Wnt signaling regulates isoform expression of OSBPL1A and TRAK1. A, OSBPL1A isoform ratio measured by qRT-PCR in DLD1 and Ls174T cells expressing either dnTCF1 or dnTCF4 to disrupt the Wnt pathway. B, OSBPL1A isoform ratio in DLD1 cells transfected with either 20 nM control or β-catenin siRNA. C, TRAK1 exon 1A/1B ratio as described in A, D, TRAK1 exon 1A/1B ratio as described in B. * = p < 0.05, ** = p < 0.01 and *** = p < 0.001.