Figure 1.

CRB3 is an important mediator of contact inhibition. (a, b) Expression of CRB3 mRNA and protein was examined in cells grown under sparse and confluent conditions by real-time PCR and immunoblot analyses, respectively. GAPDH was used as a loading control. (c, d) The localization of CRB3 in MCF10A and MDA-MB-231 cells grown under sparse and confluent conditions was determined using immunofluorescence. Scale bar, 25 μm. (e and f) The efficiencies of CRB3 knockdown and upregulation were determined by immunoblot analysis and real-time PCR. ***P<0.001. Data are mean±S.D. (g) The proliferation of MCF10A and T47D cells was evaluated for six successive days using a cell proliferation assay. *P<0.05, **P<0.01. Data are mean±S.D. (h) A cell cycle analysis was used to measure the cell cycle distribution of cells grown under sparse and confluent conditions. (i, j) BrdU incorporation was examined to reveal DNA synthesis in cells grown under sparse and confluent conditions. **P<0.01, ***P<0.001. Data are mean±S.D. (k) The protein expression levels in the indicated cells were detected by immunoblotting