FIGURE 7.
Sestd1 is a novel binding partner of Vangl2 and mutations in Sestd1 and Vangl2 reciprocally rescue. A, Sestd1 interacts with Vangl2 in HEK293T cells. FLAG-Sestd1 was expressed with or without HA-Vangl2 in HEK293T cells. Protein complexes were immunoprecipitated (IP) with anti-HA-agarose beads and associated proteins detected by immunoblot (IB) with anti-FLAG antibody. B, carboxyl terminus of Sestd1, including all three spectrin domains, interacts with Vangl2. Appropriate FLAG- or HA-tagged proteins were recombinantly expressed in HEK293T cells. The co-IP assays were performed as in Fig. 1A. C, schematic summary of complex formation between Sestd1 and Vangl2: Interacting regions are indicated by gray braces. D, loss of Sestd1 partly rescues the semidominant Vangl2Lp phenotype. An intercross was made between Sestd1+/−;Vangl2+/+ and Sestd1+/−;Vangl2Lp/+ mice, and neonatal offspring were genotyped and phenotyped. In the bar graph, the numbers of offspring corresponding to each phenotype/genotype are shown in white. E, heterozygosity for the Vangl2Lp allele partly rescues the Sestd1 null phenotype, graphed as in D.