Comparison of the effects of pyrokinins and related peptides identified from arthropods on pupariation behaviour in flesh fly (Sarcophaga bullata) larvae (Diptera: Sarcophagidae).
Peptides from the pyrokinin/PBAN family and some structurally related compounds identified in various arthropods were tested for acceleration of puparial contraction in flesh fly larvae. Modifications of behavioural patterns of pupariation were further studied for the active compounds using a behavioural analysis based on the recording of changes in tension of the cuticle. Nine peptides belonging to the pyrokinin/PBAN family (Lem-PK, Pea-PK-5, Lom-PK II, Hez-PBAN, Bom-DH-I), identified in five different insect species, two pyrokinin peptides derived from the genome of Drosophila melanogaster (capa-3, and hugin), and two pyrokinins identified from the white shrimp Penaeus vannamei were very active in the pupariation assay, with threshold doses within the range of 0.1-5.0 pmol larva(-1). High activity was also detected for a related peptide ETH1 from Drosophila. All of these peptides share a C-terminal PRLamide, which is essential and sufficient for the activity. Interestingly, two other structurally related peptides from Drosophila--ETH2 and capa-1--which feature conservative changes (Ile and Val, respectively) at the C-terminal Leu position, were inactive within a physiological range of concentrations. It is clear that the receptor mediating the acceleration of puparial contraction behaviour is sensitive to the introduction of greater steric bulk at the C-terminal Leu position. The peptides that accelerated pupariation showed very similar patterns of muscular and cuticular activity.
Zdárek
Jan
J
Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic. zdarek@uochb.cas.cz
Verleyen
Peter
P
Mares
Michael
M
Dolecková
Lucie
L
Nachman
Ronald J
RJ
D000818:Animals; D001181:Arthropods / Q000737:chemistry; D001685:Biological Factors / Q000032:analysis / Q000502:physiology; D004175:Diptera / Q000187:drug effects / Q000254:growth & development*; D007301:Insect Hormones / Q000502:physiology*; D019476:Insect Proteins / Q000032:analysis / Q000502:physiology*; D008675:Metamorphosis, Biological / Q000187:drug effects / Q000502:physiology*; D009479:Neuropeptides / Q000145:classification / Q000502:physiology*; D011679:Pupa / Q000187:drug effects / Q000254:growth & development
D001685:Biological Factors; D007301:Insect Hormones; D019476:Insect Proteins; D009479:Neuropeptides; C079709:pheromone biosynthesis activating neuropeptide, Helicoverpa zea; C079229:pyrokinin