DISSERTATION RESEARCH: Systematics of the Order Brassicales and Family Brassicaceae, and comparative genomic analyses (nuclear and organellar genomes): a phylogenomic approach

University Of Missouri-Columbia, Columbia MO

Investigators

Abstract

The evolutionary relationships amongst species in the order Brassicales (which includes approximately 4550 species, the model plant species Arabidopsis thaliana, and many economically important crop species), are currently poorly known. Knowledge of these relationships is required to interpret the wealth of genomic, developmental, and physiological data available for this group within an evolutionary context. This study will resolve the phylogenetic relationships within the order Brassicales utilizing hundreds of loci encoded across the nuclear, mitochondrial, and chloroplast genomes. In addition, this project will investigate diversification rates and the evolution of each genome compartment (i.e. nuclear and organellar genomes) -- including genome size, gene content (e.g. gene loss and duplications, novel gene functions), and genome structure. Cultivated and wild Brassicales species possess numerous novel traits and chemistries with enormous value to crop improvement, including biotic resistances (e.g. insects, fungi, and nematodes) and abiotic stress tolerances (e.g. drought, freezing, and heavy metals). In addition, this plant group shares novel chemistries that are beneficial to human health, including treatments for cardiovascular disease and high blood pressure. This research will enhance our understanding of which species share these beneficial novel biochemistries and traits, and characterizing the underlying biosynthetic pathways. Ultimately, this framework will allow these traits to be targeted for pharmaceuticals and to improve crops.