Arabidopsis mutants reveal multiple singlet oxygen signaling pathways involved in stress response and development

• Published in: Plant molecular biology 2009-07, Vol.70 (5), p.547-563
• Main Authors: Baruah, Aiswarya, Šimková, Klára, Apel, Klaus, Laloi, Christophe
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological - genetics; Adaptation, Physiological - physiology; Adenosine Triphosphatases - genetics; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Biochemistry; Biochemistry, Molecular Biology; Biomedical and Life Sciences; Gene expression; Gene Expression Regulation, Plant - drug effects; Genomics; Hydrogen peroxide; Hydrogen Peroxide - pharmacology; Life Sciences; Luciferases - genetics; Luciferases - metabolism; Molecular biology; Mutants; Mutation; Oxidants - pharmacology; Plant biology; Plant breeding; Plant Pathology; Plant Sciences; Plants, Genetically Modified; Promoter Regions, Genetic - genetics; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Reverse Transcriptase Polymerase Chain Reaction; Rose Bengal - pharmacology; Signal Transduction - genetics; Signal Transduction - physiology; Singlet Oxygen - metabolism; Vegetal Biology
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/s11103-009-9491-0

Shortly after the release of singlet oxygen ( 1 O 2 ) in chloroplasts drastic changes in nuclear gene expression occur in the conditional flu mutant of Arabidopsis that reveal a rapid transfer of signals from the plastid to the nucleus. Factors involved in this retrograde signaling were identified by mutagenizing a transgenic flu line expressing a 1 O 2 -responsive reporter gene. The reporter gene consisted of the luciferase open reading frame and the promoter of an AAA-ATPase gene (At3g28580) that was selectively activated by 1 O 2 but not by superoxide or hydrogen peroxide. A total of eight second-site mutants were identified that either constitutively activate the reporter gene and the endogenous AAA-ATPase irrespectively of whether 1 O 2 was generated or not ( c onstitutive a ctivators of A AA-ATPase, caa ) or abrogated the 1 O 2 -dependent up-regulation of these genes as seen in the transgenic parental flu line ( n on- a ctivators of A AA-ATPase, naa ). The characterization of the mutants strongly suggests that 1 O 2 -signaling does not operate as an isolated linear pathway but rather forms an integral part of a signaling network that is modified by other signaling routes and impacts not only stress responses of plants but also their development.