Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Edwards, Molly [1], Ballerini, Evangeline S. [2], Choi, Gary [3], Mahadevan, L. [4], Hodges, Scott [5], Kramer, Elena [6].

Exploring the developmental and genetic basis of complex petal morphologies in bee- and hummingbird-pollinated Aquilegia (columbine).

The petals of Aquilegia (columbine) form elongated, three-dimensional nectar spurs that vary in shape and length depending on their pollinators (bee, hummingbird, or hawkmoth). The bee syndrome is ancestral, and there have been multiple independent transitions from bee to hummingbird, and hummingbird to hawkmoth syndromes. Petal development of hummingbird- and hawkmoth-pollinated species has been well-characterized: early in development, differential cell division creates an out-pocketing at the site of the nascent spur; then, highly anisotropic cell elongation generates 90% of the final size of the long, straight spurs. The nectar spurs of bee-pollinated species, however, are short and curved. What cellular processes during development are responsible for creating curvature in the spur, and how do they differ from those in straight spurs? Given that the bee syndrome is the ancestral state, we can also ask whether the same developmental strategy is deployed across bee-pollinated species to generate spur curvature. We have begun to answer these questions using a comparative developmental approach and are using the results to inform a two-pronged investigation into the genetic architecture underlying this trait. We have conducted a QTL mapping experiment on F2 hybrids of curved-and straight-spurred parents as well as RNA-seq on the petals of those same parents, yielding a wealth of insight into the genetic basis of nectar spur curvature.

1 - Harvard University, Biolabs Room 1119, 16 Divinity Ave, Cambridge, MA, 02138, United States
2 - University of California, Santa Barbara, Department of Ecology, Evolution, & Marine Biology, 4105 Life Sciences Building, Santa Barbara, CA, 93106, USA
3 - Paulson School of Engineering & Applied Sciences, Harvard University, Department of Applied Mathematics, Harvard University Pierce Hall rm 405, 29 Oxford St, Cambridge, MA, 02138, USA
4 - Paulson School of Engineering & Applied Sciences, Harvard University,, Department of Applied Mathematics, Harvard University Pierce Hall 322, 29 Oxford St, Cambridge, MA, 02138, United States
5 - Department Of Ecology & Marine Biology, Department Of Ecology & Marine Biology, University Of California, Santa Barbara, CA, 93106, United States
6 - Harvard Univ., OEB, 16 Divinity Avenue, Cambridge, MA, 02138, United States

Keywords:
aquilegia
nectar spur
Petal.

Presentation Type: Oral Paper
Session: EVDV1, Evolutionary Developmental Biology (Evo-Devo)
Location: Tucson E/Starr Pass
Date: Monday, July 29th, 2019
Time: 4:45 PM
Number: EVDV1013
Abstract ID:436
Candidate for Awards:Katherine Esau Award