Izuddin Abu and Rayan Alansari

1. Expression data from Arabidopsis thaliana (Ler) rosette leaves treated with paraquat (methyl viologen) Izuddin Abu and Rayan Alansari Leaves harvested 1, 2& 4 h after spraying either with 20 µM paraquatin 0.1% Tween or with Tween alone for RNA extraction and hybridization on Affymetrix ATH1 microarrays. Plants grown on soil for 3 weeks under continuous light at 90 mmol. m-2 . s-1. cDNA were prepared from total RNAs from two separate biological experiments and subsequent synthesis of biotin-labeled complementary RNA recommended by Affymetrix. Microarray is used to detail Arabidopsis gene expression in response to paraquat which may enhance generation of superoxide and hydrogen peroxide inside plastids. Within a few hours after paraquat treatment changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by another reactive oxygen species, singlet oxygen.