Agnès BOUTET

Key words

Embryogenesis, Kidney, Stem cells, Lifelong development, mTOR signaling pathway

Research activity

I am a developmental biologist interested in the kidney of elamobranchii, a subclass of Chondrichthyes, or cartilaginous fish.

The vertebrate kidney is made of nephrons, the function units that are responsible of blood filtration. During embryogenesis, all the epithelial cells of the nephron arise from a population of mesenchymal cells (the nephron progenitor cells (NPCs)) through a mesenchymal to epithelial transition (MET). While nephrogenesis, the process of nephron formation, stops around birth in mammals, some additional nephrons can be produced at the juvenile and adult stage in cartilaginous fish.

Mammalian NPCs cease propagation and are terminally differentiated within few days after birth. The fact that cartilaginous fish keep the ability to form new nephrons at the post-embryonic stage relies on the persistence of the pool of NPCs in renal tissues. Therefore, partial nephrectomy can lead to the formation of new nephrons in cartilaginous fish but not in mammals leaving them with a limited kidney regeneration capacity.

What is the key mechanism controlling NPCs persistence beyond embryogenesis in cartilaginous fish? Are these cells receiving a key signal allowing their persistence? Would it be possible to increase the lifespan of mammalian NPCs using this key signal?

Our research project aims to address these questions using the small-spotted catshark (Scyliorhinus canicula) as a model.

In a work published in 2025, we characterized the nephrogenic area of the juvenile catshark kidney and demonstrated that the molecular markers of the NPCs are conserved across vertebrates. We also reported that some targets of the mTOR signaling pathway, a central pathway in translation initiation, are more expressed in the differentiated epithelial cells of the nephron compared to the NPCs. More generally, we observed that the NPCs of the juvenile catshark display a low protein synthesis rate compared to differentiated epithelial cells, which is consistent with results obtained in several adult stem cell populations and embryonic stem cells.

We are continuing our work using high throughput approaches to analyze the post-embryonic nephrogenic area of the catshark both in a physiological context and upon kidney injury.

Projects funded as principal investigator

SeaKidStem

2017-2018: Questioning the control of protein synthesis in kidney regeneration: a key step to explore stem cell homeostasis. Funding: Programme Emergence @ Sorbonne Universités.

DigitalMarine

2018 – 2021: The DigitalMarine project: development of an online distance learning platform. Funding: Erasmus+ programme.

French Cancer League (Western region)

2022: The role of protein synthesis and mTOR signaling in the homeostasis of stem cells, progenitor cells and tissue regeneration. Funding: French Cancer League. 

Editorial activity

Editor of the Handbook of Marine Model Organisms in Experimental Biology Established and Emerging. CRC Press. Released in November 2021

Teaching at Sorbonne Université

I am in charge of a course in cellular and developmental biology for bachelor students (Bachelor in Biology, Modeling and data analysis) and of a course focused on marine models in experimental biology (the Schmid Training Course) for M1 students (Master in Cellular and Molecular Biology (BMC)).

I am also involved in courses for the two professional bachelor degrees based in Roscoff (in marine bio-industries and biotechnology and in food security): tutored projects, recombinant DNA technology, genetically modified organisms, endocrine disruptors.

Selected papers

Lund-Ricard Y, Cormier P, Morales J, Boutet A. mTOR Signaling at the Crossroad between Metazoan Regeneration and Human Diseases. Int J Mol Sci. 2020

Lund-Ricard Y, Calloch J, Glippa V, Vandenplas S, Huysseune A, Witten PE, Morales J, Boutet A. Postembryonic Maintenance of Nephron Progenitor Cells with Low Translational Activity in the Chondrichthyan Scyliorhinus canicula. J Am Soc Nephrol. 2025