycobacterium smegmatis, a soil bacterium. Genomic analysis indicates that these mycobacteriophages can be grouped into 26 clusters based on genetic similarity. These clusters span a continuum of genetic diversity, with extensive genomic mosaicism among phages in different clusters. However, little is known regarding the primary hosts of these mycobacteriophages in their natural habitats, nor of their broader host ranges. As such, it …

Comparative Population Genomics And Speciation Of Snakes Across The North American Deserts, Edward A. Myers

Dissertations, Theses, and Capstone Projects

Understanding the process of speciation is of central interest to evolutionary biologists. Speciation can be studied using a phylogeographic approach, by identifying regions that promote lineage divergence, addressing whether speciation has occurred with gene flow, and when extended to multiple taxa, addressing if the same patterns of speciation are shared across codistributed groups with different ecologies. Here I examine the comparative phylogeographic histories and population genomics of thirteen snake taxa that are widely distributed and co-occur across the arid southwest of North America. I first quantify the degree to which these species groups have a shared history of population divergence …

The Regulation Of The Phosphatidate Phosphatase Gene Pah1 And Its Regulatory Role On Cell Homeostasis, Goldie Libby Sherr

Dissertations, Theses, and Capstone Projects

The Saccharomyces cerevisiae gene, PAH1, encodes a phosphatidate (PA) phosphatase that plays a fundamental role in lipid metabolism. PA phosphatases are key enzymes that catalyze the PA dephosphorylation reaction to form diacylglycerides, the first step in the synthesis of triacylglycerols. Pah1p, one of the main PA phosphatases in yeast, has not only emerged as a key player in lipid biosynthetic pathways, but also acts as an important regulator of nuclear membrane biogenesis, the transcriptional regulation of many inositol-sensitive upstream activating sequence (UAS_INO)containing genes needed for phospholipid synthesis, vacuole homeostasis, and lipid droplet formation. Due to its …