Genetics Commons^™

Functional Analyses Of The Polycomb-Group Genes In Sea Lamprey Embryos Undergoing Programmed Dna Loss, Cody Saraceno

Theses and Dissertations--Biology

During early embryonic development, the sea lamprey (Petromyzon marinus) undergoes programmatic elimination of DNA from somatic progenitor cells in a process termed programmed genome rearrangement (PGR). Eliminated DNA eventually becomes condensed into micronuclei, which are then physically degraded and permanently lost from the cell. Previous studies indicated that many of the genes eliminated during PGR have mammalian homologs that are bound by polycomb repressive complex (PRC) in embryonic stem cells. To test whether PRC components play a role in the faithful elimination of germline-specific sequences, we used a combination of CRISPR/Cas9 and lightsheet microscopy to investigate the impact …

Caenorhabditis Elegans Rapgef Promotes Synaptic Development Through A Small G Protein Signaling Cascade, Reagan Em Lamb

Theses and Dissertations--Neuroscience

Synaptic dysfunction is a major contributor toward the development of many neurological disorders. For proper development, synapses require a series of signaling pathways to guide them, but not all the mechanisms underlying these processes are understood. Here, we used the neuromuscular junction of Caenorhabditis elegans as a model circuitry for examining underlying pathways that mediate proper development of synapses. We hypothesized that the C. elegans RapGEF2 and RapGEF6 orthologue, PXF-1, contributed toward development of cholinergic synapses at the neuromuscular junction. Using behavioral assays and fluorescence microscopy, we found that pxf-1 mutant animals had decreased neuromuscular junction function and decreased synaptic …

Determining Population Structure In Kentucky Parascaris Univalens Specimens, Constance Finnerty

Theses and Dissertations--Veterinary Science

Parascaris univalens is a highly pathogenic nematode that affects the gastrointestinal system of young horses. When unaddressed, this parasite causes severe intestinal impactions and even death. Parascaris univalens is also found to have an emergence of anthelmintic resistances, causing a concern for horse owners. Despite its clinical significance, very little work has been done on Parascaris univalens to identify its population structure. This study aimed to determine the population structure of Parascaris univalens through Illumina next generation sequencing (NGS) on three hierarchical categorizations: within a horse, within an isolated herd, and within horses in the state of Kentucky. A total …

Genomic Studies Of The Equine Bloodworm, Strongylus Vulgaris, Nichol Ripley

Theses and Dissertations--Veterinary Science

Strongylus vulgaris is the most pathogenic nematode parasite of grazing horses worldwide. This gastrointestinal parasitic nematode is in the family Strongylidae under the subfamily Strongylinae, or Strongylins. While the epidemiology, complete life cycle, and high pathogenicity of the fourth and fifth larval stages of S. vulgaris are well established, we understand very little about its biology. This parasite is renowned for its unique life cycle and capacity to cause arterial damage, leading to significant health and economic impacts for the equine industry. It also is the most intensively documented Strongylin; however, S. vulgaris has yet to gain drug resistance as …

Exploring 3d Genome Interaction And Epigenetic Regulation Via Swi/Snf Complex And Deep Learning Models, Ruoyun Wang

Dartmouth College Ph.D Dissertations

The three-dimensional organization of the genome is fundamental in regulating gene expression and maintaining cellular function. This organization's complexities, influenced by epigenetic marks and chromatin remodeling complexes, are crucial for understanding genomic regulation. Among these, the SWI/SNF complexes are key, facilitating chromatin accessibility and regulating gene activity across cell types. The first part of my dissertation focuses on SWI/SNF complexes, exploring their role in chromatin remodeling and their impact on 3D genome architecture. Utilizing next-generation sequencing (NGS) techniques, this section investigates the interplay between these complexes and chromatin structure. During my research on the SWI/SNF complex, I was intrigued by …

Contribution Of The Transcription Factor Red Nac To Low Nitrogen Phenotypes In Poplar, Shane Alexander Spence

