Permanent CNRS researcher, group "Evo-devo of the flower"
Laboratory for Plant Reproduction and Development, ENS de Lyon, France, tel : +33 426731476


Current research: Petunia petal development and evolution

Petals have been a key innovation during flower evolution since they greatly increase pollination efficiency and specificity. We study petal development in Petunia, where petals are fused in a tube that opens with brightly coloured limbs. We have isolated cell-layer-specific mutants in the petal homeotic gene PhDEF, which indicates that epidermal expression of PhDEF is sufficient for limb development, while mesophyll expression of PhDEF is sufficient for tube development. Our goal is to understand the mechanistic basis for PhDEF differential function in the two cell layers of the petal.

Funding: ANR JCJC FLOWER-LAYER (2020-2024), Elan ERC grant (IDEX Lyon, 2018-2021)

Other team members involved: Emma Désert (PhD student), Quentin Cavallini-Speisser (PhD student), Patrice Morel (permanent researcher), Pierre Chambrier (assistant engineer), Michiel Vandenbussche (research director).

Previous research: Petal number robustness

Petal number is generally a robust trait but has become variable in Cardamine hirsuta, a member of the Brassicaceae like Arabidopsis thaliana. During my post-doc in the group of Angela Hay, I investigated the genetic basis of intra- and inter-specific variation in petal number. We found that a cis-regulatory change in the homeotic gene APETALA1 caused petal number to be decanalized in Cardamine hirsuta, allowing the phenotypic expression of various QTL influencing petal number at the intraspecific scale.

Previous research: LEAFY evolution

LEAFY is a transcription factor crucial for floral development in the angiosperms. However it is also present in other groups of plants that do not flower, such as gymnosperms, ferns, mosses and some algae. During my PhD in the group of François Parcy, I studied the evolution of the DNA-binding specificy of LEAFY. We found that, although the LEAFY gene was mostly kept as a single copy gene for 800 million years of evolution, the LEAFY protein managed to change specificity at least two times, thanks to an intermediate with a relaxed specificity.


2023: Habilitation à Diriger des Recherches (HDR) from the Université Claude Bernard Lyon 1

2013 - 2017: Post-doctoral research fellow with Angela Hay at the Max Planck Institute for Plant Breeding Research (MPIPZ), Cologne, Germany

2009 - 2013: PhD in plant biology with François Parcy at the Laboratory for Plant and Cell Physiology (LPCV), Grenoble, France

2007 - 2009: Master "Biosciences" (ENS de Lyon)

2008: Life and Earth Sciences Agrégation obtained

2006: Bachelor "Cell and Molecular Biology" (ENS de Lyon)


2023 - 2026: Supervision of 1 PhD student (Emma Désert), co-direction with Daniel Bouyer (RDP lab)

2020 - 2023: Supervision of 1 PhD student (Quentin Cavallini-Speisser)

2020 - 2021: Management of 1 assistant engineer (AI, Jordan Brun)

2013 - 2020: Supervision of 1 bachelor and 3 master students, co-supervision of 1 PhD student

2009 - 2013: Teaching at the Université Grenoble-Alpes for > 260 hours. Practicals, exercices and lectures, from bachelor to master level. Plant physiology, genetics and development, ecology, organismal biology, introduction to biology.


2022 - today: Scientific coordinator for the Equipex+ consortium Spatial-Cell-ID for spatial transcriptomics, together with Yad Ghavi-Helm and Jonathan Enriquez (IGFL).

2021 - today: Member of the organizing comittee for the meeting EvoLyon (

2018 - today: PhD jury member for Léa Rambaud (2018, RDP), Pierre Galipot (2021, MNHN, Paris), Nathalie Bouré (2021, IJPB, Université Paris Saclay), Jeanne Loue-Manifel (2021, RDP), Antonin Galien (2022, LPCV Grenoble), Pauline Delpeuch (2023, ESE Université Paris Saclay).

2021: Nominated jury member for the CNRS selection of researchers, section 23 (Integrative Plant Biology).

2020: Panel member for the DFG research unit ICIPS (Innovation and Coevolution In Plant Sexual reproduction).

2019 - onwards: Gender equality representative for the RDP lab.

I am also a member of several PhD advisory committees (LPCV, RDP, IJPB, LIPMe), I have a regular paper reviewing activity ( and I participate to several science popularization events (Fête de la Science, Déclics, science popularization conferences at Université Ouverte, lab visits for secondary school students).


(Invited) MeMoDEvo Symposium, Paris, France (12-13 December 2022). "Petal morphology and its evolution: a matter of layers".

17th World Petunia Days, Milan, Italy (4-7 July 2019). "Dissecting petunia petal development".

(Invited) SFR Biosciences Days, Sainte-Foy-lès-Lyon, France (19 June 2018). "Genetic basis of petal number robustness".

Euro Evo Devo 2016, Uppsala, Sweden (26-29 July 2016). “Genetic basis of petal number variation in Cardamine hirsuta”.

New model systems for linking evolution and ecology, EMBL Heidelberg, Germany (8-11 May 2016). “Petal number variation in Cardamine hirsuta”.

Euro Evo Devo 2014, Vienna, Austria (22-25 July 2014). “Evolution of the floral regulator LEAFY in the green lineage”.

