title: Flowering of Arabidopsis cop1 mutants in darkness.
abstract: To elucidate the role of the COP1 gene in flowering, we analyzed flowering of cop1 mutant lines in darkness. When grown in the presence of 1% (w/v) sucrose, the cop1-6 mutant flowered in darkness, but cop1-1 and cop1-4 did not. However, cop1-1 and cop1-4 flowered in darkness when grown in the presence of 5% (w/v) sucrose. Therefore, the COP1 gene represses not only photomorphogenesis in seedlings but also flowering in darkness. Comparison of mRNAs levels of floral identity genes in cop1-6 and wild-type plants grown in darkness revealed increased mRNA levels of genes that act downstream of CO and reduced FLC mRNA level in cop1-6. Double mutants of cop1-6 and each of the late-flowering mutations cry2-1, gi-2, co-1, and ld-1 flowered in darkness. All of the double mutants except cry2-1 cop1-6 flowered later than cop1-6, demonstrating that cop1-6 is epistatic to cry2-1 for early flowering. The ld-1 cop1-6 double mutant flowered much earlier than the ld-1 mutant. The delay in flowering in the double mutants was not strongly influenced by the light conditions, whereas that of the gi-2 cop1-6 double mutant was reduced in darkness.
authors.affiliation: Division of Biological Sciences, Graduate School of Science, Hokkaido University, N10 W8, Sapporo, 060-0810 Japan.
authors.forename: Mayu
authors.initials: M
authors.lastname: Nakagawa
authors.forename: Yoshibumi
authors.initials: Y
authors.lastname: Komeda
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D003470:Culture Media; D003624:Darkness; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D008027:Light; D019697:Onions / Q000166:cytology / Q000235:genetics; D030821:Plants, Genetically Modified; D013395:Sucrose / Q000494:pharmacology; D013997:Time Factors; D044767:Ubiquitin-Protein Ligases
chemical_list: D029681:Arabidopsis Proteins; D003470:Culture Media; D013395:Sucrose; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases