(A) Schematic of Vang protein structure. Green bar depicts conserved cluster of serine and threonine (S/T) residues (sequence shown below) in the intracellular N-terminus.
(B) Western blot analyses of Vang3XFlag point mutants (sequence substitutions shown on right) in S2 cells. Substituting four S/T for Alanine (A) in the C-terminal half of the cluster eliminates Fz induced band shift (upper panel). Substitution of S120/122 for A is the “minimal” mutant that eliminates the Fz induced band shift (lower panel).
(C) Larval lysate from flies expressing tub-VangGFP in a Vang−/− background displays a shifted band on a Western blot, while lysates from tub-VangS2A-GFP; Vang−/− larvae did not produce a band shift.
(D–I) Vang S/T120/122 are essential for Vang function.
(D–F) Adult wings (proximal is left and anterior up): region around L3 and the posterior cross vein is shown. (D) Vang−/− wings show hair misorientation and multiple cellular hair phenotypes. (E) Expression of tub-VangGFP rescues the Vang−/− defects, whereas tub-VangS2A-GFP does not rescue the Vang−/− defects.
(G–I) Adult eye sections, near equator region of indicated genotypes. Dorsal is up and anterior is left, with schematics in bottom panels. (G) A Vang mutant displays chirality defects with symmetrical clusters (green arrows), as well as rotation defects. (F) tub-VangGFP rescues the Vang−/− defects. (G) Expression of tub-VangS2A-GFP fails to rescue the eye PCP defects of the Vang- mutant. Scale bars: 25μm (D–I).