title: Expression of Kip-related protein 4 gene (KRP4) in response to auxin and cytokinin during growth of Arabidopsis thaliana.
abstract: The cell cycle is regulated by cyclin-dependent kinase (CDK)- cyclin complexes as well as other regulators. We isolated Kip-related protein 4 (KRP4) cDNA that encodes 289 amino acids including six conserved domains. To investigate the expression pattern of KRP4 as well as of other cell cycle-related genes associated with plant hormones, Arabidopsis seedlings were cultured on MS medium containing auxin or cytokinin. All seedlings treated with phytohormones displayed an increased proportion of cells in S phase. A higher proportion of cells in G2 phase was observed in seedlings treated with NAA. RT-PCR confirmed that the expression of KRP4 was decreased after treatment with phytohormones, and that CDKA and D-type cyclin transcription was increased. Additionally, mitotic cyclins were up-regulated by NAA treatment. These results suggest that KRP4 as well as other cell cycle-related genes might contribute to the control of plant growth in response to exogenous hormones.
authors.affiliation: Department of Medical Biotechnology, Kangwon National University, Chuncheon 200-701, Korea.
authors.forename: Hye-Jeong
authors.initials: HJ
authors.lastname: Cho
authors.forename: Hye-Kyoung
authors.initials: HK
authors.lastname: Kwon
authors.forename: Myeong-Hyeon
authors.initials: MH
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000145:classification / Q000378:metabolism*; D050756:Cyclin-Dependent Kinase Inhibitor Proteins / Q000737:chemistry / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism; D003583:Cytokinins / Q000737:chemistry / Q000494:pharmacology*; D016195:G2 Phase; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000737:chemistry / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009280:Naphthaleneacetic Acids / Q000494:pharmacology; D010937:Plant Growth Regulators / Q000494:pharmacology*; D016196:S Phase; D036226:Seedlings / Q000254:growth & development / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D050756:Cyclin-Dependent Kinase Inhibitor Proteins; D016213:Cyclins; D003583:Cytokinins; D007210:Indoleacetic Acids; C550809:KRP4 protein, Arabidopsis; D009280:Naphthaleneacetic Acids; D010937:Plant Growth Regulators