Figure 7. Identification of ∆Np63 as a molecular target involved in Ring1B-sustained Fak expression.

A. Analysis of ∆Np63 expression in cells depleted from Ring1B, detected by western blot analysis of nuclear extracts and qRT-PCR. *, P < 0.05. B. Cells depleted from Ring1B displayed an impoverishment of ∆Np63 promoter ubiquitination, as determined by chromatin immunoprecipitation (ChIP) of MCF7 cells transfected with GFP-tagged ubiquitin and oligofected with mock or Ring1B siRNA. Graph displays percentage of Ub-GFP recruitment to ∆Np63 promoter relative to input values and expressed as mean ± SD of two independent experiments. C. Ectopic ∆Np63 represses Fak expresion in transiently transfected MCF7 cells, as shown by western blot analysis and qRT-PCR. D. Effect of Ring1B dowregulation on Fak expression in cells oligofected with p63 siRNA, detected by western blot. E. Tgfβ represses ∆Np63 expression in MCF7 and MDA-MB-231 cells and induces ubiquitination of endogenous ∆Np63 promoter in MCF7 cells transiently transfected with GFP-tagged ubiquitin, as detected by ChIP. Graph displays percentage of GFP-ubiquitin recruitment to ∆Np63 promoter normalized to input values and expressed as mean ± SD of three replicate samples from one representative experiment out of two.