Amino acid sequence alignment of selected Homarus americanus receptors for peptide families in which multiple full-length receptors were identified.

(A) Alignment of allatostatin-C receptor (AST-CR) I and II. (B) Alignment of pigment dispersing hormone receptor (PDHR) I and II. In each panel, “*” located beneath each line of the alignment indicates residues that are identical in the two sequences, while “:” and “.” indicate highly conservative and conservative substituted (similar) amino acids, respectively, shared between the two proteins. In this figure, the rhodopsin-like G protein-coupled receptor (GPCR) seven transmembrane domains identified by InterPro in each of the two AST-CRs are highlighted in black, while the GPCR family 2 extracellular hormone receptor domain and the GPCR family 2-like seven transmembrane region identified by InterPro in the each PDHR are highlighted in red and dark blue, respectively.