Genomics Commons^™

Exploration Of Genes Controlling Grain Yield Heterosis In Hybrid Wheat (Triticum Aestivum L.) Utilizing 3ʹ Rna Sequencing, Nichole Miller

Theses, Dissertations, and Student Research in Agronomy and Horticulture

The implementation and future success of hybrid wheat (Triticum aestivum L.) is impacted by breeders’ inability to create consistent high yielding, high heterosis hybrids. This research addresses this problem by conducting an exploration of transcriptomes from hybrids and parent lines to determine what genes are active in heterotic or non-heterotic hybrids and how their level of expression can explain the phenotype of grain yield heterosis. Using hybrids that showed positive mid-parent heterosis (MPH), classified as heterotic in our study, and negative or no difference MPH hybrids, classified as non-heterotic, differentially expressed genes (DEGs) potentially related to heterosis and hybrid …

Spr-5; Met-2 Maternal Reprogramming Cooperates With The Dream Complex To Regulate Developmental Cell Fates, Jazmin Dozier, Sandra Nguyen, Brandon Carpenter

Symposium of Student Scholars

Histone methylation is a post-transcriptional modification to the N-terminal tails of histone core proteins that regulates DNA accessibility, and consequently, gene expression. Like DNA, histone methylation can be inherited between generations, and is highly regulated during embryonic development. At fertilization, histone methylation must undergo maternal reprogramming to reset the epigenetic landscape in the new zygote. During maternal reprogramming of histone methylation in the nematode, C. elegans, H3K4me (a modification associated with active transcription) is removed by the H3K4 demethylase, SPR-5, and H3K9me (a modification associated with transcriptional repression) is subsequently added by the histone methyltransferase, MET-2. Recently, it was …

Microbial Diversity And Community Structure In Sediments Associated With The Seagrass (Thallassia Testudinum) In Apalachicola Bay, Florida, Rahma Ahmed, Thomas Mcelroy, Troy Mutchler

Symposium of Student Scholars

Seagrass is an angiosperm which provides many ecosystem services in coastal areas, such as providing food, shelter and nurseries for many species, and decreasing the impact of waves on shorelines. A global assessment reported that 29% of known seagrass meadows are in a state of decline due to the effects of human activity. Seagrass is commonly found in shallow marine waters where they form meadows containing a microbiome that plays an important role in providing nutrients for seagrass growth, though little is known about the microorganisms within the seagrass meadow sediments. Our project collected sediments from seagrass meadows and adjacent …

Identifying Molecular Markers For Early Detection Of Toxic Cyanobacteria And Dinoflagellate, Shafqat F. Ehsan

Honors Program Theses and Research Projects

Harmful algal Blooms (HABs) develop when algal colonies grow out of control, causing toxicity or injury to humans, fish, shellfish, marine mammals, and birds. Most HABs of public health concern in saltwater generally are caused by eukaryotic dinoflagellates and diatoms. Prokaryotic cyanobacteria are usually responsible for freshwater blooms although they can contribute to saltwater and brackish blooms too. A common monitoring target of both groups is the saxitoxin-encoding genes. Saxitoxin(STX) is responsible for Paralytic shellfish poisoning, a foodborne illness developed from consumption of STX contaminated shellfish. Each cyanobacterial SXT gene cluster contains a set of core genes, common to all …

Screening For Binding Partners And Protein-Protein Interactions Of A Fungal Transcription Factor- Xdr1, Nishadi Punsara Gallala Gamage

Masters Theses

Clarireedia spp. (formerly Sclerotinia homoeocarpaF.T. Bennett) is the causal agent dollar spot, the most economically important turfgrass disease impacting golf courses in North America. The most effective strategy for dollar spot control is repeated application of multiple classes of fungicides. However, reliance on chemical application has led to resistance to four classes of fungicides as well as multidrug resistance (MDR). Fungi are known to detoxify xenobiotics, like fungicides, through transcriptional regulation of three detoxification phases: modification, conjugation and secretion. Little is known, however, of the protein-protein interactions that facilitate these pathways. Following next-generation RNA sequencing of Clarireedia spp., a …

