Regulation of cricket phonotaxis through hormonal control of the threshold of an identified auditory neuron

Abstract

1. The phonotactic threshold of 3 to 5-day-old adult female Acheta domesticus and the threshold of the L1 auditory neuron drop progressively (Fig. 1). 2. Application of juvenile hormone III (JHIII) to 1-day-old females caused both the female's threshold for phonotaxis and the threshold of the L1 auditory neuron to drop 20 or more dB over the next 12 h (Figs. 3-4). 3. JHIII's effect on phonotactic threshold could be blocked by injection with a transcription (alpha-amanitin) or a translation blocker (emetine, Fig. 3). 4. Injection of emetine also prevented the JHIII induced drop in L1's threshold (Fig. 4). 5. Application of JHIII to the surface of, or microinjection of JHIII into one prothoracic hemiganglion caused the female to circle phonotactically away from the side of hormone addition at thresholds 25 to 35 dB lower than the pre-JHIII addition threshold within 2 h (Fig. 6). 6. Application of JHIII to the surface of both prothoracic hemiganglia, accompanied by microinjection of emetine into one hemiganglion resulted in the female emetine into one hemiganglion resulted in the female circling phonotactically toward the side receiving emetine injection, with a 25 to 35 dB drop in threshold (Fig. 6).

Juvenile Hormone, Behavioral Maturation, and Brain Structure in the Honey Bee

“…The link of JH to the reproductive cycle and mating behavior in adult female insects has suggested that JH may also act on the central nervous of hemimetabolous insects (insects that, unlike bees, moths, and flies, do not undergo complete metamorphosis with an intervening pupal stage). This hypothesis is well sup ported by recent studies showing that JH stimulates adult neurogenesis in the mushroom bodies of the house cricket [Cayre et al, 1994], and that direct application of JH to thoracic ganglia can very quickly change the response of female crickets to male courtship song [Stout et al, 1991]. Some aspects of migratory flight in the milkweed bug, Oncopeltus fasciatus, are controlled by the corpora allata [Rankin and Riddiford, 1977;Rankin, 1980], JH also plays a role in the regulation of pheromone-mediated calling behavior in armyworm moths [Cusson and McNeil, 1989;Cusson et al" 1994], A recent study used RIA to demonstrate rapid modula tion of JH titers in adult female burying beetles as they assess the quality of potential sites for oviposilion, sug gesting a possible role in this species in mediating the acquisition of information directly related to reproduc tive success [Trumbo et ah, 1995].…”

Effect of juvenile hormone on the central nervous processing of sex pheromone in an insect

“…Age-dependent plasticity in adult brain structure was previously shown in social insects (19,20), and an influence of JH on neurogenesis in the brain was found in crickets (3). JH also was shown in crickets to act on the sensitivity of auditory interneurons controlling phonotaxis (21). In mammals, gonadal steroids have been shown to control the behavioral responses to pheromones by actions on the central nervous system (22).…”

Juvenile hormone in adult eusocial hymenoptera: Gonadotropin and behavioral pacemaker

“…Similarly, JH has been shown to regulate neurogenesis in the brain of the cricket, Acheta domesticus (Orthoptera: Gryllidae; Cayre et al, 1994). JH may also influence other aspects of brain function, such as the electrophysiological properties of some neurons (Stout et al, 1991) or levels of peptide and biogenic amine neuromodulators. Progress in determining the relationship between JH and the central nervous system is hampered by a poor understanding of JH receptors.…”