title: Direct Repression of Evening Genes by CIRCADIAN CLOCK-ASSOCIATED1 in the Arabidopsis Circadian Clock.
abstract: The circadian clock is a biological timekeeping system that provides organisms with the ability to adapt to day-night cycles. Timing of the expression of four members of the Arabidopsis thaliana PSEUDO-RESPONSE REGULATOR(PRR) family is crucial for proper clock function, and transcriptional control of PRRs remains incompletely defined. Here, we demonstrate that direct regulation of PRR5 by CIRCADIAN CLOCK-ASSOCIATED1 (CCA1) determines the repression state of PRR5 in the morning. Chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) analyses indicated that CCA1 associates with three separate regions upstream of PRR5 CCA1 and its homolog LATE ELONGATED HYPOCOTYL (LHY) suppressed PRR5 promoter activity in a transient assay. The regions bound by CCA1 in the PRR5 promoter gave rhythmic patterns with troughs in the morning, when CCA1 and LHY are at high levels. Furthermore,ChIP-seq revealed that CCA1 associates with at least 449 loci with 863 adjacent genes. Importantly, this gene set contains genes that are repressed but upregulated incca1 lhy double mutants in the morning. This study shows that direct binding by CCA1 in the morning provides strong repression of PRR5, and repression by CCA1 also temporally regulates an evening-expressed gene set that includes PRR5.
authors.affiliation: School of Agriculture, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Kamioka
authors.affiliation: Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Saori
authors.initials: S
authors.lastname: Takao
authors.affiliation: Exploratory Research for Advanced Technology (ERATO) Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan College of Bioscience and Biotechnology, Chub University, Kasugai 487-8501, Japan Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Takamasa
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Kyomi
authors.initials: K
authors.lastname: Taki
authors.affiliation: Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan Exploratory Research for Advanced Technology (ERATO) Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Higashiyama
authors.affiliation: Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Toshinori
authors.identifier: http://orcid.org/0000-0001-7621-1259
authors.initials: T
authors.lastname: Kinoshita
authors.affiliation: Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan nnakamichi@itbm.nagoya-u.ac.jp.
authors.forename: Norihito
authors.initials: N
authors.lastname: Nakamichi
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D057906:Circadian Clocks / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D018546:Hypocotyl / Q000235:genetics / Q000502:physiology; D009154:Mutation; D059372:Nucleotide Motifs; D011401:Promoter Regions, Genetic / Q000235:genetics; D017423:Sequence Analysis, RNA; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C114425:CCA1 protein, Arabidopsis; C523307:PRR5 protein, Arabidopsis; D014157:Transcription Factors