The Cold Signaling Attenuator HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE1 Activates FLOWERING LOCUS C Transcription via Chromatin Remodeling under Short-Term Cold Stress in Arabidopsis

• Published in: The Plant cell 2013-11, Vol.25 (11), p.4378-4390
• Main Authors: Jung, Jae-Hoon, Park, Ju-Hyung, Lee, Sangmin, To, Taiko Kim, Kim, Jong-Myong, Seki, Motoaki, Park, Chung-Mo
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Antibodies; Arabidopsis; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Carrier Proteins - genetics; Carrier Proteins - metabolism; Cell Nucleus - genetics; Chromatin; Chromatin - metabolism; Chromatin Assembly and Disassembly - genetics; cold; cold stress; Cold Temperature; Flowering; Flowers - genetics; Gene expression regulation; Gene Expression Regulation, Plant; Genes; histone deacetylase; Histone Deacetylases - genetics; Histone Deacetylases - metabolism; Intracellular Signaling Peptides and Proteins - genetics; Intracellular Signaling Peptides and Proteins - metabolism; loci; MADS Domain Proteins - genetics; MADS Domain Proteins - metabolism; Molecular Sequence Data; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Plant cells; Plants; Plants, Genetically Modified; Proteins; Stress, Physiological; transcription (genetics); Transcription, Genetic; Transcriptional regulatory elements; Transgenic plants
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.113.118364

Exposure to short-term cold stress delays flowering by activating the floral repressor FLOWERING LOCUS C (FLC) in Arabidopsis thaliana. The cold signaling attenuator HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE1 (HOS1) negatively regulates cold responses. Notably, HOS1-deficient mutants exhibit early flowering, and FLC expression is suppressed in the mutants. However, it remains unknown how HOS1 regulates FLC expression. Here, we show that HOS1 induces FLC expression by antagonizing the actions of FVE and its interacting partner histone deacetylase 6 (HDA6) under short-term cold stress. HOS1 binds to FLC chromatin in an FVE-dependent manner, and FVE is essential for the HOS1-mediated activation of FLC transcription. HOS1 also interacts with HDA6 and inhibits the binding of HDA6 to FLC chromatin. Intermittent cold treatments induce FLC expression by activating HOS1, which attenuates the activity of HDA6 in silencing FLC chromatin, and the effects of intermittent cold are diminished in hos1 and fve mutants. These observations indicate that HOS1 acts as a chromatin remodeling factor for FLC regulation under short-term cold stress.