Fig. 6
Analysis of gene expression in eight O. longistaminata tissues. a A principal component analysis using scaled and centered RPKM data from the eight indicated tissues was performed. For each tissue, the scores from the first two principal components (PC) were plotted along with the percentage of the explained variation. Symbols indicate non-rhizomatous and rhizomatous tissues, respectively. b A heatmap representation of gene expression in the eight indicated tissues is shown. Each row represents one cluster of genes and the average expression within each cluster is shown. Before averaging, gene expression was normalized by transforming RPKM values to the log2-fold change relative to the average gene-wise expression. Clustering was performed using the k-means method and k = 14 was chosen to minimize both, the number of clusters and the within-cluster sum-of-squares (elbow method)
