Genetics and Genomics Commons^™

Endogenous Ros Levels In C. Elegans Under Exogenous Stress Support Revision Of Oxidative Stress Theory Of Life-History Tradeoffs, Samson W. Smith, Leigh C. Latta Iv, Dee R. Denver, Suzanne Estes

Biology Faculty Publications and Presentations

Background: The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals.

Results: Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with …

Hidden Diversity In Sardines: Genetic And Morphological Evidence For Cryptic Species In The Goldstripe Sardinella, Sardinella Gibbosa (Bleeker, 1849), Rey C. Thomas, Demian A. Willette, Kent E. Carpenter, Mudjekeewis D. Santos

Biological Sciences Faculty Publications

Cryptic species continue to be uncovered in many fish taxa, posing challenges for fisheries conservation and management. In Sardinella gibbosa, previous investigations revealed subtle intra-species variations, resulting in numerous synonyms and a controversial taxonomy for this sardine. Here, we tested for cryptic diversity within S. gibbosa using genetic data from two mitochondrial and one nuclear gene regions of 248 individuals of S. gibbosa, collected from eight locations across the Philippine archipelago. Deep genetic divergence and subsequent clustering was consistent across both mitochondrial and nuclear markers. Clade distribution is geographically limited: Clade 1 is widely distributed in the central Philippines, while …

Concordant Phylogenetic Patterns Inferred From Mitochondrial And Microsatellite Dna In The Giant Clam Tridacna Crocea, Timery S. Deboer, Ma Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toba, Paul H. Barber

Biological Sciences Faculty Publications

The boring giant clam, Tridacna crocea Lamarck, 1819, is a CITES-listed bivalve that is declining due to overharvest and environmental degradation. Previous molecular studies in the Coral Triangle using mitochondrial DNA indicated the presence of deep phylogenetic divergence and strong phylogeographic structure across this region, suggesting the possibility of multiple cryptic species. In the present study, we compare data from non-recombining mitochondrial (mtDNA; cytochrome oxidase subunit 1, COI) and eight microsatellite loci to better understand patterns of genetic structure and species boundaries in T. crocea populations across Indonesia and the Philippines. Microsatellite loci and mtDNA data from 618 individuals representing …

The Evolutionary Dynamics Of Transcription Factors, Operators, And Their Target Genes Across Prokaryotes, Marc Del Grande

Theses and Dissertations (Comprehensive)

In prokaryotes, transcriptional regulation commonly involves a transcription factor (TF) binding to a particular conserved sequence of nucleotides (operator). Binding elicits a transcriptional response, either activation or repression. The evolution of gene regulation has been identified as a primary driver of species diversity, making it an important area of research. This work examined the dynamics of the interactions between TFs and operators, and TFs and their primary target genes in attempt to assess the rapid evolution of transcriptional regulatory networks (TRNs) across a diverse set of prokaryotes. Using software packages, operator sequences from Escherichia coli K12 were compared to every …

The Role Of Body Size On The Outcome Of Mating Interactions In Drosophila Melanogaster, Adam C. Lounsbury

Theses and Dissertations (Comprehensive)

Sexual selection is the process by which some individuals produce more and/or better quality offspring than others because they are better at securing mates. While this may be accomplished by defeating same-sex rivals (intrasexual selection), individuals of one sex (typically females) may also “decide” on the suitability of individuals of the opposite sex (typically males), resulting in intersexual selection on attractive traits. While a great deal of scrutiny has focused on how sexual selection influences male display traits, much less scrutiny has been directed toward the factors underlying female preference, including genetic variation, as well as the extent to which …

Causes And Consequences Of Female Mate Choice In Drosophila Melanogaster: A Hemiclonal Analysis, Hannah Me Tennant

Theses and Dissertations (Comprehensive)

One of Darwin’s greatest questions, the reason why females prefer elaborate sexually selected male traits and displays, was elucidated by the Fisherian coevolution of male traits and female preferences. While variation in male attractiveness and ornamentation has received much attention, there has been little attempt to evaluate the causes and consequences of intraspecific variation in components of female preference. Furthermore, demonstrating a genetic basis to female preference does not answer the question of how within-population genetic variation is maintained.

