Could you introduce yourself?

I am a CNRS Research Director working at the Laboratoire de Biogenèse Membranaire in Bordeaux. My background is inplant cell biology, with a long-standing interest in how cells communicate with each other. Over the years, I have focused on plasmodesmata, these nanoscale channels that connect plant cells and allow molecules to move from one cell to another.

I am currently leading a research group studying membrane dynamics and cell-cell communication in plants. I am also involved in the direction of the Bordeaux Imaging Center, being Deputy Director since january 2025.

You have recently been awarded the CNRS Silver Medal. Could you tell us more about your research and its main focus?

Our work addresses a simple question that is still largely unresolved:

How do plant cells control what moves between them?

We focus on plasmodesmata and more specifically on the role of membranes, lipid-protein interaction in regulating this exchange. We combine cell biology, genetics, in silico modelling and advanced imaging to dissect how these channels form, how they open or close, and how they contribute to plant development and responses to the environment.

How does microscopy contribute to your work?

Microscopy is central to everything we do. Plasmodesmata are extremely small (30 nm in diameter) and highly dynamic, so we need imaging approaches that allow us to see both their structure and their behavior in living tissues.

Without microscopy, we simply could not access these processes.

Which microscopy techniques are especially important for your research?

We rely on a combination of electron and advanced light microscopy to bridge structure and dynamics across scales. Super-resolution approaches such as STED and expansion microscopy allow us to resolve the nanoscale organization of plasmodesmata, while electron tomography provides detailed views of their internal architecture. At the tissue level, we use serial block-face scanning electron microscopy to map their distribution across organs.

To capture dynamics in living tissues, we use two-photon microscopy, in particular to photoactivate fluorescent tracers and follow their movement from cell to cell. We complement this with lattice light-sheet imaging, as well as approaches such as FRAP and FLIP, to quantify molecular mobility and intercellular trafficking in real time.

How does your work contribute to innovation in microscopy applied to plant science?

Our work pushes microscopy in two directions. On one side, we adapt existing methods to plant tissues, which are often challenging to image. On the other, we develop new strategies to track intercellular trafficking with high spatial and temporal resolution. This includes approaches to follow molecules as they move across individual plasmodesmata.

This effort is very much collective. We work closely with the Bordeaux Imaging Center and collaborate with leading groups in single-molecule imaging, in particular the team of Laurent Cognet (France-BioImaging R&D team) .

These interactions are key to pushing the limits of what we can resolve in living plant tissues.

As deputy director of the Bordeaux Imaging Center and a member of a France-BioImaging R&D team, what message would you like to share with researchers working in plant biology?

Imaging is not just a technical step, it shapes the questions you can ask and also opens access to questions that were not accessible before. I would encourage researchers to engage early with imaging platforms and to build real interactions with imaging specialists. These platforms are essential for the whole community. Having highly skilled engineers with strong expertise who work hand in hand with researchers is a real strength of the French system, and something that is invaluable for moving projects forward. I hope this model will continue to be strongly supported in the coming years.

Plant systems bring specific constraints, but they also open unique possibilities. There is still a lot to explore, and progress will come from close exchanges between researchers and engineers specialized in imaging and data analysis.