Abstract
In higher plants, ascorbate peroxidase (APX) isoenzymes play a key role in scavenging H2O2 and are distributed in at least five distinct cell compartments. The transcript level of cytosolic APX (cAPX) increased in response to high-light and paraquat treatment, while those of other APX isoenzymes were not changed. To search the Spinach cAPX promoter region for potential binding sites of regulatory transcription factors, we constructed chimeric genes consisting of a series of deletion of the cAPX promoter 5' region and GUS gene, and generated the transgenic Arabidopsis plants. The GUS activity in these plants were assayed to analyze the induction of cAPX expression under high-light (1,600 μE/m2/s) conditions. The results showed that transgenic plants harboring constructs -1753 bp and -1325 bp chimeric genes induces the GUS activity under high-light conditions. However, the deletion of the promoter to point -860 caused the negligible GUS activity.
