title: The structures of Arabidopsis Deg5 and Deg8 reveal new insights into HtrA proteases.
abstract: Plant Deg5 and Deg8 are two members of the HtrA proteases, a family of oligomeric serine endopeptidases that are involved in a variety of protein quality-control processes. These two HtrA proteases are located in the thylakoid lumen and participate in high-light stress responses by collaborating with other chloroplast proteins. Deg5 and Deg8 degrade photodamaged D1 protein of the photosystem II reaction centre, allowing its in situ replacement. Here, the crystal structures of Arabidopsis thaliana Deg5 (S266A) and Deg8 (S292A) are reported at 2.6 and 2.0 Å resolution, respectively. The Deg5 trimer contains two calcium ions in a central channel, suggesting a link between photodamage control and calcium ions in chloroplasts. Previous structures of HtrA proteases have indicated that their regulation usually requires C-terminal PDZ domain(s). Deg5 is unique in that it contains no PDZ domain and the trimeric structure of Deg5 (S266A) reveals a novel catalytic triad conformation. A similar triad conformation is observed in the hexameric structure of the single PDZ-domain-containing Deg8 (S292A). These findings suggest a novel activation mechanism for plant HtrA proteases and provide structural clues to their function in light-stress response.
authors: Laboratory of Non-coding RNA, Institute of Biophysics, Chinese Academy of Sciences, 5 Datun Road, Chaoyang District, Beijing 100101, People's Republic of China.
authors: Wei
authors: W
authors: Sun
authors: Feng
authors: F
authors: Gao
authors: Haitian
authors: H
authors: Fan
authors: Xiaoyue
authors: X
authors: Shan
authors: Renhua
authors: R
authors: Sun
authors: Lin
authors: L
authors: Liu
authors: Weimin
authors: W
authors: Gong
mesh_terms: D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D020134:Catalytic Domain; D002736:Chloroplasts / Q000378:metabolism; D018360:Crystallography, X-Ray; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000378:metabolism; D006860:Hydrogen Bonding; D008027:Light; D008958:Models, Molecular; D054731:PDZ Domains; D033903:Periplasmic Proteins / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D012697:Serine Endopeptidases / Q000737:chemistry* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D006360:Heat-Shock Proteins; D033903:Periplasmic Proteins; C576657:Deg8 protein, Arabidopsis; C061682:DegP protease; C436319:SPPA protein, Arabidopsis; D012697:Serine Endopeptidases; D002118:Calcium
keywords: PDZ domains; oligomerization; protease–chaperones; protein quality control
references: Acta Crystallogr D Biol Crystallogr. 2011 Apr;67(Pt 4):355-67
references: 21460454
references: Cell. 2007 Nov 2;131(3):572-83
references: 17981123
references: Nat Struct Mol Biol. 2011 Jun;18(6):728-31
references: 21532594
references: Annu Rev Genet. 2008;42:463-515
references: 18983262
references: Nucleic Acids Res. 2008 Jan;36(Database issue):D320-5
references: 17991683
references: Plant J. 2010 Apr;62(2):240-9
references: 20088900
references: Mol Cell. 2002 Sep;10(3):443-55
references: 12408815
references: Acta Crystallogr D Biol Crystallogr. 2010 Apr;66(Pt 4):486-501
references: 20383002
references: Cell. 2011 Apr 1;145(1):67-78
references: 21458668
references: J Biol Chem. 2012 Jul 13;287(29):24721-33
references: 22549771
references: Nat Struct Mol Biol. 2011 Mar;18(3):386-8
references: 21297635
references: Nat Struct Biol. 2002 Jun;9(6):436-41
references: 11967569
references: J Exp Bot. 2012 Feb;63(4):1525-42
references: 22200666
references: Cell. 2004 May 14;117(4):483-94
references: 15137941
references: Acta Crystallogr D Biol Crystallogr. 2010 Jan;66(Pt 1):22-5
references: 20057045
references: Plant Cell. 2007 Apr;19(4):1347-61
references: 17449806
references: Acta Crystallogr Sect F Struct Biol Cryst Commun. 2012 Jul 1;68(Pt 7):839-41
references: 22750879
references: Nature. 2002 Mar 28;416(6879):455-9
references: 11919638
references: BMC Plant Biol. 2012 Apr 20;12:52
references: 22520048
references: Acta Crystallogr D Biol Crystallogr. 1998 Sep 1;54(Pt 5):905-21
references: 9757107
references: Methods Enzymol. 1997;276:307-26
references: 27754618
references: Nat Rev Mol Cell Biol. 2011 Mar;12(3):152-62
references: 21326199
references: Annu Rev Plant Biol. 2006;57:599-621
references: 16669775
references: Physiol Plant. 2012 May;145(1):224-34
references: 22008015
references: Arch Biochem Biophys. 2011 Dec 15;516(2):85-96
references: 22027029
references: Nat Struct Mol Biol. 2010 Jul;17(7):844-52
references: 20581825
references: Annu Rev Genet. 2004;38:709-24
references: 15568990
references: Acta Crystallogr D Biol Crystallogr. 2008 Jan;64(Pt 1):49-60
references: 18094467
references: Curr Opin Plant Biol. 2012 Jun;15(3):245-51
references: 22386092
references: Acta Crystallogr Sect F Struct Biol Cryst Commun. 2013 Jan 1;69(Pt 1):69-72
references: 23295491
references: Plant Physiol. 2012 Aug;159(4):1428-39
references: 22698923
references: J Biol Chem. 2003 Feb 21;278(8):6543-51
references: 12458220
references: Plant Physiol. 2010 Mar;152(3):1263-73
references: 20089771
references: Structure. 2012 Jun 6;20(6):1040-50
references: 22578544
references: Nucleic Acids Res. 2010 Jul;38(Web Server issue):W555-62
references: 20478824
references: Nat Struct Mol Biol. 2012 Jan 15;19(2):152-7
references: 22245966
references: Plant Cell. 2007 Mar;19(3):1039-47
references: 17351117
references: EMBO J. 2001 Feb 15;20(4):713-22
references: 11179216
references: Plant Cell. 2010 Mar;22(3):541-63
references: 20354197
references: Nature. 2008 Jun 12;453(7197):885-90
references: 18496527
references: J Biol Chem. 2012 Oct 26;287(44):37564-9
references: 22961982