Figure 3

Characterization of heterochromatin and telomere motion. (A) Colocalization of telomeres using green fluorescent protein (GFP)-TRF1 with heterochromatin stained by CFP-HP1α shows that most telomeres do not colocalize with the heterochromatin foci in UMUC3 cells. (B) Track4D analysis of heterochromatin motion in three-dimensional (3-D) space shows that the UMUC3 cell heterochromatin moves with much less motion than UMUC3 cell telomeres. (C) Histogram of D values for heterochromatin motion, N = around 400 heterochromatin spots. Heterochromatin hardly moves, and D values for heterochromatin fall in the range reported (mode around 1 × 10^-4 μm²/second). (D) 3-D trajectory image of tracked telomeres in a UMUC3 nucleus. The enlarged view shows the motion path of a representative jittering telomere and its non-directional movement and telomeric motion conforms to a 'constrained non-directional walk' description. (E) A scatter plot of diffusion coefficients of telomeres against distance from the periphery shows that there is no significant association of telomere movement with the nuclear periphery, and no correlation between distance to the periphery and motion characteristics.