Computational Biology Commons^™

Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount

LSU Doctoral Dissertations

Identifying the source and structure of variation in nature is crucial to understanding fundamental aspects of evolution. Despite a recent plethora of genetic and morphological data, many interesting questions about the relationships between different groups remain unresolved. My dissertation evaluates three approaches for identifying and quantifying the variation within phylogenetic datasets. Characterizing variation within datasets and across analytical methods gives insight into biologically interesting characters, unusual evolutionary processes, and areas for model improvement.

Network-based community detection approaches offer a powerful tool to describe variation in phylogenetic signal across the genome (i.e., gene tree variation). In Chapter 2, I investigate the …

Not Withering On The Evolutionary Vine: Systematic Revision Of The Brown Vine Snake (Reptilia: Squamata: Oxybelis) From Its Northern Distribution, Robert C. Jadin, Christopher Blair, Sarah A. Orlofske, Michael J. Jowers, Gilson A. Rivas, Laurie J. Vitt, Julie M. Ray, Eric N. Smith, John C. Murphy

Publications and Research

The genus Oxybelis currently is composed of four taxa despite numerous studies suggesting and describing multiple taxa within the O. aeneus complex. Here, we utilize a multilocus molecular dataset (i.e. cyt b, ND4, 12S, 16S, cmos, PRLR, 3663 bp) to conduct phylogenetic analyses to assess the evolutionary history of Oxybelis. Our molecular analyses find three major lineages of Oxybelis (i.e. O. aeneus complex, O. brevirostris, O. fulgidus complex) with a sister relationship between O. brevirostris and the O. aeneus complex to the exclusion of the O. fulgidus complex. More specifically, O. aeneus appears to harbor at least …

Machine Learning Applications For Drug Repurposing, Hansaim Lim

Dissertations, Theses, and Capstone Projects

The cost of bringing a drug to market is astounding and the failure rate is intimidating. Drug discovery has been of limited success under the conventional reductionist model of one-drug-one-gene-one-disease paradigm, where a single disease-associated gene is identified and a molecular binder to the specific target is subsequently designed. Under the simplistic paradigm of drug discovery, a drug molecule is assumed to interact only with the intended on-target. However, small molecular drugs often interact with multiple targets, and those off-target interactions are not considered under the conventional paradigm. As a result, drug-induced side effects and adverse reactions are often neglected …

Linking Crude Oil And Dispersant Effects To Gene Expression Of Marine Sponge Cinachyrella, Yvain Desplat

All HCAS Student Capstones, Theses, and Dissertations

Because of their filter-feeding lifestyle, sponges (Phylum Porifera) have shown to be bio-accumulators of heavy metals, and bio-monitors for polychlorobiphenyl (PCB) contaminants. Furthermore, marine sponges have been shown to be regulators of reef ecosystems by fulfilling many ecological functions. However, very little is known about their behavior in the face of environmental changes. Consequently, our lab has developed the reef sponge Cinachyrella spp. as novel experimental model. We have designed an experiment to study the effects of WAF (Water Accommodated Fraction), Corexit 9500 dispersant, and CE-WAF (Chemically Enhanced Water Accommodated Fraction)mixtures, in an effort to mimic the conditions of the …

Identification Of Trim24 Domain Essentiality In Primary Trim24coe Carcinosarcoma Cell Lines, Cem Dede

Dissertations and Theses (Open Access)

Regulation of transcriptional control is a critical feature for organismal development and survival. Because of its effects on chromatin-controlled expression, disruptions of this delicately tuned mechanism are an important factor in development of tumorigenesis. Therefore, there is a growing interest in targeting these control mechanisms for their potential therapeutic values.

Our lab previously discovered the epigenetic regulator function of Tripartite motif protein 24 (TRIM24) through its H3K4me0 and H3K23ac dual histone signature reader function, its negative regulatory effect on the p53 tumor suppressor, in addition to its shown oncogenic driving capacity on immortalized mammary epithelial cells when overexpressed. Although TRIM24 …

Statistical Methods For Resolving Intratumor Heterogeneity With Single-Cell Dna Sequencing, Alexander Davis

Dissertations and Theses (Open Access)

Tumor cells have heterogeneous genotypes, which drives progression and treatment resistance. Such genetic intratumor heterogeneity plays a role in the process of clonal evolution that underlies tumor progression and treatment resistance. Single-cell DNA sequencing is a promising experimental method for studying intratumor heterogeneity, but brings unique statistical challenges in interpreting the resulting data. Researchers lack methods to determine whether sufficiently many cells have been sampled from a tumor. In addition, there are no proven computational methods for determining the ploidy of a cell, a necessary step in the determination of copy number. In this work, software for calculating probabilities from …

