Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Nikolov, Lachezar Atanasov [1], Kwantes, Michiel [2], Perez, Miguel Anton [2], Gan, Xiangchao [2], Tsiantis, Miltos [2].

Genetic underpinnings of leaf diversity in the mustard family (Brassicaceae).

The recent growth of genetic resources in model organisms and the advancement of phylogenetic comparative methods bring us closer to understanding how different morphologies originate and diversify but fundamental challenges remain to translate this knowledge to the broader diversity of plants. Leaf shape in mustards offers an attractive system to address the molecular mechanisms that cause morphological differences because it is a diverse trait in the family and much has been learned from model species like Arabidopsis thaliana and Cardamine hirsuta about the genetics of leaf development. To gain further insight into the mechanisms that gave rise to different leaf shapes, we generated expression profiles of young leaves from the simple leaved Arabidopsis and the compound leaved Cardamine. We characterized ca. 40 transcription factors expressed at higher levels in Cardamine than in Arabidopsis using transcriptional reporters, and defined novel expression domains that may underlie novel morphogenetic domains. We expressed these genes in Arabidopsis to test whether they are sufficient to generate leaf complexity in simple leaves, and reduced their expression in Cardamine to assess whether they are necessary for compound leaf development. Our results reveal a distribution of effects of the differentially expressed transcription factors, with several regulators contributing disproportionally to leaf shape. These findings suggest that evolutionary tinkering in leaf morphology occurs via a limited number of evolutionary paths, which are underscored by a defined set of major effect molecular players acting in morphological transitions at different phylogenetic scales.

1 - Max Planck Institute Of Plant Breeding Research, Carl-von-Linné-Weg 10, Koeln, N/A, 50829, Germany
2 - Max Planck Institute for Plant Breeding Research

Keywords:
Leaf morphology
leaf development
morphological evolution
compound leaf
gene expression
comparative transcriptome
gene regulatory network
Functional genomics
regulatory evolution
Cardamine hirsuta 
Brassicaceae.

Presentation Type: Oral Paper
Session: 2, Evolution and Development
Location: 200/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 11:15 AM
Number: 2013
Abstract ID:780
Candidate for Awards:None