Gene maps of the Picocystis salinarum and Prasinophyceae sp. CCMP 1205 chloroplast genomes. Filled boxes represent genes, with colors denoting categories as indicated in Figure 1. Genes on the outside of each map are transcribed counterclockwise; those on the inside are transcribed clockwise. The intron sequences bordering the Picocystis ycf3 exons (ycf3a and ycf3b) are spliced in trans at the RNA level. The IR and SC regions of the Picocystis genome are represented on the inner ring. The gene clusters shared by the Picocystis and Prasinophyceae sp. CCMP 1205 genomes are displayed on the ring inside the gene map of the latter genome.