Molecular Genetics Commons^™

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 …

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.

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 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 …

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 …

Testing For Cryptic Diversity And Inference Of Population Structure In The Cosmopolitan Hoplonemertean Emplectonema Gracile (Nemertea), Paul L. Delaney Iv

Theses and Dissertations

Emplectonema gracile (Johnston 1837) is a hoplonemertean of marine intertidal hard-bottom communities and is distributed throughout the Northern Hemisphere. Although possessing a planktonic larval stage in its life history, the range of such cosmopolitan marine invertebrate species is often explained by cryptic speciation and anthropogenic transport. The purpose of this study is to test for possible cryptic species using mtDNA markers (COI and 16S rDNA) and to investigate population structure in E. gracile over a portion of its geographic range using mtDNA markers and ddRADseq nuclear SNP data. The results of both phylogenetic- and tree-based species delimitation revealed that E. …

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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 …

Association Genetics And Local Adaptation Of Populus Trichocarpa Torr. & Gray, Hari Bahadur Chhetri

Graduate Theses, Dissertations, and Problem Reports (ETD)

A major goal in plant science is overcoming the recalcitrance of plant biomass to cellulose extraction, to enable efficient production of cellulosic biofuel. We have started to understand the genetic basis of some important traits such as cell wall chemistry, but we do not know anything about the key structural and functional traits such as wood anatomy that greatly affect plant biomass recalcitrance. Furthermore, biofuel feedstocks have to be adapted to varied environmental conditions to ensure high productivity in plantations, but little is known about the molecular mechanisms underlying local adaptation. With the advancement in sequencing and genotyping technologies, association …

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 …

Regulated Capture Of Vκ Gene Topologically Associating Domains By Transcription Factories, Sophiya Karki, Domenick E. Kennedy, Kaitlin Mclean, Adrian T. Grzybowski, Mark Maienschein-Cline, Shiladitya Banerjee, Heping Xu, Elizabeth Davis, Malay Mandal, Christine Labno, Sarah E. Powers, Michelle M. Le Beau, Aaron R. Dinner, Harinder Singh, Alexander J. Ruthenburg, Marcus R. Clark

Biology Department Faculty Articles

Expression of vast repertoires of antigen receptors by lymphocytes, with each cell expressing a single receptor, requires stochastic activation of individual variable (V) genes for transcription and recombination. How this occurs remains unknown. Using single-cell RNA sequencing (scRNA-seq) and allelic variation, we show that individual pre-B cells monoallelically transcribe divergent arrays of Vκ genes, thereby opening stochastic repertoires for subsequent Vκ-Jκ recombination. Transcription occurs upon translocation of Vκ genes to RNA polymerase II arrayed on the nuclear matrix in transcription factories. Transcription is anchored by CTCF-bound sites or E2A-loaded Vκ promotors and continues over large genomic distances delimited only by …

The Transcriptome Of The Bermuda Fireworm Odontosyllis Enopla (Annelida: Syllidae): A Unique Luciferase Gene Family And Putative Epitoky-Related Genes, Mercer R. Brugler, M. Teresa Aguado, Michael Tessler, Mark Siddall

Publications and Research

The Bermuda fireworm Odontosyllis enopla exhibits an extremely tight circalunar circadian behavior that results in an impressive bioluminescent mating swarm, thought to be due to a conventional luciferase-mediated oxidation of a light-emitting luciferin. In addition, the four eyes become hypertrophied and heavily pigmented, and the nephridial system is modified to store and release gametes and associated secretions. In an effort to elucidate transcripts related to bioluminescence, circadian or circalunar periodicity, as well as epitoky-related changes of the eyes and nephridial system, we examined the transcriptomic profile of three female O. enopladuring a bioluminescent swarm in Ferry Reach, Bermuda. …

Insight Into Translational Activation In Yeast Mitochondria, Julia Lynn Jones

Graduate School of Biomedical Sciences Theses and Dissertations

Mitochondrial function depends on over a thousand proteins, of which the majority are nuclear DNA-encoded and approximately one percent are mitochondrial DNA-encoded. The mitochondrial DNA of Saccharomyces cerevisiae contains eight protein-encoding genes, seven of which are required for proper function of the respiratory complexes and one encodes a ribosomal protein. The bigenomic nature of the oxidative phosphorylation complexes requires coordinated expression and regulation from both the nuclear and the mitochondrial genomes. It is currently unclear how this regulatory network operates. However, it is thought that nuclear genome-encoded messengers localized to the mitochondria aid in this coordination.

