Figure 2

Phylogenetic analysis of the enzymes involved in the prostaglandin pathway. (a–c) Bayesian mid-point routed phylogenetic trees of COX-1 (a), PTGE Synthase (b), PTGD Synthase (c) proteins from pennate and centric diatoms. Sequences from other organisms are also included as outgroup. Sequences used for phylogenetic analyses are listed in Supplementary Table S3. The trees were built on scale in the branch length (scale bars reported). Sequences are identified by the species name and annotation (where applicable), followed by their MMETSP ID deprived of the taxon ID for simplicity or GenBank accession number. Posterior probability (PP) values are represented with symbols at the nodes: star represents PP above or equal to 0.95; square PP between 0.75 and 0.95; triangle below 0.75. Branch coloring refers to PP, color code is reported in figure. (a) COX and COX-like proteins (2 000 000 generations, split frequency standard deviation (s.d.)=0.002); (b) PTGE synthase proteins (5 000 000 generations, split frequency s.d.=0.01 (c) PTGD synthase (10 000 000 generations, split frequency s.d.=0.04). For simplicity, large sequence clusters were condensed and identified by numbers and the nine main clades were identified by letters highlighted with vertical bars on the right side of the picture. Numbers do not correspond to a rank (see details in Supplementary Information and Supplementary Figure S7).