Cell cycle-dependent regulation of MCPH1 transcripts.

<p>(A) HeLa cells were arrested in G1 phase by double thymidine block. Cultures harvested at various time points after release were analyzed using flow cytometry. (B) Plots represent numbers of cells as a function of their DNA content. A total of 90% of the cells synchronously progressed into S phase (0–4 h), entered G2 phase (4–6 h), started passing through mitosis after 7 h, and were completely in G1 phase after 12 h. (C) Levels of MCPH1-FL (diamonds, solid line), MCPH1Δe9–14 (squares, dotted line), and MCPH1Δe8 (circles, dashed line) mRNA. Data represent means ± S.E.M. of three independent experiments and are normalized to the expression levels of <i>GAPDH</i> and <i>B2M</i>.