Understanding the sources of variation in potential mating interactions between males and females is important because this variation determines the strength …

Multiplexing With Three-Primer Pcr For Rapid And Economical Microsatellite Validation, Salla Vartia, Patrick C. Collins, Thomas F. Cross, Richard D. Fitzgerald, David T. Gauthier, Philip Mcginnity, Luca Mirimin, Jens Carlsson

Biological Sciences Faculty Publications

The next generation sequencing revolution has enabled rapid discovery of genetic markers, however, development of fully functioning new markers still requires a long and costly process of marker validation. This study reports a rapid and economical approach for the validation and deployment of polymorphic microsatellite markers obtained from a 454 pyrosequencing library of Atlantic cod, Gadus morhua, Linnaeus 1758. Primers were designed from raw reads to amplify specific amplicon size ranges, allowing effective PCR multiplexing. Multiplexing was combined with a three-primer PCR approach using four universal tails to label amplicons with separate fluorochromes. A total of 192 primer pairs …

So, You Want To Use Next Generation Sequencing In Marine Systems? Insight From The Pan Pacific Advanced Studies Institute, D. A. Willette, F. W. Allendorf, P. H. Barber, D. J. Barshis, K. E. Carpenter, E. D. Crandall, W. A. Cresko, I. Fernandez-Silva, M. V. Matz, E. Meyer, M. D. Santos, L. W. Seeb, J. E. Seeb

Biological Sciences Faculty Publications

The emerging field of next-generation sequencing (NGS) is rapidly expanding capabilities for cutting edge genomic research, with applications that can help meet marine conservation challenges of food security, biodiversity loss, and climate change. Navigating the use of these tools, however, is complex at best. Furthermore, applications of marine genomic questions are limited in developing nations where both marine biodiversity and threats to marine biodiversity are most concentrated. This is particularly true in Southeast Asia. The first Pan-Pacific Advanced Studies Institute (PacASI) entitled "Genomic Applications to Marine Science and Resource Management in Southeast Asia" was held in July 2012 in Dumaguete, …

Fusarium Head Blight Resistance And Agronomic Performance In Soft Red Winter Wheat Populations, Daniela Sarti Dvorjak

Theses and Dissertations--Plant and Soil Sciences

Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schwein.(Petch)], is recognized as one of the most destructive diseases of wheat (Triticum aestivum L. and T. durum L.) and barley (Hordeum vulgare L.) worldwide. Breeding for FHB resistance must be accompanied by selection for desirable agronomic traits. Donor parents with two FHB resistance quantitative trait loci (QTL) Fhb1 (chromosome 3BS) and QFhs.nau-2DL (chromosome 2DL) were crossed to four adapted SRW wheat lines to generate backcross and forward cross progeny. F₂ individuals were genotyped and assigned to 4 different groups according to presence/ absence of …

Acquired Epigenetic And Chromosomal Changes In Women Treated For Breast Cancer, Noran Aboalela

Theses and Dissertations

Improved survival for women receiving chemotherapy for breast cancer (BC) has been accompanied by the development/persistence of psychoneurological symptoms (PNS) that compromise their quality of life. The biological basis for these PNS is unknown, but could reflect the acquisition of soma-wide chromosomal/epigenetic alterations. An important first step in testing this hypothesis is to determine if somatic genetic/epigenetic changes arise and persist following treatment. To answer this question we longitudinally studied 71 women (ages 23-71) with early-stage BC and collected measures before chemotherapy (baseline), and 4 weeks (mid-chemo); six months (during radiation therapy for a subset of women); and one year …

Methods For Integrative Analysis Of Genomic Data, Paul Manser

Theses and Dissertations

In recent years, the development of new genomic technologies has allowed for the investigation of many regulatory epigenetic marks besides expression levels, on a genome-wide scale. As the price for these technologies continues to decrease, study sizes will not only increase, but several different assays are beginning to be used for the same samples. It is therefore desirable to develop statistical methods to integrate multiple data types that can handle the increased computational burden of incorporating large data sets. Furthermore, it is important to develop sound quality control and normalization methods as technical errors can compound when integrating multiple genomic …

