Author
ELTAHLAWY, HANAN - NORTH DAKOTA STATE UNIV. | |
Buckner, James | |
FOSTER, STEPHEN - NORTH DAKOTA STATE UNIV. |
Submitted to: Archives of Insect Biochemistry and Physiology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/20/2007 Publication Date: 5/1/2007 Citation: Eltahlawy, H., Buckner, J.S., Foster, S.P. 2007. Regulation of pheromone biosynthesis in the "Z strain" of the European corn borer, Ostrinia nubilalis. Archives of Insect Biochemistry and Physiology. 65(1):29-38. Interpretive Summary: Sexual communication in moths is mediated mainly by sex pheromones, which are volatile compounds used by female moths to attract potential mates from long distances. Most moth sex pheromone compounds are derived from fatty acids. The female makes sex pheromone in a specialized gland, near the tip of the abdomen. Sex pheromone production in many moths is under the control of a pheromone biosynthesis activating neuropeptide (PBAN), a hormone produced in the brain. PBAN works by affecting one or more enzymatic steps in the pheromone biosynthetic pathway. The regulation of pheromone biosynthesis by PBAN in the Z strain of the European corn borer, Ostrinia nubilalis, was investigated using labeled intermediates. Injection of radiolabeled acetate showed PBAN did not influence the synthesis of saturated fatty acids in the gland. Deuterium, a non-radioactive isotope of hydrogen, was used to label the fatty acid, myristic acid. When the deuterium-labeled myristic acid was topically applied to the gland, females injected with PBAN produced more labeled pheromone than did control females, indicating that PBAN controls one of the later steps of pheromone biosynthesis. Although more myristic acid was desaturated (converted to double-bond compound) in the gland in the presence of PBAN, this was counterbalanced by less desaturation of palmitic acid, indicating that the enzyme (desaturase) activity did not change overall. This change in flux of myristic acid through to pheromone was shown to be caused by increased reduction of fatty acid pheromone precursors occurring in the presence of PBAN. Technical Abstract: The regulation of pheromone biosynthesis by the neuropeptide PBAN in the Z strain of the European corn borer, Ostrinia nubilalis, was investigated using labeled intermediates. Injection of radiolabeled acetate showed PBAN did not influence the de novo synthesis of saturated fatty acids in the gland. When deuterium-labeled myristic acid was topically applied to the gland, females injected with PBAN produced more labeled pheromone than did control females, indicating that PBAN controls one of the later steps of pheromone biosynthesis. Although more myristic acid was '11-desaturated in the gland in the presence of PBAN, this was counterbalanced by less '11-desaturation of palmitic acid, indicating that desaturase activity did not change overall. This change in flux of myristic acid through to pheromone was shown to be caused by increased reduction of fatty acid pheromone precursors occurring in the presence of PBAN. |