Genomic Organization And Expression Of The Wc1 Hybrid Coreceptor And Pattern Recognition Receptor On Porcine Gamma Delta T Cells, Lauren Le Page

Doctoral Dissertations

gd T cells are a crucial component of the immune response to a number of increasingly relevant and largely zoonotic pathogens to which efficacious vaccination is lacking. In ruminants and swine, gd T cells represent a major population of peripheral blood and epithelial tissue-resident lymphocytes. gdT cells respond to both protein and non-protein antigens independently of MHC presentation and possess immunological memory. Upon activation, gamma delta T cells illicit a variety of effector functions and play an indispensable role of orchestrating the downstream immune response. These characteristics make gamma delta T cells a promising candidate for recruitment by vaccination, however, …

Applications Of Nanopore Dna Sequencing For Improved Genome Assembly, Daniel Giguere

Electronic Thesis and Dissertation Repository

An organism's genome is the ultimate determinant of its functional potential. Understanding genomes is therefore essential to understand function, and a foundational knowledge of a genome is required transfer functions to and from microorganisms of interest. Sequencing DNA using nanopores is a recent advance that resolves limitations of previous technologies, enabling an improved understanding of genomes. For this thesis, I improved our understanding of microbial genomes by developing novel approaches to analyze long read sequencing data, setting the foundation for future synthetic biology work.

Long sequencing reads have enabled routine assembly of complete bacterial genomes by directly sequencing DNA extracted …

The Large And Small Of It: The Microbiome And Metagenomics, Austin Hopkins, Elaina Gollmar, Jessica Fernandez, Shawn Wolf, Austin Hilverding, Andrew M. Roecker

Pharmacy and Wellness Review

Metagenomics, the analysis of the microbial genome, permits scientists to understand the influences of external sources including diet, metabolism and antibiotics on the human microbiome. Research has revealed the possibility of a core symbiosis between humans and bacteria. The main role of the human microbiome is to aid in digestion, but identified ancillary roles include immunologic homeostasis and infection prevention. Quantifying the composition and variability of the microbiome will help lead to future treatments or preventive strategies against unhealthy change. A variety of methods may be used to define the microbiome, and 16S amplicon sequencing is primarily utilized today. Probiotics …

Characterization Of Streptomyces Nymphaeiformis Sp. Nov., And Its Taxonomic Relatedness To Other Polyhydroxybutyrate-Degrading Streptomycetes, Gary R. Hix, Muhammad S. Khan, Mikayla T. Miller, Elisha C. Napier, Allison L. O'Brien, Roger P. White, Stephen F. Baron Ph.D.

Biology Faculty Scholarship

A polyhydroxybutyrate (PHB)-degrading actinomycete, strain SFB5A^T, was identified as a species of Streptomyces based on its membrane fatty acid profile and the presence of LL-diaminopimelic acid in the cell wall. It formed sporulating mycelia on most agar media, but flat or wrinkled, moist colonies on trypticase soy agar. Spores were smooth, cylindrical, and borne on long, straight to flexuous chains. It produced a light brown diffusible pigment, but not melanin. Comparison of genomic digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values indicated that strain SFB5A^T was related to Streptomyces litmocidini JCM 4394^T , Streptomyces …

Multi-Year Data Analysis And Genomic Selection To Improve The Efficiency Of A Rice Breeding Program, Tommaso Cerioli

LSU Doctoral Dissertations

Plant breeding dramatically improved crops performances during human history and will play a pivotal role in shaping the future of agriculture. However, this activity requires large amount of time and resources. The availability of multi-year datasets and abundant DNA information enables new analyses and breeding approaches that can increase the productivity and efficiency of a breeding program. In recent years, the LSU Rice Breeding Program has implemented marker assisted selection (MAS) and genomic selection (GS) to predict performance of rice genotypes before field testing. The goal of this project was to conduct analyses and test molecular approaches to increase the …

