Modeling cyclin B1 expression in G1 and G2.

<p>This figure is analogous to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g003" target="_blank"><b>Figure 3</b></a>. (<b>A</b>) The distribution of cyclin B1 expression at the exit point for G1 was gated from the G1/S region (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g002" target="_blank"><b>Figure 2B</b></a>), converted to log values, and fit with a Gaussian function to determine mean and deviation. (<b>B</b>) The values obtained from the fit in (A) were used to constrain the position and width of the exit position in the distribution of cyclin B1 fluorescence of G1 (gated from region 5, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g002" target="_blank"><b>Figure 2B</b></a>). The peak position of this distribution was set as the lower (background) level position, using the CV of the exit function. A center component was constrained with the same CV and a middle position between the lower and exit components. Amplitudes were loosely constrained to achieve continuity within the cyclin expression curve, as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g002" target="_blank"><b>Figure 2</b></a>. (<b>C</b>, <b>D</b>) The regions, S/G2 and G2/M, (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g002" target="_blank"><b>Figure 2B</b></a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g004" target="_blank"><b>Figure 4</b></a>) were used to gate the cyclin B1 distributions for entry to and exit from G2. Each distribution was fit to a Gaussian function. (<b>E</b>) The means and deviations of these functions were used to constrain the lower and upper Gaussian components of a three part function to fit the G2 distribution of cyclin B1. The same constraints on amplitude were applied as for the cyclin A2 distribution. (<b>F</b>) Interphase and (<b>G</b>) mitosis expression plots for cyclin B1 were determined as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g002" target="_blank"><b>Figure 2</b></a> for interphase and as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038275#pone-0038275-g004" target="_blank"><b>Figure 4</b></a> for mitosis. Gray symbols = G1 determinations. Black symbols = S phase values. White symbols – mitosis determinations. G1 and G2 values were from Gaussian fitting as shown in B and E.