Fig. 5

Identification of lipase candidates possibly implicated in lipid accumulation. The transcription profiles of putative lipases of M. neglectum were subjected to hierarchical clustering with complete linkage based on log2-FC values with distance metric defined as Euclidean distance. The resulting dendrogram is shown on the left. The dendrogram was divided into four clusters as indicated by the dotted lines. The first column of the heatmap (N_0_FPKM) indicates the binned transcript abundance value (FPKM) at the reference time point N_0, i.e., the abundance category. The category “I” represents the range of FPKM values of 1 ≤ FPKM ≤ 11 (below median expression), category “II” the range 11 ≤ FPKM ≤ 24 (between 50 and 75% percentile expression), category “III” the range 24 ≤ FPKM ≤ 58 (between 75 and 90% percentile expression), and category “IV” the range 58 ≤ FPKM ≤ 866 (between 90 and 99% percentile expression); see Fig. 3a for the corresponding box plot. The remaining columns show the transcriptional regulation at the individual harvesting time points relative to time point zero (N_0), given as color-coded boxes. Red color represents higher transcript abundance and blue lower transcript abundance compared to time point N_0. The tag “NA” (not available) is used when the absolute transcript abundance (as FPKM) at the respective time point was less than 1.0. The three stages of N availability are separated by vertical lines, where orange represents the e−N stage, brown the l−N stage, and green the r+N stage, respectively. The locus ID and the predicted domain of each lipase transcript are given on the right. As an example for transcriptional regulation of lipase candidates possibly implicated in TAG accumulation rather than TAG degradation, the PGD1 candidate of M. neglectum is highlighted in red color. Other transcripts mentioned in the text are shown in magenta