Fig. 1.

Cleavage of cadherin-11 is essential for CNC migration in vivo. (A) Western blot from showing cleavage of C11 by ADAM13 but not by the inactive ADAM13-E/A containing a mutation in the active site. Glycoproteins were purified from transfected Cos-7 cells with ConA-agarose beads and detected using the antibody to the cadherin-11 cytoplasmic domain 1B4. Cleavage is observed by the presence of a shorter membrane-bound C11 fragment at 65 kDa (arrowhead). This cleavage fragment is absent when C11-egf is co-transfected with ADAM13. ADAM13 was detected using the antibody to the ADAM13 cytoplasmic domain 6615 F. The 120 kDa Pro-form and the 100 kDa mature form are shown. B–D) Targeted injection assays testing non-cleavable C11-egf in CNC migration in vivo. Histograms represent the percentage of embryos with no CNC migration, normalized to injection of RFP alone, for the overexpression of C11 or C11-egf with A13 or A13-egf (B) or the replacement of endogenous C11 with wildtype or non-cleavable C11-egf (C). Representative images of embryos in (C) are shown in (D) with arrowheads pointing to RFP-labeled cells that successfully migrated into the branchial and hyoid arches. n=number of embryos scored from three or more independent experiments. Error bars represent standard deviation to the mean. Student's t-test was performed to determine statistical significance. *p < 0.05, ***p < 0.005. Scale bar, 500 μm.