Genomics Commons^™

Improving The Phylogenetic Understanding Of The Genus Juniperus, Therese Balkenbush

All Master's Theses

Juniperus is a species-rich and geographically widespread genus of coniferous trees and shrubs. The genus is relatively recently diverged, and has experienced periods of rapid diversification. Recent phylogenetic investigations by others have compared DNA from selected regions of the chloroplast, but the resulting topologies conflict, and some relationships remain unresolved. Their relatively small data sets failed to capture sufficient variation to resolve events of rapid diversification in these closely related taxa. This study provides increased resolution and support by generating a plastome-scale phylogeny for 28 Juniperus species, revealing previously unresolved relationships at both deep and shallow nodes. One-third of the …

Software Development For Genome Sequence Analysis, David Farr

Symposium Of University Research and Creative Expression (SOURCE)

The cost of genome sequencing has decreased rapidly, expanding availability for many biological applications (Muir 2016). For example, researchers can now obtain genome sequences from multiple populations under different types of selection. Comparison of these sequences allows for identification of chromosome regions and specific genes associated with adaptive evolution (Kelly 2013). As an increasing number of researchers engage in this type of inquiry, many have created in-house computer scripts to analyze the raw sequence data (e.g., Kelly 2013), creating a gap in both continuity and standardization.

Using a test dataset and preliminary results from an ongoing artificial selection experiment in …

Resolving Gnetum Evolutionary History, Angela Mcfadden

All Master's Theses

Gnetum are non-flowering seed plants of the tropics, indigenous to South America, Africa, and Asia. This group of about 40 species is fascinating to botanists because it shares distinctive morphological characteristics with flowering plants, such as broad leaves, woody stems, and flower-like strobili. There are still questions surrounding the relationships within the genus of Gnetum. With that in mind, I focused my work on generating phylogenetic hypotheses, using two molecular data sets: a concatenation of over 60 different chloroplast genes (66,815 base pairs), and the whole chloroplast genome (128,772 base pairs). This allowed me to compare the two phylogenies …

Mendelian Breeding Units Versus Standard Sampling Strategies: Mitochondrial Dna Variation In Southwest Sardinia, Daria Sanna, Joseph G. Lorenz

All Faculty Scholarship for the College of the Sciences

We report a sampling strategy based on Mendelian Breeding Units (MBUs), representing an interbreeding group of individuals sharing a common gene pool. The identification of MBUs is crucial for case-control experimental design in association studies. The aim of this work was to evaluate the possible existence of bias in terms of genetic variability and haplogroup frequencies in the MBU sample, due to severe sample selection. In order to reach this goal, the MBU sampling strategy was compared to a standard selection of individuals according to their surname and place of birth. We analysed mitochondrial DNA variation (first hypervariable segment and …

Implications Of The Plastid Genome Sequence Of Typha (Typhaceae, Poales) For Understanding Genome Evolution In Poaceae, Mary M. Guisinger, Timothy W. Chumley, Jennifer V. Kuehl, Jeffrey L. Boore, Robert K. Jansen

All Faculty Scholarship for the College of the Sciences

Plastid genomes of the grasses (Poaceae) are unusual in their organization and rates of sequence evolution. There has been a recent surge in the availability of grass plastid genome sequences, but a comprehensive comparative analysis of genome evolution has not been performed that includes any related families in the Poales. We report on the plastid genome of Typha latifolia, the first non-grass Poales sequenced to date, and we present comparisons of genome organization and sequence evolution within Poales. Our results confirm that grass plastid genomes exhibit acceleration in both genomic rearrangements and nucleotide substitutions. Poaceae have multiple structural rearrangements, including …

Comparative Chloroplast Genomics: Analyses Including New Sequences From The Angiosperms Nuphar Advena And Ranunculus Macranthus, Linda A. Raubeson, Rhiannon Peery, Timothy W. Chumley, Chris Dziubek, H. Matthew Fourcade, Jeffrey L. Boore, Robert K. Jansen

All Faculty Scholarship for the College of the Sciences

Background

The number of completely sequenced plastid genomes available is growing rapidly. This array of sequences presents new opportunities to perform comparative analyses. In comparative studies, it is often useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the genomes reported here: Nuphar advena (from a basal-most lineage) and Ranunculus macranthus (a basal eudicot). We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages) to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution …

Methods For Obtaining And Analyzing Whole Chloroplast Genome Sequences, Robert K. Jansen, Linda A. Raubeson, Jeffrey L. Boore, Claude W. Depamphilis, Timothy W. Chumley, Rosemarie C. Haberle, Stacia K. Wyman, Andrew J. Alverson, Riannon Peery, Sallie J. Herman, H. Matthew Fourcade, Jennifer V. Kuehl, Joel R. Mcneal, James Leebens-Mack, Liying Cui

All Faculty Scholarship for the College of the Sciences

During the past decade there has been a rapid increase in our understanding of plastid genome organization and evolution due to the availability of many new completely sequenced genomes. Currently there are 43 complete genomes published and ongoing projects are likely to increase this sampling to nearly 200 genomes during the next five years. Several groups of researchers including ours have been developing new techniques for gathering and analyzing entire plastid genome sequences and details of these developments are summarized in this chapter. The most important recent developments that enhance our ability to generate whole chloroplast genome sequences involve the …

Chloroplast Dna Rearrangements In Campanulaceae: Phylogenetic Utility Of Highly Rearranged Genomes, Mary E. Cosner, Linda A. Raubeson, Robert K. Jansen

All Faculty Scholarship for the College of the Sciences

Background

The Campanulaceae (the "hare bell" or "bellflower" family) is a derived angiosperm family comprised of about 600 species treated in 35 to 55 genera. Taxonomic treatments vary widely and little phylogenetic work has been done in the family. Gene order in the chloroplast genome usually varies little among vascular plants. However, chloroplast genomes of Campanulaceae represent an exception and phylogenetic analyses solely based on chloroplast rearrangement characters support a reasonably well-resolved tree.

Results

Chloroplast DNA physical maps were constructed for eighteen representatives of the family. So many gene order changes have occurred among the genomes that characterizing individual mutational …