title: A chloroplast ABC1-like kinase regulates vitamin E metabolism in Arabidopsis.
abstract: In bacteria and mitochondria, ABC1 (for Activity of bc1 complex)-like kinases regulate ubiquinone synthesis, mutations causing severe respiration defects, including neurological disorders in humans. Little is known about plant ABC1-like kinases; in Arabidopsis (Arabidopsis thaliana), five are predicted in mitochondria but, surprisingly, six are located at lipid droplets in chloroplasts. These are a known site of prenylquinone (including tocopherol [vitamin E], phylloquinone [vitamin K] and plastoquinone) metabolism and contain a large proportion of the tocopherol cyclase (VTE1) required for vitamin E synthesis and recycling. Therefore, ABC1-like kinases may be involved in the regulation of chloroplast prenylquinone metabolism. Using a nontargeted lipidomics approach, we demonstrate that plants lacking the plastoglobule ABC1-like kinase ABC1K3 are defective both for the production of plastochromanol-8 (a plastoquinone-derived lipid antioxidant) and the redox recycling of α-tocopherol, whereas tocopherol production is not affected. All of these pathways require VTE1 activity. However, in the abc1k3 mutant, VTE1 levels are strongly reduced posttranscriptionally. We provide evidence that the ABC1-like kinase ABC1K3 phosphorylates VTE1, possibly stabilizing it at plastoglobules. However, ABC1K3 may also have other targets and be involved in a wider chloroplast regulatory network.
authors: Laboratory of Plant Physiology, University of Neuchâtel, 2000 Neuchâtel, Switzerland.
authors: Jacopo
authors: J
authors: Martinis
authors: Gaétan
authors: G
authors: Glauser
authors: Sergiu
authors: S
authors: Valimareanu
authors: Felix
authors: F
authors: Kessler
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D002839:Chromans / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D019751:Intramolecular Transferases / Q000235:genetics / Q000378:metabolism; D008027:Light; D008969:Molecular Sequence Data; D009154:Mutation; D010766:Phosphorylation; D030821:Plants, Genetically Modified; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D014810:Vitamin E / Q000031:analogs & derivatives / Q000378:metabolism*; D010837:Vitamin K 1 / Q000378:metabolism; D024502:alpha-Tocopherol / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002839:Chromans; D014810:Vitamin E; C013649:plastochromanol 8; D010837:Vitamin K 1; C000604981:ABC1K3 protein, Arabidopsis; D011494:Protein Kinases; D019751:Intramolecular Transferases; C103397:tocopherol cyclase; D024502:alpha-Tocopherol
references: J Biol Chem. 2006 Apr 21;281(16):11225-34
references: 16414959
references: Trends Plant Sci. 2012 Sep;17(9):546-55
references: 22694836
references: Plant Methods. 2011 Jul 21;7(1):23
references: 21777468
references: Anal Biochem. 1984 Apr;138(1):141-3
references: 6731838
references: Plant Physiol. 2005 Feb;137(2):713-23
references: 15665245
references: J Cell Biol. 2001 Jul 23;154(2):309-16
references: 11470820
references: Science. 2003 Aug 1;301(5633):653-7
references: 12893945
references: Plant Cell Physiol. 2010 Apr;51(4):537-45
references: 20164151
references: J Bacteriol. 2000 Sep;182(18):5139-46
references: 10960098
references: Plant Cell Physiol. 2011 Feb;52(2):213-9
references: 21217125
references: Prog Lipid Res. 2005 Nov;44(6):357-429
references: 16289312
references: Nucleic Acids Res. 1991 Mar 25;19(6):1349
references: 2030957
references: Biochem J. 2009 Dec 23;425(2):389-99
references: 19843012
references: EMBO J. 1991 Aug;10(8):2023-31
references: 1648478
references: Anal Chem. 2005 Feb 1;77(3):757-63
references: 15679341
references: Curr Genet. 2009 Feb;55(1):19-43
references: 19107486
references: Plant Physiol. 2012 Mar;158(3):1172-92
references: 22274653
references: Genome Res. 1998 Oct;8(10):1038-47
references: 9799791
references: J Exp Bot. 2012 Jun;63(10):3959-73
references: 22447966
references: Planta. 1985 Feb;163(2):201-7
references: 24249339
references: Nat Protoc. 2007;2(4):953-71
references: 17446895
references: Plant J. 2008 Aug;55(4):607-18
references: 18452591
references: Biochim Biophys Acta. 2011 May;1811(5):348-60
references: 21296186
references: Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12495-500
references: 12213958
references: Plant Cell. 1994 Jan;6(1):119-33
references: 8130642
references: Eur J Biochem. 1997 May 15;246(1):103-11
references: 9210471
references: Plant Physiol Biochem. 2010 May;48(5):301-9
references: 20036132
references: Photochem Photobiol. 2008 Nov-Dec;84(6):1388-94
references: 19067960
references: Am J Hum Genet. 2008 Mar;82(3):623-30
references: 18319072
references: J Biol Chem. 2001 May 25;276(21):18161-8
references: 11279158
references: Plant Physiol. 2008 Jun;147(2):719-31
references: 18390807
references: Plant Physiol. 2006 Mar;140(3):984-97
references: 16461379
references: Mol Biol Cell. 2011 May;22(9):1421-9
references: 21372178
references: Plant Cell. 2005 Dec;17(12):3451-69
references: 16258032
references: J Cell Biol. 1963 Apr;17:208-12
references: 13986422
references: Plant Physiol. 2006 Jun;141(2):685-701
references: 16648217