title: Arabidopsis COP10 is a ubiquitin-conjugating enzyme variant that acts together with COP1 and the COP9 signalosome in repressing photomorphogenesis.
abstract: A group of evolutionarily conserved pleiotropic COP/DET/FUS proteins was initially defined by their ability to repress photomorphogenesis in Arabidopsis. It was proposed that this regulation be mediated by targeting degradation of key cellular regulators that promote photomorphogenesis. Among them, COP1 and the COP9 signalosome have been hypothesized to fulfill the roles as an ubiquitin ligase (E3) and an essential E3 modulator. Here we report that COP10 encodes a protein similar to ubiquitin-conjugating enzyme (E2) variant proteins (UEV). COP10 is part of a nuclear protein complex and capable of directly interacting with both COP1 and the COP9 signalosome. Our data indicates that COP10 defines a possible E2 activity, thus validating the working hypothesis that the pleiotropic COP/DET/FUS group of proteins defined a protein ubiquitination pathway.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: Genki
authors.initials: G
authors.lastname: Suzuki
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yanagawa
authors.forename: Shing F
authors.initials: SF
authors.lastname: Kwok
authors.forename: Minami
authors.initials: M
authors.lastname: Matsui
authors.forename: Xing-Wang
authors.initials: XW
authors.lastname: Deng
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D000075686:COP9 Signalosome Complex; D002352:Carrier Proteins / Q000378:metabolism; D008025:Ligases / Q000235:genetics / Q000378:metabolism*; D008027:Light; D008954:Models, Biological; D008969:Molecular Sequence Data; D009024:Morphogenesis; D046912:Multiprotein Complexes; D010447:Peptide Hydrolases / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D011506:Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D025801:Ubiquitin / Q000378:metabolism*; D044763:Ubiquitin-Conjugating Enzymes; D044767:Ubiquitin-Protein Ligases
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D046912:Multiprotein Complexes; D010940:Plant Proteins; D011506:Proteins; D012097:Repressor Proteins; D025801:Ubiquitin; C450820:COP10 protein, Arabidopsis; D044763:Ubiquitin-Conjugating Enzymes; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases; D010447:Peptide Hydrolases; D000075686:COP9 Signalosome Complex; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease; D008025:Ligases