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 …

Recognition Of Two New Species Of Freshwater Crabs From The Seychelles Based On Molecular Evidence (Potamoidea: Potamonautidae)., Neil Cumberlidge, Savel Regan Daniels Phd

Journal Articles

The Afrotropical freshwater crab genus Seychellum is endemic to the granitic Seychelles in the Indian Ocean (Mahé, Silhouette, Praslin, La Digue and Frégate). Here we describe two new cryptic species of Seychellum that represent two evolutionarily separate lineages of a previously monotypic genus. This raises to three the number of species of freshwater crabs known from Seychelles. Each species is endemic to either one island (Silhouette) or to a pair of islands (Mahé and Frégate, or Praslin and La Digue). The three species can be clearly distinguished as separate lineages by DNA analysis, haplotyping and examination of gonopod characters. The …

Gene Electrotransfer Enhanced By Nanosecond Pulsed Electric Fields, Sigi Guo, Diane L. Jackson, Niculina I. Burcus, Yeong-Jer Chen, Shu Xiao, Richard Heller

Bioelectrics Publications

The impact of nanosecond pulsed electric fields (nsPEFs) on gene electrotransfer has not been clearly demonstrated in previous studies. This study was conducted to evaluate the influence of nsPEFs on the delivery of plasmids encoding luciferase or green fluorescent protein and subsequent expression in HACAT keratinocyte cells. Delivery was performed using millisecond electric pulses (msEPs) with or without nsPEFs. In contrast to reports in the literature, we discovered that gene expression was significantly increased up to 40-fold by applying nsPEFs to cells first followed by one msEP but not in the opposite order. We demonstrated that the effect of nsPEFs …

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

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 …

I Wish I Had Known This!: Impact Of Age On Life Choices And Testing Satisfaction For Brca1/2 Mutation Carriers Who Underwent Genetic Testing By Age 25, Sarah Elaine King

Theses and Dissertations

Objective: To examine if BRCA1/2 mutation carriers who received their positive genetic test result by age 25 were satisfied with their decision to undergo genetic testing and with the choices made regarding family planning, surveillance, and surgery. Methods: 72 participants recruited via social media completed a survey hosted by SurveyMonkey.com. Sixty-three met study criteria and were asked 40 quantitative and qualitative questions designed to assess family planning, surveillance, and surgery needs of young BRCA carriers, which included a six question Satisfaction with Decision Scale. Results: Regardless of age, participants were very satisfied with the decision to undergo genetic testing. Recommendations …

The Paternal Age Effect: A Preliminary Study Of Current Challenges For Prenatal Genetics Care, Andrew Tyler Gunter

Theses and Dissertations

Advanced paternal age (APA) is related to various genetic conditions, behavioral disorders, and adverse pregnancy outcomes. Since the publication of ACMG's practice guidelines on APA in 2008, much has been learned about the causes of paternal age effect (PAE) mutations and their clinical implications. However, no guidelines exist to refer these high-risk pregnancies to prenatal genetics care, nor are effective screening techniques presently available. As such, many patients are not fully-informed about the risks to their pregnancies due to possible APA effects, and neither are are the men who have fathered these pregnancies.

Our findings support that limited APA principles …

Walking The Edge With Controversial Use Of Preimplantation Genetic Diagnosis (Pgd): Opinions And Attitudes Of Genetic Counselors, Kristen Everton

Theses and Dissertations

Purpose: This study explored opinions and attitudes of genetic counselors regarding three controversial applications of preimplantation genetic diagnosis (PGD): PGD for early-onset Alzheimer, use of embryos that are BRCA positive after PGD revealed no disease-free embryos to be available, and PGD to select against a variant of unknown significance (VUS) for Marfan syndrome. Methods: Genetic counselors were contacted through the National Society of Genetic Counselors (NSGC) electronic mailing list. Inclusion criteria required that a participant was currently practicing as a genetic counselor, was a member of the NSGC, and has counseled patients about PGD. Twenty-nine participants volunteered to participate and …

The Impact Of Culture & Ethnicity On The Counseling Process: Perspectives Of Genetic Counselors From Minority Ethnic Groups, Brittanie Morris

