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The Hepatic Immunological Pattern Shaped By Dominant-Subdominant Cellular Interactions Creates A Collective Function Beyond The Function Of Each Cellular Constituent To Orchestrate Progression Of Hepatocellular Carcinoma, Nicholas J. Koelsch

Theses and Dissertations

Abundance of data on the role of inflammatory immune responses in the progression or inhibition of hepatocellular carcinoma (HCC) has failed to offer a curative immunotherapy for HCC. This is largely because of taking reductionist approaches and missing the collective function of the hepatic immune system by focusing on specific immune cell types. To this end, we propose that focusing on the dominant-subdominant patterns of the immune cells would allow understanding of the mechanism by which a collective immune function emerges. To identify the collective immune function through a systems immunology perspective, we performed high-throughput analysis of snRNAseq data collected …

Bioinformatic Pipeline For Determining Terminal Repeats In The Human Cytomegalovirus Genome Assembled With Pacbio Long Read Sequences, Ahmed Al Qaffas

Theses and Dissertations

Human Cytomegalovirus (HCMV) is a member of the betaherpesvirinae subfamily of the Herpesvirus family. HCMV infection is common among adults worldwide, with an estimated seroprevalence of 66 to 95%, depending on the geographic region (Zuhair et al., 2019). Although most of the virus genomic content has been studied extensively, the terminal repeating region sequences remain understudied. Two main challenges hindered the study of the region: a) limitations of sequencing technologies; and b) misassembly of the repeats due to its complex nature. Here I show a novel bioinformatics pipeline that takes advantage of PacBio's long reads to resolve the challenges mentioned …

Computational Analysis And Prediction Of Intrinsic Disorder And Intrinsic Disorder Functions In Proteins, Akila I. Katuwawala

Theses and Dissertations

COMPUTATIONAL ANALYSIS AND PREDICTION OF INTRINSIC DISORDER AND INTRINSIC DISORDER FUNCTIONS IN PROTEINS

By Akila Imesha Katuwawala

A dissertation submitted in partial fulfillment of the requirements for the degree of Engineering, Doctor of Philosophy with a concentration in Computer Science at Virginia Commonwealth University.

Virginia Commonwealth University, 2021

Director: Lukasz Kurgan, Professor, Department of Computer Science

Proteins, as a fundamental class of biomolecules, have been studied from various perspectives over the past two centuries. The traditional notion is that proteins require fixed and stable three-dimensional structures to carry out biological functions. However, there is mounting evidence regarding a “special” class …

Role Of Clic4 And The Synaptic Transcriptome In The Behavioral And Molecular Neurobiology Of Ethanol, Rory M. Weston

Theses and Dissertations

Alcohol use disorder (AUD) is a prevalent neuropsychiatric disease with profound health, social, and economic consequences. With an estimated 50% heritability, identifying genes that engender risk and contribute to the underlying neurobiological mechanisms represents an important first step in developing effective treatments. Gene expression studies are an important source of candidate genes for studying AUD, providing windows into the molecular machinery engaged by the brain in response to ethanol. Published studies have identified chloride intracellular channel 4 (Clic4) as an ethanol-regulated gene in brain capable of modulating sensitivity to sedation in multiple species. The functions of Clic4 are …

Evaluating Predixcan’S Ability To Predict Differential Expression Between Alcoholics And Non-Alcoholics, John E. Drake Jr

Theses and Dissertations

PrediXcan is a recent software for the imputation of gene expression from genotype data alone. Using an overlapping set of transcriptome datasets from postmortem brain tissues of donors with alcohol use disorder and neurotypical controls, which were generated by two different platforms (e.g., Arraystar and Affymetrix), and an additional unrelated transcriptome dataset from lung tissue, we sought to evaluate PrediXcan’s ability to impute gene expression and identify differentially expressed genes. From the Arraystar platform, 1.3% of matched genes between the measured and imputed expression had a Pearson correlation ≥ 0.5. Our attempt to replicate this finding using the expression data …

Discovering Driver Mutations In Biological Data, Yahya Bokhari

Theses and Dissertations

Background

Somatic mutations accumulate in human cells throughout life. Some may have no adverse consequences, but some of them may lead to cancer. A cancer genome is typically unstable, and thus more mutations can accumulate in the DNA of cancer cells. An ongoing problem is to figure out which mutations are drivers - play a role in oncogenesis, and which are passengers - do not play a role. One way of addressing this question is through inspection of somatic mutations in DNA of cancer samples from a cohort of patients and detection of patterns that differentiate driver from passenger mutations. …

Network Analytics For The Mirna Regulome And Mirna-Disease Interactions, Joseph Jayakar Nalluri

