9IMN

Cryo-EM structure of a TEF30-associated intermediate PSII core dimer complex, type I, from Chlamydomonas reinhardtii

Summary for 9IMN

• Entry DOI: 10.2210/pdb9imn/pdb
• EMDB information: 60694
• Descriptor: Photosystem II protein D1, Photosystem II reaction center protein K, Photosystem II reaction center protein L, ... (29 entities in total)
• Functional Keywords: photosystem ii, psii repair, psii assembly, psii intermediate, tef30, photosynthesis
• Biological source: Chlamydomonas reinhardtii; More
• Total number of polymer chains: 34
• Total formula weight: 623407.62

Authors

Wang, Y.,Wang, C.,Li, A.,Liu, Z. (deposition date: 2024-07-03, release date: 2025-05-14, Last modification date: 2025-07-23)

Primary citation

Wang, Y.,Wang, C.,Li, A.,Liu, Z.
Roles of multiple TEF30-associated intermediate complexes in the repair and reassembly of photosystem II in Chlamydomonas reinhardtii.
Nat.Plants, 2025

PubMed Abstract: During oxygenic photosynthesis, photosystem II (PSII) uses light energy for oxidizing water and reducing plastoquinone. It is susceptible to photodamage, and the damaged PSII is repaired through a sophisticated biological process assisted by numerous auxiliary proteins. Here we report the cryogenic electron microscopy structures of four PSII-repair complexes from Chlamydomonas reinhardtii associated with the Thylakoid Enriched Fraction 30 (TEF30, an orthologue of plant MET1) protein-namely, a TEF30-PSII core monomer (TEF30-C), two types of TEF30-PSII core dimers (types I and II, TEF30-C-I and TEF30-C-II) and a TEF30-CS-type PSII-LHCII supercomplex (TEF30-CS; S, strongly associated light-harvesting complex II trimer). TEF30 mediates the assembly of CP43 with the RC47 module by clamping on the stromal surfaces and prevents the premature association of peripheral antennae with PSII-C. In the transition from TEF30-C-I to TEF30-C-II, TEF30-CS and mature CS, one PSII core slides along the dimerization interface against the adjacent one by 22-35 Å, generating a zigzagged surface for accommodating the peripheral antennae. These results suggest that the PSII repair process undergoes multiple TEF30-mediated intermediate states to form intact PSII-LHCII supercomplexes.

PubMed: 40579438
DOI: 10.1038/s41477-025-02036-3

Experimental method

ELECTRON MICROSCOPY (2.97 Å)