Phosphorylation-Dependent Ubiquitination of Paraxial Protocadherin (PAPC) Controls Gastrulation Cell Movements
Figure 2
Phosphorylation of PAPC by GSK3 at the DSR domain is required for PAPC regulation.
(A) Evolutionarily conserved domain of PAPC in the cytoplasmic region. This domain is rich in aspartic acid and serine and is referred to as the DSR domain. The sequence of mutants used in this study (SA1, SA2) is also indicated. (B) PAPC; wild-type PAPC tagged with GFP, PAPC-SA1; a putative non-phosphorylated mutant in which S816 and S820 are replaced with alanine, PAPC-SA2; S830, S832, T834, S835 and S838 are replaced with alanine. mRNAs encoding these proteins were injected into the animal pole of Xenopus laevis embryos. Animal caps were dissected and observed under a microscope. (C) PAPC-SA1 mRNAs were injected into the dorsal marginal zone. The mutant was maintained in the DMZ explant at stage 15 when wild-type PAPC is mostly degraded.