Figure 2.

The FZD₄ C-tail modulates surface expression and receptor-DVL interaction. (A) V5mFZD₄ variants were overexpressed in HEK293 cells with hLRP5 and M50 reporter plasmid, stimulated with Norrin and Lef/Tcf-dependent luciferase activity was assayed as described. (B) Cell surface receptor expression detected by IFA in HEK293 cells transfected with the V5mFZD₄ variant shown and hLRP5. Following fixation the non-permeabilized cells were incubated with V5 primary antibody followed by incubation with a compatible Alexafluor594 secondary antibody and subsequent fluorescence quantification on a multimode plate reader. Statistically significant differences compared to WT as determined by an ANOVA analysis followed by the Dunnett’s post hoc test is indicated with an asterisk (*). (C) Confocal images of non-permeabilized HeLa cells co-transfected with GFP-tagged DVL2 and V5mFZD₄ WT or truncation variants using a V5 primary antibody.