A family of proteins …

Characterizing Epigenetic Regulation In The Developing Chicken Retina, Bejan Abbas Rasoul

Masters Theses, 2010-2019

The retina, the sensory neuronal tissue within the eye, is composed of three layers of neuronal cells connected by two synaptic layers lining the inside of the anterior portion of the eye. Multipotent retinal precursor cells are genetically homogeneous and differentiate into mature retinal neurons due to differential gene expression. Differences in gene expression have been correlated with epigenetic modifications such as DNA methylation. DNA methylation of upstream regulatory elements is associated with transcriptional silencing of gene expression. Years of research in retinal development has identified the numerous genes expressed during the main steps of retinal development, however, it is …

Functional Studies Of The E. Coli Proc And A Putative Ortholog Mrub_1345, Maureen Azar, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses the bioinformatics tools associated with the Guiding Education through Novel Investigation –Annotation Collaboration Toolkit (GENI-ACT) to predict gene function. We investigated the biological function of Escherichia coli and Meiothermus ruber proC genes using the complementation assay. In this research project, mutants of varying severity to the functional state of the protein were developed. The results showed that two or more amino acid deletions reduced or eliminated ProC function. Amino acid substitutions, on the other hand, were not severe enough to impact ProC function. Double and triple mutants …

Phylogeny And Evolutionary Genomics Of Non-Photosynthetic Diatoms, Anastasiia Onyshchenko

Graduate Theses and Dissertations

Diatoms are prolific photosynthesizers responsible for some 20% of global primary production. In real terms, the oxygen in one of every five breaths traces back to photosynthesis by marine diatoms. Among the tens of thousands of diatom species, a small handful of colorless diatom species in the genus Nitzschia have lost photosynthesis altogether and rely exclusively on extracellular organic carbon for growth. I used DNA sequence data to reconstruct the phylogeny of this group, and found that nonphotosynthetic diatoms are monophyletic, indicating that photosynthesis was lost just one time over the course of some 200 million years of diatom evolution. …

Involvement Of The Ino80 Complex In Chromosome Segregation, Jesus Moreno

Graduate Theses and Dissertations

Chromatin remodeling complexes are multi-protein complexes that regulate the dynamics of the nucleosomes in the genome. The INO80 chromatin remodeling complex participates in varied biological processes such as: transcription, DNA repair, DNA replication and chromosome integrity. It catalyzes the eviction of the H2A.Z variant histone as well as whole nucleosome eviction. This complex is comprised of 15 subunits and the contribution of each to chromosome segregations remains unknown. To evaluate the contribution of each subunit to chromosome segregation, we tested deletion mutants of the non-essential subunits for DNA content and benomyl sensitivity. Also, we assessed members of the SWR1 and …

Efficient Reduced Bias Genetic Algorithm For Generic Community Detection Objectives, Aditya Karnam Gururaj Rao

Theses

The problem of community structure identification has been an extensively investigated area for biology, physics, social sciences, and computer science in recent years for studying the properties of networks representing complex relationships. Most traditional methods, such as K-means and hierarchical clustering, are based on the assumption that communities have spherical configurations. Lately, Genetic Algorithms (GA) are being utilized for efficient community detection without imposing sphericity. GAs are machine learning methods which mimic natural selection and scale with the complexity of the network. However, traditional GA approaches employ a representation method that dramatically increases the solution space to be searched by …

Copy Number Variation In The Porcine Genome Detected From Whole-Genome Sequence, Rebecca Anderson

Honors Program: Senior Projects (Public)

Copy number variations (CNVs) are large insertions, deletions, and duplications in the genome that vary between individuals in a species. These variations are known to impact a broad range of phenotypes from molecular-level traits to higher-order clinical phenotypes. CNVs have been linked to complex traits in humans such as autism, attention deficit hyperactivity disorder, nervous system disorders, and early-onset extreme obesity. In this study, whole-genome sequence was obtained from 72 founders of an intensely phenotyped experimental swine herd at the U.S. Meat Animal Research Center (USMARC) in Clay Center, Nebraska. This included 24 boars (12 Duroc and 12 Landrace) and …