Dissertations, Master's Theses and Master's Reports

Greenhouse grafting and field trials were conducted to examine the contribution of the RED NAC transcription factor on low nitrogen phenotypes in hybrid poplar (P. tremula x P. alba). Reciprocal grafting trials showed both root and shoot expression contribute to phenotype under low nitrogen conditions, and shoot expression has a leading role in contribution to low-nitrogen phenotype. The impact of RED NAC expression level on auxin polar transport was investigated using a DR5::GUS auxin-responsive reporter gene line as rootstock for RED NAC modified scions. Pilot studies indicate the rate of auxin transport from apex to roots is slower through shoots …

Genetic Diversity Of Paxistima Canbyi A. Gray: Conserving A Rare Plant Species Endemic To The Eastern United States, Isaac Buabeng

Master’s Theses

Premise: The glacial cycles of the Pleistocene period likely had a profound impact on the genetic diversity and phylogeographic patterns of numerous plant taxa in North America. However, the genetic diversity of rare, limestone-endemic woody species has not been highlighted. This study assesses genetic diversity in Paxistima canbyi A. Gray (Canby’s mountain lover or rat stripper), a rare limestone endemic small woody plant.

Methods: We investigated the genetic diversity of P. canbyi using genomic Single Nucleotide Polymorphism (SNP) data from 165 individuals from 14 populations sampled from across the entire range distribution. We first; de novo assembled the SNP …

Inflammation And Tumor Progression: The Differential Impact Of Saa In Breast Cancer Models, Daniel Wilhelm Olivier, Carla Eksteen, Manisha Du Plessis, Louis De Jager, Lize Engelbrecht, Nathaniel Wade Mcgregor, Preetha Shridas, Frederick C. De Beer, Willem J. S. De Villiers, Etheresia Pretorius, Anna-Mart Engelbrecht

Saha Cardiovascular Research Center Faculty Publications

Background: Previous research has shown that the Serum Amyloid A (SAA) protein family is intricately involved in inflammatory signaling and various disease pathologies. We have previously demonstrated that SAA is associated with increased colitis disease severity and the promotion of tumorigenesis. However, the specific role of SAA proteins in breast cancer pathology remains unclear. Therefore, we investigated the role of systemic SAA1 and SAA2 (SAA1/2) in a triple-negative breast cancer mouse model.

Methods: Syngeneic breast tumors were established in wild-type mice, and mice lacking the SAA1/2 (SAADKO). Subsequently, tumor volume was monitored, species survival determined, the inflammatory profiles of mice …

Examining Potential Causal Associations Of Sedentary Time And Physical Activity With Heart Failure Using Subjective And Objective Measures: A Mendelian Randomization Analysis, Jessica Geller

UNF Graduate Theses and Dissertations

Purpose: The objective of this study was to assess the causal relationship between both subjectively and objectively measured sedentary time (ST) and physical activity (PA) with heart failure (HF) risk, utilizing Mendelian Randomization (MR) approach.

Methods: The present MR used genetic instruments identified for self-reported ST and PA extracted from 51 genome wide association studies (GWAS), encompassing data from 703,901 individuals. The GWAS identified 89 independent single nucleotide polymorphisms (SNPs) associated with leisure screen time. Eleven loci were reported to be associated with moderate to vigorous physical activity (MVPA). From another GWAS examining accelerometer-based activities, three loci were found to …

Cyp6g2 Is The Major P450 Epoxidase Responsible For Juvenile Hormone Biosynthesis In Drosophila Melanogaster, Qiangqiang Jia, Liu Yang, Jiamin Wen, Suning Liu, Di Wen, Wei Luo, Weihua Wang, Subba R. Palli, Li Sheng

Entomology Faculty Publications

Background Juvenile hormones (JH) play crucial role in regulating development and reproduction in insects. The most common form of JH is JH III, derived from MF through epoxidation by CYP15 enzymes. However, in the higher dipterans, such as the fruitfly, Drosophila melanogaster, a bis-epoxide form of JHB3, accounted most of the JH detected. Moreover, these higher dipterans have lost the CYP15 gene from their genomes. As a result, the identity of the P450 epoxidase in the JH biosynthesis pathway in higher dipterans remains unknown.

