Abstract Detail

Phylogenomics

Thomas, Shawn [1], Pires, Chris [2].

Genome-enabled systematics in the tribe Brassiceae.

The tribe Brassiceae (~50 genera, ~250 species) is a monophyletic lineage within the Brassicaceae (Mustard) family. Evidence from previous studies confirm that the core Brassiceae shares an ancient hexaploidy and diverged from the rest of the Brassicaceae around 9-28mya. However, it is unknown if the ancient hexaploidy is shared only in the core Brassiceae or the whole tribe. Additionally there is some uncertainty with regards to dating this whole genome triplication as fossils in the Brassiceae and Brassicaceae are questionable. In this study, we will explore the polyploid origin and evolution in the tribe Brassiceae. We will use comparative genomics to understand these large-scale genome-level questions. The major limitation for answering this question in the past has been the cost to create highly contiguous genomes, but with lower sequencing costs and new long read technologies, this task has become more feasible both in monetary cost and computational time. In the core Brassiceae there are a large number of economically important crops (broccoli, cabbage, kale, canola, etc.) and this group has many reference genomes. Therefore we will focus on generating genomes and transcriptomes for the deeper lineages of Brassiceae to improve our phylogenetic sampling. Using genomic data for the tribe, we will identify single, duplicated and triplicated genes in the dataset and reconstruct the ancient hexaploid genome. Then to date the hexploidy, we will use more robust fossil calibrations in the Rosids, and publicly available transcriptome data in combination with data from our lab to construct a species tree and perform a divergence time analysis. Understanding the timing and placement of the Brassiceae whole genome triplication are crucial to further elucidate the evolutionary history of the tribe Brassiceae.

1 - University Of Missouri, Division Of Biological Sciences, 1201 Rollins Street, 311 Bond Life Sciences Center, Columbia, MO, 65211, United States
2 - University Of Missouri, 371 Bond Life Sciences Center, 1201 Rollins Street, Columbia, MO, 65211, United States

Keywords:
phylogenomics
genome evolution
Brassicaceae
divergence time estimation.

Presentation Type: Poster
Session: P3, Phylogenomics Posters
Location: Virtual/Virtual
Date: Wednesday, July 21st, 2021
Time: 5:00 PM(EDT)
Number: P3PL007
Abstract ID:493
Candidate for Awards:Phytochemical Best Poster Award