Overexpression of FLP-18 causes uncoordinated locomotion, frequent reversals, and excessive bending, which is suppressed in an npr-5 mutant background. (A-B) Quantification of omega turning behavior. (A) Percentage of animals that execute omega turns in response to gentle anterior touch. (B) Fraction of open omega turns out of total omega turns. (C and D) Mean body curvature averaged over 5 seconds prior to a tap stimulus (C) or immediately following a strong tap stimulus (D). (E) Percentage of animals suppressing head movements in response to gentle anterior touch with an eyelash. (F and G) Omega turning behavior in FLP-18 overexpressors. (F) Percentage of animals initiating omega turns after gentle anterior touch. (G) Proportion of open omega turns out of total omega turns. (H) Mean number of spontaneous reversals per minute per worm averaged over 3 minutes. Graphs represent mean ± SEM, significance was calculated using ANOVA with Šidák’s multiple comparison correction (P> 0.05 = ns, P<0.05 = *, P<0.005 = **, P<0.0005 = ***, P<0.0001 = ****). Sample sizes (n = # of experiments, 20 animals per experiment): Omega turn quantification (A and B) wild type (n = 21), flp-18 (n = 21), npr-1 (n = 12), npr-4 (n = 14), npr-5 (n = 21). Curvature and reversal measurements (C, D, and H) wild type (n = 46), FLP-18(+++) (n = 33), npr-1; FLP-18(+++) (n = 23), npr-4; FLP-18(+++) (n = 27), npr-5; FLP-18(+++) (n = 23). Suppression of head movements and omega turn quantification (E-G) wild type (n = 22), FLP-18(+++) (n = 10), npr-1; FLP-18(+++) (n = 12), npr-4; FLP-18(+++) (n = 10), npr-5; FLP-18(+++) (n = 10).