PUTATIVE PHOSPHOLIPID HYDROPEROXIDE GLUTATHIONE-PEROXIDASE GENE FROM ARABIDOPSIS-THALIANA INDUCED BY OXIDATIVE STRESS

An Arabidopsis cDNA encoding putative phospholipid hydroperoxide gluta thione peroxidase (PHGPX) was cloned and sequenced. The cDNA comprised 803 bp and included an open reading frame which encodes a polypeptide of 169 amino acid residues. The deduced amino acid sequence showed ab out 80 and 50% homology with plant putative PHGPXs and mammalian PHGPX s, respectively. Southern blot analysis suggested that the putative PH GPX gene was a single-copy gene. The expression profile of the putativ e PHGPX in Arabidopsis under NaCl and Al/Fe treatments, which generate oxidative stress, was analyzed. Northern blot analysis revealed that the Arabidopsis putative PHGPX mRNA levels were increased about 3 and 4.5 times after exposure to NaCl and Al/Fe, respectively. These result s suggest that the putative PHGPX gene is induced by oxidative stress in Arabidopsis.