Genomics Commons^™

Genomics Based Approaches To Fungal Evolution, Aaron J. Robinson, Donald O. Natvig

Biology ETDs

Advances in DNA sequencing and data analysis make it possible to address questions in population genetics and evolution at the genomic level. Fungi are excellent subjects for such studies, because they are found in diverse environments, have short generation times, can be maintained in culture and have relatively small genomes. My research employed genetic approaches using a variety of sequencing technologies and methods of analysis to explore questions in fungal evolution.

In one study, I explored the genetics behind differences in thermotolerance between isolates of Neurospora discreta from Alaska and New Mexico. Isolates from the two states exhibited differences in …

Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

One of the major goals in large-scale genomic studies is to identify genes with a prognostic impact on time-to-event outcomes which provide insight into the disease's process. With rapid developments in high-throughput genomic technologies in the past two decades, the scientific community is able to monitor the expression levels of tens of thousands of genes and proteins resulting in enormous data sets where the number of genomic features is far greater than the number of subjects. Methods based on univariate Cox regression are often used to select genomic features related to survival outcome; however, the Cox model assumes proportional hazards …

Supervised Dimension Reduction For Large-Scale "Omics" Data With Censored Survival Outcomes Under Possible Non-Proportional Hazards, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

The past two decades have witnessed significant advances in high-throughput ``omics" technologies such as genomics, proteomics, metabolomics, transcriptomics and radiomics. These technologies have enabled simultaneous measurement of the expression levels of tens of thousands of features from individual patient samples and have generated enormous amounts of data that require analysis and interpretation. One specific area of interest has been in studying the relationship between these features and patient outcomes, such as overall and recurrence-free survival, with the goal of developing a predictive ``omics" profile. Large-scale studies often suffer from the presence of a large fraction of censored observations and potential …

Mrub_3019 Casa Gene Is An Ortholog To E. Coli B2760, Kelsey Heiland, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This research is part of the Meiothermus ruber genome annotation project which aims to predict gene function with various bioinformatics tools. We investigated the function of Mrub_3019, which encodes the CasA protein involved in the multi-subunit effector complex for the CRISPR-Cas immunity system and predicted it to be an ortholog of E. coli K12 MG1655 b2760 (casA). We predicted that Mrub_3019 encodes the protein CasA, which is involved in PAM recognition of CRISPR interference pathway. Foreign DNA will bind to CasA, which signals Cas3 for helicase-mediated DNA degradation. Our hypothesis is supported by low E-values for pairwise alignment in NCBI …

Mrub_3015 Is Orthologous To The B2757 Gene Found In Escherichia Coli Coding For Casd, Ramona Collins, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses a collection of online bioinformatics tools to predict gene function. We investigated the biological function of the gene Mrub_3015, which we hypothesize is a component of the CRISPR-Cas prokaryotic defense system. We predict that Mrub_3015 (DNA coordinates 3055550...3056245) encodes the the CRISPR-associated protein cas5, which is integral in maintaining the crRNA-DNA structure, keeping the complex from base pairing with the target phage DNA. Our hypothesis is supported by identical hits for Mrub_3015 and b2527 to the KEGG, Pfam, TIGRfam, CDD and PDB databases as well as a …

Mrub_3018 Is Orthologous To E. Coli B2759 (Casb), Kyle Parker, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses a collection of online bioinformatics tools to predict gene function. We studied the biological activity of the Mrub_3018 gene, which we hypothesize is orthologous to E. coli gene B2759. We predicted that Mrub_3018(DNA coordinates 3057916… 3058524) encodes the protein CasB. CasB is a protein in the CRISPR CASCADE that will function as a structural protein. When the rest of the proteins form an “S” formation CasB will connect the front and back of the “S” creating a back bone for the structure. It will help bind DNA …

Activation Of The Bile Acid Pathway And No Observed Antimicrobial Peptide Sequences In The Skin Of A Poison Frog, Megan L. Civitello, Robert Denton, Michael A. Zasloff, John H. Malone

Biology Publications

The skin secretions of many frogs have genetically-encoded, endogenous antimicrobial peptides (AMPs). Other species, especially aposematic poison frogs, secrete exogenously derived alkaloids that serve as potent defense molecules. The origins of these defense systems are not clear, but a novel bileacid derived metabolite, tauromantellic acid, was recently discovered and shown to be endogenous in poison frogs (Mantella, Dendrobates, and Epipedobates). These observations raise questions about the evolutionary history of AMP genetic elements, the mechanism and function of tauromatellic acid production, and links between these systems. To understand the diversity and expression of AMPs among frogs, we assembled skin transcriptomes of …

