Figure 4. Locomotory behaviors of mechanosensary defective mutants.

(a-d) Curving rates for forward runs (a), non-planar deviations (NPDs) of 3-D posture (b), speeds (c), and reorientation frequencies (d) of indicated strains (n = 18 and 14 for wild-type; n = 17 and 14 for mec-4(e1339); n = 15 and 11 for mec-10(e1515); n = 20 and 24 for osm-9(ky10); n = 26 and 30 for trpa-1(ok999); and n = 16 and 11 for trp-4(sy695) mutants for 2-D and 3-D experiments, respectively). The reorientation frequencies¹⁰ were significantly reduced in 3-D compared to those in 2-D for osm-9 and trp-4 mutants while showing little differences for wild type and mec-4, mec-10 and trpa-1 mutants. In addition, we found that ocr-2(ak47) and glr-1(n2461) mutants, which are defective in OSM-9-mediated mechanosensation³¹,²⁶, also showed reduced reorientation frequencies in 3-D environments (Supplementary Fig. 6). (e) Reorientation frequencies of wild-type, trp-4(sy695) and trp-4(sy695) mutant animals expressing trp-4 in DVA neuron driven by a twk-16 promoter or in dopaminergic neurons driven by a dat-1 promoter²⁴ (n = 9 and 16 for wild-type; n = 26 and 21 for trp-4 mutants; n = 25 and 28 for trp-4(sy695); Ptwk-16(DVA)::trp-4; and n = 27 and 25 for trp-4(sy695); Pdat-1::trp-4 for 2-D and 3-D experiments, respectively). Statistical analysis was performed to compare mutants with wild-type animals (a-b) or between 2-D and 3-D data (c-e) (*p < 0.005, **p < 0.001, ***p < 0.0005, Mann-Whitney U-test). Error bars represent SEM.