title: CONSTITUTIVE PHOTOMORPHOGENIC 10 (COP10) Contributes to Floral Repression under Non-Inductive Short Days in Arabidopsis.
abstract: In Arabidopsis, CONSTITUTIVE PHOTOMORPHOGENIC/DE-ETIOLATED/FUSCA (COP/DET/FUS) genes act in repression of photomorphogenesis in darkness, and recent reports revealed that some of these genes, such as COP1 and DET1, also have important roles in controlling flowering time and circadian rhythm. The COP/DET/FUS protein COP10 interacts with DET1 and DNA DAMAGE-BINDING PROTEIN 1 (DDB1) to form a CDD complex and represses photomorphogenesis in darkness. The cop10-4 mutants flower normally in inductive long days (LD) but early in non-inductive short days (SD) compared with wild type (WT); however, the role of COP10 remains unknown. Here, we investigate the role of COP10 in SD-dependent floral repression. Reverse transcription-quantitative PCR revealed that in SD, expression of the LD-dependent floral inducers GI, FKF1, and FT significantly increased in cop10-4 mutants, compared with WT. This suggests that COP10 mainly regulates FT expression in a CO-independent manner. We also show that COP10 interacts with GI in vitro and in vivo, suggesting that COP10 could also affect GI function at the posttranslational level. Moreover, FLC expression was repressed drastically in cop10-4 mutants and COP10 interacts with MULTICOPY SUPPRESSOR OF IRA1 4 (MSI4)/FVE (MSI4/FVE), which epigenetically inhibits FLC expression. These data suggest that COP10 contributes to delaying flowering in the photoperiod and autonomous pathways by downregulating FT expression under SD.
authors.affiliation: Iriti Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea. mykang@snu.ac.kr.
authors.forename: Min-Young
authors.initials: MY
authors.lastname: Kang
authors.affiliation: Iriti Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea. kkoma1023@hanmail.net.
authors.forename: Hye-Young
authors.initials: HY
authors.lastname: Kwon
authors.affiliation: Iriti Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea. yunieie@snu.ac.kr.
authors.forename: Na-Yun
authors.initials: NY
authors.lastname: Kim
authors.affiliation: Iriti Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea. sakuraba0425@gmail.com.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Sakuraba
authors.affiliation: Iriti Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea. ncpaek@snu.ac.kr.
authors.forename: Nam-Chon
authors.initials: NC
authors.lastname: Paek
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D004843:Epistasis, Genetic; D035264:Flowers / Q000235:genetics* / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D009154:Mutation; D010641:Phenotype; D017440:Photoperiod; D011485:Protein Binding; D040641:Quantitative Trait Loci; D015398:Signal Transduction; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics* / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C450820:COP10 protein, Arabidopsis; D044763:Ubiquitin-Conjugating Enzymes
keywords: Arabidopsis thaliana; CONSTITUTIVE PHOTOMORPHOGENIC 10 (COP10); GIGANTEA (GI); MSI4/FVE; flowering; protein-protein interaction