Fig. 1

Domain organization of (a) the p53/p63/p73 protein family comprising the transactivation domain (TAD), DNA binding domain (DNA BD), oligomerisation domain (OD) and the sterile alpha-motif (SAM) domain. b the MDM protein family containing the p53/p63/p73-binding domain (p53/p63/p73BD), the Acidic domain, a zinc binding domain (Zinc BD) and a RING domain. c Species tree displaying the existence of p53/p63/p73 TAD (in red) and MDM p53/p63/p73BD (in blue) along with the presence of the other domains in the respective protein. Grey branches in the tree illustrate that p53/p63/p73BD and TAD is not present. The domains displayed in white indicate that the domains are present in a few organisms in that specific lineage, but in the majority of the examined species the domain could not be found. The SAM domain was lost in p53 after the whole genome duplication, denoted 1R in the tree, but is retained in vertebrate p63 and p73. This variability is illustrated with absence of lines connecting the OD and SAM domain. The second whole genome duplication is denoted 2R