Expression changes for genes in significantly overrepresented Biological Process GO categories in leaves. To identify BP gene ontology terms overrepresented in our data sets, we combined all DEGs from leaves. Overrepresented gene ontology terms were identified using the Ontologizer 2.0 software  with parent–child-union analysis and Westfall-Young-Single-Step multiple testing correction, with a resampling of 1000 replicates. Since many of the DEGs were associated with multiple GO terms, any significant (P < 0.05) GO terms with completely overlapping DEGs were mapped to the larger (more DEGs) GO term. This data is shown in Table 2. Gene expression was plotted across time points (1 L, 1 hour leaves, 6 L, 6 hour leaves) and iron conditions (S, sufficient, D, deficient) to visualize changes. For each differentially expressed gene, both replicates are plotted with a line joining expression under deficient and sufficient conditions. The line is placed at the average of the two replicates within a condition. DEG significance within a time point is indicated by the intensity of the line.