Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Han, Jiahong [1], Berger, Brent [1], ricigliano, vincent [2], Shepherd, Kelly [3], Tong, Jingjing [4], Thompson, Veronica [5], Lim, Aedric [1], Howarth, Dianella [1].

Phylogenetics and expression of CYCLOIDEA-like genes in Goodeniaceae.

Shifts in floral symmetry, especially from radial symmetry to bilateral symmetry, are often correlated with changes in diversification rates and pollinator specificity. Evidence from multiple, independent lineages demonstrates that these shifts are associated with gene duplication and, often, dorsal restriction in expression of transcription factors in the TCP gene family, specifically the CYCLOIDEA-like genes. In this study, we examine the predominantly Australian and Pacific Island fan-flowers of the Goodeniaceae, which contains both radially and bilaterally symmetrical flowered species. We find evidence for three CYC-like gene paralogs (CYC1, CYC2, and CYC3) in Goodeniaceae that correspond to the same three clades found across core eudicots. Unlike other bilaterally symmetrical groups where duplicate CYC2 genes predominate, Goodeniaceae appears to have a single GoodCYC2 clade and two GoodCYC3 clades, GoodCYC3A and GoodCYC3B. This is of special interest given the strongly ventrally placed petals in many bilateral Goodeniaceae and the possibility that the duplication of GoodCYC3 plays a greater role in the ventral zone of the flower. Also of note, there are several tip duplications in GoodCYC3A and GoodCYC3B, coincident with the morphological shift to a fan flower. Using the fan-flowered Scaevola aemula, we perform realtime qPCR and show that most CYC-like copies are expressed across the entire corolla. SaeCYC2 was more strongly expressed in dorsal petals than in ventral petals, the predominant pattern found in other core eudicots. Conversely, both SaeCYC3 paralogs have the highest expression in ventral petals in S. aemula. Taken together, these results indicate SaeCYC2 is expressed in a similar pattern to that in other groups, while SaeCYC3 exhibits the opposite expression pattern, being more highly expressed ventrally.

1 - St. John's University, 8000 Utopia Pkwy, Jamaica, NY, 11439, United States
2 - USDA-ARS, 2000 E Allen Rd, Tucson, AZ, 85719, United States
3 - Western Australian Herbarium, Locked Bag 104, Bentley Delivery Centre, Perth, Western Australia, 6983, Australia
4 - St. John's University, 8000 Utopia Pkwy, Jamaica, NY, 11439, USA
5 - UC Davis

Keywords:
Floral symmetry
CYCLOIDEA
Goodeniaceae
qPCR
gene expression.

Presentation Type: Poster
Session: P, Evolutionary Developmental Biology (Evo-Devo)
Location: Exhibit Hall/Omni Hotel
Date: Monday, June 26th, 2017
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PEV004
Abstract ID:424
Candidate for Awards:None