Evolutionary dynamics of gene and genome duplications in plants
Abstract
My research examined the evolution of gene and genome duplications across plants. Gene and whole genome duplications represent two distinct processes resulting in the in either the doubling of a gene (or chromosomal region) or the doubling of the entire genome. Whole genome duplications, polyploidy, occur through the break down in meiosis and either the doubling of chromosome numbers through hybridization events, allotetraploidy, or through chromosomal non-disjunction leading to autotetraploidy. In contrast individual gene duplications occur as result of errors in DNA repair, chromosomal rearrangements due during recombination, or retrotransposition events. The doubling of genetic material, either through polyploidy or small-scale gene duplications, plays an important role in the formation of novel adaptive genetic and biochemical pathways and the evolution of genome architecture. Green plants, especially flowering plants, have long been known to undergo polyploidization and high rates of individual gene duplication and retention. Given the dynamic nature of green plant genome biology they make an ideal system with which to examine the evolution of gene and whole genome duplications. I examined 20 species of plants including 8 algae from the Chlorophyta, 10 land based plants from Streptophyta, and 1 each from Glaucophyta and Rhodophyta. I used a combination of pairwise sequence comparisons and population and intraspecific comparisons of molecular evolution to understand the role of gene and whole genome duplication events on genome evolution. To accomplish this research I used a bioinformatic pipeline to identify duplication events within each plant species and allowed me to find genes undergoing adaptive evolution.
Degree
Ph.D.
Advisors
Zanis, Purdue University.
Subject Area
Plant biology|Genetics|Evolution and Development|Bioinformatics
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