title: Plant Aurora kinases interact with and phosphorylate transcription factors.
abstract: Aurora kinase (AUR) is a well-known mitotic serine/threonine kinase that regulates centromere formation, chromosome segregation, and cytokinesis in eukaryotes. In addition to regulating mitotic events, AUR has been shown to regulate protein dynamics during interphase in animal cells. In contrast, there has been no identification and characterization of substrates and/or interacting proteins during interphase in plants. The Arabidopsis thaliana genome encodes three AUR paralogues, AtAUR1, AtAUR2, and AtAUR3. Among them, AtAUR1 and AtAUR2 are considered to function redundantly. Here, we confirmed that both AtAUR1 and AtAUR3 are localized in the nucleus and cytoplasm during interphase, suggesting that they have functions during interphase. To identify novel interacting proteins, we used AlphaScreen to target 580 transcription factors (TFs) that are mainly functional during interphase, using recombinant A. thaliana TFs and AtAUR1 or AtAUR3. We found 133 and 32 TFs had high potential for interaction with AtAUR1 and AtAUR3, respectively. The highly AtAUR-interacting TFs were involved in various biological processes, suggesting the functions of the AtAURs during interphase. We found that AtAUR1 and AtAUR3 showed similar interaction affinity to almost all TFs. However, in some cases, the interaction affinity differed substantially between the two AtAUR homologues. These results suggest that AtAUR1 and AtAUR3 have both redundant and distinct functions through interactions with TFs. In addition, database analysis revealed that most of the highly AtAUR-interacting TFs contained a detectable phosphopeptide that was consistent with the consensus motifs for human AURs, suggesting that these TFs are substrates of the AtAURs. The AtAURs phosphorylated several highly interacting TFs in the AlphaScreen in vitro. Overall, in line with the regulation of TFs through interaction, our results indicate the possibility of phosphoregulation of several TFs by the AtAURs (280/300).
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Takagi
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Sakamoto
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan.
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Suzuki
authors.affiliation: Proteo-Science Center, Ehime University, Matsuyama, Ehime, 791-8577, Japan.
authors.forename: Keiichirou
authors.initials: K
authors.lastname: Nemoto
authors.affiliation: Graduate School of Information Sciences, Tohoku University, Sendai, Miyagi, 980-8679, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Obayashi
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hirakawa
authors.affiliation: Institute for Science and Technology, Tokyo University of Science, Noda, Chiba, 278-8510, Japan.
authors.forename: Tomoko M
authors.initials: TM
authors.lastname: Matsunaga
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, JST ERATO Higashiyama Live-Holonics Project, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kurihara
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Shimane University, Izumo, Shimane, 693-8501, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nariai
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Shimane University, Izumo, Shimane, 693-8501, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Urano
authors.affiliation: Proteo-Science Center, Ehime University, Matsuyama, Ehime, 791-8577, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Sawasaki
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan. sachi@rs.tus.ac.jp.
authors.forename: Sachihiro
authors.initials: S
authors.lastname: Matsunaga
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D007399:Interphase; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D014157:Transcription Factors; C504614:AUR1 protein, Arabidopsis; C504616:AUR3 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases
keywords: AlphaScreen; Aurora kinase; In vitro phosphorylation assay with ATPγS; Transcription factors; Wheat germ cell-free protein synthesis