Chk1 overexpression decreases Cdk2 activity.

<p>(a) Isolated chromatin and (b) sperm nuclei from reactions in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0129090#pone.0129090.g008" target="_blank">Fig 8B</a> were subjected to gel electrophoresis and western blot analysis using indicated antibodies. Relative protein levels normalized to the loading control Orc2 or histone H3 are indicated below. (c) Western blot for Cdk2 of nuclear lysate (input), mock and Cdk2 IP, (d) Histone H1 kinase assay of cdk2 or mock immunoprecipitates (IP) of nuclear lysates in the absence or presence of recombinant Chk1, duplicates for Cdk2 IPs (e) Quantification of relative histone H1 kinase activity in (d) and two other independent experiments, means of three independent experiments with SEM (t-test: P values < 0.005), * significant difference (P < 0.05).