Redbanded leafroller moth

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). 

Bjostad L. B. and Roelofs W. L. (1981) Sex pheromone biosynthesis from radiolabeled fatty acids in the redbanded leafroller moth. J. Biol. Chem. 256, 7936-7940. 

Miller J. R. and Roelofs W. L. (1980) Individual variation in sex pheromone component ratios in two populations of the redbanded leafroller moth, Argyrotaenia velutinana. Envir. Entomol. 9, 359-363. 

Roelofs W. L., Du J.-W., Linn C. E., Glover T. J. and Bjostad L. B. (1986) The potential for genetic manipulation of the redbanded leafroller moth sex pheromone blend. In Evolutionary Genetics of Invertebrate Behavior, ed. M. D. Heuttel, pp. 263-272. Plenum Press, New York. 

Roelofs W. L. and Jurenka R. A. (1996) Biosynthetic enzymes regulating ratios of sex pheromone components in female redbanded leafroller moths. Bioorganic Med. Chem. Letters 4, 461 4-66. 

Sreng I., Glover T. and Roelofs W. (1989) Canalization of the redbanded leafroller moth sex pheromone blend. Arch. Insect Biochem. Physiol. 10, 73-82. 

Z11-14 Acid and 11-14 Acid are the only unsaturated pheromone intermediates of the redbanded leafroller moth, Argyrotaenia velutinana (Bjostad and Roelofs, 1981). Stable isotope experiments showed that the mixture of these unsaturated... 

One insect proved to be of special interest and was studied in greater detail (5-6). The redbanded leafroller moth (RBLR), Argyrotaenia velutinana, uses (Z)- and (E) -11—tetradecenyl acetates as pheromone components in the ratio of 9 1. The pheromone glands of these insects also contained the corresponding acids, All-tetradecenoic acids, but the Z to E ratio was about 4 5. If these acids serve as precursors to the acetates, there must be strict stereochemical control exercised in the reactions that produce the final product in the 9 1 ratio. 

The redbanded leafroller moth uses a mixture of (E) and (Z) -11-tetradecenyl acetates as pheromone components. The pheromone gland of this insect also contains an acetyl Co A fatty alcohol acyl transferase (22.). This enzyme will acetylate 12, 14 and 16 carbon alcohols, and prefers the saturated alcohol to the Z monounsaturated derivative, and the Z to the E, in the approximate ratios of 5 3 1 for saturated, Z and E, respectively. 

In the redbanded leafroller moth, treatment of intact glands with DMSO containing radioactive acetate led to the formation of radiolabeled 14, 16 and 18 carbon saturated acids as well as All-tetradecenoic acids and pheromone components (12). Cell-free preparations from redbanded leafroller pheromone glands also showed FAS activity when radiolabeled acetyl Co A, NADPH and malonyl Co A are supplied (21). The major products are the 16 and 18 carbon saturated acids, with the 18 carbon acid predominating. 

Finally, although the All desaturase from cabbage looper is probably the most studied enzyme involved in these pathways, much more work should be done with it and related enzymes. For example, it only produces Z products and does not function efficiently with 14 carbon substrates, indicating a fundamental difference with the enzyme from redbanded leafroller moths, which desaturates 14-carbon acids to give a mixture of Z and E product (22). Projects such as this may well prove technically difficult, but will provide great insight into the enzymatic mechanisms. 

O Connell, R. J. (1975) Olfactory receptor responses to sex pheromone components in the redbanded leafroller moth. J. gen. Physiol., 65, 179-205. 

Taschenberg, E. F, and W. L. Roelofs Male redbanded leafroller moth orientation disruption in vineyards. Envir. Entomol. 7, 103—106 (1978). 

The ability of male moths to perceive mixtures of geometric isomers with extraordinary acuity was further documented in an investigation of the responses of males of the redbanded leaf-roller and two populations of the European cornborer to isomers of 11-tetradecenyl acetate (21). Redbanded leafroller males were essentially unresponsive to pure preparations of their reported sex pheromone, (Z)-11-tetradecenyl acetate, but were strongly attracted to lures containing up to 8% of the (E)-isomer. Similarly, European cornborer males from Iowa responded maximally when 4% of the (E)-isomer was added to the (Z)-isomer, whereas the New York population was attracted to an isomeric mixture containing about 4% of the (Z )-isomer. Enhanced attraction by a small proportion of the opposite geometric isomer was also demonstrated with males of the oriental fruit moth,... 

Population control by mass trapping in low populations has been demonstrated for the redbanded leafroller (RBLR), Argyrotaenia velut-inana, in apple orchards and vineyards, and for the grapeberry moth (GBM), Paralobesia viteana, in vineyards. However it was concluded that the benefits relative to cost could not justify this means of control, and research was diverted to mating disruption programs. 

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