A Chromosome-Scale Assembly Of The Axolotl Genome, Jeramiah J. Smith, Nataliya Y. Timoshevskaya, Vladimir A. Timoshevskiy, Melissa C. Keinath, Drew Hardy, S. Randal Voss

Biology Faculty Publications

The axolotl (Ambystoma mexicanum) provides critical models for studying regeneration, evolution, and development. However, its large genome (∼32 Gb) presents a formidable barrier to genetic analyses. Recent efforts have yielded genome assemblies consisting of thousands of unordered scaffolds that resolve gene structures, but do not yet permit large-scale analyses of genome structure and function. We adapted an established mapping approach to leverage dense SNP typing information and for the first time assemble the axolotl genome into 14 chromosomes. Moreover, we used fluorescence in situ hybridization to verify the structure of these 14 scaffolds and assign each to its …

Distribution And Population Structure Of The Invasive Nitellopsis Obtusa (Desv. In Loisel.) J. Groves And Native Species Of Characeae In The Northeast U.S.A., Robin Sleith

Dissertations, Theses, and Capstone Projects

Freshwater ecosystems are some of the most biologically diverse environments on Earth. Billions of humans rely on functioning freshwater ecosystems for drinking water and many other services. These ecosystems are increasingly threatened by human impacts including nutrient pollution, invasive species, and climate change. Here I contribute four research chapters that investigate freshwater diversity and ecosystem threats using the Characeae, a family of freshwater green macroalgae, as a study system. Characeae are a diverse and ancient group with more than 500 extant species and a fossil history spanning at least 250 million years. These algae are macrophytes in freshwater ecosystems, and …

Phylogenetic History Of The Amy Gene Cluster In Catarrhines, Christian M. Gagnon

Theses and Dissertations

This study phylogenetically analyzed 30 AMY-related genes from 11 primates. The results show the gradual expansion of the AMY gene family which could have allowed primates to adapt to various ecological landscapes and maximize energy intake from starch-rich foods in periods of food scarcity.

Characterization Of Immunomodulatory Microbial Factors In Medicinal Plants, Kriti Kalpana

Dissertations, Theses, and Capstone Projects

Medicinal plants are one of the biggest sources of natural products with therapeutic importance. There are currently over 28,000 plants with putative medicinal values. Plant-derived compounds have been explored extensively for various biological activities ranging from anti-cancer, immune-boosting to anti-inflammatory and anti-oxidant. Some of the most important therapeutic agents are of plant-origin, such as paclitaxel from Pacific yew (Taxus brevifolia) and artemisinin from qinghao su (a Chinese medicinal herb; a.k.a. Artemisia annua) to name a few.

The study presented in this thesis started out as classical pharmacognosy research, which focused on the identification of immunostimulatory factors in …

A Phewas Study Of A Large Observational Epidemiological Cohort Of African Americans From The Regards Study, Xueyan Zhao, Xin Geng, Vinodh Srinivasasainagendra, Ninad Chaudhary, Suzanne Judd, Virginia Wadley, Orlando M. Gutiérrez, Henry Wang, Ethan M. Lange, Leslie A. Lange, Daniel Woo, Frederick W. Unverzagt, Monika Safford, Mary Cushman, Nita Limdi, Rakale Quarells, Donna K. Arnett, Marguerite R. Irvin, Degui Zhi

Epidemiology and Environmental Health Faculty Publications

Background: Cardiovascular disease, diabetes, and kidney disease are among the leading causes of death and disability worldwide. However, knowledge of genetic determinants of those diseases in African Americans remains limited.

Results: In our study, associations between 4956 GWAS catalog reported SNPs and 67 traits were examined among 7726 African Americans from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, which is focused on identifying factors that increase stroke risk. The prevalent and incident phenotypes studied included inflammation, kidney traits, cardiovascular traits and cognition. Our results validated 29 known associations, of which eight associations were reported for the …

Gene Co-Expression Networks Analysis Reveal Novel Molecular Endotypes In Alpha-1 Antitrypsin Deficiency, Jen-Hwa Chu, Wenlan Zang

Yale Day of Data

Rationale:Alpha-1 antitrypsin deficiency (AATD) is a genetic condition that predisposes to early onset pulmonary emphysema and airways obstruction. The exact mechanism through which AATD leads to lung disease is incompletely understood.