Rare Coding Variants In Rcn3 Are Associated With Blood Pressure, Karen Y. He, Tanika N. Kelly, Heming Wang, Jingjing Liang, Luke Zhu, Brian E. Cade, Themistocles L. Assimes, Lewis C. Becker, Amber L. Beitelshees, Lawrence F. Bielak, Adam P. Bress, Jennifer A. Brody, Yen-Pei Christy Chang, Yi-Cheng Chang, Paul S. De Vries, Ravindranath Duggirala, Ervin R. Fox, Nora Franceschini, Anna L. Furniss, Yan Gao, Donna K. Arnett

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: While large genome-wide association studies have identified nearly one thousand loci associated with variation in blood pressure, rare variant identification is still a challenge. In family-based cohorts, genome-wide linkage scans have been successful in identifying rare genetic variants for blood pressure. This study aims to identify low frequency and rare genetic variants within previously reported linkage regions on chromosomes 1 and 19 in African American families from the Trans-Omics for Precision Medicine (TOPMed) program. Genetic association analyses weighted by linkage evidence were completed with whole genome sequencing data within and across TOPMed ancestral groups consisting of 60,388 individuals of …

Transposon- And Genome Dynamics In The Fungal Genus Neurospora: Insights From Nearly Gapless Genome Assemblies, Diem Nguyen, Valentina Peona, Per Unneberg, Alexander Suh, Patric Jern, Hanna Johannesson

Fungal Genetics Reports

A large portion of nuclear DNA is composed of transposable element (TE) sequences, whose transposition is controlled by diverse host defense strategies in order to maintain genomic integrity. One such strategy is the fungal-specific Repeat-Induced Point mutation (RIP) that hyper-mutates repetitive DNA sequences. While RIP is found across Fungi, it has been shown to vary in efficiency. The filamentous ascomycete Neurospora crassa has been a pioneer in the study of RIP, but data on TEs and RIP from other species in the genus is limited. In this study, we investigated 18 nearly gapless genome assemblies of ten Neurospora species, which …

Long-Read Sequencing Of The Zebrafish Genome Reorganizes Genomic Architecture, Yelena Chernyavskaya, Xiaofei Zhang, Jinze Liu, Jessica S. Blackburn

Molecular and Cellular Biochemistry Faculty Publications

BACKGROUND: Nanopore sequencing technology has revolutionized the field of genome biology with its ability to generate extra-long reads that can resolve regions of the genome that were previously inaccessible to short-read sequencing platforms. Over 50% of the zebrafish genome consists of difficult to map, highly repetitive, low complexity elements that pose inherent problems for short-read sequencers and assemblers.

RESULTS: We used long-read nanopore sequencing to generate a de novo assembly of the zebrafish genome and compared our assembly to the current reference genome, GRCz11. The new assembly identified 1697 novel insertions and deletions over one kilobase in length and placed …

Apoe Genetics Influence Murine Gut Microbiome, Diana J. Zajac, Stefan J. Green, Lance A. Johnson, Steven Estus

Physiology Faculty Publications

Apolipoprotein E (APOE) alleles impact pathogenesis and risk for multiple human diseases, making them primary targets for disease treatment and prevention. Previously, we and others reported an association between APOE alleles and the gut microbiome. Here, we evaluated effects of APOE heterozygosity and tested whether these overall results extended to mice maintained under ideal conditions for microbiome analyses. To model human APOE alleles, this study used APOE targeted replacement (TR) mice on a C57Bl/6 background. To minimize genetic drift, homozygous APOE3 mice were crossed to homozygous APOE2 or homozygous APOE4 mice prior to the study, and the resulting …

Conservation, Comparative Genomics And Species Delimitation Of The Reindeer Lichens (Cladonia), Jordan R. Hoffman

Dissertations, Theses, and Capstone Projects

The genus Cladonia represents one of the most speciose genera of lichenized fungi, with more than 500 known species encompassing a diverse array of morphologies and habits. These lichens form keystone species in many habitats, serving a variety of ecological roles. However, despite being among of the more well studied lichens, there is much still unknown or under-studied about them. As is the case with most lichen study systems, phylogenetic study has been limited to a small number of partial loci, while adoption of next-generation sequence methods has been slow. As a consequence, there are still knowledge gaps in Cladonia …

