Genetics and Genomics Commons^™

Illuminating The Drivers Of Genomic Diversification In Lamprologine Cichlids Of The Lower Congo River, Naoko P. Kurata

Dissertations, Theses, and Capstone Projects

Freshwater fishes are extraordinarily diverse, considering their available habitats represent a tiny proportion of the earth’s surface. Rivers connect heterogeneous habitats in a linear form and provide excellent simplified models to understand how aquatic biodiversity evolves. In particular, the lower Congo River (LCR) in west Central Africa consists of a dynamic hydroscape exhibiting extraordinary aquatic biodiversity, endemicity, and morphological and ecological specialization. This system is thus an excellent natural laboratory for understanding complex speciation and population diversification processes. In my research, I explore various drivers of diversification, and adaptive evolution in rheophilic lamprologine cichlids endemic to the LCR, including Lamprologus …

Phylogenomic Discordance Suggests Polytomies Along The Backbone Of The Large Genus Solanum, Edeline Gagnon, Rebeccca Hilgenhof, Andrés Orejuela, Angela J. Mcdonnell, Gaurav Sablok, Xavier Aubriot, Leandro Giacomin, Yuri Gouvêa, Thamyris Bragionis, João Renato Stehmann, Lynn Bohs, Steven Dodsworth, Christopher T. Martine, Péter Poczai, Sandra Knapp, Tiina Särkinen

Faculty Journal Articles

Premise of the study

Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree of gene-tree discordance in Solanum, one of the largest flowering plant genera that includes the cultivated potato, tomato, and eggplant, as well as 24 minor crop plants.

Methods

A densely sampled species-level phylogeny of Solanum is built using unpublished and publicly available Sanger sequences comprising 60% of all accepted species (742 spp.) …

Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein

Theses and Dissertations

In this study I attempted to further resolve the population genetic structure in the Prothonotary Warbler (Protonotaria citrea), and conducted an outlier SNP analysis and exploratory gene ontology analysis to investigate potential ongoing natural selection in the species. This analysis of population structure confirms previous work by DeSaix et al. (2019), where weak population structure was observed between eastern sites along the Atlantic Coastal Plain, and western sites in the Mississippi Alluvial Valley, possibly due to a genetic discontinuity across the Appalachian Mountains. I conducted two forms of outlier SNP analyses, a principal component analysis (PCA)-based approach to identify SNPs …

A Genomic Analysis Of Bobcat Populations In North America With A Comparison To The Canada Lynx: An Assessment Of Local Adaptation To Unique Ecoregions And Phylogeography, Jennifer C. Broderick

Electronic Theses and Dissertations

Bobcats (Lynx rufus) are an ecologically and genetically diverse species with a large contiguous range throughout North America. The species not only has a wide array of phenotypic variation compared to other mammals, but shows marked adaptability across ecozones with differing ecological influences. It is these various selective pressures in distinctive parts of the continent that have likely led to localized adaptations within the bobcat metapopulations. The species is also marked by its ability to maintain connectivity and populations in anthropogenically developed areas, an advantage it has over other felids, including its close relative the Canada lynx ( …

Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer

Poisonous Plant Research (PPR)

Locoweeds are the most widespread poisonous plant problem in the world and have been reported in the Western United States since the 1800s, causing tremendous losses in livestock. Consumption of locoweeds by grazing animals stimulates the neurological disease, locoism, characterized by weight loss, ataxia, and lack of muscular coordination. The name locoweed is used for Astragalus and Oxytropis species known to contain swainsonine, the toxic principle produced by the plant endophytic fungus Undifilum. Astragalus includes 2,500-3,000 species and many varieties that have almost identical morphological characteristics that overlap among species, leading to improper identification. Therefore, the aim of this study …

De-Coding The Impact Of Evolved Changes In Gene Expression And Cellular Phenotype On Primate Evolution, Trisha Zintel

Doctoral Dissertations

The goal of the dissertation work outlined here was to investigate the influence of proximal processes contributing to evolutionary differences in phenotypes among primate species. There are numerous previous comparative analyses of gene expression between primate brain regions. However, primate brain tissue samples are relatively rare, and my results have contributed to the pre-existing data on more well-studied primates (i.e. humans, chimpanzees, macaques, marmosets) as well as produced information on more rarely-studied primates (i.e. patas monkey, siamang, spider monkey). Additionally, the primary visual cortex has not previously been as extensively studied at the level of gene expression as other brain …