Results In this study, we show that Cyp6g2 serves as the major JH epoxidase responsible for …

Go West: Population Genomics Reveals Unexpected Population Fluctuations And Little Gene Flow In Western Hemisphere Populations Of The Predatory Lady Beetle, Hippodamia Convergens, Arun Sethuraman, Schyler O. Nunziata, Angela Jones, John J. Obrycki, David W. Weisrock

Entomology Faculty Publications

Hippodamia convergens—the convergent lady beetle, has been used extensively in aug- mentative biological control of aphids, thrips, and whiteflies across its native range in North America, and was introduced into South America in the 1950s. Overwintering H. convergens populations from its native western range in the United States are com- mercially collected and released across its current range in the eastern USA, with little knowledge of the effectiveness of its augmentative biological control. Here we use a novel ddRADseq-based SNP/haplotype discovery approach to estimate its range- wide population diversity, differentiation, and recent evolutionary history. Our results indicate (1) significant population …

N(Alpha)-Acetyltransferase 40-Mediated Histone Acetylation Plays An Important Role In Ecdysone Regulation Of Metamorphosis In The Red Flour Beetle, Tribolium Castaneum, Sharath Chandra Gaddelapati, Smitha George, Anilkumar Moola, Karthi Sengodan, Subba Reddy Palli

Entomology Faculty Publications

Histone acetylation, a crucial epigenetic modification, is governed by histone acetyltransferases (HATs), that regulate many biological processes. Functions of HATs in insects are not well understood. We identified 27 HATs and determined their functions using RNA interference (RNAi) in the model insect, Tribolium castaneum. Among HATs studied, N-alpha-acetyltransferase 40 (NAA40) knockdown caused a severe phenotype of arrested larval development. The steroid hormone, ecdysone induced NAA40 expression through its receptor, EcR (ecdysone receptor). Interestingly, ecdysone-induced NAA40 regulates EcR expression. NAA40 acetylates histone H4 protein, associated with the promoters of ecdysone response genes: EcR, E74, E75, and HR3, and causes an increase …

The Mechanoreceptor Piezo Is Required For Spermatogenesis In Bombyx Mori, Zhongjie Zhang, Xiaojing Liu, Bo Hu, Kai Chen, Ye Yu, Chenxin Sun, Dalin Zhu, Hua Bai, Subba Reddy Palli, Anjiang Tan

Entomology Faculty Publications

Background The animal sperm shows high diversity in morphology, components, and motility. In the lepidopteran model insect, the silkworm Bombyx mori, two types of sperm, including nucleate fertile eupyrene sperm and anucleate unfertile apyrene sperm, are generated. Apyrene sperm assists fertilization by facilitating the migration of eupyrene spermatozoa from the bursa copulatrix to the spermatheca. During spermatogenesis, eupyrene sperm bundles extrude the cytoplasm by peristaltic squeezing, while the nuclei of the apyrene sperm bundles are discarded with the same process, forming matured sperm.

Results In this study, we describe that a mechanoreceptor BmPiezo, the sole Piezo ortholog in B. mori, …

Contemporary Vs. Traditional Dna-Based Mutation Testing To Detect Hereditary Breast And Ovarian Cancer Syndrome (Hboc) In Women: A Meta Narrative Review, Hannah Olivia Cantu, Jacob Hipp, Nyela Y. Lopez, Duc Duy Nguyen

Research Methods Poster Session 2024

No abstract provided.

