Fig. 2

Chromosome-specific dynamics of CENP-A distribution. a Frequency distribution of the difference in the total CENP-A intensity (amount of CENP-A) between sister centromeres of chromosomes 1, 17, X, and Y. Nascent CENP-A fluorescence (green or red) on representative chromosomes represents specific cell cycles (i.e., Cycle 1 and Cycle 2). b Quantitation of CENP-A fluorescence (arbitrary fluorescence units, AFU) at single sister centromeres in two different cell cycles for chromosomes 1, 17, X, and Y. c, d Quantification of total CENP-A fluorescence (c) or segregating units (d), based on stochastic fluctuation of CENP-A fluorescence, at the centromeres of four human chromosomes. Values for HSA1 and HSA17 represent both chromosomal homologs. The diploid cell line studied was male, so HSAX and HSAY values represent haploid chromosomes. Dotted pink line indicates the average across all human centromeres. Mean and standard deviation are indicated for each centromere. e The range in CENP-A fluorescence quantified as segregating units (SU) between HSA17 homologs whose alpha satellite arrays vary in size by 2 megabases. Only p values <0.01 were considered significant. Mean and standard deviation are indicated. f The distribution of nascent CENP-A segregating units normalized to total CENP-A, looking across four different cell cycles. The pink dotted lines illustrate dilution of CENP-A over four cell cycles. Bars represent data from three different experiments, each of which included two of four nascent CENP-A labelings, i.e., Cycles 1 and 2 (black bars), Cycles 1 and 3 (medium gray bars), and Cycles 1 and 4 (light gray bars). g The distribution of nascent CENP-A segregating units normalized to total CENP-A, looking across two different cell cycles at the centromeres of specific human chromosomes. Each bar represents the centromere of a single chromosome. Dotted pink line indicates the dilution of CENP-A over two cell cycles