Cockroaches pheromone biosynthesis

Abstract Pheromones are utilized by many insects in a complex chemical communication system. This review will look at the biosynthesis of sex and aggregation pheromones in the model insects, moths, flies, cockroaches, and beetles. The biosynthetic pathways involve altered pathways of normal metabolism of fatty acids and isoprenoids. Endocrine regulation of the biosynthetic pathways will also be reviewed for the model insects. A neuropeptide named pheromone biosynthesis activating neuropeptide regulates sex pheromone biosynthesis in moths. Juvenile hormone regulates pheromone production in the beetles and cockroaches, while 20-hydroxyecdysone regulates pheromone production in the flies. 

Moths, beetles, flies, and cockroaches have received the most attention regarding pheromone biosynthesis because their members contain prominent pest species and in addition are typically easy to rear in the laboratory. However several other insects have been investigated regarding pheromone biosynthesis, most notably the bees and butterflies. 

It was determined that the minimal peptide sequence required to stimulate pheromone biosynthesis was the C-terminal 5 amino acids, FXPRLamide, and that the carboxy terminus needs to be amidated [148,149]. This sequence was also established as the minimal sequence required for myotropic activity in cockroaches [ 150] and induction of embryonic diapause in B. mori [ 151 ]. Crossreactivity of peptides containing the FXPRLamide motif was also established for myotropic, diapause induction, and pheromone biosynthesis [152-154]. Therefore, the common C-terminal FXPRLamide defines this family of peptides. A partial listing of peptides identified to date is shown in Table 1. 

Schal, C., Fan, Y. and Blomquist, G. J. (2003). Regulation of pheromone biosynthesis, transport, and emission in cockroaches. In Insect Pheromones Biochemistry and Molecular Biology, eds. G. J. Blomquist and R. Vogt, pp. 283-322. New York Academic Press. 

Regulation of pheromone biosynthesis, transport, and emission in cockroaches... 

When the full structure of the pheromone biosynthesis activating neuropeptide (PBAN) from the corn earworm Heliothis zea was recently reported (28), we noted that the sequence contained the pyrokinin C-terminal pentapeptide fragment Phe-X-Pro-Arg-Leu-NH2 (X - Ser), identical to that contained in locustamyotropin I (Figure 5) (27). Indeed [Nle, Nle ]PBAN demonstrates LPK-like contractile activity in the heterologous cockroach hindgut and oviduct assays, retaining a full 25% of LPK activity on the isolated Leucophaea oviduct (Holman, G. M. and Nachman, R. J., unpublished data.). 

Sequence homology has been noted previously (17) between the N-terminus of Hez-PBAN and insulin-like growth factor II, and the C-terminus with the insect peptide leucopyrokinin (Table II) isolated from cockroach heads. The striking similarity of the first 16 residues of the melanization and reddish colorization hormone (MRCH) of B. mori (18) and Bom-PBAN has led to the suggestion by Kitamura ti 1. (17) that they are identical (Table II), thus implying a dual role for this hormone in the larvae (melanization and reddish colorization) and adult moth (pheromone biosynthesis). 

Fig. (7) shows pheromone biosynthesis regulated by JH in production of a number of cockroach and beetle species [80-84]. 20-... 

Biosynthesis and endocrine control of the production of the German cockroach sex pheromone, 3,1 l-dimethylnonacosan-2-one. Proceedings of the National Academy of Sciences, USA 89 6050-6054. 

Gu, X., Quilici, D., Juarez, P, Blomquist, G. J. and Schal, C. (1995). Biosynthesis of hydrocarbons and contact sex pheromone and their transport by lipophorin in females of the German cockroach (Blattella germanica). Journal of Insect Physiology 41 257-267. 

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