<i>kpc-1</i> serves a function in dendritic self-avoidance.

<p><b>A</b> Epifluorescent micrographs of a lateral view of wild type and <i>kpc-1(dz185)</i> hypomorphic animals. Filled white arrowheads indicate axons and empty white arrowheads gaps between tertiary dendrites, which are known to be maintained by self-avoidance <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004657#pgen.1004657-Smith3" target="_blank">[33]</a>. Scale bar is 20 µm. <b>B</b> Quantification of self-avoidance index which was determined as previously described <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004657#pgen.1004657-Liu1" target="_blank">[34]</a> and is defined as the ratio of the number of gaps between adjacent tertiary branches divided by the number of candelabra in a 100 µm segment anterior to the cell body. Statistical comparisons were performed using the Student t-test and statistical significance is indicated (****, <i>P</i>≤0.0001). <b>C</b> Maximum intensity projection of a Z-stack (lateral view of a <i>kpc-1(dz815)</i> mutant shown in A) in which each optical section (total of 12 sections over 7.2 µm equaling 0.6 µm/section) was color-coded with warmer to colder colors for medial to lateral sections of the animal, respectively. Note that the overlapping tertiary dendrites appear in the same focal plane. Since the width of dendritic branches is approximately 200 nm <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004657#pgen.1004657-Albeg1" target="_blank">[35]</a>, these data suggest that tertiary dendrites are closely apposed (within 0.6 µm) or directly touching. An asterisk marks an area of the cell body that is saturated due to maximum intensity projection.