title: Arabidopsis MAP3K16 and Other Salt-Inducible MAP3Ks Regulate ABA Response Redundantly.
abstract: In the Arabidopsis genome, approximately 80 MAP3Ks (mitogen-activated protein kinase kinase kinases) have been identified. However, only a few of them have been characterized, and the functions of most MAP3Ks are largely unknown. In this paper, we report the function of MAP3K16 and several other MAP3Ks, MAP3K14/15/17/18, whose expression is salt-inducible. We preparedMAP3K16overexpression (OX) lines and analyzed their phenotypes. The result showed that the transgenic plants were ABA-insensitive during seed germination and cotyledon greening stage but their root growth was ABA-hypersensitive. The OX lines were more susceptible to water-deficit condition at later growth stage in soil. AMAP3K16knockout (KO) line, on the other hand, exhibited opposite phenotypes. In similar transgenic analyses, we found thatMAP3K14/15/17/18OX and KO lines displayed similar phenotypes to those of MA3K16, suggesting the functional redundancy among them. MAP3K16 possessesin vitrokinase activity, and we carried out two-hybrid analyses to identify MAP3K16 substrates. Our results indicate that MAP3K16 interacts with MKK3 and the negative regulator of ABA response, ABR1, in yeast. Furthermore, MAP3K16 recombinant protein could phosphorylate MKK3 and ABR1, suggesting that they might be MAP3K16 substrates. Collectively, our results demonstrate that MAP3K16 and MAP3K14/15/17/18 are involved in ABA response, playing negative or positive roles depending on developmental stage and that MAP3K16 may functionviaMKK3 and ABR1.
authors.affiliation: Department of Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea.
authors.forename: Seo-Wha
authors.initials: SW
authors.lastname: Choi
authors.affiliation: Department of Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea.
authors.forename: Seul-Bee
authors.initials: SB
authors.lastname: Lee
authors.affiliation: Department of Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea.
authors.forename: Yeon-Ju
authors.initials: YJ
authors.lastname: Na
authors.affiliation: Department of Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea.
authors.forename: Sun-Geum
authors.initials: SG
authors.lastname: Jeung
authors.affiliation: Department of Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Kim
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D048371:MAP Kinase Kinase 3 / Q000378:metabolism; D020930:MAP Kinase Kinase Kinases / Q000235:genetics* / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010766:Phosphorylation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C507549:ABR1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D010940:Plant Proteins; D014157:Transcription Factors; D000040:Abscisic Acid; D020928:Mitogen-Activated Protein Kinases; C419564:salt stress-induced MAP kinase; D020930:MAP Kinase Kinase Kinases; D048371:MAP Kinase Kinase 3
keywords: Arabidopsis thaliana; MAP kinase; MAP3K16; abiotic stress; abscisic acid (ABA)