Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Berger, Brent [1], ricigliano, vincent [2], Savriama, Yoland [3], Lim, Aedric [4], Thompson, Veronica [5], Howarth, Dianella [1].

Geometric morphometrics reveals shifts in flower shape symmetry and size following gene knockdown of CYCLOIDEA and ANTHOCYANIDIN SYNTHASE.

While floral symmetry has traditionally been assessed qualitatively, recent advances in geometric morphometrics have opened up new avenues to specifically quantify flower shape and size using robust multivariate statistical methods. In this study, we examine, for the first time, the ability of geometric morphometrics to detect morphological differences in floral dorsoventral asymmetry following virus-induced gene silencing (VIGS). Using Fedia graciliflora Fisch. & Meyer (Valerianaceae) as a model, corolla shape of wildtype flowers was compared using canonical variate analysis to knockdown phenotypes of CYCLOIDEA2A (FgCYC2A), ANTHOCYANIDIN SYNTHASE (FgANS), and empty vector controls. Wildtype flowers and all VIGS treatments were morphologically distinct from each other, suggesting that VIGS may cause subtle shifts in floral shape. Knockdowns of FgCYC2A were the most dramatic, affecting the position of dorsal petals in relation to lateral petals, thereby resulting in more actinomorphic-like flowers. Additionally, FgANS knockdowns developed larger flowers with wider corolla tube openings. These results provide a method to quantify the role that specific genes play in the developmental pathway affecting the dorsoventral axis of symmetry in zygomorphic flowers. Additionally, they suggest that ANS may have an unintended effect on floral size and shape.

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 - University of Helsinki, Institute of Biotechnology, PO Box 56 (Viikinkaari 5), Helsinki, FIN-00014, Finland
4 - RESA Power Solutions, 1180 Horizon Dr. Suite E, Fairfield, CA, 94533, USA
5 - UC Davis, Plant Biology, Davis, CA, USA

Keywords:
Geometric morphometrics
Virus-induced gene silencing
CYCLOIDEA
Fedia graciliflora
Floral symmetry
ANTHOCYANIDIN SYNTHASE.

Presentation Type: Oral Paper
Session: 34, Evo-Devo
Location: Sundance 2/Omni Hotel
Date: Wednesday, June 28th, 2017
Time: 10:45 AM
Number: 34011
Abstract ID:436
Candidate for Awards:None