FIGURE 4.

WNT10B induces nuclear transport and binding of RAC1 and β-catenin. A, an approximate 8-fold increase in RAC1 level along with an approximate 6-fold increase β-catenin level were detected in the nuclear fractions precipitated with RAC1 antibody in WNT10B-treated (+) but not in Veh C-treated human CECs. Cotreatment with sFRP, Disheveled-PDZ DI, and the RAC1 inhibitor NSC blocked WNT10B-dependent nuclear transport of RAC1 and its interaction with β-catenin. Inhibition of β-catenin with XAV treatment did not interfere with nuclear transport of RAC1, but β-catenin was not found in the nucleus complexed to RAC1. Cotreatment with RA or the Rho kinase inhibitor Y had no effect on WNT10B-dependent RAC1 nuclear transport and its interaction with β-catenin. The bar graphs depict the relative -fold difference in RAC1 and β-catenin levels. Lamin B and α-tubulin were used as nuclear and cytoplasmic markers, respectively. IP, immunoprecipitation; IB, immunoblot. B, RAC1 but not β-catenin complexed to RAC1 was detected in the cytoplasm under all treatment conditions.