Figure 4.

Targets for p27^Xic1 in vivo. Embryos were not irradiated (control) or were irradiated after the MBT (stage 9 γ-IR), collected at different times, and frozen. (A) The total level of p27^Xic1 at the indicated times. (B) Samples equivalent to five embryos were precipitated with p13^suc-1 beads, and the bound proteins were analyzed by Western blotting with anti-p27^Xic1 antibody. (C) Association of p27^Xic1 with cyclin A2 complexes was detected by immunoprecipitation with cyclin A2 antibody and analysis of the precipitates by Western blotting with anti-p27^Xic1 antibody. (D) Samples from embryos irradiated after the MBT were immunoprecipitated with anti-Cdk4 antibody and blotted with anti-p27^Xic1 antibody.