Theses and Dissertations

In the genetic counseling profession, discussions about cross-cultural counseling and cultural competence emphasize the importance of patient culture as well as counselor culture in a counseling session. A culturally competent counselor should be aware of the influence of her own cultural values on interactions with patients and peers (Weil, 2000; & Uhlmann, Schuette, & Yashar, 2011). Focusing specifically on counselors from cultural/ethnic minorities, this mixed-methods study sought to empirically evaluate the influence of a counselor's cultural values and ethnic identity on the genetic counseling process. 162 genetic counselors, 58 of whom self-identified as being from an ethnic minority group, completed …

Lineage-Specific Transcriptional Profiles Of Symbiodinium Spp. Unaltered By Heat Stress In A Coral Host, Daniel J. Barshis, Jason T. Ladner, Thomas A. Oliver, Stephen R. Palumbi

Biological Sciences Faculty Publications

Dinoflagellates of the genus Symbiodinium form an endosymbiosis with reef building corals, in which photosynthetically derived nutrients comprise the majority of the coral energy budget. An extraordinary amount of functional and genetic diversity is contained within the coral-associated Symbiodinium, with some phylotypes (i.e., genotypic groupings), conferring enhanced stress tolerance to host corals. Recent advances in DNA sequencing technologies have enabled transcriptome-wide profiling of the stress response of the cnidarian coral host; however, a comprehensive understanding of the molecular response to stress of coral-associated Symbiodinium, as well as differences among physiologically susceptible and tolerant types, remains largely unexplored. Here, …

A Systems Biology Approach To Detect Eqtls Associated With Mirna And Mrna Co-Expression Networks In The Nucleus Accumbens Of Chronic Alcoholic Patients, Mohammed Mamdani

Theses and Dissertations

Alcohol Dependence (AD) is a chronic substance use disorder with moderate heritability (60%). Linkage and genome-wide association studies (GWAS) have implicated a number of loci; however, the molecular mechanisms underlying AD are unclear. Advances in systems biology allow genome-wide expression data to be integrated with genetic data to detect expression quantitative trait loci (eQTL), polymorphisms that regulate gene expression levels, influence phenotypes and are significantly enriched among validated genetic signals for many commonly studied traits including AD.

We integrated genome-wide mRNA and miRNA expression data with genotypic data from the nucleus accumbens (NAc), a major addiction-related brain region, of 36 …

Multi-Species Gene Networks And Drosophila Ethanol Sedation, Arnavaz Kollah

Theses and Dissertations

Alcohol use disorders (AUDs) are major health issues with few known genetic explanations. This project used the fruit fly (Drosophila melanogaster) model to identify genes and gene networks that influence alcohol intoxication, a phenotype related to alcohol abuse in humans. We used bioinformatic tools to build gene networks based on 24 published Drosophila ethanol-responsive genes with human orthologs. We then assessed the role of these networks in ethanol sedation by testing two of the networks seeded on IP3K2, a gene that regulates calcium signaling, and CG14630, a gene involved in carnitine biosynthesis. We knocked down several genes in each of …

Redefining Genomic Privacy: Trust And Empowerment, Yaniv Erlich, James B. Williams, David Glazer, Kenneth Yocum, Nita A. Farahany, Maynard Olson, Arvind Narayanan, Lincoln D. Stein, Jan A. Witkowski, Robert C. Kain

Faculty Scholarship

Fulfilling the promise of the genetic revolution requires the analysis of large datasets containing information from thousands to millions of participants. However, sharing human genomic data requires protecting subjects from potential harm. Current models rely on de-identification techniques in which privacy versus data utility becomes a zero-sum game. Instead, we propose the use of trust-enabling techniques to create a solution in which researchers and participants both win. To do so we introduce three principles that facilitate trust in genetic research and outline one possible framework built upon those principles. Our hope is that such trust-centric frameworks provide a sustainable solution …

Epistasis In Predator-Prey Relationships, Iuliia Inozemtseva

College of Graduate Studies: Theses & Dissertations

Epistasis is the interaction between two or more genes to control a single phenotype. We model epistasis of the prey in a two-locus two-allele problem in a basic predator- prey relationship. The resulting model allows us to examine both population sizes as well as genotypic and phenotypic frequencies. In the context of several numerical examples, we show that if epistasis results in an undesirable or desirable phenotype in the prey by making the particular genotype more or less susceptible to the predator or dangerous to the predator, elimination of undesirable phenotypes and then genotypes occurs.

