One of the families that exemplified the trend found in virusmetazoa Pfam families is the PAAD/DAPIN/Pyrin family (PAAD_DAPIN, PF02758). This domain family is a diverse family (26% average sequence identity) that includes 34 cellular species and 5 dsDNA viruses that belong to the Poxviridae. The PAAD domain is at the N-terminal regions of proteins. This domain occurs in several multicellular organisms, in the context of inflammation, signaling and apoptosis ( Figure 4) .