|Friday, July 09|
Dr. Coudert's lab investigates how the shape of biological organisms is established. His research focuses on mosses and aims to understand the molecular mechanisms underpinning the development and evolution of their branching patterns and phyllotaxis, which constitute major determinants of shape diversity in plants. https://yoancoudert.wixsite.com/labo http://www.ens-lyon.fr/RDP/spip.php?rubrique20#yoan
Off with their head: a tale of decapitation and auxin
* Yoan Coudert, CNRS, France
Branching patterns are a primary determinant of plant architecture and strongly impact on productivity by regulating light harvesting potential and resource allocation. Plants colonized land over 450 million years ago, and underwent architectural diversification in the haploid (gametophyte) and diploid (sporophyte) genetic stages of the life cycle independently. Although similar branching mechanisms evolved in both genetic stages, our functional understanding of branching is limited to diploid flowering plant models such as Arabidopsis. To test whether the same molecular cues regulate similar lateral branching mechanisms that have evolved independently, we previously undertook a computational and genetic analysis of branching patterns in the haploid leafy shoot of a moss, Physcomitrium patens, and showed that a simple model co-ordinating the activity of shoot tips across the plant can account for the branch distribution, and that three known hormonal regulators of branching in flowering plants generate the pattern. To explore further the underpinning genetic mechanism, we analysed the transcriptome of decapitated leafy shoots, in which branch initiation is activated. We identified new roles for auxin signalling and metabolism, which I will discuss.