Table 1.
Core apoptosis domains in several completed animal genomes
| Classification | Species | NB-ARC domain | Bcl-2 (multi-motif) | Caspase | CARD domain | Death domain (DD) | Death effector domain (DED) |
| Vertebrata | H. sapiens (human) | 1 (1) | 17 (12) | 11 (11) | 23 (22) | 31 (29) | 8 (8) |
| M. musculus (mouse) | 1 (1) | 15 (11) | 9 (9) | 23 (21) | 28 (25) | 6 (6) | |
| C. familiaris (dog) | 1 (1) | 14 (10) | 14 (14) | 20 (19) | 37 (33) | 5 (5) | |
| G. gallus (chicken) | 1 (1) | 13 (7) | 13 (13) | 13 (12) | 30 (24) | 6 (6) | |
| X. tropicalis (western clawed frog) | 1 (1) | 14 (11) | 13 (13) | 28 (28) | 31 (28) | 5 (5) | |
| B. rerio (zebrafish) | 1 (1) | 16 (13) | 21 (21) | 30 (28) | 35 (33) | 5 (5) | |
| F. rubripes (Japanese pufferfish) | 1 (1) | 15 (12) | 13 (13) | 15 (14) | 32 (28) | 6 (6) | |
| T. nigroviridis (green pufferfish) | 1 (1) | 13 (11) | 14 (14) | 14 (12) | 33 (30) | 5 (4) | |
| Cephalochordata | B. floridae (amphioxus) | 16 (16) | 7 (7) | 53 (53) | 84 (84) | 139 (136) | 57 (57) |
| Urochordata | C. intestinalis (sea squirt) | 0* | 1 (1) | 11 (11) | 2 (2) | 5 (4) | 2 (2) |
| Echinodermata | S. purpuratus (purple sea urchin) | 5 (5) | 8 (8) | 42 (42) | 12 (10) | 87 (82) | 3 (3) |
| Ecdysozoa | D. melanogaster (fruit fly) | 1 (1) | 2 (2) | 7 (7) | 1 (0) | 5 (5) | 0 |
| C. elegans | 1 (1) | 1 (1) | 5 (5) | 1 (1) | 2 (2) | 0 | |
| Cnidaria | N. vectensis (starlet sea anemone) | 4 (4) | 11 (11) | 10 (10) | 8 (8) | 5 (5) | 9 (9) |
The total numbers of full-length protein sequence matches to the corresponding human sequences are shown; the number of hits confirmed by Pfam and CD-Search under default thresholds displayed in parentheses (see Materials and methods). We have to stress that the number of proteins in all recently sequenced genomes is approximate because of the diversity of domain sequences and experimental verification of only limited numbers of gene predictions. Therefore, exact counts of the members of these families strongly depend on significance thresholds for gene predictions and specific homology-recognition tools used in the analysis. *We were unable to detect an NB-ARC domain in C. intestinalis, probably due to sequence/assembly problems in this genome.