- 12 January 2021
Responsible : Emmanuelle Bayer Research Director

Emmanuelle Bayer obtained her PhD in 2005 (A. Maule; John Innes Centre England), her subject of study was the identification of plasmodesm regulating proteins. After a post-doc in Switzerland, on polarized auxin flux and regulation of phyllotaxis in plants (2006-2009; C Kuhlemeier, Institute of Plant Science Switzerland). E. Bayer obtained a position at CNRS as research director in the Membrane Biogenesis laboratory, since 2015 she leads her own group and obtains an ERC funding in 2017 for her research project “BRIDGING”. Her work was awarded the CNRS bronze medal in 2018. Since January 2019 she joined the EMBO Young Investigator Program.





Technical manager: Magali Grison

Recruited in 2010 at the LBM in the team Intercellular communication mediated by plasmodesmata, Magali obtained her EPHE degree in 2013, and her PhD thesis in 2018 on the involvement of membrane nanodomains in intercellular communication mediated by plasmodesmata. She is now in charge of the development of high resolution photonic microscopy adapted to our topic and is also the technical manager of the team.
Members:
J. Perez Sancho (Post-doc), M. Smokvarska (Post-Doc), M. Glavier (IR), V. Dietrich (AI), T. Souza-Moraes (post-Doc), ZQ. Li (PhD), H. Moreau (Post-Doc), José Cana Quijada (IE)








Thematique:
In plants, intercellular communication is largely achieved through plasmodesmata, membrane pores that cross the cell wall and create symplastic continuity between cells. Plasmodesms play a key role in the coordination of developmental processes and defense mechanisms against pathogens. They are also hijacked by viruses that are able to structurally modify them to propagate their viral genome from cell to cell.
Plasmodesmata have a unique membrane organization: they are crossed by a “tube” of endoplasmic reticulum (ER) which is in intimate contact with plasma membrane (PM), delimiting the pores. The two membranes are only a few nm apart (~10 nm) and connected by so far unidentified “tethers”. The space between the ER and the PM determines the degree of opening of plasmodesmata and their ability to traffic between cells.
Our team seeks to understand how the membrane organization of plasmodesmata is critical for the regulation of intercellular exchanges in plants. We want to answer the following questions:

Plasmodesmata establish ER and PM continuity between cells. Tilsner et al. 2015.
- Why do the ER and PM directly contact each other at plasmodesmata and what are the elements that regulate these membrane junctions?
- What is the ultrastructural organization of plasmodesmata and the rearrangements induced during macromolecule transport?
- What role does membrane lipid play in the formation and functionality of specialized plasmodesmata microdomains.
To answer these questions we use biochemical, proteomic/lipidomic, membrane biophysical, cell/molecular biology and high resolution microscopy (electron tomography) approaches.


substack_1-58_-1.avi
PD ultrastructure using electron tomography
Key Article:
- Petit J, Li ZP, Nicolas WJ, Grison MS, Bayer EM# (2020). Dare to change , the dynamics behind plasmodesmata-mediated cell-to-cell communication. Current Opinion in Plant Biol.53:80-8.
- Grison MS*, Kirk P, Brault M, Na Wu X, Schulze WX, Benitez-Alfonso Y, Immel F, Bayer EM* (2019) Plasma membrane associated Receptor Like Kinases relocalise to plasmodesmata in response to osmotic stress. Plant Physiol. 181:142-16.
- Brault ML+, Petit JD+, Immel F, Nicolas WJ, Glavier M, Brocard L, Gaston A, Fouché M, Hawkins TJ, Crowet J, Grison SM, Germain V, Rocher M, Kraner M, Alva V, Claverol S, Paterlini A, Helariutta Y, Deleu M, Lins L, Tilsner J*, Bayer EM* (2019)
- Multiple C2 domains and transmembrane region proteins (MCTP) tether membranes at plasmodesmata. EMBO Rep. e47182, p1–26.
- Yan D+, Yadav SR+, Paterlini A, Nicolas WJ, Petit JD, Brocard L, Belevich I, Grison MS, Vaten A, Karami L, El-Showk S, Lee JY, Murawska GM, Mortimer J, Knoblauch M, Jokitalo E, Markham JE, Bayer EM*, Helariutta Y*. (2019) Sphingolipid biosynthesis modulates plasmodesmal ultrastructure and phloem unloading. Nat Plants 5: 604–615.
- Nicolas W, Grison MS, Trépout S, Gaston A, Fouché M, Cordelières F, Oparka K, Tilsner J, Brocard L*, & Bayer EM*. (2017) Architecture and permeability of post-cytokinesis plasmodesmata lacking cytoplasmic sleeve. Nature Plants. 3:17082
- Tilsner J, Nicolas W, Rosado A and Bayer EM* (2016) Staying tight: plasmodesmal membrane contact sites and the control of cell-to-cell connectivity in plants. Annual Review of Plant Biology 67:23.1-23.28
- Grison MS+, Brocard L+, Fouillen L, NicolasW, Wewer V , Dörmann P, Nacir H, Benitez-Alfonso Y, Claverol S, Germain V, BouttéY, Mongrand Sand Bayer EM* (2015). Specific membrane lipid composition is important for PD function in Arabidopsis. The Plant Cell 27(4):1228-50
Collaborations:
Jens Tilsner, School of Biology, University of Saint Andrews, U.K.
Yvon Jaillais, ENS/CNRS, Lyon, France.
Yrjö Helariutta, Sainsbury Laboratory, Cambridge, U.K.
Abel Rosado, University of British Columbia, Canada.
Laurence Lins, Biophysique moleculaire aux interfaces, University of Liège, Belgium.
Vikram Alva, Max Planck Institute for Developmental Biology, Germany
Lysiane Brocard, Bordeaux Imaging Centre, Bordeaux, France.
Sylvie German-Retana, National Agricultural Research Institute, University of Bordeaux, France
Former members:
Marie Brault (IE ANR) William Nicolas (PhD) A. Gaston (Post-doc ANR) M. Fouché (IE ANR)