Objectives: To investigate the effect of AAT genotype and augmentation therapy on bronchoalveolar lavage (BAL) and peripheral blood mononuclear cells (PBMC) transcriptome, while examining the link between gene expression profiles, and clinical features of AATD.

Methods: We performed RNA-Seq on RNA extracted from BAL and PBMC on samples obtained from 89 AATD patients enrolled in the Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis (GRADS) study. Differential …

Non-Invasive Analysis Of The Sputum Transcriptome Discriminates Clinical Phenotypes Of Asthma, Xiting Yan

Yale Day of Data

Whole transcriptome wide gene expression profiles in the sputum and circulation from 100 asthma patients were measured using the Affymetrix HuGene 1.0ST arrays. Unsupervised clustering analysis based on pathways from KEGG were used to identify TEA clusters of patients from the sputum gene expression profiles. The identified TEA clusters have significantly different pre-bronchodilator FEV1, bronchodilator responsiveness, exhaled nitric oxide levels, history of hospitalization for asthma and history of intubation. Evaluation of TEA clusters in children from Asthma BRIDGE cohort confirmed the identified differences in intubation and hospitalization. Furthermore, evaluation of the TH2 gene signatures suggested a much lower prevalence of …

A Novel Pathway-Based Distance Score Enhances Assessment Of Disease Heterogeneity In Gene Expression, Yunqing Liu, Xiting Yan

Yale Day of Data

Distance-based unsupervised clustering of gene expression data is commonly used to identify heterogeneity in biologic samples. However, high noise levels in gene expression data and the relatively high correlation between genes are often encountered, so traditional distances such as Euclidean distance may not be effective at discriminating the biological differences between samples. In this study, we developed a novel computational method to assess the biological differences based on pathways by assuming that ontologically defined biological pathways in biologically similar samples have similar behavior. Application of this distance score results in more accurate, robust, and biologically meaningful clustering results in both …

Order, Please! Uncertainty In The Ordinal-Level Classification Of Chlorophyceae, Karolina Fucikova, Paul O. Lewis, Suman Neupane, Kenneth G. Karol, Louise A. Lewis

Biological and Physical Sciences Department Faculty Works

Background. Chlorophyceae is one of three most species-rich green algal classes and also the only class in core Chlorophyta whose monophyly remains uncontested as gene and taxon sampling improves. However, some key relationships within Chlorophyceae are less clear-cut and warrant further investigation. The present study combined genome-scale chloroplast data and rich sampling in an attempt to resolve the ordinal classification in Chlorophyceae. The traditional division into Sphaeropleales and Volvocales (SV), and a clade containing Oedogoniales, Chaetopeltidales, and Chaetophorales (OCC) was of particular interest with the addition of deeply branching members of these groups, as well as the placement of several …

Multigenerational Genomic And Epigenetic Effects Of Manufactured Silver Nanomaterials In Caenorhabditis Elegans, Anye Wamucho

Theses and Dissertations--Toxicology and Cancer Biology

There has been an increase in the incorporation of silver nanomaterials into consumer products due to their antimicrobial properties. Therefore there is potential for silver nanoparticles (Ag-NPs) to leach out into the environment during different life-cycle stages of these nanomaterial-containing products. Concern about the toxicity of Ag-NPs has led to investigations into their toxic effects on a variety of organisms mainly using acute and sub-chronic, single-generation exposures. The focus of this project was to understand the effects of long-term continuous multigenerational exposure to AgNO₃ and Ag-NPs in both pristine and environmentally transformed forms, on the model organism, Caenorhabditis elegans …

Mrub_3014 Is Orthologous To B2756, Samir Abdelkarim, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses a collection of online bioinformatics tools to predict gene function. We investigated the biological function of the gene Mrub_3014, which we hypothesize is a component of the CRISPR-Cas prokaryotic defense system. We predict that Mrub_3014 (DNA coordinates 3054943..3055575) encodes CRISPR-associated protein Cse3/case which function as an endonuclease. Our hypothesis is supported by identical hits for Mrub_3014 and b2756 to the KEGG, Pfam, TIGRfam, CDD and PDB databases, as well as a low E-value for a pairwise NCBI BLAST comparison. Both protein products are predicted to be localized …

