title: INDUCER OF CBF EXPRESSION 1 integrates cold signals into FLOWERING LOCUS C-mediated flowering pathways in Arabidopsis.
abstract: Plants constantly monitor changes in photoperiod and temperature throughout the year to synchronize flowering with optimal environmental conditions. In the temperate zones, both photoperiod and temperature fluctuate in a somewhat predictable manner through the seasons, although a transient shift to low temperature is also encountered during changing seasons, such as early spring. Although low temperatures are known to delay flowering by inducing the floral repressor FLOWERING LOCUS C (FLC), it is not fully understood how temperature signals are coordinated with photoperiodic signals in the timing of seasonal flowering. Here, we show that the cold signaling activator INDUCER OF CBF EXPRESSION 1 (ICE1), FLC and the floral promoter SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) constitute an elaborate signaling network that integrates cold signals into flowering pathways. The cold-activated ICE1 directly induces the gene encoding FLC, which represses SOC1 expression, resulting in delayed flowering. In contrast, under floral promotive conditions, SOC1 inhibits the binding of ICE1 to the promoters of the FLC gene, inducing flowering with a reduction of freezing tolerance. These observations indicate that the ICE1-FLC-SOC1 signaling network contributes to the fine-tuning of flowering during changing seasons.
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, 151-742, Korea.
authors.forename: Jae-Hyung
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, 151-742, Korea.|Sainsbury Laboratory, Cambridge University, 47 Bateman Street, Cambridge CB2 1LR, UK.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Jung
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, 151-742, Korea.|PGBI, Seoul National University, Seoul, 151-742, Korea.
authors.forename: Chung-Mo
authors.initials: CM
authors.lastname: Park
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D003080:Cold Temperature; D018506:Gene Expression Regulation, Plant; D026161:MADS Domain Proteins / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C418902:At5g10140 protein, Arabidopsis; C510502:ICE1 protein, Arabidopsis; D026161:MADS Domain Proteins; D014157:Transcription Factors
keywords: Arabidopsis thaliana; FLC; ICE1; SOC1; cold acclimation; flowering time