A new, unquenched intermediate of LHCII

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 stru...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 2021-01, Vol.296, p.100322-100322, Article 100322
Main Authors: Li, Fei, Liu, Cheng, Streckaite, Simona, Yang, Chunhong, Xu, Pengqi, Llansola-Portoles, Manuel J., Ilioaia, Cristian, Pascal, Andrew A., Croce, Roberta, Robert, Bruno
Format: Article
Language:English
Subjects:
LHCII
Life Sciences
light-harvesting complex
NPQ
photoprotection
resonance Raman
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary: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 n-dodecyl-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.
ISSN:0021-9258
1083-351X
DOI:10.1016/j.jbc.2021.100322