Fig. 9
Lurap1 interacts with Dvl and JNK in Wnt/PCP signalling. The ATF2 and AP1 luciferase reporters were used to monitor Wnt/PCP activity changes in zebrafish and Xenopus embryos, respectively. a ATF2-luciferase reporter assay in WT and MZlurap1 embryos at 80% epiboly stage. An increase of ATF2 reporter activity is detected in MZlurap1 embryos, which is enhanced by caJNK, and blocked by dnJNK. Bars represent the mean values ± s.d. from three independent experiments (*P < 0.05; NS, not significant; Student’s t-test). b Overexpression of Lurap1, but not Lurap1ΔC, inhibits the ATF2 reporter activity in WT zebrafish embryos. Bars represent the mean values ± s.d. from six independent experiments (*P < 0.05; **P < 0.01; NS, not significant; Student’s t-test). c Knockdown of dvl2 and dvl3a suppresses ATF2 reporter activation in WT and MZlurap1 embryos. Bars represent the mean values ± s.d. from three independent experiments (*P < 0.05; **P < 0.01; ***P < 0.01; NS, not significant; Student’s t-test). d Analysis of the functional interaction between Lurap1 and Dvl using AP1 reporter in Xenopus dorsal mesoderm explants. Overexpression of Lurap1, but not Lurap1ΔC, suppresses Dvl-mediated increase of AP1 reporter activity. Bars represent the mean values ± s.d. from three independent experiments (**P < 0.01; ***P < 0.001; NS, not significant; Student’s t-test). e A proposed model of Lurap1 function in regulating Wnt/PCP signalling and cell polarity. Localised cytoplasmic Lurap1 binds to the PDZ domain of Dvl through its PDZ-binding motif, and prevents Dvl from being recruited to the plasma membrane to activate downstream effectors
