Abstract Detail

Development and Structure

Ye, Hanqi [1], Zhang, Jingbo [2], Chanderbali, Andre [3], Jin, Lingling [4], Xu, Qiaoji [5], Albert, Victor [6], Sankoff, David [7], Soltis, Pamela [8], Soltis, Douglas E. [9], Howarth, Dianella G. [10].

Using synteny network approaches to study the origin of the core eudicot whorled pentamerous flower.

One of the key questions in flowering plant evolution is the origin of the highly conserved whorled pentamerous flowers in core eudicots, in which the floral organs are arranged in concentric whorls. In contrast, basal eudicots have significant lability and variation in floral merosity and phyllotaxy. The origin of the core eudicots is associated with an ancient hexaploidy (gamma), which could have played an important role in the origin of the pentamerous flower, although a causal relationship is still speculative. We recently completed high-quality genome assemblies for two basal eudicot species, Buxus sinica and Tetracentron sinense. These datasets provide an opportunity to better understand how gamma may have influenced the genetic regulation of core eudicot flower development.   Here, we used synteny network approaches to compare the synteny patterns between the basal and core eudicots, focusing on transcription factor families with major roles in flower development. Synteny network analysis constructs clusters in which the nodes represent the target genes and associated adjacent genomic blocks, and the edges connected between nodes represent the syntenic relationships. We built synteny networks of TCP, NAC, MYB, and MADS-box gene families for four basal eudicots (Aquilegia caerulea, Nelumbo nucifera, B. sinica, and T. sinense) and five core eudicots (Vitis vinifera, Phaseolus vulgaris, Arabidopsis thaliana, Daucus carota, and Solanum lycopersicum). We found that genes of MYB and MADS-box gene families are more likely to lose binding motifs after gene duplications compared with other tested gene families. Principal components analysis performed based on the parameters of nodes and edges from all of our synteny clusters distinguished the core eudicots from basal eudicots examined. This suggests that there was shuffling of syntenic blocks of these genes that are related to floral development coincident with the phylogenetic position of gamma. Changes in gene order can directly affect gene regulation through changes in the location of enhancers, silencers, and histone density, exemplified by HOX gene cluster evolution in animals. Further examination of all synteny network clusters may reveal specific clusters with distinct syntenic patterns between basal and core eudicots, which may illuminate whether synteny is associated with changes in gene expression or function that are involved in the origin of the pentamerous flower.

1 - LaGuardia Community College, Natural Science Department, 31-10 Thomson Avenue Long Island City, New York, NY, 11101, USA
2 - St John's University, Biological Sciences, 8000 Utopia Parkway, Queens, NY, 11439, USA
3 - Museum Road And Newell Drive, Gainesville, FL, 32611, United States
4 - University of Saskatchewan, Computer Science, 176 Thorvaldson Building, 110 Science place, Saskatoon, SK, Canada
5 - University of Ottawa, Department of Mathematics and Statistics, Ottawa, ON, K1N6N5, Canada
6 - Biological Sciences, 109 Cooke Hall, Buffalo, NY, 14260, United States
7 - University of Ottawa, Ottawa, ON, K1N6N5, Canada
8 - University Of Florida, Florida Museum Of Natural History, PO Box 117800, Gainesville, FL, 32611, United States
9 - University of Florida, Gainesville, FL, 32611, USA
10 - St. John's University, Department Of Biological Sciences, St. Albert Hall Rm 257, 8000 Utopia Pkwy, Jamiaca, NY, 11439, United States

Keywords:
basal eudicots
core eudicot
floral morphology
network
synteny
whorled pentamerous flower.

Presentation Type: Poster
Session: P1, Development and Structure Posters
Location: Virtual/Virtual
Date: Monday, July 19th, 2021
Time: 5:00 PM(EDT)
Number: P1DS015
Abstract ID:984
Candidate for Awards:Developmental and Structural Section best poster