1. A new, unquenched intermediate of LHCII
- Author
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Li, Fei, Liu, Cheng, Streckaite, Simona, Yang, Chunhong, Xu, Pengqi, Llansola-Portoles, Manuel J., Ilioaia, Cristian, Pascal, Andrew A., Croce, Roberta, Robert, Bruno, Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire Bioénergétique Membranaire et Stress (LBMS), Département Biochimie, Biophysique et Biologie Structurale (B3S), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Biophysics Photosynthesis/Energy, and LaserLaB - Energy
- Subjects
LHCII ,NPQ ,α-DM, n-dodecyl-α-D-maltoside ,[SDV]Life Sciences [q-bio] ,β-DM-LHCII, LHCII purified with n-dodecyl-β-D-maltoside ,Arabidopsis ,Light-Harvesting Protein Complexes ,light-harvesting complex ,resonance Raman ,α-DM-LHCII, LHCII purified with n-dodecyl-α-D-maltoside ,β-DM, n-dodecyl-β-D-maltoside ,NPQ, non-photochemical quenching ,SDG 7 - Affordable and Clean Energy ,skin and connective tissue diseases ,LHC, light harvesting complex ,light harvesting complex ,Arabidopsis Proteins ,Photosystem II Protein Complex ,photoprotection ,Chl a, chlorophyll a ,Qy, light absorption due to electronic transition along the y-axis of the chlorophyll molecule ,qE, energy dependent component of NPQ ,Chl b, chlorophyll b ,sense organs ,LHCII, light harvesting complex II ,Research Article - Abstract
When plants are exposed to high-light conditions, the potentially harmful excess energy is dissipated as heat, a process called non-photochemical quenching. Efficient energy dissipation can also be induced in the major light-harvesting complex of photosystem II (LHCII) in vitro, by altering the structure and interactions of several bound cofactors. In both cases, the extent of quenching has been correlated with conformational changes (twisting) affecting two bound carotenoids, neoxanthin, and one of the two luteins (in site L1). This lutein is directly involved in the quenching process, whereas neoxanthin senses the overall change in state without playing a direct role in energy dissipation. Here we describe the isolation of an intermediate state of LHCII, using the detergent ndodecyl-α-D-maltoside, which exhibits the twisting of neoxanthin (along with changes in chlorophyll-protein interactions), in the absence of the L1 change or corresponding quenching. We demonstrate that neoxanthin is actually a reporter of the LHCII environment-probably reflecting a large-scale conformational change in the protein-whereas the appearance of excitation energy quenching is concomitant with the configuration change of the L1 carotenoid only, reflecting changes on a smaller scale. This unquenched LHCII intermediate, described here for the first time, provides for a deeper understanding of the molecular mechanism of quenching.
- Published
- 2021