Soil Microbial Community Distributions And Disease Suppressiveness In The Coastal Plain Of Georgia, Michael J. Sabula

College of Graduate Studies: Theses & Dissertations

This study compared the soil microbial communities of three vegetation types in the coastal plain of Georgia: 1. crop land actively in use for agricultural production, 2. transitional grassland in early stages of secondary succession, and 3. pristine unmanaged forest land. Microbial species diversity and quantities of microbial DNA were determined from each of these vegetation types at three separate locations near Statesboro, Georgia. Length heterogeneity PCR(LH-PCR) methods and subsequent analysis of fungal, bacterial, and metazoan communities by analysis of similarity (ANOSIM) revealed high within-group similarity by vegetation type, indicating land management intensity and vegetation cover is a strong determining …

The Prevalence And Effect Of Wolbachia Infection On The Brown Widow Spider (Latrodectus Geometricus), Brittany Dane' Arrington

College of Graduate Studies: Theses & Dissertations

Wolbachia was recently identified in the Brown Widow Spider (Latrodectus geometricus). This symbiont has not previously been found in this genus, therefore the consequences on the host’s population dynamics are unknown. The frequency of endosymbiont infection can provide insight into the population dynamics of the host as this bacteria is known to alter host life history. In my 1^st chapter I determine the prevalence of Wolbachia pipentis infection in in the Brown Widow Spider (Latrodectus geometricus) from five locations in the Southeastern United States. Infection frequency differed significantly among sampling locations, ranging from 20% to …

Understanding Crx-Associated Retinopathies Using Animal Models, Nicholas Minh Abell Tran

All Theses and Dissertations (ETDs)

Cone-rod homeobox: CRX) protein is a "paired-like" homeodomain transcription factor that is essential for regulating rod and cone photoreceptor transcription. Mutations in human CRX are associated with the dominant retinopathies Retinitis Pigmentosa: RP), Cone-Rod Dystrophy: CoRD) and Leber Congenital Amaurosis: LCA), with variable severity. The goal of my dissertation project was to develop and characterize animal models to understand genetic mechanisms of phenotypic diversity in CRX-associated disease. Heterozygous Crx Knock-Out: KO) mice: "+/-") have normal vision as adults and fail to model the dominant human disease.

We generated two Crx Knock-IN: K-IN) mouse models: CrxE168d2: "E168d2") and CrxR90W: "R90W"), which …

Beef Cattle Body Temperature During Climatic Stress: A Genome-Wide Association Study, Jeremy T. Howard, Stephen D. Kachman, Warren M. Snelling, E. John Pollak, Daniel C. Ciobanu, Larry A. Kuehn, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Cattle are reared in diverse environments and collecting phenotypic body temperature (BT) measurements to characterize BT variation across diverse environments is difficult and expensive. To better understand the genetic basis of BT regulation, a genome-wide association study was conducted utilizing crossbred steers and heifers totaling 239 animals of unknown pedigree and breed fraction. During predicted extreme heat and cold stress events, hourly tympanic and vaginal BT devices were placed in steers and heifers, respect i v e l y. I n d i v i dua l s we r e genotyped with t h e BovineSNP50K_v2 assay and data …

The Diversity Of Quantitative Trait Loci In Yeast Sporulation Efficiency, Kimberly Lorenz

All Theses and Dissertations (ETDs)

A complex trait is one that exhibits continuous phenotypic variation due to genetic variation in many quantitative trait genes: QTGs). The ultimate goal of genetics is to relate genotype to phenotype; in the case of complex traits this requires a better understanding of what types of genes harbor causal natural variation, and what form the variation takes. Here I describe two experiments using the model complex trait of sporulation efficiency in the yeast Saccharomyces cerevisiae, one to specifically investigate how small effects contribute to a quantitative trait and the other to determine whether certain types of genes are more likely …