title: High light stimulates Deg1-dependent cleavage of the minor LHCII antenna proteins CP26 and CP29 and the PsbS protein in Arabidopsis thaliana.
abstract: The chloroplast Deg1 protein performs proteolytic cleavage of the photodamaged D1 protein of the photosystem II (PSII) reaction center, PSII extrinsic subunit PsbO and the soluble electron carrier plastocyanin. Using biochemical, immunological and mass spectrometry approaches we showed that the heterogeneously expressed Deg1 protease from Arabidopsis thaliana can be responsible for the degradation of the monomeric light-harvesting complex antenna subunits of PSII (LHCII), CP26 and CP29, as well as PSII-associated PsbS (CP22/NPQ4) protein. The results may indicate that cytochrome b                         (6) protein and two previously unknown thylakoid proteins, Ptac16 and an 18.3-kDa protein, may be the substrates for Deg1. The interaction of Deg1 with the PsbS protein and the minor LHCII subunits implies its involvement in the regulation of both excess energy dissipation and state transition adaptation processes.
authors.affiliation: Department of Molecular Plant Physiology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland. maximus@biol.uw.edu.pl
authors.forename: Maksymilian
authors.initials: M
authors.lastname: Zienkiewicz
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Ferenc
authors.forename: Wioleta
authors.initials: W
authors.lastname: Wasilewska
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Romanowska
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D002364:Caseins / Q000378:metabolism; D061146:Chlorophyll Binding Proteins / Q000235:genetics / Q000378:metabolism; D060365:Chloroplast Proteins / Q000235:genetics / Q000378:metabolism; D045303:Cytochromes b / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015151:Immunoblotting; D008027:Light; D045342:Light-Harvesting Protein Complexes / Q000235:genetics / Q000378:metabolism; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010777:Photochemistry; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism / Q000528:radiation effects; D025941:Protein Interaction Mapping; D059748:Proteolysis; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D013379:Substrate Specificity; D060431:Thylakoid Membrane Proteins / Q000235:genetics / Q000378:metabolism; D020524:Thylakoids / Q000187:drug effects / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002364:Caseins; D061146:Chlorophyll Binding Proteins; D060365:Chloroplast Proteins; C490432:LHCB5 protein, Arabidopsis; D045342:Light-Harvesting Protein Complexes; C489731:NPQ4 protein, Arabidopsis; D045332:Photosystem II Protein Complex; C529074:RBP29 protein, Arabidopsis; D011994:Recombinant Proteins; D012261:Ribonucleoproteins; D060431:Thylakoid Membrane Proteins; D045303:Cytochromes b; C520844:Deg1 protein, Arabidopsis; D012697:Serine Endopeptidases