Abstract
The activity of a series of synthetic tachykinin-like peptide analogs was studied by means of microscopic calcium imaging on recombinant neurokinin receptor expressing cell lines. A C-terminal pentapeptide (FTGMRa) is sufficient for activation of the stomoxytachykinin receptor (STKR) expressed in Schneider 2 cells. Replacement of amino acid residues at the position of the conserved phenylalanine (F) or arginine (R) residues by alanine (A) results in inactive peptides (when tested at 1 ¿M), whereas A-replacements at other positions do not abolish the biological activity of the resulting insectatachykinin-like analogs. Calcium imaging was also employed to compare the activity of C-terminally substituted tachykinin analogs on three different neurokinin receptors. The results indicate that the major pharmacological and evolutionary difference between tachykinin-related agonists for insect (STKR) and human (NK1 and NK2) receptors resides in the C-terminal amino acid residues (R versus M). A single C-terminal amino acid change can turn an STKR-agonist into an NK-agonist and vice versa
Original language | English |
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Pages (from-to) | 1999-2005 |
Journal | Peptides |
Volume | 23 |
Issue number | 11 |
DOIs | |
Publication status | Published - 2002 |
Keywords
- tachykinin-related peptides
- insect neuropeptides
- urechis-unicinctus
- myotropic peptides
- echiuroid worm
- identification
- vertebrate
- homology
- family
- cockroach