@article{StreubelFritzTeltowetal.2018, author = {Streubel, Susanna and Fritz, Michael Andre and Teltow, Melanie and Kappel, Christian and Sicard, Adrien}, title = {Successive duplication-divergence mechanisms at the RCO locus contributed to leaf shape diversity in the Brassicaceae}, series = {Development : Company of Biologists}, volume = {145}, journal = {Development : Company of Biologists}, number = {8}, publisher = {Company of Biologists}, address = {Cambridge}, issn = {0950-1991}, doi = {10.1242/dev.164301}, pages = {10}, year = {2018}, abstract = {Gene duplication is a major driver for the increase of biological complexity. The divergence of newly duplicated paralogs may allow novel functions to evolve, while maintaining the ancestral one. Alternatively, partitioning the ancestral function among paralogs may allow parts of that role to follow independent evolutionary trajectories. We studied the REDUCED COMPLEXITY (RCO) locus, which contains three paralogs that have evolved through two independent events of gene duplication, and which underlies repeated events of leaf shape evolution within the Brassicaceae. In particular, we took advantage of the presence of three potentially functional paralogs in Capsella to investigate the extent of functional divergence among them. We demonstrate that the RCO copies control growth in different areas of the leaf. Consequently, the copies that are retained active in the different Brassicaceae lineages contribute to define the leaf dissection pattern. Our results further illustrate how successive gene duplication events and subsequent functional divergence can increase trait evolvability by providing independent evolutionary trajectories to specialized functions that have an additive effect on a given trait.}, language = {en} } @misc{FritzRosaSicard2018, author = {Fritz, Michael Andre and Rosa, Stefanie and Sicard, Adrien}, title = {Mechanisms Underlying the Environmentally Induced Plasticity of Leaf Morphology}, series = {Frontiers in genetics}, volume = {9}, journal = {Frontiers in genetics}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-8021}, doi = {10.3389/fgene.2018.00478}, pages = {25}, year = {2018}, abstract = {The primary function of leaves is to provide an interface between plants and their environment for gas exchange, light exposure and thermoregulation. Leaves have, therefore a central contribution to plant fitness by allowing an efficient absorption of sunlight energy through photosynthesis to ensure an optimal growth. Their final geometry will result from a balance between the need to maximize energy uptake while minimizing the damage caused by environmental stresses. This intimate relationship between leaf and its surroundings has led to an enormous diversification in leaf forms. Leaf shape varies between species, populations, individuals or even within identical genotypes when those are subjected to different environmental conditions. For instance, the extent of leaf margin dissection has, for long, been found to inversely correlate with the mean annual temperature, such that Paleobotanists have used models based on leaf shape to predict the paleoclimate from fossil flora. Leaf growth is not only dependent on temperature but is also regulated by many other environmental factors such as light quality and intensity or ambient humidity. This raises the question of how the different signals can be integrated at the molecular level and converted into clear developmental decisions. Several recent studies have started to shed the light on the molecular mechanisms that connect the environmental sensing with organ-growth and patterning. In this review, we discuss the current knowledge on the influence of different environmental signals on leaf size and shape, their integration as well as their importance for plant adaptation.}, language = {en} }