Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Han, Jiahong [1], Gray, Ela [2], Jabaily, Rachel [3], Howarth, Dianella [4].

Duplication and expression of CYCLOIDEA-like genes in Goodeniaceae.

Goodeniaceae is a rich flowering plant family including about 420 species placed in 12 genera, and chiefly native to Australia and the Pacific Islands, with abundant, showy flowers in a riot of colors and shapes. Collectively known as “fan flowers”, the group is named for the unique flower shape most commonly associated with it. Fan flowers commonly have all five petals positioned on the ventral (abaxial) side, opposite of a deep dorsal (adaxial) slit down the length of the corolla tube. Floral symmetry is actually highly variable across the family (Fig. 1), though some clades contain much greater diversity of floral forms, and extant species, than their sister clades. We aim in this study to examine the developmental regulation of floral symmetry, examining the floral symmetry gene, CYCLOIDEA (CYC), in Goodeniaceae, especially given that shifts in floral symmetry correlate with lineage diversification in this group. In order to determine the overall pattern of CYC gene evolution in Goodeniaceae, our first step utilizes broad sampling across Goodeniaceae targeting the major clades Scaevola s.l. and Goodenia s.l. We currently have 98 Goodeniaceae CYC- like gene copies sequenced from 25 species. Similar to other bilaterally symmetrical groups there appears to have been duplications in both CYC2 and CYC3. The CYC3 duplication appears to be shared with Asteraceae, based on the placement of sequences from Helianthus. This is the only known case of a shared duplication with a core eudicot CYC clade that spans separate derivations of bilateral symmetry. Additionally, given our current sampling, we have so far uncovered an apparent duplication event around the divergence of Scaevola s.l. in CYC3A, coincident with the morphological shift to a fan flower. Ultimately, we aim to map morphological transitions and CYC paralog expression changes onto the CYC-like gene phylogeny to see if nodes with altered rates of molecular evolution or uneven topology correspond with points of transition in floral symmetry and/or duplication or expression changes of CYC-like genes.

Broader Impacts:

1 - St. John's University, Biology, 8000 Utopia Pkwy, Jamaica, New York, 11439, United States
2 - St. John's University, 8000 Utopia Pkwy, Jamaica, New York, 11439, United States
3 - Rhodes College, Botany, 2000 N. Parkway, Memphis, TN, 38112, USA
4 - St. John's University, Department of Biological Sciences, 8000 Utopia Parkway, Queens, NY, 11439, USA

Keywords:
Goodeniaceae
CYCLOIDEA
Phylogenetics
Scaevola
Australia.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PEV004
Abstract ID:706
Candidate for Awards:None