Computational Analysis Of Large-Scale Trends And Dynamics In Eukaryotic Protein Family Evolution, Joseph Boehm Ahrens

FIU Electronic Theses and Dissertations

The myriad protein-coding genes found in present-day eukaryotes arose from a combination of speciation and gene duplication events, spanning more than one billion years of evolution. Notably, as these proteins evolved, the individual residues at each site in their amino acid sequences were replaced at markedly different rates. The relationship between protein structure, protein function, and site-specific rates of amino acid replacement is a topic of ongoing research. Additionally, there is much interest in the different evolutionary constraints imposed on sequences related by speciation (orthologs) versus sequences related by gene duplication (paralogs). A principal aim of this dissertation is to …

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.

Population Structure And Connectivity Of A Groundwater Crustacean Across Northwestern Montana Aquifers, Megan N. Ritter

Master’s Theses

Floodplain aquifer systems are diverse and heterogenous ecosystems that serve many ecological functions, including habitat provision to a range of groundwater species. The Flathead River system of northwestern Montana is home to many floodplain aquifers of great ecological importance to the region. The basic biology, population structure, and dispersal patterns of obligate groundwater organisms that reside within the aquifers of the Flathead are still largely unknown. In this study, we investigate the population structure of one such taxon, an undescribed species of the amphipod genus Stygobromus. For our low-coverage RADseq dataset, we tested the suitability of three different analysis …

Evolution Of Voltage-Gated Ion Channels, Kevin Gregory Bennett, Kevin Bennett

Master of Science in Integrative Biology Theses

Voltage-gated Ion Channels (VICs) form a superfamily of energy-independent membrane transporters that facilitate the transfer of charged sodium, calcium, and potassium ions across the cell membrane (Hodgkin & Huxley 1952). The channels contain a selective ion-conducting pore along with several other structural and gating features that come together to form a functional hetero- or homotetramer. A comprehensive phylogenetic study of all available proteins aimed at finding unknown distribution and illuminating evolutionary paths would be immensely useful in understanding relationships of structure, function, and organismal distribution. This phylogenetic analysis of VICs will be immensely useful in characterizing functional and structural distribution, …

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. …

Impacts Of Genome And Nuclear Architecture On Molecular Evolution In Eukaryotes, Xyrus Maurer-Alcalá

Doctoral Dissertations

The traditional view of genomes suggests that they are static entities changing slowly in sequence and structure through time (e.g. evolving over geological time-scales). This outdated view has been challenged as our understanding of the dynamic nature of genomes has increased. Changes in DNA content (i.e. polyploidy) are common to specific life-cycle stages in a variety of eukaryotes, as are changes in genome content itself. These dramatic genomic changes include chromosomal deletions (i.e. paternal chromosome deletion in insects; Goday and Esteban 2001; Ross, et al. 2010), developmentally regulated genome rearrangements (e.g. the V(D)J system in adaptive immunity in mammals; Schatz …

Robust Algorithms For Detecting Hidden Structure In Biological Data, Roman Sloutsky

Arts & Sciences Electronic Theses and Dissertations

Biological data, such as molecular abundance measurements and protein

sequences, harbor complex hidden structure that reflects its underlying

biological mechanisms. For example, high-throughput abundance measurements

provide a snapshot the global state of a living cell, while homologous

protein sequences encode the residue-level logic of the proteins' function

and provide a snapshot of the evolutionary trajectory of the protein family.

In this work I describe algorithmic approaches and analysis software I

developed for uncovering hidden structure in both kinds of data.

