Characterization of a receptor for insect tachykinin-like peptide agonists by functional expression in a stable Drosophila Schneider 2 cell line.
STKR is an insect G protein-coupled receptor, cloned from the stable fly Stomoxys calcitrans. It displays sequence similarity to vertebrate tachykinin [or neurokinin (NK)] receptors. Functional expression of the cloned STKR cDNA was obtained in cultured Drosophila melanogaster Schneider 2 (S2) cells. Insect tachykinin-like peptides or "insectatachykinins," such as Locusta tachykinin (Lom-TK) III, produced dose-dependent calcium responses in stably transfected S2-STKR cells. Vertebrate tachykinins (or neurokinins) did not evoke any effect at concentrations up to 10(-5) M, but an antagonist of mammalian neurokinin receptors, spantide II, inhibited the Lom-TK III-induced calcium response. Further analysis showed that the agonist-induced intracellular release of calcium ions was not affected by pretreatment of the cells with pertussis toxin. The calcium rise was blocked by the phospholipase C inhibitor U73122. In addition, Lom-TK III was shown to have a stimulatory effect on the accumulation of both inositol 1,4,5-trisphosphate and cyclic AMP. These are the same second messengers that are induced in mammalian neurokinin-dependent signaling processes.
Torfs
H
H
Laboratory for Developmental Physiology and Molecular Biology, Zoological Institute, Leuven, Belgium.
Shariatmadari
R
R
Guerrero
F
F
Parmentier
M
M
Poels
J
J
Van Poyer
W
W
Swinnen
E
E
De Loof
A
A
Akerman
K
K
Vanden Broeck
J
J
D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004331:Drosophila melanogaster / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D007231:Infant, Newborn; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D019476:Insect Proteins / Q000494:pharmacology; D008969:Molecular Sequence Data; D009117:Muscidae / Q000378:metabolism*; D010446:Peptide Fragments / Q000819:agonists*; D018010:Receptors, Invertebrate Peptide / Q000235:genetics / Q000378:metabolism*; D018039:Receptors, Tachykinin / Q000235:genetics / Q000378:metabolism*; D015320:Tachykinins / Q000819:agonists* / Q000494:pharmacology; D014162:Transfection
D019476:Insect Proteins; D010446:Peptide Fragments; D018010:Receptors, Invertebrate Peptide; D018039:Receptors, Tachykinin; C107470:STKR receptor, Stomoxys calcitrans; D015320:Tachykinins; C068632:locustatachykinin III protein, insect; D015544:Inositol 1,4,5-Trisphosphate; D000242:Cyclic AMP; D002118:Calcium