IQGAP1 activates β-catenin transcription and promotes its translocation to nucleus.
(A) IQGAP1 overexpression by transfecting with pFlag-IQGAP1 plasmids (flag-IQ) upregulated β-catenin mRNA level. Transfection with empty pCMV6 plasmids was taken as a control. And the mRNA level of c-myc, cyclin D1 and Axin2 upon IQGAP1 overexpression was shown in (D). (B) IQGAP1 knockdown, by specific siRNA for IQGAP1 (si-IQ), decreased β-catenin mRNA level. Transfection with non-target siRNA was taken as a control (si NC). (C) IQGAP1 activates β-catenin transcription by a luciferase promoter analysis. (E) The overexpression of IQGAP1 induced β-catenin translocation from cytoplasm to nucleus. LMNB1 was a nuclear protein control. GAPDH was a cytoplasmic protein control. ** Student’s t test p<0.01, *** Student’s t test p<0.001.