Figure 4. Group housing enhances the effect of juvenile hormone signaling on Or47b ORN pheromone response.

(A) Juvenile hormone binds to its receptor, Methoprene-tolerant (Met), in Or47b ORNs (left). Red cross indicates RNAi-mediated knockdown of Met. (Right) Effect of Met-knockdown on pheromone responses in Or47b ORNs of males chronically exposed to solvent or palmitoleic acid (PA). SH male flies were exposed to 10 μg PA or solvent for 7 days. n = 13 flies per condition. Odor stimulation: 4.5 ng to 450 μg PA.

(B) Effect of chronic exposure to 0–10 μg PA on Or47b ORN pheromone responses in 7-day and 2-day SH males. Males were treated either with solvent or 2.5 μg of a juvenile hormone analog (JHA, Methoprene). n=18 flies per condition.

(C–E) Or47b ORN pheromone responses in 2-day old male flies treated with 0–25 μg of JHA. Effect of housing condition (C), chronic exposure to 10 μg PA (D) and dCBP knockdown (E) on JHA-dependent enhancement in Or47b ORN pheromone response. n=17–18 flies per condition.

(F) Effect of varying dosage of JHA treatment (0–25 μg) and PA exposure (0–10 μg) on Or47b ORN pheromone responses in 2-day SH males. Heatmap indicates normalized mean evoked response for a given rearing condition. Response for each rearing condition was normalized to that of males with no JHA treatment or PA exposure (bottom left).

(G) Model for interaction between group housing and juvenile hormone signaling pathways.

GH: raised in groups of 15 per vial. SH: raised in isolation. Significant differences are denoted by *, p<0.05; **, p<0.01; ***, p<0.001 (A), or different letters (p<0.05) (B–E) as determined by two-way ANOVA followed by Tukey’s post-hoc test. 45 μg PA was used as the odor stimulus unless specified otherwise. Data are presented as mean ±SEM. Line width in PSTH indicates SEM.