Fig. 6. Comparison of deduced partial amino acid sequences of the putative trout VPAC₁ (A) and VPAC₂ (B) receptors with those of selected vertebrates. Conserved amino acids (100% identity) among taxa are highlighted. Sequences were aligned using CLUSTAL W and the alignment was prepared from DNAMAN. The putative trans-membrane domains (TMDs) are denoted by horizonatal arrows and were deduced by visual inspection of published reports and by hydrophobocity analysis. The G_sa-protein coupling motif (basic-L/A L/A/V/S-basic) is shown by a plus. The RLA K/R motif is common to members of the G-protein-coupled receptor family. The PD I/V motif common to vasoactive intestinal polypeptide (VIP)-binding receptors is shown by an asterisk. Finally, the conserved cysteine preceding the IIRIL motif, common only to VPAC₁ receptors, is shown by a dagger. Sequences were edited to include only the region spanning the primer sites used to obtain the trout partial cDNA clones.