title: PsbS interactions involved in the activation of energy dissipation in Arabidopsis.
abstract: The non-photochemical quenching of light energy as heat (NPQ) is an important photoprotective mechanism that is activated in plants when light absorption exceeds the capacity of light utilization in photosynthesis. The PsbS protein plays a central role in this process and is supposed to activate NPQ through specific, light-regulated interactions with photosystem (PS) II antenna proteins. However, NPQ-specific interaction partners of PsbS in the thylakoid membrane are still unknown. Here, we have determined the localization and protein interactions of PsbS in thylakoid membranes in the NPQ-inactive (dark) and NPQ-active (light) states. Our results corroborate a localization of PsbS in PSII supercomplexes and support the model that the light activation of NPQ is based on the monomerization of dimeric PsbS and a light-induced enhanced interaction of PsbS with Lhcb1, the major component of trimeric light-harvesting complexes in PSII.
authors.affiliation: Plant Biochemistry, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: Viviana
authors.initials: V
authors.lastname: Correa-Galvis
authors.affiliation: Molecular Proteomics Laboratory, Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: Gereon
authors.identifier: 0000-0003-2448-0611
authors.initials: G
authors.lastname: Poschmann
authors.affiliation: Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466 Gatersleben, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Melzer
authors.affiliation: Molecular Proteomics Laboratory, Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Stühler
authors.affiliation: Plant Biochemistry, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Jahns
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D003624:Darkness; D004734:Energy Metabolism; D005453:Fluorescence; D008027:Light; D045342:Light-Harvesting Protein Complexes / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D008968:Molecular Conformation; D009154:Mutation; D010788:Photosynthesis / Q000528:radiation effects; D045332:Photosystem II Protein Complex / Q000235:genetics / Q000378:metabolism*; D025941:Protein Interaction Mapping; D020524:Thylakoids / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D045342:Light-Harvesting Protein Complexes; C489731:NPQ4 protein, Arabidopsis; D045332:Photosystem II Protein Complex; D002734:Chlorophyll