SOD activity and phosphorylation of histone H2AX as responses to oxidative stress caused by alterations of PP2A functioning in Arabidopsis

Abstract

From the SOD activity it is seen that the Fe-SOD activity showed the most sensitivity to induced oxidative stress denoting higher ROS. This emphasizes the phototoxic effects of ROS. The increased sensitivity in the fass-5 B regulatory subunit mutant shows that the regulation of PP2A plays a role in the mediation of SOD activity in response to oxidative stress. The DNA damage as a result of oxidative stress is higher in the homozygous recessive fass-5 mutant but for the heterozygous fass-5 genotype we did not detect marked changes in histone H2A phosphorylation . There seems to be a little positive effect.