Receptivity termination factor

Raina A. K., Bird T. G. and Giebultowicz J. M. (1990) Receptivity terminating factor in Heliothis zea and its interaction with PBAN. In Insect Neurochemistry and Neurophysiology, eds A. B. Borkovec and E. P. Masler, pp. 299-302. Humana Press Inc., Clifton Springs, NJ. 

During the course of the studies with the corn earworm receptivity termination factor, it became obvious that asignifleant amount of variation was inherent in the bioassay methods. Essentially, each female responds differently to the PBAN titer injected. This, coupled with the variable reduction in the titer due to the presence of the RTF, causes a highly variable response in pheromone levels. 

It is imperative to demonstrate whether JH HI operates directly on pheromone glands or whether it facilitates the activity of other pheromonotropic regulators. Studies of mated females, which produce JH III but not pheromone, have made it abundantly clear that unknown regulatory elements downstream of the action of JH must be involved. These factors probably interact with inhibitory signals from the terminal abdominal ganglion that ascend the VNC and control CNS activity. A concerted effort is needed to identify neuropeptides and other factors that activate and terminate pheromone production, emission, and sexual receptivity. 

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