title: Reactive oxygen species, abscisic acid and ethylene interact to regulate sunflower seed germination.
abstract: Sunflower (Helianthus annuus L.) seed dormancy is regulated by reactive oxygen species (ROS) and can be alleviated by incubating dormant embryos in the presence of methylviologen (MV), a ROS-generating compound. Ethylene alleviates sunflower seed dormancy whereas abscisic acid (ABA) represses germination. The purposes of this study were to identify the molecular basis of ROS effect on seed germination and to investigate their possible relationship with hormone signalling pathways. Ethylene treatment provoked ROS generation in embryonic axis whereas ABA had no effect on their production. The beneficial effect of ethylene on germination was lowered in the presence of antioxidant compounds, and MV suppressed the inhibitory effect of ABA. MV treatment did not alter significantly ethylene nor ABA production during seed imbibition. Microarray analysis showed that MV treatment triggered differential expression of 120 probe sets (59 more abundant and 61 less abundant genes), and most of the identified transcripts were related to cell signalling components. Many transcripts less represented in MV-treated seeds were involved in ABA signalling, thus suggesting an interaction between ROS and ABA signalling pathways at the transcriptional level. Altogether, these results shed new light on the crosstalk between ROS and plant hormones in seed germination.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, UMR CNRS 7622, Paris, 75005, France.
authors.forename: Hayat
authors.initials: H
authors.lastname: El-Maarouf-Bouteau
authors.forename: Yasar
authors.initials: Y
authors.lastname: Sajjad
authors.forename: Jérémie
authors.initials: J
authors.lastname: Bazin
authors.forename: Nicolas
authors.initials: N
authors.lastname: Langlade
authors.forename: Simona M
authors.initials: SM
authors.lastname: Cristescu
authors.forename: Sandrine
authors.initials: S
authors.lastname: Balzergue
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Baudouin
authors.forename: Christophe
authors.initials: C
authors.lastname: Bailly
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D005030:Ethylenes / Q000378:metabolism* / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects; D006368:Helianthus / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D008954:Models, Biological; D020411:Oligonucleotide Array Sequence Analysis; D010269:Paraquat / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012639:Seeds / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D059467:Transcriptome / Q000187:drug effects / Q000235:genetics
chemical_list: D005030:Ethylenes; D017382:Reactive Oxygen Species; D000040:Abscisic Acid; C036216:ethylene; D010269:Paraquat
keywords: Helianthus annuus; dormancy; transcriptome