The Cul1-based SCF E3 ligase complex governs ddaC dendrite pruning in a Mical-independent pathway.

<p>(A–D) Confocal images show Mical stainings (in red) in various genotypes of ddaC neurons expressing <i>UAS-mCD8-GFP</i> driven by <i>ppk</i>-<i>Gal4</i> at WP. ddaC somas are marked by dashed lines, and ddaE by asterisks. The Mical expression in ddaC neurons of wild type (A), <i>cul1 RNAi</i> (B), <i>roc1a^G1</i> MARCM (C), and <i>skpA</i> RNAi (D) remained largely unchanged. (E) Quantification of immunostaining for Mical was performed as described in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001657#s4" target="_blank">Materials and Methods</a>. The graph displays the average values of ddaC/ddaE ratios and S.E.M—n.s., not significant. <i>n</i> is shown on the bars. (E) The scale bar in (A) is 20 µm. (F–I′) Live confocal images of ddaC neurons expressing <i>UAS-mCD8-GFP</i> driven at WP and 16 h APF. (F and G) Although WP morphology remained largely unchanged, MARCM ddaC clones of <i>cul1^EX</i> and <i>sox14^Δ13</i> double mutant exhibited dendrite pruning defects with an average of 15.2 primary and secondary dendrites attached (G′), similar to either <i>cul1^EX</i> (<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001657#pbio-1001657-g001" target="_blank">Figure 1E′</a>) and <i>sox14^Δ13</i> (F′) single mutant. (H and I) Although WP morphology remained unchanged, MARCM ddaC clones of <i>mical¹⁵²⁵⁶</i>, <i>slimb⁸</i> double mutants exhibited a significant enhancement of ddaC dendrite pruning defects (I′), compared to either <i>slimb⁸</i> (<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001657#pbio-1001657-g003" target="_blank">Figure 3E′</a>) or <i>mical¹⁵²⁵⁶</i> (H′) single mutants. (J and K) Quantification of the average number of primary and secondary dendrites attached to the soma of mutant ddaC neurons at 16 h APF. The number of samples (<i>n</i>) in each group is shown on the bars. **<i>p</i><0.01, ***<i>p</i><0.001, n.s., not significant. Error bars represent S.E.M. Dorsal is up in all images. The scale bar in (F) is 50 µm. See genotypes in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001657#pbio.1001657.s023" target="_blank">Text S1</a>.