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

作者：Baruah Aiswarya; Simkova Klara; Apel Klaus^*; Laloi Christophe

来源：Plant Molecular Biology, 2009, 70(5): 547-563.

DOI：10.1007/s11103-009-9491-0

• Arabidopsis
• Oxidative stress
• Singlet oxygen
• Signaling
• flu mutant
• AAA-ATPase

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 (constitutive activators of AAA-ATPase, caa) or abrogated the (1)O(2)-dependent up-regulation of these genes as seen in the transgenic parental flu line (non-activators of AAA-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.

• 出版日期2009-7