Metabolic Network Analysis Of Filamentous Cyanobacteria, Daniel Alexis Norena-Caro

LSU Doctoral Dissertations

Cyanobacteria were the first organisms to use oxygenic photosynthesis, converting CO₂ into useful organic chemicals. However, the chemical industry has historically relied on fossil raw materials to produce organic precursors, which has contributed to global warming. Thus, cyanobacteria have emerged as sustainable stakeholders for biotechnological production. The filamentous cyanobacterium Anabaena sp. UTEX 2576 can metabolize multiple sources of Nitrogen and was studied as a platform for biotechnological production of high-value chemicals (i.e., pigments, antioxidants, vitamins and secondary metabolites). From a Chemical engineering perspective, the biomass generation in this organism was thoroughly studied by interpreting the cell as a microbial …

The Evolution Of Bivalve Shell Matrix Proteins, Mark Ira Duhon Ii

LSU Doctoral Dissertations

This dissertation focuses on the molecular underpinnings surrounding the evolution of the biomineralized shells of marine bivalves. Bivalve molluscs synthesize remarkably complex shells from calcium carbonate and an organic matrix of proteins secreted from the dorsal edge of the mantle. Molecular analyses of shell matrix proteins (SMPs) have suggested high rates of gene turnover despite the conserved nature of the shell itself. Here, I used proteomic and transcriptomic data to identify the SMPs and other biomineralization proteins from seven bivalve species that diverged 3-513 Mya. Contrary to previous studies that identified only a few shared biomineralization transcripts across the Bivalvia, …

Statistical Inference Of Adaptation At Multiple Genomic Scales Using Supervised Classification And A Hidden Markov Model, Lauren A. Sugden

Biology and Medicine Through Mathematics Conference

No abstract provided.

Comparative Analysis Of Metabolic Pathways Of Bacteria Used In Fermented Food, Keanu Hoang, Kiran Bastola

Theses/Capstones/Creative Projects

This study presents a novel methodology for analyzing metabolic pathways. Utilizing KEGG REST API through a Biopython package and file parser, data about whether or not a bacteria has an enzyme or not was extracted. The results found that differences in metabolic pathway enrichment values follow along the lines of genera and pathway type. In particular, bacteria found in food spoilage and commercial nitrogen fixing products had high values of enrichment.

Meta-Analysis Of Biological Research Literature, Evan Suggs

Honors Theses

Comparative studies have been powerful tools in generating a broad understanding about the evolution of animal social systems but they currently rely on the slow, manual process of reading thousands of abstracts and papers from research databases. A web application was created for researchers conducting a comparative survey, in order to speed up their research. This web application automates the retrieval of research papers and their selection process. Using previously obtained data sets on the orders Artiodacytla and Lagomorph, a machine learning application was created to classify the papers. These techniques and tools should greatly increase the speed at which …

Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes, Nehal Navali

Honors Scholar Theses

Over two million tons of feather waste is generated annually by the poultry industry, the majority of which goes into landfills due to the difficulty of degrading its major component keratin. Although a portion of feather waste is eliminated via incineration or chemical treatment, the use of Feather Degrading Bacteria (FDB) has been proposed as a cheap and eco-friendly alternative. FDBs have been consistently isolated from the feather microbiome of birds and contain genes coding for the specialized protein keratinase which is able to degrade feathers. By doing so, feather waste, which is rich in nutrients, can be repurposed as …

Evolutionary And Ecological Determinism Of Host Specificity In Arthropod Parasites, Joseph Levey

UCARE: Research Products

Understanding why some diseases infect more species than others is crucial for predicting where and when disease will spread, which can inform the management of wildlife, agriculture, and human health. Currently, large scale patterns of host-parasite dynamics are being studied to understand where to look for and how to manage emerging human diseases (Leroy 2005; Benelli 2018). Previous research has used the Global Mammal Parasite Database (GMPD) to look at host breadth—the number and diversity of species a pathogen can infect—for various groups of parasites, e.g. helminths, arthropods, fungi, etc., from a host-centric perspective (Stephens et al. 2017; Park et …

Ensemble Modeling Of Auditory Streaming Reveals Potential Sources Of Bistability Across The Perceptual Hierarchy, David F. Little, Joel S. Snyder, Mounya Elhilali

Psychology Faculty Research

Perceptual bistability—the spontaneous, irregular fluctuation of perception between two interpretations of a stimulus—occurs when observing a large variety of ambiguous stimulus configurations. This phenomenon has the potential to serve as a tool for, among other things, understanding how function varies across individuals due to the large individual differences that manifest during perceptual bistability. Yet it remains difficult to interpret the functional processes at work, without knowing where bistability arises during perception. In this study we explore the hypothesis that bistability originates from multiple sources distributed across the perceptual hierarchy. We develop a hierarchical model of auditory processing comprised of three …

