Fig. 3: ASIC-1 and DEL-1 form mechanoreceptors in VA and VB.

a Diagram showing how a stimulation pipette was positioned so that stimuli could be delivered to specific regions of a neuron. b Relationship between the mechanoreceptor currents (MRCs) and stimulation pipette location in VA5 and VB6. n = 8 for all data points of VA5 and 10-11 for data points of VB6. c MRCs in VA and VB differ from those in DA and DB stimulated at the soma. Shown are sample traces (top) and comparisons of peak MRC and sustained MRC (bottom). d MRCs in VB6 are eliminated by either application of amiloride or substitution of extracellular Na⁺ by choline⁺ or NMDG⁺. e, f Mutations of asic-1 and del-1 impair MRCs in VB6 and VA5. Wild-type asic-1 and del-1 were expressed in ventral nerve cord cholinergic motor neurons using Punc-17Δ1 in the rescue experiments. WT = wild type. g Expression of del-1 is detected in VA and VB, and that of asic-1 in additional neurons, including D-MNs, CEP, ADE, PDE, FLP, and PVD, in animals co-expressing Pdel-1::mStrawberry and Pasic-1::GFP transcriptional fusions. A similar pattern is observed in 23 animals. Scale bar = 50 μm. *, and *** indicate p < 0.05 and p < 0.001, respectively (one-way ANOVA with Tukey’s post hoc test). For peak MRC, p = 0.8778, 0.9119, and 0.6783 (compared with VA5, c), 0.9943, 0.9946, 0, < 0.0001, and < 0.0001 (compared with control, d), 0.0117, 0.9999, 0.2598, 0.9663, < 0.0001, and 0.9911 (compared with WT, e), 0.0293 (asic-1 vs asic-1 rescue, e), 0.0003 (asic-1;del-1 vs double rescue, e), 0.0001, 0.9995, 0.6708, 1, < 0.0001, and 1 (compared with WT, f), 0.0002 (asic-1 vs asic-1 rescue, f), < 0.0001 (asic-1;del-1 vs double rescue, f). For sustained MRC, p = 0.9789, < 0.0001, and < 0.0001 (compared with VA5, c), 1, 1, < 0.0001, < 0.0001, and 0.0005 (compared with control, d), 0.2841, 0.9998, < 0.0001, 0.9999, < 0.0001, and 1 (compared with WT, e), 0.0005 (del-1 vs del-1 rescue, e), < 0.0001 (asic-1;del-1 vs double rescue, e), 0.2127, 0.9929, 0.0008, 0.9872, < 0.0001, and 0.9983 (compared with WT, f), 0.0392 (del-1 vs del-1 rescue, f), < 0.0001 (asic-1;del-1 vs double rescue, f). Brackets contain the number of cells recorded. Data are shown as means ± SEM. Source data are provided as a Source Data file.