HvNAC gene expression patterns. Heatmaps showing the gene expression patterns across different tissues of the barley plant and following 3 or 5 hours of treatment with the plant hormones abscisic acid (ABA) or methyl jasmonate (MeJA) for 46 HvNAC genes and Rubisco (small subunit) as control gene. Relative gene expression levels at the log2 scale are indicated by a color scale, where red indicates high and green low expression. The color bars in the lower corners show the range of gene expression differences in the two types of experiments. White color in the hormone experiment indicates excluded HvNAC genes with expression data of poor quality (aberrant dissociation curves at low expression levels). The gene expression levels were determined by quantitative real-time PCR as described in the material and methods section. In brief, the presented expression data are based on three (tissues) or two (hormone treatments) biological replicates, each with three technical replicate PCR runs, followed by normalization to the expression of the 18 S ribosomal RNA gene. Prior to construction of the heatmap for the tissue experiment, the relative expression values for each gene were re-scaled to have mean equal to zero. Asterisks in the hormone experiments indicate significant differences at the 0.05 level between treatment and control (p-values adjusted for multiple comparisons according to default settings in the Limma software).