M. Ruber Mrub_3013 Is Orthologous To E. Coli B2755, Laura Butcher, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses a collection of online bioinformatics tools to predict gene function. We investigated the biological function of gene Mrub_3013, which we hypothesize is orthologous to b2755 in E. coli K12 MG1655 (a.k.a. Cas1). We investigated the biological function of a gene with the M. ruber locus tag of Mrub_3013, which we hypothesize is a component of the CRISPR-Cas prokaryotic defense system in M. ruber. We predict that Mrub_3013 (DNA coordinates 3,053,978-3,054,940) encodes the protein Cas1 which as part of the CRISPR-Cas system, selects and cuts the foreign …

Mrub_3020, A Paralog Of Mrub_1489, Is Orthologous To E. Coli Casc (Locus Tag B2761), Alfred Dei-Ampeh, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses a collection of online bioinformatics tools to predict gene function. We investigated the biological functions of two genes: mrub_3020 and mrub_1489. We make two hypotheses in this investigation: a) mrub_3020 is orthologous to the gene b2761 in E. coli K12 MG1655 (a.k.a. casC); b) mrub_1489 is a paralog of mrub_3020. We also predict that the two genes encode unique proteins: mrub_3020 with DNA coordinates 3060491…3063190 encodes a CRISPR – associated helicase (Cas3) that supports the Cascade complex of the CRISPR – Cas adaptive immune system …

Effects Of Temperature On Crispr/Cas System, Eddie Beckom, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses a collection of online bioinformatics tools to predict gene function. We investigated the effect of temperature on the complexity of CRISPR/Cas systems in bacterial organisms across temperature classifications. We predict that temperature extremes would result in CRISPR/Cas systems with multiple operons, repeating cas genes, and complex systems. CRISPR/Cas systems can be classified into three types with a number of subtypes based on the CRISPR-associated genes, cas genes, present in a given organism. Our hypothesis is supported by the presence of multiple operons in thermophilic organisms based on …

Comparative Analysis Of Four Dna Preparation Kits For Quercus Falcata, Palustris, And Rubra Dna Extractions And Subsequent Dna Sequencing, Devin Cummins, Timothy D. Trott

Research in Biology

In 2011, of the 8.7 million species of lif suspected to populate the globe only 1.2 million had been catalogued and it was estimated that 1,200 years would pass before the remainder were processed, allowing the possibility that some species would go extinct before they were even discovered (Mora, Tittensor, Adl, Simpson, & Worm, 2011). DNA barcoding may provide an answer to this problem. According to Hebert and Gregory, “DNA barcoding will accelerate the pace of species discovery by allowing taxonomists to rapidly sort specimens... by highlighting divergent taxa that may represent new species… and by making species identifications more …

Effects Of Suv39h1 And Suv420h1/H2 On Programmed Genome Rearrangement In Petromyzon Marinus, Claire A. Scott

Oswald Research and Creativity Competition

The sea lamprey (Petromyzon marinus), diverged from the vertebrate lineage roughly 550 million years ago, prior to the evolution of several major morphological features such as jaws and paired fins/appendages. Lamprey therefore provides a comparative perspective that can be used to study the evolution of differences in genome regulation, including epigenetics and programmed genome rearrangement (PGR). Programmed genome rearrangement is a unique regulatory mechanism wherein specific genes are effectively turned off by completely eliminating their sequences from the genome. Through PGR, lamprey delete approximately 20% of their genome from all somatic cells, with these specific sequences being only …

Transcription Factor Binding Site Clusters Identify Target Genes With Similar Tissue-Wide Expression And Buffer Against Mutations., Peter Rogan, Ruipeng Lu

Biochemistry Publications

Background: The distribution and composition of cis-regulatory modules composed of transcription factor (TF) binding site (TFBS) clusters in promoters substantially determine gene expression patterns and TF targets. TF knockdown experiments have revealed that TF binding profiles and gene expression levels are correlated. We use TFBS features within accessible promoter intervals to predict genes with similar tissue-wide expression patterns and TF targets using Machine Learning (ML). Methods: Bray-Curtis Similarity was used to identify genes with correlated expression patterns across 53 tissues. TF targets from knockdown experiments were also analyzed by this approach to set up the ML framework. TFBSs were …

