Phylogeny of the multi-motif Bcl-2 family. This phylogeny was calculated using a Bayesian approach (MrBayes) based on a MAFFT alignment of Bcl-2 domains. Posterior probability values are shown for each branch (for detailed information, see Materials and methods). Species abbreviations: BRAFL, Branchiostoma floridae (amphioxus); BRARE, Brachydanio rerio (zebrafish); CAEBR, Caenorhabditis briggsae; CAEEL, Caenorhabditis elegans; CANFA, Canis familiaris (dog); CHICK, Gallus gallus (chicken); CIOIN, Ciona intestinalis (sea squirt); DROME, Drosophila melanogaster (fruit fly); FUGRU, Fugu rubripes (Japanese pufferfish); GEOCY, Geodia cydonium (sponge); HYDAT, Hydra attenuata; LUBBA, Lubomirskia baicalensis (freshwater sponge); NEMVE, Nematostella vectensis (starlet sea anemone); STRPU, Strongylocentrotus purpuratus (purple sea urchin); SUBDO, Suberites domuncula (sponge); TETNG, Tetraodon nigroviridis (green pufferfish); and XENTR, Xenopus tropicalis (western clawed frog). For a detailed list of protein sequences see Additional data file 3. All sequences are from complete genomes except the individual sequences from C. briggsae, G. cydonium, H. attenuata, L. baicalensis, and S. domuncula.