Figure 2

β-catenin/TCF4 is directly involved in p68 expression. (a) MCF7 cells were transfected with 1 and 2 μg of pEGFP-β-catenin. Expressions of p68 and β-catenin target Cyclin D1 were analysed by immunoblotting (IB) with whole cell lysates (WCLs) prepared from 36 h post-transfected cells. (b, c) MCF7 cells transfected with pEGFP-β-catenin. After 36 h, cells were kept in the presence of either translational (CHX) or transcriptional (AD: actinomycin D) inhibitors for another 6 h and analysed by IB and qRT-PCR for expression of p68 and cycinD1 genes. Densitometry values are given below the blots for IB. Exo and endo refers to the exogenous and endogenous band of β-catenin respectively. (d, e) 4T1 and HEK293T cells were transfected with either β-catenin or tcf4. WCLs prepared from 36 h post-transfected cells and expressions of target genes, as shown in the figure, were determined by IB using respective antibodies. Densitometry values are given below the blots. (f) HEK293T cells were transfected with either WT-TCF4 or DN-TCF4, and expressions of p68 and β-catenin target cMyc were analysed by IB with WCLs prepared from 36 h post-transfected cells.