title: The structure of photosystem II in Arabidopsis: localization of the CP26 and CP29 antenna complexes.
abstract: A genetic approach has been adopted to investigate the organization of the light-harvesting proteins in the photosystem II (PSII) complex in plants. PSII membrane fragments were prepared from wild-type Arabidopis thaliana and plants expressing antisense constructs to Lhcb4 and Lhcb5 genes, lacking CP29 and CP26, respectively (Andersson et al. (2001) Plant Cell 13, 1193-1204). Ordered PS II arrays and PS II supercomplexes were isolated from the membranes of plants lacking CP26 but could not be prepared from those lacking CP29. Membranes and supercomplexes lacking CP26 were less stable than those prepared from the wild type. Transmission electron microscopy aided by single-particle image analysis was applied to the ordered arrays and the isolated PSII complexes. The difference between the images obtained from wild type and antisense plants showed the location of CP26 to be near CP43 and one of the light-harvesting complex trimers. Therefore, the location of the CP26 within PSII was directly established for the first time, and the location of the CP29 complex was determined by elimination. Alterations in the packing of the PSII complexes in the thylakoid membrane also resulted from the absence of CP26. The minor light-harvesting complexes each have a unique location and important roles in the stabilization of the oligomeric PSII structure.
authors.affiliation: Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
authors.forename: Alevtyna E
authors.initials: AE
authors.lastname: Yakushevska
authors.forename: Wilko
authors.initials: W
authors.lastname: Keegstra
authors.forename: Egbert J
authors.initials: EJ
authors.lastname: Boekema
authors.forename: Jan P
authors.initials: JP
authors.lastname: Dekker
authors.forename: Jenny
authors.initials: J
authors.lastname: Andersson
authors.forename: Stefan
authors.initials: S
authors.lastname: Jansson
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Ruban
authors.forename: Peter
authors.initials: P
authors.lastname: Horton
mesh_terms: D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D061146:Chlorophyll Binding Proteins; D002850:Chromatography, Gel; D007091:Image Processing, Computer-Assisted; D045342:Light-Harvesting Protein Complexes; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D013329:Structure-Activity Relationship; D020524:Thylakoids / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D029681:Arabidopsis Proteins; C069660:CP29 light harvesting complex; D061146:Chlorophyll Binding Proteins; C490432:LHCB5 protein, Arabidopsis; D045342:Light-Harvesting Protein Complexes; D046911:Macromolecular Substances; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins