Figure 5.

The extracellular domain of PCDHB13 regulates microtubule polymerization. (A) Schematic showing the functional domains of PCDHB13. Recombinant proteins with EC1–EC3, EC1–EC6, and CR of PCDHB13 were used for the in vitro tubulin polymerization assay. (B–D) Dynamic assessment of the effects of PCDHB13 domains on microtubule polymerization. Pure tubulins were assembled in the presence of indicated amounts of CR domain (B) or EC domains (C,D). Tris-HCl-10% DMSO, paclitaxel, and nocodazole served as vehicle, positive control, and negative control, respectively. (E) Fluorescent tubulins were used to probe the formation of microtubules in the presence of PCDHB13 EC domains. Boxed regions are magnified in the panels to the left. Bar: 20 μm. Three wells were analyzed for each independent replicate. Quantitative results are presented as the mean ± SD (n = 3).