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

芸苔目植物（包括大约4550种模式植物拟南芥和许多经济上重要的作物物种）的进化关系目前知之甚少。在进化的背景下，需要了解这些关系来解释丰富的基因组、发育和生理数据。本研究将利用核、线粒体和叶绿体基因组中编码的数百个位点来解决芸苔目内的系统发育关系。此外，该项目将研究多样化率和每个基因组区室（即核基因组和细胞器基因组）的进化——包括基因组大小、基因含量（如基因丢失和复制、新基因功能）和基因组结构。栽培和野生芸苔属植物具有许多对作物改良具有巨大价值的新性状和化学成分，包括生物抗性（如昆虫、真菌和线虫）和非生物抗逆性（如干旱、冷冻和重金属）。此外，这种植物群共享对人类健康有益的新化学物质，包括治疗心血管疾病和高血压。这项研究将增强我们对哪些物种共享这些有益的新生物化学和特征的理解，并描述潜在的生物合成途径。最终，这一框架将使这些性状成为制药和改良作物的目标。

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.