Abstract Detail

Comparative Genomics/Transcriptomics

Chanderbali, Andre [1], Berger, Brent [2], Albert, Victor [3], Howarth, Dianella [4], Soltis, Douglas [5], Soltis, Pamela S. [1].

Genes, Genomes, and Gamma.

The most species-rich lineage of flowering plants, the Pentapetalae, exhibit enormous floral diversity. Yet, they share a highly conserved ground plan of “whorled-pentamery” - five-parted floral organs arranged in whorled phyllotaxis. By contrast, flowers of the earlier-diverging basal eudicot lineages exhibit marked fluidity in floral organ number and arrangement. Evolutionary changes in gene content and gene expression regulation also coincide with the origin of Pentapetalae. Importantly, an ancient whole-genome triplication – “gamma” – has enriched the genomes of Pentapetalae species with duplicate or triplicate copies of transcription factors regulating floral development. The molecular evolutionary consequences of “gamma” are therefore perhaps pivotal to Pentapetalae success, but its phylogenetic timing and mechanistic details are as yet not fully resolved. Our work provides the first insights into the genomes of representatives of the Buxales and Trochodendrales, which we identify as collective sisters to the core eudicots (Gunnerales plus Pentapetalae). These two new genomes are therefore pivotal to evolutionary inferences about the ancestral genomic context and evolutionary changes associated with the origin of the Pentapetalae. We also present phylogenomic analyses of gene and/or genomic duplications among all the major earlier-diverging basal eudicot lineages. Our comparative phylogenetic, phylogenomic, and genomic analyses provide new insights into the specific evolutionary changes that precede and coincide with the origin of the Pentapetalae - arguably one of the most important events during terrestrial plant evolution.

1 - University of Florida, Florida Museum of Natural History, 1659 Museum Road, Gainesville, FL, 32611, US
2 - St. John's University, 8000 Utopia Parkway, Queens, NY, 11439, United States
3 - Nanyang Technological University, Singapore
4 - St. John's University, Department Of Biological Sciences, St. Albert Hall Rm 257, 8000 Utopia Pkwy, Jamiaca, NY, 11439, United States
5 - Florida Museum of Natural History, University of Florida, 1659 Museum Road, Gainesville, Florida, 32611, United States

Keywords:
gamma
Pentapetalae
Buxales
Trochodendrales
paleohexaploidy
eudicots.

Presentation Type: Oral Paper
Session: 21, Comparative Genomics and Transcriptomics I
Location: 102/Mayo Civic Center
Date: Tuesday, July 24th, 2018
Time: 9:00 AM
Number: 21005
Abstract ID:752
Candidate for Awards:None