Theses and Dissertations

miRNAs are non-coding RNAs of approx. 22 nucleotides in length that inhibit gene expression at the post-transcriptional level. By virtue of this gene regulation mechanism, miRNAs play a critical role in several biological processes and patho-physiological conditions, including cancers. miRNA behavior is a result of a multi-level complex interaction network involving miRNA-mRNA, TF-miRNA-gene, and miRNA-chemical interactions; hence the precise patterns through which a miRNA regulates a certain disease(s) are still elusive. Herein, I have developed an integrative genomics methods/pipeline to (i) build a miRNA regulomics and data analytics repository, (ii) create/model these interactions into networks and use optimization techniques, motif …

A Pipeline For Creation Of Genome-Scale Metabolic Reconstructions, Shaun W. Norris

Theses and Dissertations

The decreasing costs of next generation sequencing technologies and the increasing speeds at which they work have lead to an abundance of 'omic datasets. The need for tools and methods to analyze, annotate, and model these datasets to better understand biological systems is growing. Here we present a novel software pipeline to reconstruct the metabolic model of an organism in silico starting from its genome sequence and a novel compilation of biological databases to better serve the generation of metabolic models. We validate these methods using five Gardnerella vaginalis strains and compare the gene annotation results to NCBI and the …

Prediction Of Protein-Protein Interactions In Escherichia Coli From Experimental Data In Treponema Pallidum, Marco A. Abreu

Theses and Dissertations

Protein – Protein interactions (PPIs) are thought to be conserved between species, although this has not been systematically investigated. This problem was explored in Escherichia coli from experimental data in Treponema pallidum by predicting PPIs, focusing on protein domains of little or unknown function. The comparison of T. pallidum to a model organism such as E. coli can not only reveal additional data about T. pallidum but also reveals how E. coli is similar to this distantly related, obligate parasite. A set of novel T. pallidum interactions, enriched for proteins of unknown function, were the basis of over 23,000 predicted …

Inferring Gene Regulatory Networks From Expression Data Using Ensemble Methods, Janusz Slawek

Theses and Dissertations

High-throughput technologies for measuring gene expression made inferring of the genome-wide Gene Regulatory Networks an active field of research. Reverse-engineering of systems of transcriptional regulations became an important challenge in molecular and computational biology. Because such systems model dependencies between genes, they are important in understanding of cell behavior, and can potentially turn observed expression data into the new biological knowledge and practical applications. In this dissertation we introduce a set of algorithms, which infer networks of transcriptional regulations from variety of expression profiles with superior accuracy compared to the state-of-the-art techniques. The proposed methods make use of ensembles of …

Detecting And Correcting Batch Effects In High-Throughput Genomic Experiments, Sarah Reese

Theses and Dissertations

Batch effects are due to probe-specific systematic variation between groups of samples (batches) resulting from experimental features that are not of biological interest. Principal components analysis (PCA) is commonly used as a visual tool to determine whether batch effects exist after applying a global normalization method. However, PCA yields linear combinations of the variables that contribute maximum variance and thus will not necessarily detect batch effects if they are not the largest source of variability in the data. We present an extension of principal components analysis to quantify the existence of batch effects, called guided PCA (gPCA). We describe a …

A Novel Method To Detect Functional Subgraphs In Biomolecular Networks, Sterling Thomas

Theses and Dissertations

Several biomolecular pathways governing the control of cellular processes have been discovered over the last several years. Additionally, advances resulting from combining these pathways into networks have produced new insights into the complex behaviors observed in cell function assays. Unfortunately, identification of important subnetworks, or “motifs”, in these networks has been slower in development. This study focused on identifying important network motifs and their rate of occurrence in two different biomolecular networks. The two networks evaluated for this study represented both ends of the spectrum of interaction knowledge by comparing a well defined network (apoptosis) with and poorly studied network …

Bioinformatic Analysis Of A Mammalian Bip Gene For Insertion Into Green Algae And Comparison Of Its Possible Effects On The Synthesis Of A Mammalian Antibody, Katrina Ghazanfar

Theses and Dissertations

This dissertation describes a study utilizing bioinformatics to analyze homologues of a molecular chaperone, glucose-regulated protein 78 (grp 78), also known as BiP. The selected homologous proteins originate from organisms of infinitely diverse genera. Comparisons of protein sequence yielded the first clues of a common ancestry among these proteins. Furthermore, protein molecular weights, isoelectric points, N-terminal amino acids and half-lives of a known homolog and a non-homologous protein were examined. Additionally, electroporation, a state-of-the-art plasmid insertion technique, was explored using Chlamydomonas reinhardtii, a green alga, as the recipient of a parent plasmid, pSP124S. Distinctive hypertonic solutions and three separate field …