title: Dissection of Arabidopsis NCED9 promoter regulatory regions reveals a role for ABA synthesized in embryos in the regulation of GA-dependent seed germination.
abstract: Nine-cis-epoxycarotenoid dioxygenase (NCED) catalyzes the key step of abscisic acid (ABA) biosynthesis. There are five genes encoding NCED in Arabidopsis, which differentially regulate ABA biosynthesis in a spatiotemporal manner in response to endogenous and environmental stimuli. Previous studies have shown that NCED9 is expressed in testa and embryos during seed development. In the present study, we have identified promoter regions required for the expression of NCED9 in testa and embryos, respectively. Electrophoretic mobility shift assays (EMSA) and yeast one-hybrid (Y1H) assays showed that several homeodomain-leucine zipper (HD-Zip) proteins, namely ATHBs, bound to the sequence required for expression of NCED9 in testa, suggesting that they redundantly regulate NCED9 expression. By expressing the NCED9 gene under the control of a deleted NCED9 promoter in an nced9 mutant expression was limited to embryos. Transformants were complemented for the paclobutrazol resistant germination phenotype of the mutant, suggesting that the ABA synthesis mediated by NCED9 in embryos plays an important role in the regulation of gibberellin (GA)-dependent seed germination.
authors.affiliation: RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan; Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France. Electronic address: mitsunori.seo@riken.jp.
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Seo
authors.affiliation: RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kanno
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Frey
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.
authors.forename: Helen M
authors.initials: HM
authors.lastname: North
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France. Electronic address: Annie.Marion-Poll@versailles.inra.fr.
authors.forename: Annie
authors.initials: A
authors.lastname: Marion-Poll
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D017360:Arabidopsis / Q000187:drug effects / Q000196:embryology* / Q000235:genetics*; D001483:Base Sequence; D049308:Dioxygenases / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005816:Genetic Complementation Test; D018525:Germination / Q000187:drug effects / Q000235:genetics; D005875:Gibberellins / Q000494:pharmacology; D009154:Mutation / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding / Q000187:drug effects; D012639:Seeds / Q000187:drug effects / Q000235:genetics*; D017384:Sequence Deletion / Q000235:genetics; D019076:Transgenes
chemical_list: D005875:Gibberellins; D010940:Plant Proteins; D000040:Abscisic Acid; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase
keywords: ATHB; Abscisic acid (ABA); Arabidopsis; Nine-cis-epoxycarotenoid dioxygenase (NCED); Promoter; Seed germination