Dugesia Japonica Is The Best Suited Of Three Planarian Species For High-Throughput Toxicology Screening, Danielle Ireland, Veronica Bochenek , '22, Daniel Chaiken , '20, Christina Rabeler, Sumi Onoe , '21, Ameet Soni, Eva-Maria S. Collins

Biology Faculty Works

High-throughput screening (HTS) using new approach methods is revolutionizing toxicology. Asexual freshwater planarians are a promising invertebrate model for neurotoxicity HTS because their diverse behaviors can be used as quantitative readouts of neuronal function. Currently, three planarian species are commonly used in toxicology research: Dugesia japonica, Schmidtea mediterranea, and Girardia tigrina. However, only D. japonica has been demonstrated to be suitable for HTS. Here, we assess the two other species for HTS suitability by direct comparison with D. japonica. Through quantitative assessments of morphology and multiple behaviors, we assayed the effects of 4 common solvents (DMSO, …

Synthesis And Molecular Mechanics Study Of Platinum Triamine Complex With N-Acetyl-L-Methionine And Guanosine 5’Monophosphate, Nitin Tanajirao Katare

Masters Theses & Specialist Projects

Cisplatin and its analogues have been used and tested over decades for cancer treatment, but because of the serious side effects, it is important to find ways to overcome those side effect by synthesizing a novel platinum molecule. We have synthesized triamine complex and conducted its reaction with biomolecules such as 5’GMP and Methionine in the lab as well as conducted molecular mechanics (MM). MM methods are used for predicting and designing new structures and properties, and to model geometries of small molecules. MM and dynamics calculations have been used to study the 9 Ethylguanine and N-Ac-Lmethionine complexes with platinum …

On The Distribution Of Genetic Variation In Ecological Communities, Isaac Overcast

Dissertations, Theses, and Capstone Projects

Biodiversity in ecological communities is structured hierarchically across spatial and temporal scales. Many open questions remain as to how this structure accumulates. For example, what are the relative contributions of dispersal versus in situ speciation? Or, how important are stochastic drift versus deterministic processes? Up to this point, these questions have been investigated by isolated disciplines (e.g. macroecology, comparative phylogeography, macroevolution) using tools and data that tend to focus on only one axis of community scale data (e.g. phylogenies, relative abundances, and/or trait information). Yet we know that there are feedbacks among processes that respond on short, medium, and long …

Machine Learning Prediction Of Glioblastoma Patient One-Year Survival, Andrew Du '20, Warren Mcgee, Jane Y. Wu

Student Publications & Research

Glioblastoma (GBM) is a grade IV astrocytoma formed primarily from cancerous astrocytes and sustained by intense angiogenesis. GBM often causes non-specific symptoms, creating difficulty for diagnosis. This study aimed to utilize machine learning techniques to provide an accurate one-year survival prognosis for GBM patients using clinical and genomic data from the Chinese Glioma Genome Atlas. Logistic regression (LR), support vector machines (SVM), random forest (RF), and ensemble models were used to identify and select predictors for GBM survival and to classify patients into those with an overall survival (OS) of less than one year and one year or greater. With …

Mathematical Models Of Cellular Signaling And Supramolecular Self-Assembly, Pratip Rana

Theses and Dissertations

Synthetic biologists endeavor to predict how the increasing complexity of multi-step signaling cascades impacts the fidelity of molecular signaling, whereby cellular state information is often transmitted with proteins diffusing by a pseudo-one-dimensional stochastic process. We address this problem by using a one-dimensional drift-diffusion model to derive an approximate lower bound on the degree of facilitation needed to achieve single-bit informational efficiency in signaling cascades as a function of their length. We find that a universal curve of the Shannon-Hartley form describes the information transmitted by a signaling chain of arbitrary length and depends upon only a small number of physically …

The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio

Graduate Theses, Dissertations, and Problem Reports (ETD)

The acquisition of microbial partners is a strategy used by a diverse group of arthropods to overcome ecological barriers that might normally make certain niches uninhabitable. The unique phylogenetic opportunities attainable from the natural experiment of the Sodalis-allied clade allow for better understanding of how molecular structures evolve through time. Here, we focus on the evolution of the flagellar synthesis pathway, due to its complexity and ability to diverge in response to ecological pressures. We used this molecular pathway and natural experiment to show that normal evolutionary outcomes associated with symbiosis (i.e., genome reduction) do not explain the predicted conservation …

Evaluation Of The Performance Of Probabilistic Genotyping Software On Complex Mixture Samples, Kristen Newland

Graduate Theses, Dissertations, and Problem Reports (ETD)

Probabilistic genotyping systems use sophisticated algorithms to aid DNA analysts with complex mixture interpretation. These systems are used to generate a likelihood ration (LR) which is used to provide the analyst with the statistical weight of the match between an evidence profile and a known contributor. Complex mixtures occur from samples consisting of more than two contributors and samples that have experienced degradation or consist of low template quantity.

