Showing papers by "Nianbai Fang published in 1995"
TL;DR: Manduca sexta females that were decapitated produced no pheromone during the scotophase following decapitation, indicating that they were free of phersomone biosynthesis activating neuropeptide (PBAN), which activates the process by which fatty acyl precursors in the pheromonal aldehydes are converted into the phersomonal fatty acids.
Abstract: Manduca sexta females that were decapitated produced no pheromone during the scotophase following decapitation, indicating that they were free of pheromone biosynthesis activating neuropeptide (PBAN). When deuterated hexadecanoic or (Z)-11-hexadecenoic acid was applied to the sex pheromone glands of decapitated or intact females of the same age, and allowed to incubate in vivo for 24 h, deuterium labeled Δ-11- and Δ-10, 12-unsaturated 16-carbon fatty acids were produced in both types of females. Injection of PBAN into intact or decapitated females 23 h after application of labeled acids had no effect on the production of unsaturated labeled fatty acids. However, deuterium labeled aldehydes were produced only in females that were injected with PBAN. Therefore, in this species, PBAN activates the process by which fatty acyl precursors in the pheromone gland are converted into the pheromonal aldehydes. © 1995 Wiley-Liss, Inc.
38 citations
TL;DR: An oxidase that converts primary aliphatic alcohols into aldehydes was discovered in the cuticle of the sex pheromone gland and in the papillae anales on the tip of the abdomen of Manduca sexta females.
Abstract: An oxidase that converts primary aliphatic alcohols into aldehydes was discovered in the cuticle of the sex pheromone gland and in the papillae anales on the tip of the abdomen of Manduca sexta females. Oxidase activity was not found in the epidermal cells of the pheromone gland where fatty acid precursors of the pheromonal aldehydes are found. This oxidase requires oxygen and water to function and appears to have a rather broad substrate specificity. The activity of the oxidase is reduced by the application of piperonyl butoxide, which also interferes with the PBAN induced production of the natural pheromone aldehydes. However, endogenous alcohols cannot be found in the pheromone gland. Thus, it is not yet clear whether or not the oxidase is involved in the terminal step of biosynthesis of the pheromone aldehydes in M. sexta females. © Wiley-Liss, Inc.1
22 citations
TL;DR: The proportions of fatty acids bound to certain triacylglycerols regulates the proportions of aldehydes in biosynthesis of the pheromone blend in M. sexta.
Abstract: Analysis by TLC and HPLC revealed that the triacylglycerols comprise the most abundant lipid class in the sex pheromone glands of Manduca sexta females. Also, conjugated olefinic acyl analogs of the major pheromone aldehydes occur principally in the triacylglycerols. The amount of triacylglycerols with conjugated diene acyl moieties significantly decreased when the period of pheromone production was extended by 7 h beyond the normal period of pheromone production by 3 injections of pheromone biosynthesis activating neuropeptide (PBAN) at 3 h intervals. This decrease indicates that the triacylglycerols stored in the gland may serve as major sources of pheromone precursors in the biosynthesis of the sex pheromone aldehydes. Furthermore, analysis of pheromone aldehydes and triacylglycerols in the gland from moths treated with PBAN showed that the proportions of the triacylglycerols with conjugated diene moieties were closely correlated with the proportions of aldehydes found in the same gland. This correlation suggests that the proportions of fatty acids bound to certain triacylglycerols regulates the proportions of aldehydes in biosynthesis of the pheromone blend in M. sexta. © 1995 Wiley-Liss, Inc.1
17 citations