Comparison of amino acid sequences of vasopressin family hormone precursors in vertebrates. The alignment was generated by ClustalX. Amino acid residues conserved in all vertebrates are marked with an asterisk. B. floridae, Branchiostoma floridae; X. tropicalis, Xenopus tropicalis; and T. scyllium, Triakis scyllium. VP, vasopressin and VT, vasotocin. Accession numbers of sequences used in the alignment: NP_000481.2 (human VP), BAA24026.1 (lungfish VT), O42499 (fugu VT), BAD27476.1 (T. scyllium VT) and BAA06669.1 (lamprey VT). Sequences for Xenopus tropicalis and coelacanth were generated in a previous study  while sequences for elephant shark (eshark) and amphioxus (B. floridae) were generated in this study.