{"title":"Roles of multiple TEF30-associated intermediate complexes in the repair and reassembly of photosystem II in Chlamydomonas reinhardtii","authors":"Yidi Wang, Chenxi Wang, Anjie Li, Zhenfeng Liu","doi":"10.1038/s41477-025-02036-3","DOIUrl":null,"url":null,"abstract":"<p>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 <i>Chlamydomonas reinhardtii</i> 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<sub>2</sub>-C<sub>2</sub>-I and TEF30<sub>2</sub>-C<sub>2</sub>-II) and a TEF30-C<sub>2</sub>S-type PSII–LHCII supercomplex (TEF30-C<sub>2</sub>S; 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<sub>2</sub>-C<sub>2</sub>-I to TEF30<sub>2</sub>-C<sub>2</sub>-II, TEF30-C<sub>2</sub>S and mature C<sub>2</sub>S<sub>2</sub>, 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.</p>","PeriodicalId":18904,"journal":{"name":"Nature Plants","volume":"57 1","pages":""},"PeriodicalIF":15.8000,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nature Plants","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1038/s41477-025-02036-3","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 0
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, TEF302-C2-I and TEF302-C2-II) and a TEF30-C2S-type PSII–LHCII supercomplex (TEF30-C2S; 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 TEF302-C2-I to TEF302-C2-II, TEF30-C2S and mature C2S2, 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.
期刊介绍:
Nature Plants is an online-only, monthly journal publishing the best research on plants — from their evolution, development, metabolism and environmental interactions to their societal significance.