Cloning and transcriptional expression of a leucokinin-like peptide receptor from the Southern cattle tick, Boophilus microplus (Acari : Ixodidae)

Leucokinins are invertebrate neuropeptides that exhibit myotropic and diure tic activity. Only one leucokinin-like peptide receptor is known, the lymno kinin receptor from the mollusc Lymnaea stagnalis. A cDNA encoding a leucok inin-like peptide receptor was cloned from the Southern cattle tick, Boophi lus microplus, a pest of cattle world-wide. This is the first neuropeptide receptor known from the Acari and the second known in the subfamily of leuc okinin-like peptide G-protein-coupled receptors. The deduced amino acid seq uence exhibits 40% identity to the lymnokinin receptor. The receptor transc ript is present in all tick life stages as determined by semiquantitative r everse transcription polymerase chain reaction. We also propose that the se quence AAF50775.1 from the Drosophila melanogaster genome (CG10626) encodes the first identified insect leucokinin receptor.