Fig. 1.

Phylogenetic analysis of P2X receptor homologs in select animal species and unicellular relatives of animals and three basal fungi. The phylogenetic tree was constructed by the maximum likelihood approach, with the P2X receptor in D. discoideum (DdiP2X) [11] as an outgroup. Bootstrap values of more than 40 are shown at the nodes. Abbreviations for species: Ama A. macrogynus, Aqu A. queenslandica, Bdi B. dendrobatidis, Cow C. owczarzaki, Ddi D. discoideum, Dpu Daphnia pulex, Dre Danio rerio, Gga Gallus gallus, Hsa Homo sapiens, Mbr M. brevicollis, Mga Meleagris gallopavo, Mmu Mus musculus, Sma Schistosoma mansoni, Spu S. punctatus, Stpu Strongylocentrotus purpuratus, Sro Salpingoeca rosetta