Advancing Behavioural Genomics By Considering Timescale, Clare C. Rittschof, Kimberly A. Hughes

Entomology Faculty Publications

Animal behavioural traits often covary with gene expression, pointing towards a genomic constraint on organismal responses to environmental cues. This pattern highlights a gap in our understanding of the time course of environmentally responsive gene expression, and moreover, how these dynamics are regulated. Advances in behavioural genomics explore how gene expression dynamics are correlated with behavioural traits that range from stable to highly labile. We consider the idea that certain genomic regulatory mechanisms may predict the timescale of an environmental effect on behaviour. This temporally minded approach could inform both organismal and evolutionary questions ranging from the remediation of early …

A Model Species For Agricultural Pest Genomics: The Genome Of The Colorado Potato Beetle, Leptinotarsa Decemlineata (Coleoptera: Chrysomelidae), Sean D. Schoville, Yolanda H. Chen, Martin N. Andersson, Joshua B. Benoit, Anita Bhandari, Julia H. Bowsher, Kristian Brevik, Kaat Cappelle, Mei-Ju M. Chen, Anna K. Childers, Christopher Childers, Olivier Christiaens, Justin Clements, Elise M. Didion, Elena N. Elpidina, Patamarerk Engsontia, Markus Friedrich, Inmaculada García-Robles, Richard A. Gibbs, Chandan Goswami, Alessandro Grapputo, Kristina Gruden, Marcin Grynberg, Bernard Henrissat, Emily C. Jennings, Jeffery W. Jones, Megha Kalsi, Sher A. Khan, Abhishek Kumar, Fei Li, Vincent Lombard, Subba Reddy Palli, June-Sun Yoon

Entomology Faculty Publications

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and …

Examination Of Orthologous Genes (Mrub_2518 And B3728, Mrub_2519 And B3727, Mrub_2520 And B3726, Mrub_2521 And B3725) Responsible For Abc Phosphate Transporters In Two Species M. Ruber And E. Coli, Margaret Meyer, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

In this project we investigated the biological function of the genes b3725, b3726, b3727, b3728 and Mrub_2518, Mrub_2519, Mrub_2520 and Mrub_2521 (KEGG map number 02010). We predict that these genes encode the components of a Phosphate ABC transporter: Orthologous genes Mrub_2518 (DNA coordinates 2565359..2566438) and b3728 encodes the periplasmic phosphate binding component; Orthologous genes Mrub_2519 (DNA coordinates 2566499..2567485) and b3727, and Mrub_2520 (DNA coordinates 2567496..2568326) and b3726 encode for the two transmembrane proteins; Orthologous genes Mrub_2521 (DNA coordinates 2568338..2569159) and b3725 encode for the ATP binding protein within the cytoplasm. Within the two species, M. ruber and E. coli, …

Mrub_1325, Mrub_1326, Mrub_1327, And Mrub_1328 Are Orthologs Of B_3454, B_3455, B_3457, B_3458, Respectively Found In Escherichia Coli Coding For A Branched Chain Amino Acid Atp Binding Cassette (Abc) Transporter System, Bennett Tomlin, Adam Buric, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

In this project we investigated the biological function of the genes Mrub_1325, Mrub_1326, Mrub_1327, and Mrub_1328 (KEGG map number 02010). We predict these genes encode components of a Branched Chain Amino Acid ATP Binding Cassette (ABC) transporter: 1) Mrub_1325 (DNA coordinates 1357399-1358130 on the reverse strand) encodes the ATP binding domain; 2) Mrub_1326 (DNA coordinates 1358127-1359899 on the reverse strand) encodes the ATP-binding domain and permease domain; 3) Mrub_1327 (DNA coordinates 1359899-1360930 on the reverse strand) encodes a permease domain; and 4)Mrub_1328 (DNA coordinates 1711022-1712185 on the reverse strand) encodes the substrate binding domain. This system is not predicted to …