Clustering is an unsurpervised machine learning technique commonly used

to map the structure of data collected in high-throughput experiments,

such …

Using Phylogenetically-Informed Annotation (Pia) To Search For Light-Interacting Genes In Transcriptomes From Non-Model Organisms, Daniel I. Speiser, M. Sabrina Pankey, Alexander K. Zaharoff, Barbara A. Battelle, Heather D. Bracken-Grissom, Jesse W. Breinholt, Seth M. Bybee, Thomas W. Cronin, Anders Garm, Annie R. Lindgren, Nipam H. Patel, Megan L. Porter, Meredith E. Protas, Anja S. Rivera, Jeanne M. Serb, Kirk S. Zigler, Keith A. Crandall, Todd H. Oakley

Meredith Protas

Background: Tools for high throughput sequencing and de novo assembly make the analysis of transcriptomes (i.e. the suite of genes expressed in a tissue) feasible for almost any organism. Yet a challenge for biologists is that it can be difficult to assign identities to gene sequences, especially from non-model organisms. Phylogenetic analyses are one useful method for assigning identities to these sequences, but such methods tend to be time-consuming because of the need to re-calculate trees for every gene of interest and each time a new data set is analyzed. In response, we employed existing tools for phylogenetic analysis to …

Incremental Phylogenetics By Repeated Insertions: An Evolutionary Tree Algorithm, Peter Revesz, Zhiqiang Li

School of Computing: Faculty Publications

We introduce the idea of constructing hypothetical evolutionary trees using an incremental algorithm that inserts species one-by-one into the current evolutionary tree. The method of incremental phylogenetics by repeated insertions lead to an algorithm that can be used on DNA, RNA and amino acid sequences. According to experimental results on both synthetic and biological data, the new algorithm generates more accurate evolutionary trees than the UPGMA and the Neighbor Joining algorithms.

Computational Identification Of Terpene Synthase Genes And Their Evolutionary Analysis, Qidong Jia

Doctoral Dissertations

Terpenoids, the largest and most structurally and functionally diverse class of natural compounds on earth, are mostly synthesized by plants to be involved in various plant environment interactions. Some terpenoids are classified as primary metabolites essential for plant growth and development. Terpene synthases (TPSs), the key enzymes for terpenoid biosynthesis, are the major determinant of the tremendous diversity of terpenoid carbon skeletons. The TPS genes represent a mid-size family of about 30-100 functional genes in almost all major sequenced plant genomes. TPSs are also found in fungi and bacteria, but microbial TPS genes share low levels of sequence similarity and …

A Mitochondrial Dna-Based Computational Model Of The Spread Of Human Populations, Peter Revesz

School of Computing: Faculty Publications

This paper presents a mitochondrial DNA-based computational model of the spread of human populations. The computation model is based on a new measure of the relatedness of two populations that may be both heterogeneous in terms of their set of mtDNA haplogroups. The measure gives an exponentially increasing weight for the similarity of two haplogroups with the number of levels shared in the mtDNA classification tree. In an experiment, the computational model is applied to the study of the relatedness of seven human populations ranging from the Neolithic through the Bronze Age to the present. The human populations included in …

Mutations Of Adjacent Amino Acid Pairs Are Not Always Independent, Jyotsna Ramanan, Peter Revesz

CSE Conference and Workshop Papers

Evolutionary studies usually assume that the genetic mutations are independent of each other. This paper tests the independence hypothesis for genetic mutations with regard to protein coding regions. According to the new experimental results the independence assumption generally holds, but there are certain exceptions. In particular, the coding regions that represent two adjacent amino acids seem to change in ways that sometimes deviate significantly from the expected theoretical probability under the independence assumption.

An Exploration Of The Phylogenetic Placement Of Recently Discovered Ultrasmall Archaeal Lineages, Jeffrey M. O'Brien

Honors Scholar Theses

In recent years, several new clades within the domain Achaea have been discovered. This is due in part to microbiological sampling of novel environments, and the increasing ability to detect and sequence uncultivable organisms through metagenomic analysis. These organisms share certain features, such as small cell size and streamlined genomes. Reduction in genome size can present difficulties to phylogenetic reconstruction programs. Since there is less genetic data to work with, these organisms often have missing genes in concatenated multiple sequence alignments. Evolutionary Biologists have not reached a consensus on the placement of these lineages in the archaeal evolutionary tree. There …

Mysteries Of The Trypanosomatid Maxicircles: Characterization Of The Maxicircle Genomes And The Evolution Of Rna Editing In The Order Kinetoplastida, Preethi Ranganathan Iyengar

Theses and Dissertations

The trypanosomatid protists belonging to Order Kinetoplastida are some of the most successful parasites ever known to mankind. Their extreme physiological diversity and adaptability to different environmental conditions and host systems make them some of the most widespread parasites, causing deadly diseases in humans and other vertebrates.

