Figure 7. Dopamine elevates egg-laying in a GABA-dependent manner.

(A) Effects of dat-1::CoChR activation in genetic mutants with disrupted components of egg-laying circuitry. Data are shown as the fold increase in egg-laying during lights-on period, compared to lights-off period (a value of 1 indicates no effect of the light on egg-laying). *p<0.05, Mann-Whitney U test. n = 9–35 animals per genotype. (B) Two independent null mutants lacking unc-25, which is required for GABA synthesis, have an altered profile of egg-laying. Data are shown as average eggs laid per day, with the first day being the first 24 hr after L4. *p<0.05 and **p<0.01, effect of genotype in two-factor ANOVA and post-hoc pairwise Dunnett test. n = 5–10 animals per genotype. (C) Percent of eggs laid during roaming and dwelling for two independent null mutants of unc-25, which are defective in GABA synthesis. Here, we display data in this format to normalize for the reduced brood size in unc-25. *p<0.05, Mann-Whitney U test. **p<0.001, Mann-Whitney U test. n = 11–30 animals per genotype. (D) Egg-laying in the absence of food is elevated in unc-25 mutants. Data are shown as a ratio of eggs laid off food divided by eggs laid on food. **p<0.01 and †p<0.1 in ANOVA and post-hoc pairwise Dunnett test. n = 5–6 plates per genotype, each with 10 animals per plate.