Arabidopsis mutants treated with flg22, Alternaria brassicicola, Methyl jasmonate and Pst DC3000 bacteria

Gibberellin (GA) promotes plant growth by destabilizing DELLA proteins. DELLA proteins integrate multiple hormonal and environmental stress responses. We investigated the role of GA and DELLA proteins in plant defence. We used microarrays to detail the global programme of gene expression controlled by DELLA proteins and identified distinct classes of differentially regulated genes in response to pathogens, hormones or pathogen elicitors. Five weeks old short day grown Arabidopsis leaf discs were used to treat with flg22 and samples were collected after 1 hour and 2 hour time points. For Alternaria brassicicola, five weeks old plants were drop inoculated with 4x 5µl droplets of Alternaria brassicicola spores (5x105 spores/ml) and samples were collected 3 days post inoculation. Five weeks old plants were infiltrated with Pst DC3000 (2x105cfu/ml) bacteria and samples were collected after 12 hours post infiltration. For methyl jasmonate treatments, five weeks old plants were sprayed with 10µM Methyl Jasmonate solution, covered with plastic bags and samples were collected after one hour.