Transcriptome changes triggered by Hyaloperonospora parasitica arabidopsis Noco2 in WT and wrky72 mutants at 96 hpt

Functional characterization of AtWRKY72 using Arabidopsis T-DNA insertion lines showed that this gene is important for basal defense to root-knot nematode (RKN) and Hyaloperonospora parasitica arabidopsis (Hpa), but not several tested R gene-mediated defenses.To profile transcriptional reprogramming associated with AtWRKY72-dependent basal defense we used Affymetrix ATH1 GeneChips representing ~24,000 Arabidopsis genes. Three independent biological replicates were performed with Col-0, wrky72-1 and wrky72-2 plants at 96 hpt with HpaNoco2 or mock treatment. Using a false discovery rate of less than 0.05 we identified for each of these three lines genes that showed significant transcriptional changes in response to HpaNoco2 compared to the mock-treated controls. Identification of downstream targets of WRKY72 in Arabidopsis by this microarray suggests that WRKY72 uses a unique signaling pathway that involves AP2/ERF TFs independent of the ethylene signaling pathway. We intended to identify Arabidopsis genes that are regulated in WRKY72-dependent manner in response to Hyaloperonospora parasitica arabidopsis (Hpa) at 96 hpt. For this, we used Col-0 and two wrky72 mutant lines and compared the differentially expressed genes with the hypothesis ‘genes that are specifically regulated in Col-0 but not in wrky72 mutants are WRKY72-dependent genes’.