title: TEF30 Interacts with Photosystem II Monomers and Is Involved in the Repair of Photodamaged Photosystem II in Chlamydomonas reinhardtii.
abstract: The remarkable capability of photosystem II (PSII) to oxidize water comes along with its vulnerability to oxidative damage. Accordingly, organisms harboring PSII have developed strategies to protect PSII from oxidative damage and to repair damaged PSII. Here, we report on the characterization of the THYLAKOID ENRICHED FRACTION30 (TEF30) protein in Chlamydomonas reinhardtii, which is conserved in the green lineage and induced by high light. Fractionation studies revealed that TEF30 is associated with the stromal side of thylakoid membranes. By using blue native/Deriphat-polyacrylamide gel electrophoresis, sucrose density gradients, and isolated PSII particles, we found TEF30 to quantitatively interact with monomeric PSII complexes. Electron microscopy images revealed significantly reduced thylakoid membrane stacking in TEF30-underexpressing cells when compared with control cells. Biophysical and immunological data point to an impaired PSII repair cycle in TEF30-underexpressing cells and a reduced ability to form PSII supercomplexes after high-light exposure. Taken together, our data suggest potential roles for TEF30 in facilitating the incorporation of a new D1 protein and/or the reintegration of CP43 into repaired PSII monomers, protecting repaired PSII monomers from undergoing repeated repair cycles or facilitating the migration of repaired PSII monomers back to stacked regions for supercomplex reassembly.
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.).
authors.forename: Ligia Segatto
authors.identifier: http://orcid.org/0000-0003-3599-4669
authors.initials: LS
authors.lastname: Muranaka
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.).
authors.forename: Mark
authors.identifier: http://orcid.org/0000-0002-6604-2778
authors.initials: M
authors.lastname: Rütgers
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.).
authors.forename: Sandrine
authors.initials: S
authors.lastname: Bujaldon
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.).
authors.forename: Anja
authors.identifier: http://orcid.org/0000-0002-1092-2485
authors.initials: A
authors.lastname: Heublein
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.).
authors.forename: Stefan
authors.initials: S
authors.lastname: Geimer
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.).
authors.forename: Francis-André
authors.identifier: http://orcid.org/0000-0003-2638-7840
authors.initials: FA
authors.lastname: Wollman
authors.affiliation: Molekulare Biotechnologie und Systembiologie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany (L.S.M., M.R., M.S.);Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, Institut de Biologie Physico-Chimique, Unité Mixte de Recherche Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, 7141 Paris, France (S.B., F.-A.W.); andZellbiologie/Elektronenmikroskopie, Universität Bayreuth, D-95440 Bayreuth, Germany (A.H., S.G.) schroda@bio.uni-kl.de.
authors.forename: Michael
authors.identifier: http://orcid.org/0000-0001-6872-0483
authors.initials: M
authors.lastname: Schroda
mesh_terms: D016825:Chlamydomonas reinhardtii / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects / Q000648:ultrastructure; D008027:Light; D008954:Models, Biological; D045332:Photosystem II Protein Complex / Q000235:genetics / Q000378:metabolism*; D020524:Thylakoids / Q000378:metabolism / Q000528:radiation effects / Q000648:ultrastructure
chemical_list: D045332:Photosystem II Protein Complex