The Genetics Of Pain: An Exploration Of Gene-By-Environment Interactions And Their Effects On Pain, Mohamad F. Fakhereddin

Electronic Thesis and Dissertation Repository

The findings presented in this dissertation are part of the bigger SYMBIOME project which aims to use the biopsychosocial model of pain to develop a prognostic clinical phenotype for people that experience musculoskeletal (MSK) trauma. Chapter 2 presents an exploratory analysis to assess the relationships between genetic polymorphisms and pain severity and interference. Early childhood trauma was also explored as a moderator between genetic polymorphisms and pain outcomes. For pain severity, major allele carriers (A/A and G/A) of FKBP5 rs9394314 reported significantly higher scores than minor allele carriers (G/G). Further, major allele carriers who had at least one adverse childhood …

Chromomap: An R Package For Interactive Visualization Of Multi-Omics Data And Annotation Of Chromosomes, Lakshay Anand, Carlos M. Rodriguez Lopez

Horticulture Faculty Publications

BACKGROUND: The recent advancements in high-throughput sequencing have resulted in the availability of annotated genomes, as well as of multi-omics data for many living organisms. This has increased the need for graphic tools that allow the concurrent visualization of genomes and feature-associated multi-omics data on single publication-ready plots.

RESULTS: We present chromoMap, an R package, developed for the construction of interactive visualizations of chromosomes/chromosomal regions, mapping of any chromosomal feature with known coordinates (i.e., protein coding genes, transposable elements, non-coding RNAs, microsatellites, etc.), and chromosomal regional characteristics (i.e. genomic feature density, gene expression, DNA methylation, chromatin modifications, etc.) of organisms …

Phylogenetic And Geographic Relationships Of Cheilostome Bryozoans In The Eastern Pacific, Hannah E. Lee

Cal Poly Humboldt theses and projects

The phylum Bryozoa is an incredibly diverse group of marine invertebrates with a widespread global distribution that is well suited for evolutionary studies but whose phylogenetic relationships are still poorly understood. Although recent studies on bryozoan taxonomies and phylogenies have increased, there is still a lack of assessment of species found at shallow water (<1 m) to intertidal depths. In this study, I aimed to expand the taxonomic sampling and assessment of the phylogenetic diversity of cheilostome bryozoans along the California coastline by utilizing mitochondrial DNA as well as inferring potential correlations between species presence and dispersal range both within and between rocky outer coast and sheltered harbor habitats. Illumina high-throughput sequencing was used to produce mitogenomes for cheilostome bryozoan samples collected off rocks from two rocky intertidal sites and off settlement panels from two harbor sites. Phylogenetic analyses generated evolutionary hypotheses of species relationships alongside geographic mapping of their distribution. This study identified 15 distinct species that represent 10 different families to form the first comprehensive phylogeny for multiple bryozoan families in California across a total range of approximately 973 km of coastline. Three genetically distinct species were found at multiple sites that are separated by a combination of rocky shores and sandy beaches, which indicates that the dispersal range of these species are not limited by geographic barriers along the coast of California. These results provide a future opportunity for further integration of this data with the phylogenies generated in this study to examine more robust evolutionary hypotheses for the phylogenetic and geographic relationships of Californian bryozoan species.

Fathmm: Frameshift Aware Translated Hidden Markov Models, Genevieve Krause

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

An Integrative Investigation Of The Synechococcus A/B Clade During Adaptive Radiation At The Upper Thermal Limit Of Phototrophy, Christopher L. Pierpont

Graduate Student Theses, Dissertations, & Professional Papers

Thermophilic microorganisms have been scientifically observed since the early nineteenth century and have spurred many questions about the limits of life and the capacity of organisms to survive extreme conditions. Decades of research on thermophile proteins and genomes have yielded several proposed correlates of temperature that may contribute to adaptation of bacteria and archaea to high temperature. However, many of the generalizations reported are drawn from analyses of deeply divergent taxa or from individual case studies in isolation from mesophilic relatives. Members of the Synechococcus A/B (SynAB) group are the only cyanobacteria with members able to grow above 65 °C …