Figure 4

The frequency of DD/VD axon defects along the length of the animal is correlated with the size of the muscle that the axon traverses. (A) Dorsal lateral muscle cells (white) are labeled according to their numerical identity²⁰. The regions R1 to R12, labeled in orange, are determined by the location of the muscle cell or cells that the axon traverses, and boundaries of each region are labeled in blue. Scale bars indicate 50 μm. (B) Model of C. elegans with dorsal lateral muscle overlayed by DD/VD neuron axons. Dorsal lateral muscle is depicted in a layered fashion in order to fit all 9 muscles. Below each muscle identity (muscles 8 to 24) is the average longitudinal area of each muscle (see Fig S2). DD/VD commissural axon identities are indicated, and the axon error rate for each axon is displayed. Below each axon identity, the muscle(s) traversed by the axon is indicated, and the represented region R1 to R12 is shown. (C) The longitudinal area of muscle cells (left Y axis, red line) in each region from the anterior side (R1) to the posterior side (R12) are plotted together with the average rate of axon defects (right Y-axis, purple line) in each region. Correlation (R²) for the two sets of data was calculated by regression analysis as 0.81. Error bars indicate standard error.