Pheromone production in moths

Rafaeli A. and Gileadi C. (1997) Neuroendocrine control of pheromone production in moths. Invert. Neurosci. 3, 223-229. 

Raina A. K. (1997) Control of pheromone production in moths. In Insect Pheromone Research New Directions, eds R. T. Carde and A. K. Minks, pp. 21-30. Chapman Hall, New York. 

Raina A. K., Kempe, T. G. and Jaffe H. (1991) Pheromone biosynthesis-activating neuropeptide Regulation of pheromone production in moths. In Insect Neuropeptides Chemistry, Biology and Action, eds J. J. Menn, T. J. Kelly and E. P. Masler, pp. 100-109. American Chemical Society, Washington, DC. 

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. 

The site of pheromone production in flies and cockroaches that utilize hydrocarbons is similar to that of the moths. Oenocyte cells produce the hydrocarbon pheromone which is transported by lipophorin in the hemolymph to epidermal cells throughout the body for release from the cuticular surface in general [20,21]. 

The role of the nervous system in pheromone biosynthesis in moths is not clearly understood. Christensen and co-workers [208-211] proposed that the neurotransmitter octopamine may be involved as an intermediate messenger during the stimulation of sex pheromone production in H. virescens. These workers suggested that octopamine was involved in the regulation of pheromone production and that PBAN s role lies in the stimulation of octopamine release at nerve endings. However, contradicting results concerning octopa-mine-stimulated pheromone production were reported in the same species as well as other moth species [163,172,212-214]. 

In moths, it was discovered in Helicoverpa zea that a peptide produced in the subesophageal ganglion portion of the brain complex regulates pheromone production in female moths (19). This factor has been purified and characterized in three species, Helicoverpa zea (20), Bombyx mori (21, 22), and Lymantria dispar (23). They are all a 33- or 34-amino acid peptide (named pheromone biosynthesis activating neuropeptide, PBAN) and have in common an amidated C-terminal 5-amino acid sequence (FXPRL-amide), which is the minimum peptide fragment required for pheromon-tropic activity. In the redbanded leafroller moth, it was shown that PBAN from the brain stimulates the release of a different peptide from the bursae copulatrix that is used to stimulate pheromone production in the pheromone gland found at the posterior tip of the abdomen (24). 

Long-distance mate location that is mediated by pheromones is true communication as defined by Burghardt (1970), in that there are selective constraints on both the females production of the signal and the males response - in other words, selection favors some individuals over others in finding a mate. In a provocative argument, Williams (1992) contended that the female odor used by males for mate location is not a pheromone, because in moths there is no special machinery ... 

Collins, R. D. and Carde, R. T. (1985). Variation in and heritability of aspects of pheromone production in the pink bollworm moth, Pectinophora gossypiella (Lepidoptera Gelechiidae). Annals of the Entomological Society of America 78 229-234. 

Figure 1.1 The three major types of hormones that regulate pheromone production in insects. A Juvenile Hormone III (C16 JH), B 20-Hydroxyecdysone and C PBANs from the corn earworm, Helicoverpa zea (Raina et al., 1989), the silkworm moth Bombyx mori (Kitamura et al., 1989) and the gypsy moth, Lymantira dispar (Master et al., 1994). The minimum sequence (pentapeptide) required for activity is indicated.

Raina A. K. and Klun J. A. (1984) Brain factor control of sex pheromone production in the female com earworm moth. Science 225, 531-533. 

Raina A. K Jaffe H Kempe T. G Keim P, Blacher R. W Fales H. M Riley C. T Klun J. A., Ridgway R. L. and Hayes D. K. (1989) Identification of a neuropeptide hormone that regulates sex pheromone production in female moths. Science 244, 796-798. 

Clearwater J. R. and Sarafis V. (1973) The secretory cycle of a gland involved in pheromone production in the Noctuid moth, Pseudaletia separata. J. Insect Physiol. 19, 19-28. 

Another technique that is utilized to help ensure that label is incorporated into the pheromone is to apply the precursor at the same time as pheromone biosynthesis activating neuropeptide (PBAN). PBAN is a peptide hormone that regulates pheromone biosynthesis in most, but not all, moths. So, first it must be demonstrated that PBAN regulates pheromone production. In the case of the cabbage looper,... 

Foster S. P. and Roelofs W. L. (1994) Regulation of pheromone production in virgin and mated females of two tortricid moths. Arch. Insect Biochem. Physiol. 25, 271-285. 

In this chapter we will review the current state of knowledge about how pheromone production is regulated in female moths. Discussion of PBAN identification and localization within the nervous system will be followed by how PBAN acts to stimulate pheromone biosynthesis. The final major topic will be a discussion of mediators and inhibitors of PBAN action. A considerable amount of information has accumulated with regard to regulation of pheromone biosynthesis in moths since Pheromone Biochemistry (Prestwich and Blomquist, 1987) was first published, and this chapter is not all inclusive. Further information can also be obtained in several reviews (Raina, 1993 Jurenka, 1996 Teal et al., 1996 Rafaeli et al., 1997b Raina, 1997 Rafaeli, 2002). 

Ando T., Kasuga K., Yajima Y., Kataoka H. and Suzuki A. (1996) Termination of sex pheromone production in mated females of the silkworm moth. Arch. Insect Biochem. Physiol. 31, 207-218. 

Foster S. P. (1993) Neural inactivation of sex pheromone production in mated lightbrown apple moths, Epiphyas postvittana (Walker). J. Insect Physiol. 39, 267-273. 

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