Fig. 4. Alignment of the known leucokinin receptor protein sequences. Amino acid residue numbers are indicated at the end of each line. The predicted TM domains are underlined. TM domains were predicted using the TMHMM 2.0 prediction program. Identical residues with a threshold limit of 75% are indicated by a shaded box. Sequence alignments were performed using CLUSTAL X, and annotated using BioEdit. Key conserved residues, such as the Asp-Arg-Tyr/His (DR^Y/_H) triplet motif after TM III, Cys (C) residues in the second and third extracellular loops and potential N-glycosylation sites are in bold type and underlined.