Theme 1: Biogenesis and Function of the Photosynthetic Apparatus

Objective:

We aim to deepen our understanding of the biogenesis and function of the photosynthetic apparatus, particularly in diatoms and Chlamydomonas. A number of unresolved questions remains regarding the multiple regulatory feedbacks governing every aspect of chloroplast development and photosynthetic function. Moreover, despite a plethora of structures of all major photosynthetic complexes currently available, several electron transfer cofactors have unknown function and poorly understood biogenesis pathways. To tackle these issues, the lab employs genetic tools and comparative approaches, aiming to define the mechanisms governing plastid gene expression, biogenesis of photosynthetic complex, and regulation of light harvesting and photoprotection; through a collaborative approach, we want to uncover commonalities and differences between the green and red/brown lineages. All of these activities are strongly supported by the Genetic and Biophysical resources of the laboratory, see section Resource Centres.

Key Research Areas:

1. Plastid Biogenesis

  •  Control of Chloroplast Gene Expression
  • Protein Assembly and Degradation
  • Diatom Plastid Biogenesis and Genetics

2. Photosynthetic Function

  • Light Harvesting and Photoprotection
  • Electron and Ion Transport
  • Comparative Physiology

Conclusion:

This research aims to uncover the fundamental mechanisms governing photosynthesis and explore its evolutionary diversity, contributing to our understanding of the natural world.

Recent Publications:

Croteau D, Jaubert M, Falciatore A and Bailleul B (2025) Pennate diatoms make Non Photochemical Quenching as simple as possible but not simpler, Nature Comms 16(1):2385 – https://doi.org/10.1038/s41467-025-57298-4

Levin G, Yasmin M, Liran O, Hanna R, Kleifeld O, Horev G, Wollman FA, Schuster G, Nawrocki WJ. – Processes independent of nonphotochemical quenching protect a high-light-tolerant desert alga from oxidative stress. Plant Physiology. 2025 Jan;197(1):kiae608. – https://doi.org/10.1093/plphys/kiae608

Tada K, Yamagata K, Koyama K, Sellés J, Boussac A, Sugiura MDifferential effects of the D1/S264V mutation in photosystem II with either PsbA1 or PsbA3 on QB, non-heme Iron, and the associated hydrogen-bond network – 2025 – BBA 1866(3):149557 – https://doi.org/10.1016/j.bbabio.2025.149557

Lang J, König K, Venn B, Zeilfelder S, Ostermeier M, Spaniol B, Lara Spaniol L, Sommer F, Mustas M, Geimer S, Fürtges T, Brzezowski P, Zabret J, Wollman F-A, Nowacyzk M, Scheuring D, Rudack T, Mühlhaus T, Choquet Y, and Schroda M –Complexome profiling of the Chlamydomonas psb28 mutant reveals THYLAKOID ENRICHED FRACTION 5 as an early PS II assembly factor – 2025 – The Plant Cell, 37(6):koaf055 – https://doi.org/10.1093/plcell/koaf055

Boussac A, Sugiura M, Nakamura M, Nagao R, Noguchi T, Viola S, Rutherford AW, Sellés J – Absorption changes in Photosystem II in the Soret band region upon the formation of the chlorophyll cation radical [PD1PD2]+ – 2024 – Photosynth Res 162(2-3):211-223 – https://doi.org/10.1007/s11120-023-01049-3

Sellés, J.; Alric, J.; Rutherford, A. W.; Davis, G. A. & Viola, S. – In vivo ElectroChromic Shift measurements of photosynthetic activity in far-red absorbing cyanobacteria – 2024 – Biochimica et Biophysica Acta (BBA) – Bioenergetics, 2024, 1865, 149502 – https://doi.org/10.1016/j.bbabio.2024.149502

Boussac A, Sugiura M, Sellés J – Probing the proton release by Photosystem II in the S1 to S2 high-spin transition – 2022 – BBA 1863(5):148546. – https://doi.org/10.1016/j.bbabio.2022.148546

Wietrzynski W, Traverso E, Wollman F-A, Wostrikoff K (2021) The state of oligomerization of Rubisco controls the rate of synthesis of the Rubisco large subunit in Chlamydomonas reinhardtii, The Plant Cell, 33(5):1706-1727 – https://doi.org/10.1093/plcell/koab061

Ozawa S, Cavaiuolo M, Jarrige D, Kuras R, Rutgers M, Eberhard S, Drapier D, Wollman F-A, Choquet Y (2020) The OPR Protein MTHI1 Controls the Expression of Two Different Subunits of ATP Synthase CFo in Chlamydomonas reinhardtii, Plant Cell, 32(4):1179-1203 – https://doi.org/10.1105/tpc.19.00770

PhD manuscripts:

ZAOUI Amel (2024) OPR-RAP proteins in organellar gene expression regulation by the nucleus in Chlamydomonas reinhardtii. Thèse de doctorat, Sorbonne Université, Paris.

CROTEAU Dany (2024) NPQ in pennate diatoms: a simple phenomenon and tool to probe multi-level orchestration of photosynthetic regulations. Thèse de doctorat, Sorbonne Université, Paris.

BUJALDON Sandrine (2023) Les antennes photosynthétiques chez Chlamydomonas reinhardtii : biogénèse, fonction et régulation. Thèse de doctorat en Biologie, Sorbonne Université, Paris.

RODRIGUES AZEVEDO Marcio (2023) Les transports d’ions à travers la membrane du thylacoïde chez Chlamydomonas reinhardtii. Thèse de doctorat, Université Paris-Saclay.

MUSTAS Matthieu (2023) Régulations de l’expression des gènes du Chloroplaste chez Chlamydomonas reinhardtii : ARN et protéine. Thèse de doctorat, Sorbonne Université, Paris.

JARRIGE Domitille (2019) Déchiffrer le “code OPR” pour une meilleure compréhension du rôle physiologique des protéines OPR. Thèse de doctorat en Biologie, Sorbonne Université, Paris.