This study was performed to compare the performance of three mixture analysis software tools on the same set of samples to determine the capabilities of each software, false inclusions, and false …

A Transcriptomic Exploration Of Hawaiian Drosophilid Development And Evolution, Madeline M. Chenevert

LSU New Orleans Theses and Dissertations

One in four known species of fruit flies inhabit the Hawaiian Islands. From a small number of colonizing flies, a wide range of species evolved, some of which managed to reverse-colonize other continental environments. In order to explore the developmental pathways, which separate the Hawaiian Drosophila proper and the Scaptomyza group that contains reverse-colonized species, the transcriptomes of two better-known species in each group, Scaptomyza anomala and Drosophila grimshawi, were analyzed to find changes in gene expression between the two groups. This study describes a novel transcriptome for S. anomala studies as well as unusual changes in gene expression …

Chasing The Genetics Of Ascites In Broilers Using Whole Genome Resequencing, Alia Parveen

Graduate Theses and Dissertations

We are using whole genome resequencing to identify chromosomal regions associated with resistance or susceptibility to ascites, a form of pulmonary hypertension syndrome, meat-type chickens. Previous Genome Wide Association Studies (GWAS) based on Single Nucleotide Polymorphisms (SNPs) have identified regions on chromosomes 2, 9 and Z. Despite several GWAS and further genotyping, there are no reliable or potential markers for ascites phenotype. We have completed screening of Copy Number Variations (CNVs) and Single Nucleotide Polymorphisms in ascites resistant and susceptible birds from the relaxed, REL, line derived from a commercial elite broiler line. DNA samples from resistant and susceptible birds …

Deepep: A Deep Learning Framework For Identifying Essential Proteins, Min Zeng, Min Li, Fang-Xiang Wu, Yaohang Li, Yi Pan

Computer Science Faculty Publications

Background: Essential proteins are crucial for cellular life and thus, identification of essential proteins is an important topic and a challenging problem for researchers. Recently lots of computational approaches have been proposed to handle this problem. However, traditional centrality methods cannot fully represent the topological features of biological networks. In addition, identifying essential proteins is an imbalanced learning problem; but few current shallow machine learning-based methods are designed to handle the imbalanced characteristics. Results: We develop DeepEP based on a deep learning framework that uses the node2vec technique, multi-scale convolutional neural networks and a sampling technique to identify essential proteins. …

Overlap Matrix Completion For Predicting Drug-Associated Indications, Menhyun Yang, Huimin Luo, Yaohang Li, Fang-Xiang Wu, Jianxin Wang

Computer Science Faculty Publications

Identification of potential drug-associated indications is critical for either approved or novel drugs in drug repositioning. Current computational methods based on drug similarity and disease similarity have been developed to predict drug-disease associations. When more reliable drug- or disease-related information becomes available and is integrated, the prediction precision can be continuously improved. However, it is a challenging problem to effectively incorporate multiple types of prior information, representing different characteristics of drugs and diseases, to identify promising drug-disease associations. In this study, we propose an overlap matrix completion (OMC) for bilayer networks (OMC2) and tri-layer networks (OMC3) to predict potential drug-associated …

Characterization And Amplification Of Retrotransposable Elements Platy-1 And Alu In The Cebidae Lineage Of Platyrrhine Primates, Jessica Storer

LSU Doctoral Dissertations

Alu mobile elements are much more than “junk DNA”. Inherent properties such as high copy number, small ~300 bp size, and their nearly homoplasy-free nature make these elements particularly useful in resolving primate phylogenies. In addition, shared sequence features and identity with the Alu element allow for discovery of new SINE retrotransposons, such as the Platyrrhine-limited Platy-1 element. Building on previous research of subfamily analysis, the Platy-1 and Alu elements can be used not only to explore the controversial New World monkey (NWM) phylogeny, but also the mode and tempo of their amplification in different primate genera and species.

Chapter …

Sdrap: An Annotation Pipeline For Highly Scrambled Genomes, Jasper Braun

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Network Structure And Dynamics Of Biological Systems, Deena R. Schmidt

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Loop Homology Of Bi-Secondary Structures, Andrei Bura

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …