title: Structural adaptation of the plant protease Deg1 to repair photosystem II during light exposure.
abstract: Deg1 is a chloroplastic protease involved in maintaining the photosynthetic machinery. Structural and biochemical analyses reveal that the inactive Deg1 monomer is transformed into the proteolytically active hexamer at acidic pH. The change in pH is sensed by His244, which upon protonation, repositions a specific helix to trigger oligomerization. This system ensures selective activation of Deg1 during daylight, when acidification of the thylakoid lumen occurs and photosynthetic proteins are damaged.
authors.affiliation: Research Institute of Molecular Pathology (IMP), Vienna, Austria.
authors.forename: Juliane
authors.initials: J
authors.lastname: Kley
authors.forename: Bastian
authors.initials: B
authors.lastname: Schmidt
authors.forename: Boril
authors.initials: B
authors.lastname: Boyanov
authors.forename: Peggy C
authors.initials: PC
authors.lastname: Stolt-Bergner
authors.forename: Rebecca
authors.initials: R
authors.lastname: Kirk
authors.forename: Michael
authors.initials: M
authors.lastname: Ehrmann
authors.forename: Ronit R
authors.initials: RR
authors.lastname: Knopf
authors.forename: Leah
authors.initials: L
authors.lastname: Naveh
authors.forename: Zach
authors.initials: Z
authors.lastname: Adam
authors.forename: Tim
authors.initials: T
authors.lastname: Clausen
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000378:metabolism*; D018360:Crystallography, X-Ray; D006863:Hydrogen-Ion Concentration; D008027:Light; D008954:Models, Biological; D008958:Models, Molecular; D045332:Photosystem II Protein Complex / Q000378:metabolism*; D011487:Protein Conformation; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D012697:Serine Endopeptidases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D045332:Photosystem II Protein Complex; C520844:Deg1 protein, Arabidopsis; D012697:Serine Endopeptidases