The Genetic Diversity Of An Endangered Buttercup, Ranunculus Triternatus, Ryan Garcia

All Master's Theses

Ranunculus triternatus, a rare endemic species of the Columbia River Gorge, faces conservation challenges due to its limited range and fragmented populations. This study assesses the genetic diversity of R. triternatus and compares it with its widespread congener, Ranunculus glaberrimus, using inter-primer binding site (iPBS) markers. Genetic data from 80 individuals across eight populations were analyzed using Nei’s genetic diversity, Shannon’s diversity index, and AMOVA. Results showed R. triternatus had higher genetic diversity than western populations of R. glaberrimus, with eastern populations of R. glaberrimus displaying greater diversity than western ones. PCA, UPGMA, and STRUCTURE analysis revealed …

Structural And Functional Consequences Of Pde6 Prenylation In Rod And Cone Photoreceptors, Faezeh Moakedi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Phosphodiesterase-6 (PDE6) serves as a pivotal component in the phototransduction pathways of both cone and rod photoreceptors. In cones, PDE6 consists of tetrameric subunits: inhibitory (γ') and catalytic (α'). The catalytic subunit, PDE6α', contains a C-terminal prenylation motif. Deletion of this motif is associated with achromatopsia (ACHM), a form of color blindness. The mechanisms underlying the disease and the roles of PDE6 lipidation in vision remain elusive. Meanwhile, rod PDE6 is composed of α and β catalytic subunits and γ inhibitory subunits, with alterations in the C-terminal "prenylation motif" of PDE6β linked to retinitis pigmentosa (RP) pathology. In this comprehensive …

Editing The Tri5 Gene Of Fusarium Graminearum Using Crispr/Cas9, Madelyn Rae Waters

Honors Program Theses

No abstract provided.

The Genetic Basis Of Two Reproductive Traits In Monkeyflowers: Stigma Closure And Corolla Carotenoids, Rachel Anne Halperin

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Abstract

The interactions between pollinators and flowers have long been a driving force for the evolution of many physical floral traits. Traits such as flower shape, size, color, and smell are just some of these traits that evolve because of these interactions. This evolution does not only occur in the more obvious morphological floral traits, however, but also in more subtle traits like touch sensitive stigma closure. In hundreds of Lamiales species, the bilobed stigma, the organ that receives pollen from pollinators, closes rapidly upon touch. Theory and experiments show that this novel dynamic reproductive trait increases pollen export and …

Strategies For Improving The Performance Of Prediction Models For Response To Immune Checkpoint Blockade Therapy In Cancer, Tiantian Zeng, Jason Z. Zhang, Arnold Stromberg, Jin Chen, Chi Wang

Markey Cancer Center Faculty Publications

Immune checkpoint blockade (ICB) therapy holds promise for bringing long-lasting clinical gains for the treatment of cancer. However, studies show that only a fraction of patients respond to the treatment. In this regard, it is valu- able to develop gene expression signatures based on RNA sequencing (RNAseq) data and machine learning meth- ods to predict a patient’s response to the ICB therapy, which contributes to more personalized treatment strategy and better management of cancer patients. However, due to the limited sample size of ICB trials with RNAseq data available and the vast number of candidate gene expression features, it is …

Vaginal Lactobacillus Fatty Acid Response Mechanisms Reveal A Metabolite-Targeted Strategy For Bacterial Vaginosis Treatment, Paul C. Blainey, Seth M. Bloom, Douglas S. Kwon

Markey Cancer Center Faculty Publications

Bacterial vaginosis (BV), a common syndrome characterized by Lactobacillus-deficient vaginal microbiota, is associated with adverse health outcomes. BV often recurs after standard antibiotic therapy in part because antibiotics promote microbiota dominance by Lactobacillus iners instead of Lactobacillus crispatus, which has more beneficial health associations. Strategies to promote L. crispatus and inhibit L. iners are thus needed. We show that oleic acid (OA) and similar long-chain fatty acids simultaneously inhibit L. iners and enhance L. crispatus growth. These phenotypes require OA-inducible genes conserved in L. crispatus and related lactobacilli, including an oleate hydratase (ohyA) and putative fatty acid efflux pump (farE). …