Molecular mechanisms controlling flower development, Giens, France (8-12 June 2013). “800 million years of LEAFY evolution”.



Chopy M, Cavallini Speisser Q, Chambrier P, Morel P, Just J, Hugouvieux V, Rodrigues Bento S, Zubieta C, Vandenbussche M, Monniaux M. Cell layer-specific expression of the homeotic MADS-box transcription factor PhDEF contributes to modular petal morphogenesis in petunia. The Plant Cell. doi: 10.1093/plcell/koad258.

Monniaux M, Vandenbussche M. Flower Development in the Solanaceae. Methods Mol Biol. 2686:39-58. doi: 10.1007/978-1-0716-3299-4_2.

Monniaux M. Unusual suspects in flower color evolution. Science. 379(6632):534-535. doi: 10.1126/science.adg2774.


Cavallini-Speisser Q, Morel P, Monniaux M. Petal cellular identities. Frontiers in Plant Science. 12:2430. doi: 10.3389/fpls.2021.745507.


Morel P, Chambrier P, Boltz V, Chamot S, Rozier F, Rodrigues Bento S, Trehin C, Monniaux M, Zethof J, Vandenbussche M. Divergent Functional Diversification Patterns in the SEP/AGL6/AP1 MADS-Box Transcription Factor Superclade. The Plant Cell. 31(12):3033-3056. doi: 10.1105/tpc.19.00162.


Monniaux M, Vandenbussche M. How to Evolve a Perianth: A Review of Cadastral Mechanisms for Perianth Identity. Frontiers in Plant Science. 29;9:1573. doi: 10.3389/fpls.2018.01573.

Monniaux M*, Pieper B*, McKim SM, Routier-Kierzkowska AL, Kierzkowski D, Smith RS, Hay A. The role of APETALA1 in petal number robustness. Elife. 18;7. doi: 10.7554/eLife.39399.


McKim SM, Routier-Kierzkowska AL, Monniaux M, Kierzkowski D, Pieper B, Smith RS, Tsiantis M, Hay A. Seasonal Regulation of Petal Number. Plant Physiology. 175(2):886-903. doi: 10.1104/pp.17.00563.

Moyroud E, Monniaux M, Thévenon E, Dumas R, Scutt CP, Frohlich MW, Parcy F. A link between LEAFY and B-gene homologues in Welwitschia mirabilis sheds light on ancestral mechanisms prefiguring floral development. New Phytologist. 216(2):469-481. doi: 10.1111/nph.14483.

Monniaux M, McKim SM, Cartolano M, Thévenon E, Parcy F, Tsiantis M, Hay A. Conservation vs divergence in LEAFY and APETALA1 functions between Arabidopsis thaliana and Cardamine hirsuta. New Phytologist. 216(2):469-481. doi: 10.1111/nph.14419.


Monniaux M, Hay A. Cells, walls, and endless forms. Current Opinion in Plant Biology. 34:114-121. doi: 10.1016/j.pbi.2016.10.010.

Monniaux M*, Pieper B*, Hay A. Stochastic variation in Cardamine hirsuta petal number. Annals of Botany. 117(5):881-7. doi: 10.1093/aob/mcv131.

Pieper B, Monniaux M, Hay A. The genetic architecture of petal number in Cardamine hirsuta. New Phytologist. 209(1):395-406. doi: 10.1111/nph.13586.


Sayou C*, Monniaux M*, Nanao MH*, Moyroud E*, Brockington SF, Thévenon E, Chahtane H, Warthmann N, Melkonian M, Zhang Y, Wong GK, Weigel D, Parcy F, Dumas R. A Promiscuous Intermediate Underlies the Evolution of LEAFY DNA Binding Specificity. Science. 343(6171):645-8. doi: 10.1126/science.1248229.


Chahtane H, Vachon G, Le Masson M, Thévenon E, Périgon S, Mihajlovic N, Kalinina A, Michard R, Moyroud E, Monniaux M, Sayou C, Grbic V, Parcy F, Tichtinsky G. A variant of LEAFY reveals its capacity to stimulate meristem development by inducing RAX1. The Plant Journal. 74(4):678-89. doi: 10.1111/tpj.12156.


Moyroud E, Minguet EG, Ott F, Yant L, Posé D, Monniaux M, Blanchet S, Bastien O, Thévenon E, Weigel D, Schmid M, Parcy F. Prediction of regulatory interactions from genome sequences using a biophysical model for the Arabidopsis LEAFY transcription factor. The Plant Cell. 23(4):1293-306. doi: 10.1105/tpc.111.083329.

Winter CM, Austin RS, Blanvillain-Baufumé S, Reback MA, Monniaux M, Wu MF, Sang Y, Yamaguchi A, Yamaguchi N, Parker JE, Parcy F, Jensen ST, Li H, Wagner D. LEAFY target genes reveal floral regulatory logic, cis motifs, and a link to biotic stimulus response. Developmental Cell. 20(4):430-43. doi: 10.1016/j.devcel.2011.03.019.


Moyroud E, Kusters E, Monniaux M, Koes R, Parcy F. LEAFY blossoms. Trends in Plant Science. 15(6):346-52. doi: 10.1016/j.tplants.2010.03.007.