This project focuses on their unique mitochondrion, called the kinetoplast, and more specifically involves the characterization of a part of their mitochondrial DNA (also called kinetoplast DNA or kDNA), the maxicircles, which are functional homologs of eukaryotic mitochondrial DNA in the kinetoplastid protists. We have sequenced and characterized the maxicircle genomes of 20 …

An Examination Of The Phylogenetic Diversity Of Green Algae (Chlorophyceae) That Symbiose With Spotted Salamanders (Ambystoma Maculatum) In The Egg Stage., Crystal Xue

Honors Scholar Theses

In 1909, the species Oophila amblystomatis Lambert ex Wille was described for green algae that symbiose with salamanders in the egg stage (Wille). There are two hypotheses about the source of algae: 1) that algae enter from the surrounding water once the egg clutch is laid in a pond, and 2) that they are acquired from the maternal reproductive tract. We developed a third hypothesis developed to account for the salamander reproductive cycle. Male salamanders lay spermatophores, which are protein-filled capsules, on plant matter in and around ponds. Spermatophores are exposed to the environment before use by females in internal …

Using Phylogenetically-Informed Annotation (Pia) To Search For Light-Interacting Genes In Transcriptomes From Non-Model Organisms, Daniel I. Speiser, M. Sabrina Pankey, Alexander K. Zaharoff, Barbara A. Battelle, Heather D. Bracken-Grissom, Jesse W. Breinholt, Seth M. Bybee, Thomas W. Cronin, Anders Garm, Annie R. Lindgren, Nipam H. Patel, Megan L. Porter, Meredith E. Protas, Anja S. Rivera, Jeanne M. Serb, Kirk S. Zigler, Keith A. Crandall, Todd H. Oakley

Collected Faculty and Staff Scholarship

Background: Tools for high throughput sequencing and de novo assembly make the analysis of transcriptomes (i.e. the suite of genes expressed in a tissue) feasible for almost any organism. Yet a challenge for biologists is that it can be difficult to assign identities to gene sequences, especially from non-model organisms. Phylogenetic analyses are one useful method for assigning identities to these sequences, but such methods tend to be time-consuming because of the need to re-calculate trees for every gene of interest and each time a new data set is analyzed. In response, we employed existing tools for phylogenetic analysis to …

Comparative Genomics Of Closely Related Salmonella Enterica Serovar Typhi Strains Reveals Genome Dynamics And The Acquisition Of Novel Pathogenic Elements, Kien-Pong Yap

Kien-Pong Yap

Background Typhoid fever is an infectious disease of global importance that is caused by Salmonella enterica subsp. enterica serovar Typhi (S. Typhi). This disease causes an estimated 200,000 deaths per year and remains a serious global health threat. S. Typhi is strictly a human pathogen, and some recovered individuals become long-term carriers who continue to shed the bacteria in their faeces, thus becoming main reservoirs of infection.

Results A comparative genomics analysis combined with a phylogenomic analysis revealed that the strains from the outbreak and carrier were closely related with microvariations and possibly derived from a common ancestor. Additionally, the …

A Phylogenetic Analysis Of Armored Scale Insects, Based Upon Nuclear, Mitochondrial, And Endosymbiont Gene Sequences, Jeremy C. Andersen

Masters Theses 1911 - February 2014

Armored scale insects (Hemiptera: Diaspididae) are among the most invasive insects in the world. They have unusual genetic systems, including diverse types of paternal genome elimination (PGE) and parthenogenesis. Intimate relationships with their host plants and bacterial endosymbionts make them potentially important subjects for the study of co- evolution. Also, in some groups, the adult female never sheds the second instars cuticle, and remains within its confines, a habit referred to as the pupillarial habit. Here we expand upon recent phylogenetic work (Morse and Normark 2006) by analyzing a partitioned dataset including armored scale and endoysmbiont DNA from one hundred …