Impact Of Industrial Biocides On Bacterial Isolates From Hydraulic Fracturing Produced Water, Waad Ahmed Aljohani

Dissertations, Master's Theses and Master's Reports

Biocides are antimicrobial compounds that are designed to kill diverse groups of microbes in an untargeted fashion. Glutaraldehyde and DBNPA are commonly used to manage microbial growth in different industries. It is possible that biocide use may result in the development of bacterial resistance. However, resistance to DBNPA is believed to be limited under normal use conditions. We isolated a number of bacteria from produced water from a hydraulically fractured site in West Texas. We then tested the ability of these isolates to resist Glutaraldehyde and DBNPA. In this study, we found that these isolates have varying resistance to these …

Computational Tools For The Dynamic Categorization And Augmented Utilization Of The Gene Ontology, Eugene Waverly Hinderer Iii

Theses and Dissertations--Molecular and Cellular Biochemistry

Ontologies provide an organization of language, in the form of a network or graph, which is amenable to computational analysis while remaining human-readable. Although they are used in a variety of disciplines, ontologies in the biomedical field, such as Gene Ontology, are of interest for their role in organizing terminology used to describe—among other concepts—the functions, locations, and processes of genes and gene-products. Due to the consistency and level of automation that ontologies provide for such annotations, methods for finding enriched biological terminology from a set of differentially identified genes in a tissue or cell sample have been developed to …

Forms Of Supplemental Selenium In Vitamin-Mineral Mixes Differentially Affect Serological And Hepatic Parameters Of Growing Beef Steers Grazing Endophyte-Infected Tall Fescue, Yang Jia

Theses and Dissertations--Animal and Food Sciences

Consumption of endophyte-infected tall fescue results in a syndrome of negatively altered physiological systems, collectively known as fescue toxicosis. Another challenge to endophyte-infected tall fescue -based beef cattle operations is that the soils often are selenium (Se) poor, necessitating the need to provide supplemental Se. To test the general hypothesis that different forms of supplemental Se would ameliorate the negative effects of fescue toxicosis, predominately-Angus steers (BW = 183 ± 34 kg) were randomly selected from herds of fall-calving cows grazing an endophyte-infected tall fescue pasture and consuming vitamin-mineral mixes that contained 35 ppm Se as sodium selenite (ISe), SELPLEX …

Genome-Wide Systems Genetics Of Alcohol Consumption And Dependence, Kristin Mignogna

Theses and Dissertations

Widely effective treatment for alcohol use disorder is not yet available, because the exact biological mechanisms that underlie this disorder are not completely understood. One way to gain a better understanding of these mechanisms is to examine the genetic frameworks that contribute to the risk for developing this disorder. This dissertation examines genetic association data in combination with gene expression networks in the brain to identify functional groups of genes associated with alcohol consumption and dependence.

The first study took advantage of the behavioral complexity of human samples, and experimental capabilities provided by mouse models, by co-analyzing gene expression networks …

Effects Of Commercial Formulations Of Glyphosate On Saccharomyces Cerevisiae, Apoorva Ravi Shankar

Graduate Theses, Dissertations, and Problem Reports

Commercial formulations of glyphosate are among the most extensively used herbicides around the world. The active ingredient, glyphosate, targets the aromatic amino acid pathway. This pathway is absent in mammals, resulting in low toxicity. Different formulations contain varying adjuvants and surfactants, whose synergistic effects are yet to be extensively studied at the cellular level. In this study, I tested multiple commercial formulations that showed a variation in growth phenotype among different yeast strains. To gain a better understanding of response and resistance mechanisms at the genome and transcriptome level, I carried out an in-lab evolution study, along with a transcriptome …

Effects Of A Systemic High Urea Concentration On The Endometrial And Embryonic Transcriptomes Of The Mare, Yatta Linhares Boakari

Theses and Dissertations--Veterinary Science

Pregnancy loss remains a major source of economic cost to the equine industry. Frequently, the exact causes of pregnancy loss remain unknown. It has been shown, in other species, that increased dietary protein leading to elevated blood urea nitrogen concentrations (BUN) can be a factor in decreased survival of the early embryo. Our studies provided novel information regarding the effects of elevated BUN on endometrium and embryos from mares as well as insights on changes in their gene expression. Our first objective was to develop an experimental model to elevate BUN during diestrus using intravenous urea infusion. We analyzed the …