Abstract
To investigate the involvement of reactive oxygen species (ROS) derived from chloroplasts in plant response to environmental stress, we have created the system for transient suppression of thylakoid membrane-bound ascorbate peroxidase in Arabidopsis plants. Microarray analysis using this system revealed that ROS derived from chloroplasts affect the expression of approximately 800 genes, including the genes involved in response to plant hormones and abiotic and bitic stresses. To clarify the molecular mechanism of oxidative signaling derived from chloroplasts, we isolated and characterized paraquat-induced photooxidative stress sensitive and insensitive mutants (pss and psi, respectively) from knockout lines, which are disrupted genes responsive to ROS derived from chloroplasts. Among 109 lines, three psi (psi1~ 3) and one pss (pss1) mutants were isolated. The transcript levels of PSS1 and PSIs were suppressed at early-stage after treatment with paraquat, but were induced at late-stage.
