The Amino‐Acid Sequence of a Peptide (PS‐1) from Drosophila funebris: A Paragonial Peptide from Males which Reduces the Receptivity of the Female

Abstract
The substance, PS-1, produced in the paragonial gland of adult male Drosophila funebris influences the mating behavior of virgin female flies after injection. The substance was isolated and characterized as a 27-residue peptide. The complete amino acid sequence was determined by manual sequence analysis of tryptic peptides, automated Edman degradation, and carboxypeptidase A digestion. The sequence is Asp-ValLeu-Pro-Ser-Ala-Asn-Ala-Asn-Ala-Asn-Asn-Gln-Arg-Thr-Ala-Ala-Ala-Lys-Pro-Gln-Ala-Asn-Ala-Glu-Ala-Ser-Ser. The ratio of Val: Leu in the second position of the sequence is 7:3. This is the first detailed report on an insect peptide which causes a biological response in the opposite sex following mating.