Abstract Detail

Kaplan Memorial Lecture

Alvarez-Buylla Roces, Elena [1].

From genes to complex networks and morphologies in plant evolution.

Understanding how information contained in genes is expressed as phenotypes and deriving formal frameworks to search for generic aspects of developmental constraints and evolution remains one of the main challenges of contemporary biological research. Evolutionary approaches to developmental mechanisms and systems biology, including high-throughput functional genomic studies and models of complex developmental gene regulatory networks, constitute two main approaches to meet such challenge. Using examples of flower patterns from the Pandanales, particularly the Triuridaceae, and the Zingiberales, as well as detailed molecular genetic data available for Arabidopsis thaliana, both general principles and specific examples of how genotypes map unto phenotypes, and morphological evolution, will be discussed. Theoretical, experimental, molecular genetic, as well as comparative morphology and evolutionary approaches will be integrated to summarize some salient contributions that have been made in plant evo-devo studies in our research group and beyond. The robustness and overall conservation of the main floral bauplan of angiosperms, that consists of concentric whorls of sepals, petals, stamens and carpels, as well as the exceptions to such plan will be approached. Gene regulatory network models will be used to address the restriction in the types and arrangements of floral organs among angiosperms, as well as how variants in the overall conserved floral plan may arise, including the unique homeotic floral arrangement of the Mexican endemic triurid Lacandonia schismatica (Triuridaceae): a mycoheterotrophic monocotyledonous plant with hermaphroditic homeotic reproductive axes that stands alone among 250,000 species of angiosperms, with central stamens surrounded by a peripheral gynoecium. We will also summarize molecular genetic data and evolutionary analyses towards the ultimate goal of exploring the mechanisms involved in the evolution of this unique homeotic flower. Another source of morphological diversity among flowers in angiosperms concerns the diverse morphogenetic patterns of particular floral organs. For example, several Zingiberales have petaloid stamens, or stamens with laminar, instead of radial, filaments. I will discuss novel hypotheses and explorations combining data derived from transcriptomic and classical molecular genetic experiments to document the involvement of the regulatory modules underlying floral organ specification and polarity to understanding stamen morphology in the Zingiberales. The need to further develop theoretical frameworks that combine models of gene regulatory networks, epigenetic landscapes that emerge from such networks, with mechanisms that provide positional information, and thus enable considerations of the spatio-temporal morphogenetic patterns, will be discussed in order to integrate the examples provided.

Broader Impacts:

1 - Universidad Nacional Autónoma de México, Instituto de Ecología, Cd. Universitaria, Mexico City, DF, 04510, Mexico

Keywords:
Gene regulatory networks
Morphological evolution
evo-devo
epigenetic landscapes
developmental restrictions
Triurids
Zingiberales.

Presentation Type: Special Presentation
Session: S3
Location: Belle-Chasse/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 4:00 PM
Number: S3001
Abstract ID:891
Candidate for Awards:None