Postdoc position in plant development: Morphogenesis and phenotypic plasticity
of Marchantia splash-cups in relation to dispersal
The fixed life of plants and fungi requires specific strategies to disperse progeny. Here, we investigate how plants adjust their dispersal to their environment, using splash-cups as a model. These are specialised cup-shaped organs producing reproductive bodies (spores, propagules, or male gametes) that are entrained by raindrops bouncing off the cups. Splash-cups enable spreading or fertilisation close to parental organisms, increasing the probability of effective establishment and maintenance in an already colonised habitat. Splash-cups have evolved independently in liverworts (mostly Marchantia genus), in mosses, in flowering plants, and in fungi, and in lichens (Brodie, 1951). We aim at testing the hypothesis that phenotypic plasticity of splash-cup morphology in Marchantia species (spp.) enables optimal dispersal of vegetative propagules (gemmae).
We chose to work on liverworts from the Marchantia genus for the following reasons (also see Laplaud et al. 2024). First, Marchantia polymorpha is the only well-established genetic model (Bowman et al. 2022) among all splashcup making plants and fungi. Second, Marchantia spp. are distributed worldwide from tropical to arctic climates and from seashore to mountaintops. Third, M. globosa colonies are broadly distributed along the elevation gradient in La Réunion island, and are likely phenotypically plastic (Bischler & Boisselier-Dubayle, 1993). Marchantia spp. reproduce asexually by developing gemmae, inside an organ known as the gemma-cup (Figure). The upper part of the cup functions as a splash-cup, with rain ejecting gemmae as far as 1 m. We found that splash-cup size of M. globosa correlates with altitude in La Réunion island (our preliminary field data), but we have not identified environmental factors potentially sensed. Gemma-cups in M. polymorpha are phenotypically plastic (our preliminary data). Previous research has identified transcription factors and phytohormones that control gemma-cup initiation and development (Kato et al. 2020). How these regulatory pathways are modulated by environmental factors is still unknown.
The postdoc project aims at characterising the phenotypic plasticity of splash-cups, at describing gemma-cup morphogenesis, and at understanding the molecular basis of phenotypic plasticity in polymorpha. Approaches may include optical coherence tomography, confocal microscopy, mutant generation, and transcriptomics. Work in M. polymorpha may be extended to M. globosa according to progress, aiming at identifying pathways that enable adaptation in the field.
Candidates are expected to have a background in cell and/or developmental biology, and to be interested in working in an interdisciplinary team. The postdoc will have access to all necessary materials and equipment. The start date is relatively flexible and the initial contract will be of two years. For questions and informal applications (curriculum vitæ, research interests, references), please contact Arezki Boudaoud (arezki.boudaoud@polytechnique.edu) and Stéphanie Drevensek (stephanie.drevensek@polytechnique.edu) as early as possible. It is expected that official applications will be open from June 16th to September 14th 2024 at https://emploi.cnrs.fr/default.aspx (select FTC scientist and use ‘plant development’ as a keyword to find the ad).
References:
- HJ Brodie 1951 The splash-cup dispersal mechanism in plants. Can J Bot 29 224
- H Bischler & C Boisselier-Dubayle 1993 Variation in a polyploid, dioicous liverwort, Marchantia globosa Am J Bot 80 953
- JL Bowman et al. 2017 Insights into Land Plant Evolution Garnered from the Marchantia polymorpha Genome Cell 171 287–304
- J Edwards, M Laskowski, TI Baskin, N Mitchell & B DeMeo 2019 The Role of Water in Fast Plant Movements Integ Comp Biol 59 1525
- H Kato et al. 2020 Gemma cup and gemma development in Marchantia polymorpha New phytol 228 459
- V Laplaud, E Muller, V Demidova, S Drevensek & A Boudaoud 2024 Assessing the hydromechanical control of plant growth. J. Roy. Soc. Interface 2 20240008