Fig. 2.

mec-10 mutants have reduced touch-evoked calcium transients in ALM touch neurons. A: stimulus positions for imaging experiments. Animals expressing cameleon in touch neurons were given a 1-s gentle (buzz) stimulus at the indicated position, as described in methods. B–E: averaged calcium responses of wild-type (B), mec-10(tm1552) (C), mec-10(u20) (D), and mec-4(u253) (E) mutants. Each red trace represents the average percentage change in R/R₀, where R is the fluorescence emission ratio at a given time point and R₀ is its initial value. The number of individual recordings averaged for each trace were n = 27, 23, 22, and 12 (wild-type, positions 3, 2, 1, and −1, respectively); n = 20, 25, 25, and 8 (mec-10(tm1552), positions 3, 2, 1, and −1, respectively); n = 20 [mec-10(u20), all positions]; and n = 10, 10, 8, and 8 (mec-4, positions 3, 2, 1, and −1, respectively). Gray shading indicates SE of the mean response. Scale bars are indicated in the top left. The green bar indicates the time of the stimulus. Decreases in the u20 ratio signal (e.g., at position −1) are not accompanied by reciprocal changes in yellow fluorescent protein (YFP) and cyan fluorescent protein (CFP) emission intensities, suggesting that they are probably motion artifacts. F: scatterplot of peak calcium responses for each genotype. Red lines indicate the mean response at each of the 4 stimulus points; error bars indicate SE. Every other line indicates the response for a single animal. Half the animals were stimulated from anterior to posterior and half from posterior to anterior. One-way ANOVA demonstrated a statistically significant difference in the responses of mec-10 but not mec-4 animals at different positions along the anteroposterior axis (P < 0.001).