Figure 6.
Knocking STRAP down results in cell cycle-dependent enhanced expression of p21Cip1. (A) Total cell lysates from serum-starved HeLa cell clones (as described in 5A above) were analysed for p21Cip1, p27Kip1, p53, CDK2, CDK4 and β-actin expressions by immunoblotting using respective antibody. (B) Total RNA from the cells above was prepared at indicated time points and levels of p21Cip1 mRNA were measured by qRT-PCR. (C) ChIP assay was performed from cells mentioned above using control IgG or anti-Sp1 antibody. PCR amplification was done with the proximal region of p21Cip1 promoter. The results are expressed as percentages of immunoprecipitated DNA compared to total input DNA. Significance levels were determined by Student's t test. *, P < 0.05 **, P < 0.01, when compared with the corresponding control.