red illumination w/o lincomycin

To identify putative regulatory elements enriched in the promoters of target genes of the PGE-dependent retrograde signaling pathway, we analyzed 500 bp regions of sequence upstream of genes whose expression was down-regulated by lincomycin. We treated dark-grown Arabidopsis seedlings with lincomycin, sampled them before or after a short illumination and examined the genomic response using Affymetrix ATH1 oligonucleotide microarrays. Differentially regulated genes were ranked based on descending degree of significance (p-value) and the top 50 genes affected by lincomycin in dark grown seedlings and top 50 genes affected by the antibiotic after illumination were selected for further analysis. Keywords: does response 2*2 factorial design, two variables are (1) with/without lincomycin treatment (2) with/without red illumination. There are 2 replicates for each condition.