biostudies-literatureUnknown16Jiao YPhotosystem II Subunit S (PsbS) is a critical regulator of non-photochemical quenching (NPQ), which is a protective mechanism triggered to dissipate excess light energy as heat and prevent photodamage. However, the molecular basis of how PsbS interact with partner proteins to regulate NPQ remains unclear. In this study, we employed proximity labeling to identify PsbS interaction proteins <i>in situ</i> in living cells of Arabidopsis leaves via biotinylation during NPQ. Arabidopsis plants stably expressing PsbS constructs fused to proximity labeling enzyme TurboID were generated and the biotinylated proteomes were analyzed by liquid chromatography-mass spectrometry. The interactomes of PsbS under dark and under light were generated, which not only confirmed several known PsbS-interacting prFrontiers in plant science1705804https://www.ebi.ac.uk/biostudies/studies/S-EPMC12864446biostudies-literatureIdentification of PsbS binding proteins in &lt;i&gt;Arabidopsis thaliana&lt;/i&gt; leaf chloroplasts under high light using TurboID-based proximity labeling.PMC12864446Dou YZheng HZhu XGJiao YWang LfalseIdentification of PsbS binding proteins in &lt;i&gt;Arabidopsis thaliana&lt;/i&gt; leaf chloroplasts under high light using TurboID-based proximity labeling.Photosystem II Subunit S (PsbS) is a critical regulator of non-photochemical quenching (NPQ), which is a protective mechanism triggered to dissipate excess light energy as heat and prevent photodamage. However, the molecular basis of how PsbS interact with partner proteins to regulate NPQ remains unclear. In this study, we employed proximity labeling to identify PsbS interaction proteins <i>in situ</i> in living cells of Arabidopsis leaves via biotinylation during NPQ. Arabidopsis plants stably expressing PsbS constructs fused to proximity labeling enzyme TurboID were generated and the biotinylated proteomes were analyzed by liquid chromatography-mass spectrometry. The interactomes of PsbS under dark and under light were generated, which not only confirmed several known PsbS-interacting pr2025-01-01T00:00:00Z20252026-07-15T06:54:57.442Z2026-06-30T03:31:18.434ZS-EPMC128644464164077510.3389/fpls.2025.1705804