Figure 3.

Differentially Expressed Genes of C. reinhardtii, C. paradoxa, and P. purpureum

Visualization of all differentially expressed genes of C. reinhardtii, C. paradoxa, and P. purpureum, colored according to the logarithmic fold change relative to the average expression across all conditions, mean centered and color coded in log2 space. For C. reinhardtii and C. paradoxa, the fold change's significance of all visualized transcripts is at least 0.001. For P. purpureum, the significance cutoff was lowered to 0.05, because the original cutoff revealed only 90 differentially expressed genes. C. reinhardtii shows distinct sets of genes, each tailored toward one of the tested light conditions. C. paradoxa and P. purpureum, on the other hand, do not show such an adaptation to altering light conditions, especially not to high-light (p = 0.001). C. paradoxa does not change much of its gene expression between daylight and high-light conditions, showing its lack of adaptation. Although P. purpureum expresses a set of genes only during high-light conditions, their differential expression was only detectable by lowering the significance cutoff. Even if all differentially expressed genes of P. purpureum are considered, its transcriptional changes during high-light remain minor.