title: Arabidopsis putative MAP kinase kinase kinases Raf10 and Raf11 are positive regulators of seed dormancy and ABA response.
abstract: We isolated an Arabidopsis ABA-insensitive mutant, ais143, by activation tagging screen. T-DNA was found to be located in the coding region of a putative mitogen-activated protein (MAP) kinase kinase kinase (MAP3K) gene, Raf10, thereby abolishing its expression in the mutant. ais143 exhibited reduced seed dormancy as well as reduced ABA sensitivity. The phenotypes were complemented by the wild-type Raf10 gene, and the overexpression (OX) of Raf10 resulted in delayed seed germination and enhanced ABA sensitivity. Raf10 has high sequence identity to another MAP3K, Raf11. Parallel analysis of Raf11 knockout (KO) and OX lines showed that their phenotypes were similar to those of Raf10 KO and OX lines. An ais143 raf11 double mutant exhibited stronger phenotypes than single mutants, indicating the functional redundancy between Raf10 and Raf11. Transcript analysis revealed that the expression of many ABA-associated genes, including the key regulatory genes ABI3 and ABI5, was altered in the Raf10 and Raf11 OX lines. Recombinant Raf10 and Raf11 proteins exhibited kinase activity, which was inhibited by the MAP3K inhibitor BAY 43-9006 but not by the MAP2K inhibitor U0126. Collectively, our data indicate that Raf10 and Raf11 kinases are important regulators of seed dormancy and ABA response and that they affect the expression of ABI3, ABI5 and other ABA-regulated genes.
authors.affiliation: Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, South Korea.
authors.forename: Sun-Ji
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, South Korea.
authors.forename: Mi Hun
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, South Korea.
authors.forename: Jeong-Il
authors.initials: JI
authors.lastname: Kim
authors.affiliation: Department of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, South Korea sooykim@chonnam.ac.kr.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Kim
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018525:Germination; D020930:MAP Kinase Kinase Kinases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation; D009536:Niacinamide / Q000031:analogs & derivatives / Q000494:pharmacology; D010671:Phenylurea Compounds / Q000494:pharmacology; D057445:Plant Dormancy; D010937:Plant Growth Regulators / Q000378:metabolism*; D030821:Plants, Genetically Modified; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011994:Recombinant Proteins; D012639:Seeds / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D000077157:Sorafenib; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D010671:Phenylurea Compounds; D010937:Plant Growth Regulators; D047428:Protein Kinase Inhibitors; D011994:Recombinant Proteins; D014157:Transcription Factors; D009536:Niacinamide; D000040:Abscisic Acid; D000077157:Sorafenib; D020930:MAP Kinase Kinase Kinases; C000604920:Raf10 protein, Arabidopsis; C000604921:Raf11 protein, Arabidopsis
keywords: Abscisic acid (ABA); Arabidopsis thaliana; MAP kinase; Raf10; Raf11; Seed dormancy